Notebook
Title
Notebook
Description
RAF notebook. Contains notes on axis of aircraft, stability, heat, temperature, petrol, carburettors, fuels, thermal efficiency, electrics, physical laws, atmospheric pressures, ohms law, ignition, electromagnetic induction, power/weight ratio, torque, drag, detonation. exhaust, cetane number, fuel burning and other items concerning flying.
Creator
Coverage
Format
Multi page notebook
Conforms To
Publisher
Rights
This content is available under a CC BY-NC 4.0 International license (Creative Commons Attribution-NonCommercial 4.0). It has been published ‘as is’ and may contain inaccuracies or culturally inappropriate references that do not necessarily reflect the official policy or position of the University of Lincoln or the International Bomber Command Centre. For more information, visit https://creativecommons.org/licenses/by-nc/4.0/ and https://ibccdigitalarchive.lincoln.ac.uk/omeka/legal.
Identifier
MGouldAG1605203-160708-07
Transcription
[THIS NOTEBOOK HAS BEEN WRITTEN USING THE RIGHT-HAND PAGES ONLY, RIGHT TO THE END AND THEN TURNED OVER TO CONTINUE BACK ON THE OPPOSITE PAGES, THEREFORE THIS TRANSCRIPTION FOLLOWS THE SAME FORMAT]
1605203
A.G. GOULD
CLASS B
DIRECT ENTRY
F/E 2
Form 619.
ROYAL AIR FORCE.
Notebook for use in Schools.
[Calculations]
[Page break]
[Indecipherable words]
[Page break]
[Underlined] [Indecipherable word] of Aircraft [/underlined]
When aircraft is in rigging position Longitudinal Axis is Horizontal. This applies to Lateral Axis.
Normal or Vertical Axis passes through Centre of Gravity
Rolling. Movement about the Longitudinal Axis
Pitching. Movement about the Lateral Axis
Yawing. Movement about the Normal or Vertical Axis
[Underlined] Control [/underlined]
(1) Longitudinal Control. – Control about the Lateral Axis (i.e. control in pitching) effected by means of [underlined] elevators [/underlined].
2) Lateral Control. – Control about the Longitudinal Axis (i.e. Control in rolling) effected by means of [underlined] ailerons [/underlined].
(3) Directional Control. – Control about the Vertical Axis (i.e. Control in yawing) effected by means of [underlined] rudder [/underlined].
(4) Differential Control. – Control which enables the inside aileron on a banking turn to be moved up through a greater number of degrees when the outside one moves down. This can also be effected by the use of Frise ailerons. So that planes are fitted with Differentially controlled Frise ailerons.
[Underlined] Inherent Stability. [/underlined]
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[Underlined] Heat. [/underlined] Tends to produce a rise in temperature in a body When a body undergoes a [underlined] change of state [/underlined] eg. solid to liquid or liquid to gas: there is no change in temperature. Heat in measured in British Thermal Units BTU’s
1 BTU = Amount of heat required to raise temperature of 1 lb of water by 1 degree Farenheit [sic]. e.g. to raise the temperature of 20 galls by 100° F would require 20,000 BTU’s
Temperature is a level
Heat is a quantity
[Underlined] Temperature [/underlined] may be compared with the pressure of a water supply and heat with the quantity of water. We measure temperature by means of a thermometer.
To calibrate a thermometer find the lower fixed point be [sic] standing it in melting ice, the higher point is found by holding it in steam from boiling water. 0° C = 32° F 212° = 100° C
[Formulae]
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[Graph]
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[Graph]
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[Calculations]
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[Blank Page]
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A/C starts from A & flies 200 miles N Scale Drawing
A/C flies 100 miles Course 120° Then 200 miles Course 210° then 300 mile Course 330° How far is A/C from A.
[Diagram]
[Diagram]
[Page break]
[Blank page]
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[Underlined] Heat 2. [/underlined]
[Underlined] Solid, Liquid & Gaseous States [/underlined]
Most substances can exist in either of the above states. The essential difference between these states is the way in which the ultimate particles of the substance are arranged.
[Underlined] Solid. [/underlined]
The particles are unable to move except for a slight vibration
[Underlined] Liquid. [/underlined]
The particles are free to move, but are restricted by the presence of other particles.
[Underlined] Gas or Vapour. [/underlined]
The particles move very rapidly, completely filling the vessel containing them, and only slightly effect each other.
[Underlined] Fuel for an Internal Combustion Engine. [/underlined]
Only a liquid or a gaseous fuel is suitable for an I.C.E.
In most I.C.Es the fuel leaves the carburettor as a liquid and enters the cylinder as a gas or vapour.
[Underlined] Latent Heat. [/underlined]
In order to change a Liquid into a Vapour Heat must be supplied, the amount of heat required to change 1 lb of the liquid into vapour is called the latent heat of [deleted] the liquid [/deleted] vaporization of the liquid.
[Underlined] Water. [/underlined] – 536 Centigrade Heat Units
[Underlined] Alcohol [/underlined] – 225 CHU.
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[Blank page]
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Petrol – 75 CHU’s
In the case of the above liquids vaporization will on at atmos. condition, the necessary heat being obtained from the surroundings. If heat is supplied to the liquid the rate of vaporization increases until finally a temperature is reached at which the liquid boils. A pure liquid has a fixed and definite boiling point at standard ATM
[Underlined] Carburation. [/underlined]
To produce the necessary power in an I C E heat must be produced. This is done by burning a mixture of fuel and air.
The function of the Carburettor is to supply to the engine the necessary mixture of fuel and air.
In practice the time allowed for the carburation process is of the order of 1/300 of a second.
The following factors are responsible for this extremely rapid combustion.
(1) Through mixing of the fuel vapour and the air.
(2) The increase of pressure caused by compression
(3) The turbulence in the charge
(4) Choice of a suitable air-fuel ratio.
Methods of supplying the air-fuel mixture to the cylinders
(1) Direct injection to [underlined] each [/underlined] cylinder during inlet stroke, by a mechanical pump.
(2) Injection of fuel into induction pipe under slight [inserted] Stromberg [/inserted] pressure.
(3) Fuel is delivered into the choke by a discharge nozzle and the necessary pressure required is obtained from the depression.
[Page break]
[Underlined] Fuels. [/underlined]
Petrol is divided into Hydrocarbons ie. Aromatics and Parafins [sic]
Parafins [sic] have poor and Aromatics good, anti detonation.
Flame rate is amount of mixture burned in [indecipherable word] feet per second.
[Underlined] Variation of Mixture Strength for different conditions [/underlined]
[Diagram]
[Underlined] Thermal Efficiency. [/underlined]
[Underlined] Heat generated to do useful work at 100 [/underlined]
Heat generated by combustion in cylinder.
[Underlined] Process of Combustion. [/underlined]
Petroll [sic] = Hydrogen + Carbon
Air = Oxygen + Nitrogen + Hydrogen.
[Formulae]
[Page break]
[Underlined] Heat. [/underlined]
1 C H U represents is work done 1400 ft lbs of work
1 B T U represents is work done 778 ft lbs of work
1 lb of Petroll [sic] 18000 BTUs
Pressure Relief Valve
In liquid cooled system there is a tendency for the coolant to boil with increased altitude this is because the heater tank is open to atmosphere and this is decreasing. It is necessary to fix a pressure relief valve in the heater of tank and this keeps the pressure of the boiling point of the coolant 2 to 2 1/2 lbs above normal value that is 30 lb above Atmospheric pressure.
[Graph]
[Page break]
70% Water 3-% Ethylene Glycol Freezing point – 60° C.
Directorate of Technical Development. Fuel DTD 230
Oil 109.
[Underlined] Mixture Strengths Required. [/underlined]
Fuels consist mainly of [underlined] hydrocarbons [/underlined] such as C7 H16 (Heptone).
Or combustion by H 16 plus 6 oxygen (from air) [symbol] CO2 + H2O (water).
To supply enough oxygen for complete combustion, [underlined] about [/underlined] 14 1/2 lb of air is required for each pound of a [underlined] typical fuel
[Underlined] Economical [/underlined] Cruising.
In practice the time available for the combustion is of the order of 1/300 th of a second, and if the mixture is “chemically correct” combustion is not complete.
To ensure complete combustion a slight excess of air must be provided. The usual mixture used for economicall [sic] cruising is approx. 5% weak.
[Underlined] Detonation [indecipherable words] [/underlined]
Occurs when the latter portion of the charge becomes raised above its [underlined] Spontaneous Ignition Temperature [/underlined]. It results in a [indecipherable word] rise in pressure, which causes the familiar “[indecipherable word]” loss in power: overheating.
Detonation may be prevented by.
(1) Using fuel of as high an antiknock value (ie High Octane) as possible.
(2) High Pressures I e high Compression Ratio & High Boost Pressure tend to cause detonation
[Page break]
(3) Weak mixtures cause detonation, rich mixtures prevent detonation.
(4) Low revs if accompanied by moderate boost. [indecipherable words]
[Underlined] Electrics. [/underlined]
[Underlined] Amps [/underlined].
[Underlined] Symbols [/underlined]
[diagram]
[Underlined] Units. [/underlined]
Current. [Underlined] Amperes [/underlined] (Amps). An amp is a certain number of electrons per second.
Electromotive Force. (E.M.F.) (Electric pressure – Voltage)
[Underlined] Volts [/underlined]. The emf of a single cell accumulator is always 2 volts
[Underlined] Resistance. [/underlined] Measured in [underlined] Ohms [/underlined] Resistance of a wire depends upon its length, thickness and its material.
The greater the length the higher the resistance
The greater the thickness the lower the resistance
[Underlined] Ohms Law. [/underlined]
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[Diagrams]
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[Obscured word] – anything which causes motion, acceleration or tends to cause motion.
[Obscured word] Weight – lbs
[Obscured word] = F. distance
[Obscured word] Force multip [obscured letters] by distance in which force acts.
Foot lbs. Work done when 1 lb is moved 1 foot = 1ftlb
[Obscured word] Machines. [Indecipherable word] is rate of doing work = ft lb per min.
[Obscured word] [Underlined] Power [/underlined]. – 33,000 ft lb per min 500 per sec.
[Obscured word] Potential / Temperature / Magnetic / Sound.
Kinetic / Electric / Light
[Obscured word] = Work output / Work input
[Obscured word] = Friction and other resistance. output.
[Obscured word] of forces
[Page break]
[Underlined] Charles’ Law. [/underlined]
The volume of a gas at [underlined] constant pressure [/underlined] will vary with the temperature i.e. for a 1° C rise in temp. the volume will increase to 1/273 of its original volume, this is called the coefficient of expansion of a gas.
[Underlined] Boyles law. [/underlined]
The pressure of a gas at constant volume will very with the temperature.
Thus the two laws in one mean, with a fixed volume the pressure will vary with the temperature
[Underlined] Density Variation with altitude [/underlined]
[Deleted] Sea Level [/deleted] [Underlined] Height Pressure [/underlined]
[Table]
Temperature drops 2°C for every 1,000ft in height.
[Page break]
[Underlined] Ohms Law. [/underlined] Voltage = Current. Resistance
[Formulae]
[Diagram]
[Underlined] Series & Parallel Circuits [/underlined]
[Diagrams]
Lamps and other components are places in parallel and not in Series because (1) they can’t be switched on & off separately if in series (2) if one component fails all the rest go out of action in series (3) To maintain the current in the circuit an increase in voltage would be necessary for each new component.
[Diagrams]
[Page break]
[Deleted words]
[Diagram]
[Underlined] Ammeter Connections. [/underlined]
To ensure the current is any wire the wire must be broken and the ammeter inserted in the gap i.e. Ammeter in series
[Underlined] Voltmeter Connections [/underlined]
To measure the EMF or Voltage between any 2 points in a circuit, connect the VM to these points without breaking the circuit I e connect V.M in parallel.
[Diagram]
[Page break]
[Underlined] IGNITION [/underlined]
The region around a magnet is called a magnetic field. Magnetic lines of force can be shown by iron filings and they show the direction of the magnetic force. Close together at the poles, far apart away from the poles, [deleted] this distance apart [/deleted] The number of lines of force per unit area is called the flux, their direction is from N to S and each is a complete circuit.
