Cash book but contains notes on: medicines/chemicals on first page. Followed by general notes and outline diagrams on Stirling, Halifax, Me-110, Dornier 215 & 217 and Hudson aircraft. Continues with flight engineer's notes on a large number of various miscellaneous aircraft systems and engines.





Notebook with handwritten entries


IBCC Digital Archive


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[front cover of notebook]

Cash Book

[page break]

[inside cover]

[page break]

Tear Group

CAP (NAP) Vapour gas. - Training.

KSK (SP) Peardrops. Red Colour. Liquid.

BBC (P) Slightly persistent liquid gas.

Mustard & Cress. 38 times as persistent as Mustard gas.

[underlined] Nose Group. [/underlined]

[underlined] Arsenical Smokes. [/underlined]

DM Solids. Invisible. Delayed effect.



Toxic Group

Arsenic (NP) Highly inflamable. [sic] Fatal

smell of acetylene gas.

[page break]


[page break]

[underlined] Stirling 1 & 2 [/underlined]

Long range heavy bomber. Heaviest bomb load.

Mid Wing 4 eng. Monoplane

S F & R + Ret Un. C.

Mark I Bristol Hercules 1400 hp. 285mph

Mark 2 Wright Double Cyclone 1600 hp. Greatest Bomb load 7 - 8 tons. Range 2000 miles. Armaments 6 - 10 Mgs. 2 in nose POGT. 2 in tail POGT. others in fuselage, dustbin or dorsal turret

[page break]


nose, long, blunt point staggered engines extend 1/3 to tip of nose.

[three sketches]

[page break]

[underlined] Halifax [/underlined]

Long range H bomber

mid wing

twin fins & R.

merlin In line engines 1375 hp Over 300 mph. 1500lbs? bomb load

8 - 12 Mgs. Underslung engines.

Four in nose POGT 2 in Dorsal POGT 4 in Rear POGT

[page break]

[three sketches]

[page break]

[underlined] Mess 110 [/underlined]

Long range night & day fighter. 550 - 700lbs bomb load. Low firing E. mono 2 f & r.

Engines Daimler-Benz 1150 hp 365mph

Armaments 4 mgs in nose. 2 cannons under under 1 m.g. firing aft.

[page break]

[four sketches]

[page break]

[underlined] Dornier 215 & 217 [/underlined]

Long range heavy bomber. High wing twin engine twin F & R’s

Engines. In line Daimer Benz 1150 hp. about 300mph

Bomb load about 1600lbs. modification Do17 flying pencil

Armament 6 moveable mgs 2 in nose, 2 firing aft & 2 in belly. Long glazed blunt pointed nose.

when dive bombing

[page break]

[underlined] 215 [/underlined]

[four sketches]

[page break]

[underlined] 217 [/underlined]

Long [underlined] range heavy [/underlined] bomber also used as dive bomber. Construction same as 215 difference in engines.

Engines B.M.W 1600hp. radial 325 mph. Max speed.

Armament varies slightly. 4 moveable mgs. 1 cannon cannon fires forward. mgs same pos. as 215. Bomb load over 6000lbs about 2000lbs externally. Engines protrude beyond trailing edge. Fuselage extends beyond tail plane, and acts like umbrella as dive brakes when dive bombing.

[page break]

[underlined] Lockheed Hudson [/underlined]

Coastal command

chiefly recconaisance. [sic]

mid wing twin engined mono. J. F & R’s

[underlined] Engines [/underlined] Radial Air-Cooled

Twin Wasp Cyclone 1200 hp 284mph

[underlined] Arms [/underlined] 7 Mgs.

In nose, pilots cockpit, POGT, dustbin firing aft from belly.

1700lbs. bomb load.

[page break]

[three sketches]

[page break]

Beaufort I & II

Torpedo carrier & recconaisance [sic] mid wing twin engines monoplane & F & R

Engines Radial Air Cooled Torus [sic] & Twin Wasp. 1145hp 265 mph.

[underlined] Armament [/underlined] Usually 5 Mgs.

2 from cockpit 2 in turret 1 under nose firing aft. carries 18” torpedo which weighs 1/2 ton. generally camoflouged [sic] blue on belly.

[page break]

[three sketches]

[page break]

[underlined] BTH Air Compressor System [/underlined]


Used for building up & keeping a pressure in the pneumatic system. Brakes & flaps often operated by air. Browning M/G’s operated by air Compressor driven by engine by standard spline drive. Air comes through non-return inlet valve, is compressed by piston and goes out through release valves Ball bearing non-return valve, outlet valve. 200 - 300lbs per [symbol] “ is normal pressure.


[page break]


[page break]

Petroflex bonding wire comes to a loop & piece of bonding wire is fitted across unions.

Superflexit is internally bonded.

[underlined] Oil Pipe Lines. [/underlined] Avioflexus.

Always covered with wire braiding and has copper bonding strip running through braiding.

[underlined] Hydraulic [/underlined] lines [underlined] Duraflex [/underlined]

[underlined] Rigid Pipes [/underlined] :- Copper, Tungum alloy [inserted] Copper-base [/inserted]

Light Alloy, Stainless Steel

Copper pipes if not to [sic] large a diameter may be bent cold. Light alloy pipes may be bent but need heat treatment after. S.S. [underlined] can’t [/underlined] be bent.

All Metal Coupling


[page break]

[underlined] Rubber Couplings [/underlined]

Red rubber - petrol resisting for fuel or oil.

White - for coolant system.

Rubber has corrosive [inserted] action on [/inserted] metal. [deleted] on [/deleted]

So cover metal. Copper, Tungum. Tinning or Pigment oil varnish.

Pigment oil varnish also used on light alloy & stainless steel.

Brass gauge over rubber to prevent cutting it, by jubilee clip. Rubber coupling bonded by clips & wire.

Nipple Adaptor is used for joining a pipe to a fixed component.

[page break]

3/ [underlined] Eclipse. [/underlined] Electric motor drives fly wheel. Fly wheel driving through gears to clutch, & clutch to dog. Hand turning gear on side. Dog mounted on splines. [deleted] Comes in [/deleted] Switch on electric motor works up speed 3/4 min. Switch of motor, fly-wheel down to 120-1. (3000 approx) mesh by lever control. Solinoid [sic] control. Two types series [underlined] 11 [/underlined] & 41. (Switch off before meshing or will burn motor out by load) on series [underlined] 11 [/underlined] (old type) Series [underlined] 41 [/underlined] newer type heavier motor, permissible to leave motor running while engaging gears. Both types hand starters.

11) Worked by spring loaded control. 1/16” clearance between dogs. Adjust clearance by shims.

[page break]

[underlined] Vickers Cock :- [/underlined]

Can get them with more than 2 connections. With 2 connections, only 2 position [underlined] on [/underlined] or [underlined] of. [/underlined] Stop ring limits handle to 900 turn. Used in systems to isolate parts of system. [underlined] Maintenance [/underlined] Check stop ring for security. No leakage of fuel up spindle tighten gland nut if necessary.

[underlined] Flexible pipes [/underlined] are used to join two components where movement or vibration exists

[underlined] Fuel pipe lines 2 different types. [/underlined]

1/ Petroflex

2/ Superflexit.

Can carry out [underlined] no [/underlined] repairs, fit new pipes, can not alter them. Life of 3 yrs from date of manufacture. Tab date fitted. Superflexit has 1 hexagon & two flats. Petroflex has two hexagons. Copper bonding wire fitted to both under steel winding

[page break]


Always used in con with booster coil (same as hand starter mag. but obtains primary current from battery) Push [deleted] bush [/deleted] button for starter also connects to hand starter mag. so keep button pressed & a stream of sparks is obtained. Test by placing 2 cart in breech. Engine switches to off & fire first cart, then second cartridge.

[underlined] Maintenance:- [/underlined]

See secure & no corrosion wipe over with oily rag. See breech is full of new cartridges.