[Diagrams]
[Underlined] The Magnetic Effect of a Current. [/underlined]
When a current is passed through a wire a magnetic field is produced, the direction is given by the thumb rule. If the hand represents the direction of the field the thumb = direction of current and vice versa.
[Diagrams]
[Page break]
[Underlined] Electro Magnetic Induction. [/underlined]
Wherever line of force and a conductor or EMF is involved is it. The greater the no of EMF per second the greater the voltage. If an EMF is involved in a wire by a magnetic field the EMF can be increased by (1) increasing coil (2) increasing strength of field 3 Making lines of force and the coil more rapidly
[Diagram] Key closes – Current grows – lines of force radiate and are cut by [indecipherable word] coil.
[Page break]
[Diagram]
[Underlined] Supercharging. [/underlined]
[Diagram]
[Underlined] Power Weight Ratio [/underlined]
Kestrel 1.87 Merlin 20 1.12 Hercules 11 1.04
Power output depends upon Mech Eff – Thermal Eff – [indecipherable word] Eff – Engine Speed
[Underlined] Reasons for Supercharging [/underlined] To maintain low level [indecipherable word] at Altitude & to increase V. E. To obtain more power at [indecipherable ] Eff I .e more V E.
[Page break]
[Diagram]
Oil Temperature. Bottle & tube filled with mercury & must be kept clear of all heated parts
Vapour pressure type – Ethyl Ether – Coolant Temperature [underlined] partially filled only [/underlined]
Colour of [indecipherable word] – Oil – Yellow Coolant – Blue Fuel & [indecipherable word] Red.
When fitting instruments start from cockpit & work to engine using brass nuts & bolts & anti vibration washers
Engine temp taken by Thermo Couple consistency of 2 dissimilar metals [deleted words], which generates slight E M F which is measured by Pyrometer which is Mille Volt Meter. Metals Used are Constantin [indecipherable word] Cupro Mickel positive.
[Underlined] Tachometer Drive [/underlined] Driving Cable must not be [indecipherable word] inside a 9” radius. Centrifugal drive. Cable drives at 1/4 Speed stepped up by [indecipherable word] gear to engine speed in instruments. Should not be taken within 18” of Compass.
[Underlined] Telelevel Guage. [/underlined] Fuel Contents
Cable must be wound to top of drum before tanks are filled, to check level turn back until cork float locks on rocket.
This consists of metal or cork float operating up & down a brass tube, inside tanks. In the case of metal float this
[Page break]
[Calculations]
[Underlined] Torque [/underlined] [Formula]
N.B Force & Arm must be at rightangles [sic].
[Underlined] Drag [/underlined]
[Underlined] Form Drag [/underlined] is sue to the formation of vortices behind the body caused by the action od viscosity. These vortices prevent the fluid from closing behind the body as it opens up in front and so prevents the fluid from exerting the same pressure on the back of the object or on the front. This pressure difference causes drag. Form drag can be reduced by streamlining.
[Underlined] Skin Friction. [/underlined] is due to turbulence in the boundary layer. Surface roughness (I e rivets) paint with matt finish fabric etc causes increase in skin friction.
[Underlined] Induced Drag. [/underlined] is due to wing tip vortices and can be reduced by proper shaping of the wing tips and by using high aspect ratio
[Page break]
[Underlined] Retonation. [/underlined]
As charge burns temp & press increase – unburnt portion is compressed by burnt portion & its temp is raised by compression. If the rate of temp increase is too high spontaneous combustion will occur [symbol] [indecipherable word] rise in pressure in this part of the charge. If rate of burning is fast – no increase in volume and it is poss. to get a local pressure of 1 Ton [symbol]. This high pressure causes a shock or wave, which strikes the cylinder walls and causes a knocking sound.
[Underlined] Harmful Effects [/underlined].
(1) Rise in temp on piston crown. (2) Max stress on Material due to excessive temp & pressure. (3) Alloy of piston and crown worn away by excessive scarring. (4) Excessive loads on bearings may cause a breakdown of lubrication.
[Deleted number] [Underlined] Factors & Causes of Retonation [/underlined]
(1) Excessive Boost Pressure (2) Too high a [indecipherable word] Ratio (3) Nature of fuel. (4) Turbulence (5) Poor shape of cylinder.
[Underlined] Exhaust valve difficult to cool.
[Underlined] Exhaust Gas Analysis. [/underlined]
[Table]
[Page break]
Limit of Dope 4 cc per gallon.
[Underlined] Octane Number. [/underlined]
The reference point for Oct is a mixture of 81% Iso Octane & 13% Normal Heptane. If the fuel under that has the same resistance to detonation as the ref fuel above its Octane No. is said to be 87. [symbol] 100 Octane is equivalent to [indecipherable word] book value 100% for Octane & No per cent Normal Heptone.
Latent Heat of British Petrol averages 135 BTU’s per lb.
[Underlined] Requirements of Good Air Craft Fuel [/underlined]
(1) High Calorific Value (2) Hish Anti [indecipherable word] value (3) Good volubility. (4) High Latent Heat of Vaporization (5) Low Freezing Point (6) High Specific Gravity (or [indecipherable word] of G at any altitude) (7) Low Gear & Acid for test.
[Underlined] Heat 5 – 6. [/underlined]
[Calculations]
Ht Energy = 1 BTHU
Mech Energy = 778 ft lb [indecipherable word]
1 gall/min 7.2 lb.
Max En Cruising 7.2. 18000 BTU
Work done 7.2. 18000. 778 ft lb.
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Work done in cylinder [calculation]
[Calculations]
[Formulae]
[Calculations]
[Page break]
[Underlined] Effect of High Temp on Cylinder. [/underlined]
(1) Softening (2) Loss of [indecipherable word] (3) Erosion. These will detonation, temp rise may be by 2,000° [symbols] great necessity for Cooling (1) Piston (2) Cylinder Walls (3) Cylinder Block
[Diagram]
[Table]
[Page break]
From figures it can be seen that with constant RPM & constant Boost, R.A will be [indecipherable word] in M Gear when the Boost after RA has fallen [underlined] by [/underlined] +2 change to S Gear then switch RA in S Gear this is full throttle height with constant RPM & Constant Boost, if greater full throttle height needed increase R.P.M.
[Page break]
Drag – Made up of Active – Parasite – Interference Drag.
Active from lifting surface Parasite from Non lifting surfaces Interference from point/surface [indecipherable word] another
Active & Parasite Drag can be divided in Form + Skin Friction Active for also Induced drag.
[Diagram]
[Underlined] Form Drag [/underlined] is due to slope & angle of attack of the object. Reduced to & [indecipherable word] by Streamlining.
[Underlined] Skin Friction [/underlined] is due to the roughness of any exposed surface & the Viscosity of the air. This is reduced to a minimum by making all exposed surfaces as smooth as possible. {polishing – flush [indecipherable word]).
[Underlined] Induced Drag [/underlined] is due to wing tip vortices. Reduced to a minimum by having an Aspect Ration ( [indecipherable words] as large as possible.
Relationship between drag & Air-speed.
Drag depends upon air speed; i.e. the speed of the object relative to the air in which it is moving. If the airspeed is doubled then the drag us more than doubled, it is multiplied 4 times. (The speed squared.)
[Table]
[Page break]
Relationship between Drag & Air Density.
Drag is proportional; to Air Density.
If the Air Density is doubled, then, other thins being equal, the drag is doubled.
[Formulae]
[Calculations]
[Page break]
[Calculations]
I H P = PLANE [symbol] 33000
P = Mean effective pressure (lb [symbol]”)
L = Stroke in ft
A = Area of [indecipherable word] ([symbol] “)
N = No of Cylinders [deleted letter]
E = No of Explosions (Power Strokes) [formula]
[Underlined] F 5 [/underlined]
As density of air decreases drag decreases. Venturi Principle. Increased speed of flow through a neck us accompanied by a decrease of pressure in the sides. [Diagram[
[Page break]
[Calculations]
[Underlined] Example] [/underlined]
An Engine rotates a flywheel of 4 ft diameter against a force of 2000lbs. Find (a) Torque (b) BHP developed at 1000 RPM.
[Calculations]
[Page break]
[Formulae]
[Underlined] Centre of Gravity [/underlined]. (C.G.) us the point at which the resultant weight of an object may be considered to act.
An object will balance about its centre of gravity. C.G. is the point at which the resultant turning effects (moments) cancel each other.
[Formulae]
[Underlined] Landing Speeds. [/underlined]
For a given landing C & S. are [indecipherable word] and [formula] must be kept equal to the weight of the aircraft. In order to decrease V, CL must be increased by increasing the angle of attack. The angle of attack cannot be increased beyond the stalling angle. (The speed corresponding to the stalling angle is called the stalling speed.
[Underlined] Slats. [/underlined]
If a properly [sic] slat is placed in front of the main wings with a suitable slot in between the angle of attack can be increased beyond the normal stalling angle before the airflow breaks up over the top surface this means an increased
[Page break]
Lift coefficient and therefore a lower stalling speed.
Disadvantages of Slats.
The fuselage must be tilted at a large angle giving poor visibility from the pilot’s cockpit and necessitating a high & [indecipherable word] undercarriage.
[Underlined] Flaps. [/underlined]
Flaps, like slats, cause a decrease in the stalling speed, but only the flap needs to have the angle to the airflow increased. So that the a/c need not be so high and the pilot has a better view. The increased drag reduces the excess speed (Landing speed – stalling speed) more quickly
[Underlined] Carburation. [/underlined]
Weak – Econ Cruising 16:1 [underlined] not with high boost [/underlined] } [indecipherable word] + Main Jets
Chemically Correct – 15:1 }
Rich – Power 13:1 }
Rich – Slow Running – S.R. Jets
Rich – Rated Condition – Max Climb – 12:1 – Power Jet
Rich – Takeoff – 11:1 – Enrichment Jet
Deceleration – Accelerator Pump & Delayed Action Pump.
Altitude Mixture Control
Corrected Jet C.H. supplies fuel ‘into’ the diffuser above the Main Jets.
Lift depends on (1) Lift coefficient (- a number depending on shape & angle of attack. (2) [Underlined] Plan [/underlined] area of lift surface (3) Air density (4) Air speed.
[Page break]
[Diagrams]
[Underlined] Angle of Attack. [/underlined] Angle between Cord [sic] line & Flight Path.
[Underlined] Angle of Incidence. [/underlined] This is the rigging angle. It is the angle between the Cord [sic] Line& the datum line.
[Underlined] Stalling Angle. [/underlined]
Angle of attack at which the lift is a maximum.
[Underlined] Optimum Angle [/underlined] Angle of attack at which the lift-drag ratio is maximum. At the same time, the drag of the whole aeroplane is at a minimum. Thus, it is the most efficient angle of attack. And thus an aircraft will therefore cruise most economically in this angle.
Relation between speed & angle of attack. If the speed of an aircraft is increased the lift developed will increase and the aircraft will climb. If the speed is decreased the lift
[Page break]
Developed decreases and the aircraft will lose height. [Symbol] If it is required to stay at the same altitude, as the speed is increased the angle of attack must decreased [sic] and vice versa. For each angle of attack there is only one speed for steady horizontal flight, and the slowest speed will be the aspect at the stalling angle. i.e. the stalling speed.
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[Calculations]
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[Underlined] MERCURY SERIES [/underlined]
9 Cylinder Air Cooled Radial Supercharged Bore 5 3/4“ Stroke 6 1/2“, Compression Ratio 6 1/4 – 1 Reduction Gear Ratio Mercury 8 & 8A .572 – 1 Direction of Rotation of Airscrew Shaft Left hand from rear – anti-clock. D of R of Crankshaft Left hand Supercharger Gear Ratio 9.4 – 1 Dry Weight Mercury 8-1002 lb.
Cylinder Numbering ([indecipherable words]) anti-clock No 1 vertical.
Fuel – L & R 230 (87 Octane) Oil – D 7 D 109 pure mineral oil.
Pump pressure – Normal 80 lb [symbol]” Minimum 5 minute limit – 65lb [symbol]”.
Consumption 6-12 pints per hour at 2400 RPM. Inlet oil temperature Maximum for takeoff (high initial oil pressure device in operation) 5° C.
Max for continuous cruising 70° C. Max for climbing 80° C. Emergency Max (5 minute limit) 85° C.
[Underlined] Ignition [/underlined]
Firing order 1-3-5-7-9-2-4-6-8. Ignition Type 2 Watford SP – 9/4 1 290 single contact breaker or SP 9/6 35 twin breakers. D or R anti clockwise 9/8 engine speed. Timing – Tally advanced 35° B.T.D.C. Ignition control – automatic advance & stand.
[Underlined] Carburettor [/underlined] AYT 85 E
[Underlined] Valve Timing [/underlined] Inlet opens 29° BTDC Inlet closes 47° ABDC Exhaust opens 76° BBDC Exhaust closes 40° ATDC [Underlined] Valve [/underlined] clearances cold, Inlet 4 close, Exhaust 6 close. Starter system Load & electric timing gear. Airscrew variable pitch.
[Diagram]
[Page break]
[Diagrams]
Only 1 main bearing Steel shell – nickel alloy or white metal outside.
[Calculations]
[Page break]
[Underlined] 9 Cylinders [/underlined] 1-3-5-7-9-2-4-6-8 – 40° difference between each stroke
(1) 70 C Compression (2) 40° BTDC EX (3) 80° BIDC COMP (4) 60° ABDC EX (5) 20° ABDC COMP (6) 20° BBDC. POWER (7) 60° BBDC IND (8) 80° ATDC POWER (9) 40° ATDC INDUCTION.
[Underlined] [Deleted words] [/underlined]
Lower Cylinder Tappets below Centre Line of Engine consist of Oil Sleeve Gets Spring Loaded Leather Oil Seal 2 Holes in Oil Sleeve line up with 2 Holes in Carb [indecipherable word] Upper Tappets have no oil sleeve but have Seal. Carbon Steel Task Rods Hollow Steel hardened at ends. Tappet wheel mounted on fully floating bush and fully floating pin.
[Diagram]
[Underlined] Reduction Gear [/underlined] To find reduction find no of teeth on Driver & Drive. [Formula] Driver 60 teeth [indecipherable word] 50 teeth Reduction [formula]
Collector Ring Fitted in front of Fixed Bevel to supply oil to A/S. Bearings – Air Starter Thrust, Bevel Pinions Centrifugal - Rear Bearing – Tendency of Bevels to separate.
[page break]
[Underlined] Duplex – Spring loaded Vanes – fuel Pump. [/underlined] 250 galls P.H. 2500 R.P.M.
[Indecipherable words] rotors in steel lined housings having 4 vanes
[Diagram]
[Underlined] Bristol High Metal Oil Pressure Pump. [/underlined] 80lb [symbol]” 600 galls p.h.
[Page break]
[Underlined] Magneto Timing - Mercury. [/underlined]
(1) Using a P.P.I find T.D.C. (Compression Stroke) on [underlined] No. 6 [/underlined] Cylinder
(2) Set Timing Plate in position and turn engine back so that [underlined] No 6 [/underlined] piston is [underlined] [deleted] 25° [/deleted] BTOC Compression. [/underlined] 29° [underlined] SP 9/4 [/underlined]
(3) Prepare mag as follows :- Insulate the Primary Winding – Set C. B. points to [underlined] .012” [/underlined] – Fully advance magneto – Turn mag until rotor is opposite [underlined] No. 6 [/underlined] segment and the C/B points are just about to open.
(4) Line up degs on magneto to slots in drive and fit mag to engine.
(5) Check with lamp and battery and make adjustment where necessary on the fine adjustment (1 Serration = 2 crankshaft degrees) Timing to within 1°.
(6) Repeat on other mag and test both mags for synchronisation to 1°.
(7) Remove mags and :- Remove insulation – Remove advance clips – Insert split pins in fine adjustment nuts.
(8) Replace mags on engine.
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Mercury Lubrication – Dry Sump – 80lb [symbol]”
Component lubricated by High Pressure – C/S Tailshaft Bearing – Big End Bearing (Start shell White Metalled freely drilled) – Con Sleeve bearing – Air Screw Tail Shaft Bearing – Bevel Pinion Bushes – all the bushes in Rear Cover – [underlined] Wrist Pins [/underlined] Cross Drive Shaft plain bearing lubricated at 80lb [symbol]” – BTH Air Compressor bearing – Tacometer – Fuel Pump.
Hand Priming & Greasing.
- On Installation or period of standing exceeding 5 day The nipple at the front of the new cover. [Indecipherable word] new [deleted word] Supercharger bearing – Nipple between 1 & 2 cylinders To lubricate front S-chgr & gears (Spring [indecipherable word] Used) Nipple on end of cock rocker arm. Lubricate revolving button of valve mechanism. Grease nipple at rear of rocker box. Lubricating the rocker arm ballbearing.
[Underlined] Felt Pad. [/underlined] The Inlet Push Button Inlet Rocker arm buttons positioned to front of rocker box cover.
[Underlined] The Felt Pad [/underlined] fastened inside Rocker Pad lubricate Exhaust push rod button & Rocker arm buttons. Felt washer lubricate vale stems & ends. Attached to end of each valve.
[Underlined] Splash Lubrication. [/underlined]
All ball & roller bearing are lubricated by Splash Oil. Main Forward Roller Bearing, ball Rise in front cover Back thrust occurs in revolution gear & 3 [indecipherable words] on the bevel pinions and Ball Bearing to Gravity Drive. Intermittent feed to Supercharger bearings. These bearing
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receive a squirt of oil every revolution of the Crank shaft.
Cylinder Walls – [indecipherable words] First Bellow lubricated by splash oil flung about within Crank core. All scavenge oil drain into sump between 5 & 6 cylinders, mostly Internally by internal pipe from next cover. The oil is sucked from the sump and the scavenge filter around the pump gears & by external pipe to Carb Gasket and then back to tank run above & cooler, H. I. O. P. drive supplies extra pressure to engine system when starting from cold and sprays oil onto big end assembly area [indecipherable word] between 1 & 2 cylinders & automatically cuts itself out when temperature of oil increases to a given figure. Feed to supercharger is intermittent and is high pressured by way of the C/S T/S through a duct into the aluminium tube which links up with a duct once easy revs.
[Underlined] Cooling. [/underlined]
Fins – Baffles (Inter-Cylinder) – Cowlings Gill Ring Fins increase surface area. Baffles direct airflow round cylinder
[Diagram]
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[Diagram]
Valve Timing. Tappet Clearances. Inlet 4/000 6/000
Finding the duell [sic] inlet No 6 Cylinder to TDC Compression (2) Set Tappet Clearances to 4/000 Inlet 6/000 Exhaust using [underlined] 2 [/underlined] sets of feelers. (3) Rotate Crankshaft in 1 OR [underlined] 2 [/underlined] revs. (This moves [indecipherable word] sleeve 90° in [indecipherable word]) bringing next [indecipherable word] onto No 6 cylinder. (4) Check No 6 tappet clearances and note. (5) Repeat the above for the other 2 [indecipherable word]. (6) The [indecipherable word] giving the smallest tappet clearance is the highest and all valve clearances must be set by the highest [indecipherable word] [deleted letter] or [indecipherable word].
[Underlined] Setting valve Clearance. [/underlined]
(1) Turn engine till highest [indecipherable word] (Inlet or Exhaust) is opposite no 6 cylinder and set tappet clearance. (2) Rotate Engine in D. O. R. 320 degrees (1 rev less 1 cylinder space) and set tappet clearance on No 5 cylinder. (3) Repeat for the other cylinders as above.
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[Underlined] Piston Rings [/underlined]
[Diagrams]
No. 6 ring cut square to [indecipherable word] oil in cylinder, Pitted to distinguish
[Underlined] COMPONENTS. [/UNDERLINED]
Header Tanks. Thermostats. Radiators.
[Diagram]
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Coolant Tanks made of Sheet Brass – Lagged & Baffled to prevent surge & strength of sides. [Indecipherable word] Vortex device fitted to precast in Cock. Coolant under 30 lb [symbol]”.
2 Way relief valve [inserted] duplex [/inserted] opens at 30lb [symbol]” to reduce pressure – opens inward at – 1/2 lb to maintain 14.7lb [symbol] in tank. [symbol] [Underlined] Simple type. [/underlined]
[Diagram] Thermostatic Heater Relief Valve.
(1) To permit pressure to build up in the cooling system in order to raise the boiling point of the coolant and so increase its capacity to absorb heat from the engine.
(2) To act as a safety valve to prevent the building up of excessive pressure. (3) To admit air to limit the negative pressure in the system when the engine stops. (4) To provide an escape valve for any [indecipherable word] gas that may exist in the cooling system.
[Underlined] Functioning [/underlined]
(1) When cold the thermal element cage is held down by the light spring on the top of the stop plate so closing the valve and depressing the vacuum bellow slightly.
(2) During the initial warming up, expression of the engine coolant causes positive pressure in the vacuum compartment raising the vacuum bellows into contact with the stop plate and if the pressure increase exceeds 2 1/2 lb [symbol]” in the valve will be opened, lifting the thermal cage against the light spring and so relieving the pressure.
(3) Further warming expands the thermal bellow until at 100°C the main spring abuts against the adjuster plug and becomes
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the internal and external pressures are equal the valve is in a state of balance and the total reaction is taken by the main spring.
(4) Further rise in engine temperature expands the bellow fully up to the thermal cage until it overcomes the compression of the main spring whereon the valve lifts and sets as a relief valve, operating at a pressure of 30lb [symbol]”.
(5) On Cooling, the system loses pressure until a partial vacuum is formed: the vacuum allows this contrast to open up the valve and to [indecipherable word] with atmospheric pressure.
Thermostat } fitted between heads & Rotator [inserted] 15 galls per min [/inserted]
Terrington } A coolant radiator.
[Underlined] Operation [/underlined]. When the coolant is cold the compressed air bellow keeps the radiator valve load on its seating so that no coolant can flow through the radiator. This reduces the time necessary for warming up from cold. As he engine warms up a vapour pressure is created in the [underlined] Thermo Bellow [/underlined], and at approx. [underlined] 85°C [/underlined] this pressure overcomes the pressure in the [underlined] Compensating bellow [/underlined], forcing the radiator valve off its seating. [Underlined] At 105°C [/underlined] the radiator valve is fully open, and bypass valve is closed. Should the [underlined] compensator [/underlined] become punctured then the radiator valve would open at very low temperature. While this would tend to overheat the engine it would cause no [underlined] damage. [/underlined] On the other hand failure of that thermal bellow would cause radiator valve to shut permanently and engine to overheat and seize. To avoid this risk the third bellow is fitted, incorporating a coil spring and steel spike. Failure of the Thermo balloon would cause this to be [indecipherable word] to puncture Compensator Bellow forcing Radiator valve fully open. Test by
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inserting in hot oil and raising to required temperature. When drawing from stores look to By Pass port to see if BP. Is open. If bonded with yellow do not use with 100% Glycol.
[Underlined] Jointing. [/underlined]
High pressure rubber jointing – with special metal clip. White rubber coolant. Red rubber fuel system.
[Underlined] Radiator. [/underlined]
Honeycomb type – Galley type (Cupro Nickel alloy – Glycol resisting) Cleaned with hot water 2° [indecipherable words]
[Underlined] Oil Tank. [/underlined]
Never clean with paraffin – flush with flushing oil.
[Underlined] Hoywood Air Compression [/underlined]
Viscosity Valve ([indecipherable word]
[Diagram]
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[Underlined] Viscosity Valve. [/underlined]
This valve is designed to prevent the oil congealing during long glides or overheating under full power ops in climb.
Oil from the engine flows into a chamber which is closed by two valves - one being a control valve – and the other a spring loaded relief valve. In this chamber directly in the path of the oil flow is a small filter through which a [underlined] sample [/underlined] of oil is passed through the head of the valve into the viscosity pressure chamber. When the oil is cold of viscous the sample of oil will pass through the filter but will not pass through the friction tube & pressure is built up inside the Control Valve which holds the valve on its seat and surpasses the pressure of the spring loaded relief valve. The relief valve is forced open & oil goes direct to the Oil Tank.
As the oil becomes less Viscous the pressure inside the Control Valve drops, due to the fact that the oil can escape more easily through the friction tubes, this results in the total pressure in the control valve becoming less than the spring pressure behind the by pass valve, causing the by pass valve to start closing & control valve to start opening, thus permitting the oil to flow through the cooler.