Change copper safety disc every 25 shots in winter, 40 in summer. Every 75 100 shots lubricate sealing piston with one thimble full of coffman oil. Have half thimble full in each nipple. Every 200 shots remove safety disc holder and put in 2 [deleted] safety [/deleted] thimble

[page break]


fulls of oil. Wait two minutes after firing each cartridge in case a slow burning one.

[written upside down]

2/ Rotax. Consists of electric motor, epicyclic gears 90 - 1. Spring loaded clutch. Bendix quick start thread for meshing purposes. Hand turning gear on side 16 - 1. Spring loaded ratchet in case of backfire, which would also be taken by spring loaded clutch.

Use auxiliary acs. for starting.

3/32 free clearance minimum between dogs. AP1181 Adjust clearance by slotted nut in centre of dog.

[underlined] Maintenance:- [/underlined] Count no. of turns required to bring dog into mesh, to check on wear on leather washer.

[page break]


[underlined] Engine Starters [/underlined]

1/ Coffman Starter (cartridge)

2/ Rotax Starter (Hand & Electric direct)

3/ Eclipse Starter (Hand & Electric Inertia)

1/ [underlined] Coffman [/underlined]

Breech of 5 chambers & 1 cylinder.

Loaded by a loading door.


3200 turn but engines revolve 2 or 3 times. Safety disc fitted, for relieving excess pressure when engine is very cold. Check No. on safety disc when fitting new one to see its same as old one. Fit with formed head out so to get hold with pliers. Sealing piston, seals end of cartridge chamber to tube.

[page break]


draws back while new cartridge is indexed. Two pistons fitted to prevent handle flying back & overide [sic] of cart. chamber.

When fitting new [one indecipherable word] check for correct type, check for size & direction of rotation. Two sizes L & M M for engines up to 1000hp L for engines over 1000hp.

Not less than 1/8” clearance between 2 dogs.


[underlined] B - A [/underlined]

Adjust by shims on flange.

Two holes on cylinder to allow air to be sucked in. Fit with vent holes upwards to prevent oil draining out. If cylinder head doesn’t line up with pipe line slacken clamping ring & rotate cylinder.

[page break]

[underlined] Procedure for timing. [/underlined]

Set cr/s at A6 m.a. Compression stroke Place vellumoid joints in position on mag. drive housing. Select correct mags for A & B side. Fully advance the C.B. and keep at that throughout job. Set the main rotating brush at No 12 segment. (This is the segment nearest BDC on cyl. side in case of both mags. Set the C.B. points just seperating [sic] with the main brush at this position.

Place the coupling on mag. & mark its position for [inserted] furthur [sic] [/inserted] reference. Engage mag with its drive (without allowing the C.B. to move away from its setting) & bolt on engine & repeat with other mag.

Check with lamp & adjust for synchronisation.

[page break]

Inlet Opens 120 before TDC

Inlet Closes 400 after BDC

Ex. Opens 500 before TDC

Ex. Closes 20 after BDC

Kestrel IIs Lubrication System.

Comprises two complete pressure circuits and scavenge. HP. 60lbs [symbol] “ LP. 4 to 10lbs [symbol] “

HP feeds cr/shaft bearing, big-ends, & fuel pump (later types) (earlier types LP). Splash from these lubricate Cyl walls, Pistons & G. Pins.

Low pressure circuit supplies - Prop. Reduction gear (1 pipe & 2 jets. Camshaft & rockers 1 pipe to each block Supercharger driving gear 1 pipe. Impellor [sic] shaft rear bearing 1 pipe.

All oil drains down to sumps from which it is pumped by 2 scavenge pumps (both located in rear sump) Are drawing

[page break]

Insert .03 feeler between tappet & valve stem.

Unlock the tappet lock nut with special tool from kit.

Adjust the tappet screw with the inner part of the same tool.

Lock the lock nut securely.

Re-check the clearance with feeler.

Procedure the same on all cyls.

[underlined] Valve Timing. [/underlined]

Set one inlet valve of A6 and of B1 to .035 clearance.