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[Underlined] OIL DILUTION SYSTEM [/underlined]
[Diagram]
[Underlined] Filters [/underlined] Maintenance – Isolate from oil circuit (cocks) – Remove drain plug [deleted word] and catch oil in container. Remove container by enclosing the set screws at the head. – Lift out the filter, reserve the wing nut & end plate. Remove the gauge from perforated cylinder Clean all parts with petrol. Replace filter gauge with new one or scrub in [underlined] parafin [sic] [/underlined]
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[Diagram]
[Underlined] Hydrostatic Fuel Contents Gauge. [/underlined]
Principal of operation. The weight of the load of fuel on the bottom of any tank exerts a hydrostatic pressure in proportion to the load of fuel [indecipherable word] of pressure gives indication of load of fuel in tank. The transmitting box capsule assembly capacity tube and indicator diaphragm from a sealed system filled with nitrogen at a predetermined pressure. Pressure of fuel on capsule assembly in transmitting box is conveyed by way of capillary tube to capsule is indicator the expansion of this capsule is measured then indicating fuel in tank
Rotary Float Fuel Contents Gauge.
[Diagram]
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[Table]
[Diagram] All Capiliary [sic] tubing [underlined] (Surplus) [/underlined] must be coiled in a diameter not less than 6” and secured with at least 3 clips.
Oil pressure to [indecipherable words] Capsule & C Tube filled with Ethyl Alcohol.
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[Underlined] Amel Fuel Pressure Reducing Valve. [/underlined] Reducing valves are necessary in order that the correct pressure is maintained at the earth. The pressure is standardised at 1.9 lb [symbol]” irrespective of delivery pressure. [Underlined] Operation [/underlined] A spring loades [sic] diaphragm is opposed by a piston and conical valve. The piston valve controls the fuel pressure and the conical valve comes into operation when the piston valve covers the ports and cuts off the flow of fuel. Provision is made for the conical valve to operate independently in case of piston valve sticking. Pressure is built up against a spring loaded diaphragm, pushing it up and allowing these valves to open or close regulating pressure of fuel. [Underlined] Installation. [/underlined] Must be fitted within 1 foot of [indecipherable word] and should be fitted horizontal or at an angle of not more than 45°, but can be mounted upside down. [Underlined] Maintenance. [/underlined] The drain plug should be removed & valve flushed out when fuel filters are cleaned. At Major inspections valve must be dismantled and examined for damage & defects, defective parts should be replaced with new ones. Diaphragm must be replaced every 1000 hours running time. Test at pressure of 2 lb [symbol]” with outlet pointing downwards a leak of only 1 drop per minute is permissible.
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Boost Pressure.
This is the pressure [underlined] above [/underlined] or [underlined] below [/underlined] Atmospheric [underlined] whatever the altitude [/underlined]. eg. 10,000 ft At Pr = 10lb [symbol]” Boost= +6 Boost Pressure = 14.7 + 6 = [underlined] 20.7 [/underlined]
[Underlined] Rated Altitude. [/underlined]
Greatest height in Standard Atmosphere at which engine can maintain Rated Boost at International RPM.
Rated Boost is Maximum Climbing.
60 miles per hour = 88 ft per second
Work done in 1 min = Drag in lb. speed in mph. 88
[Calculations]
[Underlined] Power [/underlined] = Rate of doing work = Work done/Time
550 ft lbs per second or 33,000 ft per min = 1 H.P.
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tube is fitted with a rachet so that when tank is empty the float can be moved up & down the column by means of a Bowden Cable which is housed on a dural drum inside the gauge operated by a butterfly handle mounted in centre of gauge dial. The rachet operates only when the float comes up against level of petrol. The float then takes up a horizontal position and the fixed tooth on the float engages with the rack on the tube or column & becomes locked, at [sic] it remains so until the petrol level drops & rebases the float from the horizontal position.
[Underlined] Flexible Pipes. [/underlined]
Petroflex, Superfloat, Arioflex, Duraflex.
Graphite grease on alloy nuts.
Pipes & Pipelines
Flexible Fuel Pipes. These pipes must be examined for chafing and must be properly supported against vibration, if the pigmentation has been chafed the pipe must be treated with seaplane varnish and protected with thin sheet cork. Flex pipe between filter & Carb only are stamped with date of manufacture, if date is 3 years or over pipe is U.S. When fitting avoid sharp bends & when tightening nuts care must be taken not to twist tubing, which would break internal spiral & cause restriction in pipe, do not overtighten & strip threads.
Petroflex, old type pipes have a rear [indecipherable word] & are not electrically bonded, they are fitted with a bonding eye for this purpose, this tubing is now made in two types, Low Pressure for fuel systems + High Pressure for Air + Oil systems.
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which will withstand [inserted] working [/inserted] pressures up to 700 lb [symbol]“ or 60° C. This pipe consists of an inner tube made of hog or horse skin, the gut core is covered with 2 ply cotton fabric. The tubing is reinforced with two spirals of wire, one internal and the other outside. The tubing is electrically bonded and the outer surface is protected with pigmented oil varnish Superfluid. This tubing is used in fuel and certain oil systems. The core consists of a Cellulose film, and a brass wire spiral, wrapped with layers of cotton. This is followed by rubber sheeting, the tube is finished by either a metal braided outer cover or a covering of fabric reinforced with a spiraly round wire.
[Indecipherable word] Used in air and oil systems. This tube consists of an inner core of flexible metallic tubing, over this a rubber tube is vulcanised and not wrapped. The whole is protected & reinforced by strong metallic braiding.
[Underlined] Duraflex [/underlined] Use in Air & Oil systems. Duraflex is similar in construction to the above, only more robust being 2 steel wire braids instead of one. Working pressure 1,200lb [symbol]”, at max temp of 120°C.
Fitting of end connections of all flexible types.
The end connection & couplings are designed to [indecipherable word] with A G S fittings. Where fitting new coupling, reference should be made to (A.P. 1464 A, Volume 1 Part 5 Section 5).
Protective Covering for rigid fuel pipes
Rigid fuel pipes are in certain circumstances provided with a protective covering similar in principal to that fitted to fuel tanks the covering is safeguarded against leakage of
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fuel when the pipe is fractured or holed and consists of a spirally wound layer of canvas strip solutionised to the pipes over which 2 layers of specially prepared rubber strip are applied longitudinally the whole being wound in as outer cover of spirally wound canvas. The selfsealing action is afforded by the local swelling of the rubber when it contacts the fuel, the rubber being encased in canvas is forced into the crack or hole and effectively prevents further leakage.
Selfsealing Flexible Tubing is now available for fuel pipe lines up to 1 1/2 “ bore, 2 types are now in use Type A for internal pressures up to 5 lbs [symbol]” B for 15 lb [symbol]”. In addition to selfsealing, the outer layers are treated for protection against fire. No metal is used in the construction of this tubing, the internal strength being obtained from a hellically wound plastic strip, this strip prevents the tubing from kinking at bends and when hit by a bullet it fractures with a minimum injury to the pipe this tubing is not to be used where temperatures exceed 70°C. [Underlined] Identification [/underlined] Type A Red Type B Red with Black Hellical Bands.
Rigid Pipes (Copper)
All Copper tubing used on aircraft is issued in its fully annealed condition. This Tubing had to be heat expanded or shaped in its cold state using only a fusable alloy which melts at 100°C (Boiling water). Pipes must not be rebent after use owing to fracturing propensities. When incorporating a rubber coupling to a copper pipe the ends must be first beaded
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and then tinned. The pipe must then be bonded with a tinned copper bonding strip. On Bristol Engines on oil pressure side an additional centre clip (Jubilee) must be fitted to restrain the swelling of the coupling. [Underlined] [Indecipherable word] [/underlined] Tubing must be treated in exactly same way as copper – cold shaped bonded – tinned protective packing for this pipe is brass gauge (80 mesh).
[Underlined] Stainless Steel. [/underlined]
No attempt must be made to bend or alter the setting of these pipes – when damaged ref must be made to schedule of spare parts and a new pipe ordered, as a temporary measure a copper pipe may be fitted. To protect S S pipes paint the ends in contact with rubber coupling with an air drying enamel coating the rest of the pipes with seaplane varnish, for bonding us [sic] SS strip [underlined] only [/underlined]. [Underlined] Light Alloy pipes [/underlined] are used for vent pipes for tanks not for conduits for leads & cables and are also used on some fuel oil & coolant pipes.
[Diagram]
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[Diagram]
1. Electrical Contents Gauge 2. Air Vents 3. Suction Balance Cocks 4. Delivery Balance Cock 5. Non Return Valve 6. Filters 7. Mechanical Tail Pumps 8. Priming Pumps 9. Pressure Gauges 10. Isolating Cocks 11. Drain Cocks 12. Carburettor. Pressure Side [symbol] Gravity Side [symbol]
3 & 4 closed during normal running. Vent pipes should be examined by uncoupling from tank and air pressuring. Taking care not to blow dirt into tank.
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(1) Before opening up the engines before takeoff (a) Both tank cocks should be open (b) Balance cocks in pipes which connect [obscured word] system on suction & delivery side are to be kept closed and only opened in emergency such as the suspected failure of fuel pump on 1 engine. (c) fuel pressure gauges should show the pumps are working
(2) Normal Flight (a) both Tank cocks should open (b) both balance cocks should be shut.
(3) If 1 tank is damaged (a) Open suction pipe balance pipe and shut off undamaged tanks to use as much as poss from damaged tank (b)When tank is empty close cock to damaged tank and open cock to undamaged tank, leaving suction balance cock open & delivering balance cock shut. Damage to a tank is shown by visible escape of fuel or by abnormal consumption as shown on fuel contents gauge.
(4) If one engine pump fails open suction and delivery balance cock. by this action the pump undamaged will supply both engines from both tanks. failure of a pump is indicated by a fall in pressure on fuel pressure gauge.
(5) If One Engine fails open suction balance cock only the engine which continues to run will then draw its supply of fuel from both tanks but fuel will not be delivered by the pump to the engine which has failed.
(6) If one tank & 1 pump fail (a) Open both suction & delivery cocks (b) shut off damaged tank. (c) Close cock of damaged tank when empty & open each of undamaged tank leaving both balance cocks in open position.
(7) Both pumps fail the fuel supply will be maintained by gravity.
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[Copy of following page mostly covered with blank paper]
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until tanks are practically empty, if 1 tank is not supply correct amount of fuel open 1 Suction Balance Cock.
[Diagram]
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E G 174 = Inhibiting Fuel.
Starting M C to Rich Air intake [deleted word] cold
[Underlined] Electrical fuel contents gauge. [/underlined]
[Diagram]
Alter reading on gauge be [indecipherable word] soft Iron Core breaks down strength of the different cock
[Underlined] Identification [/underlined]
Oil Pressure – Yellow Beazel [sic]
Oil Temperature Orange Bezel
Fuel Pressure } Red
Boost Gauges }
Coolant Temperature Blue.
Oil Temperature [indecipherable word] Steel - Copper [indecipherable word].
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[Deleted numbers]
Ignition
Testing H T Leads. Consists of H.S. Mag used with special Test Plug.
Test Plug. Central Assembly of RS 5 Plug fitted in body of R.V. 7/5 Plug 18 volt plug with the earth electrode removed. Spark voltage 12,000 volts in atmosphere. Cover mouth of plug with fine mesh gauze to prevent fire.
(1) Remove distributor clear of Rotor (2) Disconnect all H T Leads. (3) Attach test plug to lead valve Test. (4) Connect H. T. feed from H. S. Mag to segment of Lead under Test, then earth H. S. mag to engine. (5) Rotate handle of H. S. Mag & if test plug sparks, lead is serviceable. (6) If no spark occurs at plug test all connections before posting lead as U.S.
3% drop in Revs permitted running on 1 plug.
Cowling fitted Eng Temp 190° Cruising 235 Takeoff rev
[Underlined] Checking Cowling Grills for Correct Movements [/underlined]
Should open through a range of 15°. Method of checking & obtaining synchronisation (1) Mount plane in rigging position (2) Set Hand wheel in cockpit to fully closed (3) [Indecipherable word] a clinometer set port & starboard gills to 2°. (4) Connect up chain & cable, open gills by wheel until reading of 17° is obtained, ensure stop on wheel is in place (4) [sic] Adjust eccentric sprocket for slackness in chains. [Underlined] Settings [/underlined] Ground running fully open
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[Underlined] Take off [/underlined] not less than 1/2 open. This may vary. [Underlined] Cruising [/underlined] closed as far as poss in keeping with Cylinder Temp as per data plots. [Underlined] Air Intake Shutter [/underlined] Started in Cold position. Hot air for warming up, low air temp gliding, damp atmosphere, rain, snow, clouds, etc. Checking Shutter. Set Lever to Hot (2) Examine Shutters should be fully closed, if partly open control system is up the spout. Adjust any moving clips which hold Sill crank arms up the mounting arm.
[Diagrams]
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[Diagrams]
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[Diagram]
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1605203
A.G. GOULD
CLASS B
DIRECT ENTRY
F/E 2
Form 619.
ROYAL AIR FORCE.
Notebook for use in Schools.
[Calculations]
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[Indecipherable words]
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[Underlined] [Indecipherable word] of Aircraft [/underlined]
When aircraft is in rigging position Longitudinal Axis is Horizontal. This applies to Lateral Axis.
Normal or Vertical Axis passes through Centre of Gravity
Rolling. Movement about the Longitudinal Axis
Pitching. Movement about the Lateral Axis
Yawing. Movement about the Normal or Vertical Axis
[Underlined] Control [/underlined]
(1) Longitudinal Control. – Control about the Lateral Axis (i.e. control in pitching) effected by means of [underlined] elevators [/underlined].
2) Lateral Control. – Control about the Longitudinal Axis (i.e. Control in rolling) effected by means of [underlined] ailerons [/underlined].
(3) Directional Control. – Control about the Vertical Axis (i.e. Control in yawing) effected by means of [underlined] rudder [/underlined].
(4) Differential Control. – Control which enables the inside aileron on a banking turn to be moved up through a greater number of degrees when the outside one moves down. This can also be effected by the use of Frise ailerons. So that planes are fitted with Differentially controlled Frise ailerons.
[Underlined] Inherent Stability. [/underlined]
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[Underlined] Heat. [/underlined] Tends to produce a rise in temperature in a body When a body undergoes a [underlined] change of state [/underlined] eg. solid to liquid or liquid to gas: there is no change in temperature. Heat in measured in British Thermal Units BTU’s
1 BTU = Amount of heat required to raise temperature of 1 lb of water by 1 degree Farenheit [sic]. e.g. to raise the temperature of 20 galls by 100° F would require 20,000 BTU’s
Temperature is a level
Heat is a quantity
[Underlined] Temperature [/underlined] may be compared with the pressure of a water supply and heat with the quantity of water. We measure temperature by means of a thermometer.
To calibrate a thermometer find the lower fixed point be [sic] standing it in melting ice, the higher point is found by holding it in steam from boiling water. 0° C = 32° F 212° = 100° C
[Formulae]
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[Graph]
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[Graph]
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[Calculations]
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A/C starts from A & flies 200 miles N Scale Drawing
A/C flies 100 miles Course 120° Then 200 miles Course 210° then 300 mile Course 330° How far is A/C from A.
[Diagram]
[Diagram]
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[Underlined] Heat 2. [/underlined]
[Underlined] Solid, Liquid & Gaseous States [/underlined]
Most substances can exist in either of the above states. The essential difference between these states is the way in which the ultimate particles of the substance are arranged.
[Underlined] Solid. [/underlined]
The particles are unable to move except for a slight vibration
[Underlined] Liquid. [/underlined]
The particles are free to move, but are restricted by the presence of other particles.
[Underlined] Gas or Vapour. [/underlined]
The particles move very rapidly, completely filling the vessel containing them, and only slightly effect each other.
[Underlined] Fuel for an Internal Combustion Engine. [/underlined]
Only a liquid or a gaseous fuel is suitable for an I.C.E.
In most I.C.Es the fuel leaves the carburettor as a liquid and enters the cylinder as a gas or vapour.
[Underlined] Latent Heat. [/underlined]
In order to change a Liquid into a Vapour Heat must be supplied, the amount of heat required to change 1 lb of the liquid into vapour is called the latent heat of [deleted] the liquid [/deleted] vaporization of the liquid.
[Underlined] Water. [/underlined] – 536 Centigrade Heat Units
[Underlined] Alcohol [/underlined] – 225 CHU.
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Petrol – 75 CHU’s
In the case of the above liquids vaporization will on at atmos. condition, the necessary heat being obtained from the surroundings. If heat is supplied to the liquid the rate of vaporization increases until finally a temperature is reached at which the liquid boils. A pure liquid has a fixed and definite boiling point at standard ATM
[Underlined] Carburation. [/underlined]
To produce the necessary power in an I C E heat must be produced. This is done by burning a mixture of fuel and air.
The function of the Carburettor is to supply to the engine the necessary mixture of fuel and air.
In practice the time allowed for the carburation process is of the order of 1/300 of a second.
The following factors are responsible for this extremely rapid combustion.
(1) Through mixing of the fuel vapour and the air.
(2) The increase of pressure caused by compression
(3) The turbulence in the charge
(4) Choice of a suitable air-fuel ratio.
Methods of supplying the air-fuel mixture to the cylinders
(1) Direct injection to [underlined] each [/underlined] cylinder during inlet stroke, by a mechanical pump.
(2) Injection of fuel into induction pipe under slight [inserted] Stromberg [/inserted] pressure.
(3) Fuel is delivered into the choke by a discharge nozzle and the necessary pressure required is obtained from the depression.
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[Underlined] Fuels. [/underlined]
Petrol is divided into Hydrocarbons ie. Aromatics and Parafins [sic]
Parafins [sic] have poor and Aromatics good, anti detonation.
Flame rate is amount of mixture burned in [indecipherable word] feet per second.
[Underlined] Variation of Mixture Strength for different conditions [/underlined]
[Diagram]
[Underlined] Thermal Efficiency. [/underlined]
[Underlined] Heat generated to do useful work at 100 [/underlined]
Heat generated by combustion in cylinder.
[Underlined] Process of Combustion. [/underlined]
Petroll [sic] = Hydrogen + Carbon
Air = Oxygen + Nitrogen + Hydrogen.
[Formulae]
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[Underlined] Heat. [/underlined]
1 C H U represents is work done 1400 ft lbs of work
1 B T U represents is work done 778 ft lbs of work
1 lb of Petroll [sic] 18000 BTUs
Pressure Relief Valve
In liquid cooled system there is a tendency for the coolant to boil with increased altitude this is because the heater tank is open to atmosphere and this is decreasing. It is necessary to fix a pressure relief valve in the heater of tank and this keeps the pressure of the boiling point of the coolant 2 to 2 1/2 lbs above normal value that is 30 lb above Atmospheric pressure.
[Graph]
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70% Water 3-% Ethylene Glycol Freezing point – 60° C.
Directorate of Technical Development. Fuel DTD 230
Oil 109.
[Underlined] Mixture Strengths Required. [/underlined]
Fuels consist mainly of [underlined] hydrocarbons [/underlined] such as C7 H16 (Heptone).
Or combustion by H 16 plus 6 oxygen (from air) [symbol] CO2 + H2O (water).
To supply enough oxygen for complete combustion, [underlined] about [/underlined] 14 1/2 lb of air is required for each pound of a [underlined] typical fuel
[Underlined] Economical [/underlined] Cruising.
In practice the time available for the combustion is of the order of 1/300 th of a second, and if the mixture is “chemically correct” combustion is not complete.
To ensure complete combustion a slight excess of air must be provided. The usual mixture used for economicall [sic] cruising is approx. 5% weak.
[Underlined] Detonation [indecipherable words] [/underlined]
Occurs when the latter portion of the charge becomes raised above its [underlined] Spontaneous Ignition Temperature [/underlined]. It results in a [indecipherable word] rise in pressure, which causes the familiar “[indecipherable word]” loss in power: overheating.
Detonation may be prevented by.
(1) Using fuel of as high an antiknock value (ie High Octane) as possible.
(2) High Pressures I e high Compression Ratio & High Boost Pressure tend to cause detonation
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(3) Weak mixtures cause detonation, rich mixtures prevent detonation.
(4) Low revs if accompanied by moderate boost. [indecipherable words]
[Underlined] Electrics. [/underlined]
[Underlined] Amps [/underlined].
[Underlined] Symbols [/underlined]
[diagram]
[Underlined] Units. [/underlined]
Current. [Underlined] Amperes [/underlined] (Amps). An amp is a certain number of electrons per second.
Electromotive Force. (E.M.F.) (Electric pressure – Voltage)
[Underlined] Volts [/underlined]. The emf of a single cell accumulator is always 2 volts
[Underlined] Resistance. [/underlined] Measured in [underlined] Ohms [/underlined] Resistance of a wire depends upon its length, thickness and its material.
The greater the length the higher the resistance
The greater the thickness the lower the resistance
[Underlined] Ohms Law. [/underlined]
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[Diagrams]
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[Obscured word] – anything which causes motion, acceleration or tends to cause motion.
[Obscured word] Weight – lbs
[Obscured word] = F. distance
[Obscured word] Force multip [obscured letters] by distance in which force acts.
Foot lbs. Work done when 1 lb is moved 1 foot = 1ftlb
[Obscured word] Machines. [Indecipherable word] is rate of doing work = ft lb per min.
[Obscured word] [Underlined] Power [/underlined]. – 33,000 ft lb per min 500 per sec.
[Obscured word] Potential / Temperature / Magnetic / Sound.
Kinetic / Electric / Light
[Obscured word] = Work output / Work input
[Obscured word] = Friction and other resistance. output.
[Obscured word] of forces
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[Underlined] Charles’ Law. [/underlined]
The volume of a gas at [underlined] constant pressure [/underlined] will vary with the temperature i.e. for a 1° C rise in temp. the volume will increase to 1/273 of its original volume, this is called the coefficient of expansion of a gas.
[Underlined] Boyles law. [/underlined]
The pressure of a gas at constant volume will very with the temperature.
Thus the two laws in one mean, with a fixed volume the pressure will vary with the temperature
[Underlined] Density Variation with altitude [/underlined]
[Deleted] Sea Level [/deleted] [Underlined] Height Pressure [/underlined]
[Table]
Temperature drops 2°C for every 1,000ft in height.
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[Underlined] Ohms Law. [/underlined] Voltage = Current. Resistance
[Formulae]
[Diagram]
[Underlined] Series & Parallel Circuits [/underlined]
[Diagrams]
Lamps and other components are places in parallel and not in Series because (1) they can’t be switched on & off separately if in series (2) if one component fails all the rest go out of action in series (3) To maintain the current in the circuit an increase in voltage would be necessary for each new component.
[Diagrams]
[Page break]
[Deleted words]
[Diagram]
[Underlined] Ammeter Connections. [/underlined]
To ensure the current is any wire the wire must be broken and the ammeter inserted in the gap i.e. Ammeter in series
[Underlined] Voltmeter Connections [/underlined]
To measure the EMF or Voltage between any 2 points in a circuit, connect the VM to these points without breaking the circuit I e connect V.M in parallel.
[Diagram]
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[Underlined] IGNITION [/underlined]
The region around a magnet is called a magnetic field. Magnetic lines of force can be shown by iron filings and they show the direction of the magnetic force. Close together at the poles, far apart away from the poles, [deleted] this distance apart [/deleted] The number of lines of force per unit area is called the flux, their direction is from N to S and each is a complete circuit.
[Diagrams]
[Underlined] The Magnetic Effect of a Current. [/underlined]
When a current is passed through a wire a magnetic field is produced, the direction is given by the thumb rule. If the hand represents the direction of the field the thumb = direction of current and vice versa.
[Diagrams]
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[Underlined] Electro Magnetic Induction. [/underlined]
Wherever line of force and a conductor or EMF is involved is it. The greater the no of EMF per second the greater the voltage. If an EMF is involved in a wire by a magnetic field the EMF can be increased by (1) increasing coil (2) increasing strength of field 3 Making lines of force and the coil more rapidly
[Diagram] Key closes – Current grows – lines of force radiate and are cut by [indecipherable word] coil.
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[Diagram]
[Underlined] Supercharging. [/underlined]
[Diagram]
[Underlined] Power Weight Ratio [/underlined]
Kestrel 1.87 Merlin 20 1.12 Hercules 11 1.04
Power output depends upon Mech Eff – Thermal Eff – [indecipherable word] Eff – Engine Speed
[Underlined] Reasons for Supercharging [/underlined] To maintain low level [indecipherable word] at Altitude & to increase V. E. To obtain more power at [indecipherable ] Eff I .e more V E.
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[Diagram]
Oil Temperature. Bottle & tube filled with mercury & must be kept clear of all heated parts
Vapour pressure type – Ethyl Ether – Coolant Temperature [underlined] partially filled only [/underlined]
Colour of [indecipherable word] – Oil – Yellow Coolant – Blue Fuel & [indecipherable word] Red.
When fitting instruments start from cockpit & work to engine using brass nuts & bolts & anti vibration washers
Engine temp taken by Thermo Couple consistency of 2 dissimilar metals [deleted words], which generates slight E M F which is measured by Pyrometer which is Mille Volt Meter. Metals Used are Constantin [indecipherable word] Cupro Mickel positive.
[Underlined] Tachometer Drive [/underlined] Driving Cable must not be [indecipherable word] inside a 9” radius. Centrifugal drive. Cable drives at 1/4 Speed stepped up by [indecipherable word] gear to engine speed in instruments. Should not be taken within 18” of Compass.
[Underlined] Telelevel Guage. [/underlined] Fuel Contents
Cable must be wound to top of drum before tanks are filled, to check level turn back until cork float locks on rocket.
This consists of metal or cork float operating up & down a brass tube, inside tanks. In the case of metal float this
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[Calculations]
[Underlined] Torque [/underlined] [Formula]
N.B Force & Arm must be at rightangles [sic].
[Underlined] Drag [/underlined]
[Underlined] Form Drag [/underlined] is sue to the formation of vortices behind the body caused by the action od viscosity. These vortices prevent the fluid from closing behind the body as it opens up in front and so prevents the fluid from exerting the same pressure on the back of the object or on the front. This pressure difference causes drag. Form drag can be reduced by streamlining.
[Underlined] Skin Friction. [/underlined] is due to turbulence in the boundary layer. Surface roughness (I e rivets) paint with matt finish fabric etc causes increase in skin friction.
[Underlined] Induced Drag. [/underlined] is due to wing tip vortices and can be reduced by proper shaping of the wing tips and by using high aspect ratio
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[Underlined] Retonation. [/underlined]
As charge burns temp & press increase – unburnt portion is compressed by burnt portion & its temp is raised by compression. If the rate of temp increase is too high spontaneous combustion will occur [symbol] [indecipherable word] rise in pressure in this part of the charge. If rate of burning is fast – no increase in volume and it is poss. to get a local pressure of 1 Ton [symbol]. This high pressure causes a shock or wave, which strikes the cylinder walls and causes a knocking sound.
[Underlined] Harmful Effects [/underlined].
(1) Rise in temp on piston crown. (2) Max stress on Material due to excessive temp & pressure. (3) Alloy of piston and crown worn away by excessive scarring. (4) Excessive loads on bearings may cause a breakdown of lubrication.
[Deleted number] [Underlined] Factors & Causes of Retonation [/underlined]
(1) Excessive Boost Pressure (2) Too high a [indecipherable word] Ratio (3) Nature of fuel. (4) Turbulence (5) Poor shape of cylinder.
[Underlined] Exhaust valve difficult to cool.
[Underlined] Exhaust Gas Analysis. [/underlined]
[Table]
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Limit of Dope 4 cc per gallon.
[Underlined] Octane Number. [/underlined]
The reference point for Oct is a mixture of 81% Iso Octane & 13% Normal Heptane. If the fuel under that has the same resistance to detonation as the ref fuel above its Octane No. is said to be 87. [symbol] 100 Octane is equivalent to [indecipherable word] book value 100% for Octane & No per cent Normal Heptone.
Latent Heat of British Petrol averages 135 BTU’s per lb.
[Underlined] Requirements of Good Air Craft Fuel [/underlined]
(1) High Calorific Value (2) Hish Anti [indecipherable word] value (3) Good volubility. (4) High Latent Heat of Vaporization (5) Low Freezing Point (6) High Specific Gravity (or [indecipherable word] of G at any altitude) (7) Low Gear & Acid for test.
[Underlined] Heat 5 – 6. [/underlined]
[Calculations]
Ht Energy = 1 BTHU
Mech Energy = 778 ft lb [indecipherable word]
1 gall/min 7.2 lb.
Max En Cruising 7.2. 18000 BTU
Work done 7.2. 18000. 778 ft lb.
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Work done in cylinder [calculation]
[Calculations]
[Formulae]
[Calculations]
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[Underlined] Effect of High Temp on Cylinder. [/underlined]
(1) Softening (2) Loss of [indecipherable word] (3) Erosion. These will detonation, temp rise may be by 2,000° [symbols] great necessity for Cooling (1) Piston (2) Cylinder Walls (3) Cylinder Block
[Diagram]
[Table]
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From figures it can be seen that with constant RPM & constant Boost, R.A will be [indecipherable word] in M Gear when the Boost after RA has fallen [underlined] by [/underlined] +2 change to S Gear then switch RA in S Gear this is full throttle height with constant RPM & Constant Boost, if greater full throttle height needed increase R.P.M.
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Drag – Made up of Active – Parasite – Interference Drag.
Active from lifting surface Parasite from Non lifting surfaces Interference from point/surface [indecipherable word] another
Active & Parasite Drag can be divided in Form + Skin Friction Active for also Induced drag.
[Diagram]
[Underlined] Form Drag [/underlined] is due to slope & angle of attack of the object. Reduced to & [indecipherable word] by Streamlining.
[Underlined] Skin Friction [/underlined] is due to the roughness of any exposed surface & the Viscosity of the air. This is reduced to a minimum by making all exposed surfaces as smooth as possible. {polishing – flush [indecipherable word]).
[Underlined] Induced Drag [/underlined] is due to wing tip vortices. Reduced to a minimum by having an Aspect Ration ( [indecipherable words] as large as possible.
Relationship between drag & Air-speed.
Drag depends upon air speed; i.e. the speed of the object relative to the air in which it is moving. If the airspeed is doubled then the drag us more than doubled, it is multiplied 4 times. (The speed squared.)
[Table]
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Relationship between Drag & Air Density.
Drag is proportional; to Air Density.
If the Air Density is doubled, then, other thins being equal, the drag is doubled.
[Formulae]
[Calculations]
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[Calculations]
I H P = PLANE [symbol] 33000
P = Mean effective pressure (lb [symbol]”)
L = Stroke in ft
A = Area of [indecipherable word] ([symbol] “)
N = No of Cylinders [deleted letter]
E = No of Explosions (Power Strokes) [formula]
[Underlined] F 5 [/underlined]
As density of air decreases drag decreases. Venturi Principle. Increased speed of flow through a neck us accompanied by a decrease of pressure in the sides. [Diagram[
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[Calculations]
[Underlined] Example] [/underlined]
An Engine rotates a flywheel of 4 ft diameter against a force of 2000lbs. Find (a) Torque (b) BHP developed at 1000 RPM.
[Calculations]
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[Formulae]
[Underlined] Centre of Gravity [/underlined]. (C.G.) us the point at which the resultant weight of an object may be considered to act.
An object will balance about its centre of gravity. C.G. is the point at which the resultant turning effects (moments) cancel each other.
[Formulae]
[Underlined] Landing Speeds. [/underlined]
For a given landing C & S. are [indecipherable word] and [formula] must be kept equal to the weight of the aircraft. In order to decrease V, CL must be increased by increasing the angle of attack. The angle of attack cannot be increased beyond the stalling angle. (The speed corresponding to the stalling angle is called the stalling speed.
[Underlined] Slats. [/underlined]
If a properly [sic] slat is placed in front of the main wings with a suitable slot in between the angle of attack can be increased beyond the normal stalling angle before the airflow breaks up over the top surface this means an increased
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Lift coefficient and therefore a lower stalling speed.
Disadvantages of Slats.
The fuselage must be tilted at a large angle giving poor visibility from the pilot’s cockpit and necessitating a high & [indecipherable word] undercarriage.
[Underlined] Flaps. [/underlined]
Flaps, like slats, cause a decrease in the stalling speed, but only the flap needs to have the angle to the airflow increased. So that the a/c need not be so high and the pilot has a better view. The increased drag reduces the excess speed (Landing speed – stalling speed) more quickly
[Underlined] Carburation. [/underlined]
Weak – Econ Cruising 16:1 [underlined] not with high boost [/underlined] } [indecipherable word] + Main Jets
Chemically Correct – 15:1 }
Rich – Power 13:1 }
Rich – Slow Running – S.R. Jets
Rich – Rated Condition – Max Climb – 12:1 – Power Jet
Rich – Takeoff – 11:1 – Enrichment Jet
Deceleration – Accelerator Pump & Delayed Action Pump.
Altitude Mixture Control
Corrected Jet C.H. supplies fuel ‘into’ the diffuser above the Main Jets.
Lift depends on (1) Lift coefficient (- a number depending on shape & angle of attack. (2) [Underlined] Plan [/underlined] area of lift surface (3) Air density (4) Air speed.
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[Diagrams]
[Underlined] Angle of Attack. [/underlined] Angle between Cord [sic] line & Flight Path.
[Underlined] Angle of Incidence. [/underlined] This is the rigging angle. It is the angle between the Cord [sic] Line& the datum line.
[Underlined] Stalling Angle. [/underlined]
Angle of attack at which the lift is a maximum.
[Underlined] Optimum Angle [/underlined] Angle of attack at which the lift-drag ratio is maximum. At the same time, the drag of the whole aeroplane is at a minimum. Thus, it is the most efficient angle of attack. And thus an aircraft will therefore cruise most economically in this angle.
Relation between speed & angle of attack. If the speed of an aircraft is increased the lift developed will increase and the aircraft will climb. If the speed is decreased the lift
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Developed decreases and the aircraft will lose height. [Symbol] If it is required to stay at the same altitude, as the speed is increased the angle of attack must decreased [sic] and vice versa. For each angle of attack there is only one speed for steady horizontal flight, and the slowest speed will be the aspect at the stalling angle. i.e. the stalling speed.
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[Blank page]
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[Calculations]
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[Underlined] MERCURY SERIES [/underlined]
9 Cylinder Air Cooled Radial Supercharged Bore 5 3/4“ Stroke 6 1/2“, Compression Ratio 6 1/4 – 1 Reduction Gear Ratio Mercury 8 & 8A .572 – 1 Direction of Rotation of Airscrew Shaft Left hand from rear – anti-clock. D of R of Crankshaft Left hand Supercharger Gear Ratio 9.4 – 1 Dry Weight Mercury 8-1002 lb.
Cylinder Numbering ([indecipherable words]) anti-clock No 1 vertical.
Fuel – L & R 230 (87 Octane) Oil – D 7 D 109 pure mineral oil.
Pump pressure – Normal 80 lb [symbol]” Minimum 5 minute limit – 65lb [symbol]”.
Consumption 6-12 pints per hour at 2400 RPM. Inlet oil temperature Maximum for takeoff (high initial oil pressure device in operation) 5° C.
Max for continuous cruising 70° C. Max for climbing 80° C. Emergency Max (5 minute limit) 85° C.
[Underlined] Ignition [/underlined]
Firing order 1-3-5-7-9-2-4-6-8. Ignition Type 2 Watford SP – 9/4 1 290 single contact breaker or SP 9/6 35 twin breakers. D or R anti clockwise 9/8 engine speed. Timing – Tally advanced 35° B.T.D.C. Ignition control – automatic advance & stand.
[Underlined] Carburettor [/underlined] AYT 85 E
[Underlined] Valve Timing [/underlined] Inlet opens 29° BTDC Inlet closes 47° ABDC Exhaust opens 76° BBDC Exhaust closes 40° ATDC [Underlined] Valve [/underlined] clearances cold, Inlet 4 close, Exhaust 6 close. Starter system Load & electric timing gear. Airscrew variable pitch.
[Diagram]
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[Diagrams]
Only 1 main bearing Steel shell – nickel alloy or white metal outside.
[Calculations]
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[Underlined] 9 Cylinders [/underlined] 1-3-5-7-9-2-4-6-8 – 40° difference between each stroke
(1) 70 C Compression (2) 40° BTDC EX (3) 80° BIDC COMP (4) 60° ABDC EX (5) 20° ABDC COMP (6) 20° BBDC. POWER (7) 60° BBDC IND (8) 80° ATDC POWER (9) 40° ATDC INDUCTION.
[Underlined] [Deleted words] [/underlined]
Lower Cylinder Tappets below Centre Line of Engine consist of Oil Sleeve Gets Spring Loaded Leather Oil Seal 2 Holes in Oil Sleeve line up with 2 Holes in Carb [indecipherable word] Upper Tappets have no oil sleeve but have Seal. Carbon Steel Task Rods Hollow Steel hardened at ends. Tappet wheel mounted on fully floating bush and fully floating pin.
[Diagram]
[Underlined] Reduction Gear [/underlined] To find reduction find no of teeth on Driver & Drive. [Formula] Driver 60 teeth [indecipherable word] 50 teeth Reduction [formula]
Collector Ring Fitted in front of Fixed Bevel to supply oil to A/S. Bearings – Air Starter Thrust, Bevel Pinions Centrifugal - Rear Bearing – Tendency of Bevels to separate.
[page break]
[Underlined] Duplex – Spring loaded Vanes – fuel Pump. [/underlined] 250 galls P.H. 2500 R.P.M.
[Indecipherable words] rotors in steel lined housings having 4 vanes
[Diagram]
[Underlined] Bristol High Metal Oil Pressure Pump. [/underlined] 80lb [symbol]” 600 galls p.h.
[Page break]
[Underlined] Magneto Timing - Mercury. [/underlined]
(1) Using a P.P.I find T.D.C. (Compression Stroke) on [underlined] No. 6 [/underlined] Cylinder
(2) Set Timing Plate in position and turn engine back so that [underlined] No 6 [/underlined] piston is [underlined] [deleted] 25° [/deleted] BTOC Compression. [/underlined] 29° [underlined] SP 9/4 [/underlined]
(3) Prepare mag as follows :- Insulate the Primary Winding – Set C. B. points to [underlined] .012” [/underlined] – Fully advance magneto – Turn mag until rotor is opposite [underlined] No. 6 [/underlined] segment and the C/B points are just about to open.
(4) Line up degs on magneto to slots in drive and fit mag to engine.
(5) Check with lamp and battery and make adjustment where necessary on the fine adjustment (1 Serration = 2 crankshaft degrees) Timing to within 1°.
(6) Repeat on other mag and test both mags for synchronisation to 1°.
(7) Remove mags and :- Remove insulation – Remove advance clips – Insert split pins in fine adjustment nuts.
(8) Replace mags on engine.
[Page break]
Mercury Lubrication – Dry Sump – 80lb [symbol]”
Component lubricated by High Pressure – C/S Tailshaft Bearing – Big End Bearing (Start shell White Metalled freely drilled) – Con Sleeve bearing – Air Screw Tail Shaft Bearing – Bevel Pinion Bushes – all the bushes in Rear Cover – [underlined] Wrist Pins [/underlined] Cross Drive Shaft plain bearing lubricated at 80lb [symbol]” – BTH Air Compressor bearing – Tacometer – Fuel Pump.
Hand Priming & Greasing.
- On Installation or period of standing exceeding 5 day The nipple at the front of the new cover. [Indecipherable word] new [deleted word] Supercharger bearing – Nipple between 1 & 2 cylinders To lubricate front S-chgr & gears (Spring [indecipherable word] Used) Nipple on end of cock rocker arm. Lubricate revolving button of valve mechanism. Grease nipple at rear of rocker box. Lubricating the rocker arm ballbearing.
[Underlined] Felt Pad. [/underlined] The Inlet Push Button Inlet Rocker arm buttons positioned to front of rocker box cover.
[Underlined] The Felt Pad [/underlined] fastened inside Rocker Pad lubricate Exhaust push rod button & Rocker arm buttons. Felt washer lubricate vale stems & ends. Attached to end of each valve.
[Underlined] Splash Lubrication. [/underlined]
All ball & roller bearing are lubricated by Splash Oil. Main Forward Roller Bearing, ball Rise in front cover Back thrust occurs in revolution gear & 3 [indecipherable words] on the bevel pinions and Ball Bearing to Gravity Drive. Intermittent feed to Supercharger bearings. These bearing
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receive a squirt of oil every revolution of the Crank shaft.
Cylinder Walls – [indecipherable words] First Bellow lubricated by splash oil flung about within Crank core. All scavenge oil drain into sump between 5 & 6 cylinders, mostly Internally by internal pipe from next cover. The oil is sucked from the sump and the scavenge filter around the pump gears & by external pipe to Carb Gasket and then back to tank run above & cooler, H. I. O. P. drive supplies extra pressure to engine system when starting from cold and sprays oil onto big end assembly area [indecipherable word] between 1 & 2 cylinders & automatically cuts itself out when temperature of oil increases to a given figure. Feed to supercharger is intermittent and is high pressured by way of the C/S T/S through a duct into the aluminium tube which links up with a duct once easy revs.
[Underlined] Cooling. [/underlined]
Fins – Baffles (Inter-Cylinder) – Cowlings Gill Ring Fins increase surface area. Baffles direct airflow round cylinder
[Diagram]
[Page break]
[Diagram]
Valve Timing. Tappet Clearances. Inlet 4/000 6/000
Finding the duell [sic] inlet No 6 Cylinder to TDC Compression (2) Set Tappet Clearances to 4/000 Inlet 6/000 Exhaust using [underlined] 2 [/underlined] sets of feelers. (3) Rotate Crankshaft in 1 OR [underlined] 2 [/underlined] revs. (This moves [indecipherable word] sleeve 90° in [indecipherable word]) bringing next [indecipherable word] onto No 6 cylinder. (4) Check No 6 tappet clearances and note. (5) Repeat the above for the other 2 [indecipherable word]. (6) The [indecipherable word] giving the smallest tappet clearance is the highest and all valve clearances must be set by the highest [indecipherable word] [deleted letter] or [indecipherable word].
[Underlined] Setting valve Clearance. [/underlined]
(1) Turn engine till highest [indecipherable word] (Inlet or Exhaust) is opposite no 6 cylinder and set tappet clearance. (2) Rotate Engine in D. O. R. 320 degrees (1 rev less 1 cylinder space) and set tappet clearance on No 5 cylinder. (3) Repeat for the other cylinders as above.
[Page break]
[Underlined] Piston Rings [/underlined]
[Diagrams]
No. 6 ring cut square to [indecipherable word] oil in cylinder, Pitted to distinguish
[Underlined] COMPONENTS. [/UNDERLINED]
Header Tanks. Thermostats. Radiators.
[Diagram]
[Page break]
Coolant Tanks made of Sheet Brass – Lagged & Baffled to prevent surge & strength of sides. [Indecipherable word] Vortex device fitted to precast in Cock. Coolant under 30 lb [symbol]”.
2 Way relief valve [inserted] duplex [/inserted] opens at 30lb [symbol]” to reduce pressure – opens inward at – 1/2 lb to maintain 14.7lb [symbol] in tank. [symbol] [Underlined] Simple type. [/underlined]
[Diagram] Thermostatic Heater Relief Valve.
(1) To permit pressure to build up in the cooling system in order to raise the boiling point of the coolant and so increase its capacity to absorb heat from the engine.
(2) To act as a safety valve to prevent the building up of excessive pressure. (3) To admit air to limit the negative pressure in the system when the engine stops. (4) To provide an escape valve for any [indecipherable word] gas that may exist in the cooling system.
[Underlined] Functioning [/underlined]
(1) When cold the thermal element cage is held down by the light spring on the top of the stop plate so closing the valve and depressing the vacuum bellow slightly.
(2) During the initial warming up, expression of the engine coolant causes positive pressure in the vacuum compartment raising the vacuum bellows into contact with the stop plate and if the pressure increase exceeds 2 1/2 lb [symbol]” in the valve will be opened, lifting the thermal cage against the light spring and so relieving the pressure.
(3) Further warming expands the thermal bellow until at 100°C the main spring abuts against the adjuster plug and becomes
[Page break]
the internal and external pressures are equal the valve is in a state of balance and the total reaction is taken by the main spring.
(4) Further rise in engine temperature expands the bellow fully up to the thermal cage until it overcomes the compression of the main spring whereon the valve lifts and sets as a relief valve, operating at a pressure of 30lb [symbol]”.
(5) On Cooling, the system loses pressure until a partial vacuum is formed: the vacuum allows this contrast to open up the valve and to [indecipherable word] with atmospheric pressure.
Thermostat } fitted between heads & Rotator [inserted] 15 galls per min [/inserted]
Terrington } A coolant radiator.
[Underlined] Operation [/underlined]. When the coolant is cold the compressed air bellow keeps the radiator valve load on its seating so that no coolant can flow through the radiator. This reduces the time necessary for warming up from cold. As he engine warms up a vapour pressure is created in the [underlined] Thermo Bellow [/underlined], and at approx. [underlined] 85°C [/underlined] this pressure overcomes the pressure in the [underlined] Compensating bellow [/underlined], forcing the radiator valve off its seating. [Underlined] At 105°C [/underlined] the radiator valve is fully open, and bypass valve is closed. Should the [underlined] compensator [/underlined] become punctured then the radiator valve would open at very low temperature. While this would tend to overheat the engine it would cause no [underlined] damage. [/underlined] On the other hand failure of that thermal bellow would cause radiator valve to shut permanently and engine to overheat and seize. To avoid this risk the third bellow is fitted, incorporating a coil spring and steel spike. Failure of the Thermo balloon would cause this to be [indecipherable word] to puncture Compensator Bellow forcing Radiator valve fully open. Test by
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inserting in hot oil and raising to required temperature. When drawing from stores look to By Pass port to see if BP. Is open. If bonded with yellow do not use with 100% Glycol.
[Underlined] Jointing. [/underlined]
High pressure rubber jointing – with special metal clip. White rubber coolant. Red rubber fuel system.
[Underlined] Radiator. [/underlined]
Honeycomb type – Galley type (Cupro Nickel alloy – Glycol resisting) Cleaned with hot water 2° [indecipherable words]
[Underlined] Oil Tank. [/underlined]
Never clean with paraffin – flush with flushing oil.
[Underlined] Hoywood Air Compression [/underlined]
Viscosity Valve ([indecipherable word]
[Diagram]
[Page break]
[Underlined] Viscosity Valve. [/underlined]
This valve is designed to prevent the oil congealing during long glides or overheating under full power ops in climb.
Oil from the engine flows into a chamber which is closed by two valves - one being a control valve – and the other a spring loaded relief valve. In this chamber directly in the path of the oil flow is a small filter through which a [underlined] sample [/underlined] of oil is passed through the head of the valve into the viscosity pressure chamber. When the oil is cold of viscous the sample of oil will pass through the filter but will not pass through the friction tube & pressure is built up inside the Control Valve which holds the valve on its seat and surpasses the pressure of the spring loaded relief valve. The relief valve is forced open & oil goes direct to the Oil Tank.
As the oil becomes less Viscous the pressure inside the Control Valve drops, due to the fact that the oil can escape more easily through the friction tubes, this results in the total pressure in the control valve becoming less than the spring pressure behind the by pass valve, causing the by pass valve to start closing & control valve to start opening, thus permitting the oil to flow through the cooler.
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[Underlined] OIL DILUTION SYSTEM [/underlined]
[Diagram]
[Underlined] Filters [/underlined] Maintenance – Isolate from oil circuit (cocks) – Remove drain plug [deleted word] and catch oil in container. Remove container by enclosing the set screws at the head. – Lift out the filter, reserve the wing nut & end plate. Remove the gauge from perforated cylinder Clean all parts with petrol. Replace filter gauge with new one or scrub in [underlined] parafin [sic] [/underlined]
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[Diagram]
[Underlined] Hydrostatic Fuel Contents Gauge. [/underlined]
Principal of operation. The weight of the load of fuel on the bottom of any tank exerts a hydrostatic pressure in proportion to the load of fuel [indecipherable word] of pressure gives indication of load of fuel in tank. The transmitting box capsule assembly capacity tube and indicator diaphragm from a sealed system filled with nitrogen at a predetermined pressure. Pressure of fuel on capsule assembly in transmitting box is conveyed by way of capillary tube to capsule is indicator the expansion of this capsule is measured then indicating fuel in tank
Rotary Float Fuel Contents Gauge.
[Diagram]
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[Table]
[Diagram] All Capiliary [sic] tubing [underlined] (Surplus) [/underlined] must be coiled in a diameter not less than 6” and secured with at least 3 clips.
Oil pressure to [indecipherable words] Capsule & C Tube filled with Ethyl Alcohol.
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[Underlined] Amel Fuel Pressure Reducing Valve. [/underlined] Reducing valves are necessary in order that the correct pressure is maintained at the earth. The pressure is standardised at 1.9 lb [symbol]” irrespective of delivery pressure. [Underlined] Operation [/underlined] A spring loades [sic] diaphragm is opposed by a piston and conical valve. The piston valve controls the fuel pressure and the conical valve comes into operation when the piston valve covers the ports and cuts off the flow of fuel. Provision is made for the conical valve to operate independently in case of piston valve sticking. Pressure is built up against a spring loaded diaphragm, pushing it up and allowing these valves to open or close regulating pressure of fuel. [Underlined] Installation. [/underlined] Must be fitted within 1 foot of [indecipherable word] and should be fitted horizontal or at an angle of not more than 45°, but can be mounted upside down. [Underlined] Maintenance. [/underlined] The drain plug should be removed & valve flushed out when fuel filters are cleaned. At Major inspections valve must be dismantled and examined for damage & defects, defective parts should be replaced with new ones. Diaphragm must be replaced every 1000 hours running time. Test at pressure of 2 lb [symbol]” with outlet pointing downwards a leak of only 1 drop per minute is permissible.
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Boost Pressure.
This is the pressure [underlined] above [/underlined] or [underlined] below [/underlined] Atmospheric [underlined] whatever the altitude [/underlined]. eg. 10,000 ft At Pr = 10lb [symbol]” Boost= +6 Boost Pressure = 14.7 + 6 = [underlined] 20.7 [/underlined]
[Underlined] Rated Altitude. [/underlined]
Greatest height in Standard Atmosphere at which engine can maintain Rated Boost at International RPM.
Rated Boost is Maximum Climbing.
60 miles per hour = 88 ft per second
Work done in 1 min = Drag in lb. speed in mph. 88
[Calculations]
[Underlined] Power [/underlined] = Rate of doing work = Work done/Time
550 ft lbs per second or 33,000 ft per min = 1 H.P.
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tube is fitted with a rachet so that when tank is empty the float can be moved up & down the column by means of a Bowden Cable which is housed on a dural drum inside the gauge operated by a butterfly handle mounted in centre of gauge dial. The rachet operates only when the float comes up against level of petrol. The float then takes up a horizontal position and the fixed tooth on the float engages with the rack on the tube or column & becomes locked, at [sic] it remains so until the petrol level drops & rebases the float from the horizontal position.
[Underlined] Flexible Pipes. [/underlined]
Petroflex, Superfloat, Arioflex, Duraflex.
Graphite grease on alloy nuts.
Pipes & Pipelines
Flexible Fuel Pipes. These pipes must be examined for chafing and must be properly supported against vibration, if the pigmentation has been chafed the pipe must be treated with seaplane varnish and protected with thin sheet cork. Flex pipe between filter & Carb only are stamped with date of manufacture, if date is 3 years or over pipe is U.S. When fitting avoid sharp bends & when tightening nuts care must be taken not to twist tubing, which would break internal spiral & cause restriction in pipe, do not overtighten & strip threads.
Petroflex, old type pipes have a rear [indecipherable word] & are not electrically bonded, they are fitted with a bonding eye for this purpose, this tubing is now made in two types, Low Pressure for fuel systems + High Pressure for Air + Oil systems.
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which will withstand [inserted] working [/inserted] pressures up to 700 lb [symbol]“ or 60° C. This pipe consists of an inner tube made of hog or horse skin, the gut core is covered with 2 ply cotton fabric. The tubing is reinforced with two spirals of wire, one internal and the other outside. The tubing is electrically bonded and the outer surface is protected with pigmented oil varnish Superfluid. This tubing is used in fuel and certain oil systems. The core consists of a Cellulose film, and a brass wire spiral, wrapped with layers of cotton. This is followed by rubber sheeting, the tube is finished by either a metal braided outer cover or a covering of fabric reinforced with a spiraly round wire.
[Indecipherable word] Used in air and oil systems. This tube consists of an inner core of flexible metallic tubing, over this a rubber tube is vulcanised and not wrapped. The whole is protected & reinforced by strong metallic braiding.
[Underlined] Duraflex [/underlined] Use in Air & Oil systems. Duraflex is similar in construction to the above, only more robust being 2 steel wire braids instead of one. Working pressure 1,200lb [symbol]”, at max temp of 120°C.
Fitting of end connections of all flexible types.
The end connection & couplings are designed to [indecipherable word] with A G S fittings. Where fitting new coupling, reference should be made to (A.P. 1464 A, Volume 1 Part 5 Section 5).
Protective Covering for rigid fuel pipes
Rigid fuel pipes are in certain circumstances provided with a protective covering similar in principal to that fitted to fuel tanks the covering is safeguarded against leakage of
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fuel when the pipe is fractured or holed and consists of a spirally wound layer of canvas strip solutionised to the pipes over which 2 layers of specially prepared rubber strip are applied longitudinally the whole being wound in as outer cover of spirally wound canvas. The selfsealing action is afforded by the local swelling of the rubber when it contacts the fuel, the rubber being encased in canvas is forced into the crack or hole and effectively prevents further leakage.
Selfsealing Flexible Tubing is now available for fuel pipe lines up to 1 1/2 “ bore, 2 types are now in use Type A for internal pressures up to 5 lbs [symbol]” B for 15 lb [symbol]”. In addition to selfsealing, the outer layers are treated for protection against fire. No metal is used in the construction of this tubing, the internal strength being obtained from a hellically wound plastic strip, this strip prevents the tubing from kinking at bends and when hit by a bullet it fractures with a minimum injury to the pipe this tubing is not to be used where temperatures exceed 70°C. [Underlined] Identification [/underlined] Type A Red Type B Red with Black Hellical Bands.
Rigid Pipes (Copper)
All Copper tubing used on aircraft is issued in its fully annealed condition. This Tubing had to be heat expanded or shaped in its cold state using only a fusable alloy which melts at 100°C (Boiling water). Pipes must not be rebent after use owing to fracturing propensities. When incorporating a rubber coupling to a copper pipe the ends must be first beaded
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and then tinned. The pipe must then be bonded with a tinned copper bonding strip. On Bristol Engines on oil pressure side an additional centre clip (Jubilee) must be fitted to restrain the swelling of the coupling. [Underlined] [Indecipherable word] [/underlined] Tubing must be treated in exactly same way as copper – cold shaped bonded – tinned protective packing for this pipe is brass gauge (80 mesh).
[Underlined] Stainless Steel. [/underlined]
No attempt must be made to bend or alter the setting of these pipes – when damaged ref must be made to schedule of spare parts and a new pipe ordered, as a temporary measure a copper pipe may be fitted. To protect S S pipes paint the ends in contact with rubber coupling with an air drying enamel coating the rest of the pipes with seaplane varnish, for bonding us [sic] SS strip [underlined] only [/underlined]. [Underlined] Light Alloy pipes [/underlined] are used for vent pipes for tanks not for conduits for leads & cables and are also used on some fuel oil & coolant pipes.
[Diagram]
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[Diagram]
1. Electrical Contents Gauge 2. Air Vents 3. Suction Balance Cocks 4. Delivery Balance Cock 5. Non Return Valve 6. Filters 7. Mechanical Tail Pumps 8. Priming Pumps 9. Pressure Gauges 10. Isolating Cocks 11. Drain Cocks 12. Carburettor. Pressure Side [symbol] Gravity Side [symbol]
3 & 4 closed during normal running. Vent pipes should be examined by uncoupling from tank and air pressuring. Taking care not to blow dirt into tank.
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(1) Before opening up the engines before takeoff (a) Both tank cocks should be open (b) Balance cocks in pipes which connect [obscured word] system on suction & delivery side are to be kept closed and only opened in emergency such as the suspected failure of fuel pump on 1 engine. (c) fuel pressure gauges should show the pumps are working
(2) Normal Flight (a) both Tank cocks should open (b) both balance cocks should be shut.
(3) If 1 tank is damaged (a) Open suction pipe balance pipe and shut off undamaged tanks to use as much as poss from damaged tank (b)When tank is empty close cock to damaged tank and open cock to undamaged tank, leaving suction balance cock open & delivering balance cock shut. Damage to a tank is shown by visible escape of fuel or by abnormal consumption as shown on fuel contents gauge.
(4) If one engine pump fails open suction and delivery balance cock. by this action the pump undamaged will supply both engines from both tanks. failure of a pump is indicated by a fall in pressure on fuel pressure gauge.
(5) If One Engine fails open suction balance cock only the engine which continues to run will then draw its supply of fuel from both tanks but fuel will not be delivered by the pump to the engine which has failed.
(6) If one tank & 1 pump fail (a) Open both suction & delivery cocks (b) shut off damaged tank. (c) Close cock of damaged tank when empty & open each of undamaged tank leaving both balance cocks in open position.
(7) Both pumps fail the fuel supply will be maintained by gravity.
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[Copy of following page mostly covered with blank paper]
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until tanks are practically empty, if 1 tank is not supply correct amount of fuel open 1 Suction Balance Cock.
[Diagram]
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E G 174 = Inhibiting Fuel.
Starting M C to Rich Air intake [deleted word] cold
[Underlined] Electrical fuel contents gauge. [/underlined]
[Diagram]
Alter reading on gauge be [indecipherable word] soft Iron Core breaks down strength of the different cock
[Underlined] Identification [/underlined]
Oil Pressure – Yellow Beazel [sic]
Oil Temperature Orange Bezel
Fuel Pressure } Red
Boost Gauges }
Coolant Temperature Blue.
Oil Temperature [indecipherable word] Steel - Copper [indecipherable word].
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[Deleted numbers]
Ignition
Testing H T Leads. Consists of H.S. Mag used with special Test Plug.
Test Plug. Central Assembly of RS 5 Plug fitted in body of R.V. 7/5 Plug 18 volt plug with the earth electrode removed. Spark voltage 12,000 volts in atmosphere. Cover mouth of plug with fine mesh gauze to prevent fire.
(1) Remove distributor clear of Rotor (2) Disconnect all H T Leads. (3) Attach test plug to lead valve Test. (4) Connect H. T. feed from H. S. Mag to segment of Lead under Test, then earth H. S. mag to engine. (5) Rotate handle of H. S. Mag & if test plug sparks, lead is serviceable. (6) If no spark occurs at plug test all connections before posting lead as U.S.
3% drop in Revs permitted running on 1 plug.
Cowling fitted Eng Temp 190° Cruising 235 Takeoff rev
[Underlined] Checking Cowling Grills for Correct Movements [/underlined]
Should open through a range of 15°. Method of checking & obtaining synchronisation (1) Mount plane in rigging position (2) Set Hand wheel in cockpit to fully closed (3) [Indecipherable word] a clinometer set port & starboard gills to 2°. (4) Connect up chain & cable, open gills by wheel until reading of 17° is obtained, ensure stop on wheel is in place (4) [sic] Adjust eccentric sprocket for slackness in chains. [Underlined] Settings [/underlined] Ground running fully open
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[Underlined] Take off [/underlined] not less than 1/2 open. This may vary. [Underlined] Cruising [/underlined] closed as far as poss in keeping with Cylinder Temp as per data plots. [Underlined] Air Intake Shutter [/underlined] Started in Cold position. Hot air for warming up, low air temp gliding, damp atmosphere, rain, snow, clouds, etc. Checking Shutter. Set Lever to Hot (2) Examine Shutters should be fully closed, if partly open control system is up the spout. Adjust any moving clips which hold Sill crank arms up the mounting arm.
[Diagrams]
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[Diagrams]
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[Diagram]
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Collection
Citation
A Gould, “Notebook,” IBCC Digital Archive, accessed December 6, 2024, https://ibccdigitalarchive.lincoln.ac.uk/omeka/collections/document/28708.
Item Relations
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