Turn engine (by prop. shaft) until [deleted] .500 [/deleted] .005 feeler is just nipped between between valve and tappet on B1 cyl.

Disengage B Side drive shaft.

Repeat this procedure on A 6 cyl.

Turn prop. shaft forward (d of r.) until A6 I O is at the pointer. Mesh A side drive shaft. Turn prop. shaft 600 forward till BI I O

[page break]

is at the pointer

Mesh in B side, drive shaft.

The valves are timed now and ready for checking and adjusting if necessary. If timing is early the mark on timing disc will not have got to pointer

To adjust it:- disengage the drive shaft carefully, knock the cr/s forward. Turn the serrated drive shaft one or two serrations, forward as required.

Re-mesh drive & re-check. Finally set tappets to .020 clearance.

Kestral [underlined] (Magneto) Timing [/underlined]

The mags are timed & syncronised A6 MA. 370 TDC. Fully advanced. Note:- The mags are [underlined] not [/underlined] interchangeable.

Contact Breaker Gap = .011 - .013

Both mags. are timed to A6 cyl. Only

[page break]


Nickel steel & case hardened all over except at the extreme front end, and on the taper for the bevel wheel at rear end. Cams arranged in sets of 4. The inlets being inner pair of each set. The 7 al. alloy brackets which house the camp bearings (of which 5 are split al. alloy. 1 all alloy bush at front & 1 Phos. bronze split bearing at rear.) are secured to the cyl. block by [one indecipherable word] 7 steel studs, and located by seven tenons which fit in slots in cyl. [deleted] head [/deleted] block. End thrust is taken by a thrust ball bearing fitted in front of level gear & is [deleted] l [/deleted] adjusted by 2 washers (steel) located one on either side of rear These washers may be varied in thickness to control the end float of shaft & backlash of bevel gears [missing word] rocker & pivot shafts are carried in [missing word] brackets but each rocker

[page break]

shaft is kept from turning by a taper & key on rear bracket.

The rockers of nickel steel are mounted are mounted on Phos. bronze bushes & have hardened pads where the cams press on them. They have a hardened screw locked by a nut in their ends for the purpose of adjusting valve clearance. The end float of Ex. Rocker is adjusted by washers. The inlet rockers positioned by steel clips. A small pinion at the rear of B side camshaft drives the tachometer & a spline extension on A side to drive an auxialiary [sic] such as a gas starter.

Setting valve clearance

Clearance inlet & ex. .030.

Cyl. you are working on at T.D.C. compression. (The cams making the V sign)

[page break]

One tooth of the coupling shaft is marked to obtain correct re-assembly with the reduction gear. Both cr/s pinion & prop red. gear run in roller bearings & each is also fitted with a ball thrust race. At the front end of the coupling shaft there is fitted a timing disc.

Con rods of I Section nickel steel. Floating small and bush of Phos. Bronze. Waisted H tensile steel bolts hold the big end assembly together.

Pistons & Cylinders.

Pistons are of al. alloy (Y alloy) Have 3 comp. rings above gudgeon pin & a scraper ring near bottom. The 3 are butt jointed. The top 2 can slide round no 3 is pegged.

Pistons marked for A & B block on

[page break]

their cyl no & wt. marked there also. When fitting fresh pistons weight must be +/- 1 ounce the old ones. The fully floating hollow steel G. Pins are secured at each end by spring circlips.

The joint between Block & Rocker cover is Velumoid. [sic]

Joint between block & induction system of Klingint.

Joint between block & exhaust pipes of copper & asbestos.

Cyl. Jackets.
Coolant Outlet pipe.
Header Tank.
Radiator back to pump.
By passing some of coolant from coolant outlet pipe to carb, to heat it. From carb it passes directly back to pump

[page break]

Hoist up carefully with crane & lower to bench. Insert Cyl. block on wooden bases.

Attach storage base & secure with 2 nuts at each end.

Bring block right way up & working to sequence strip, screw down evenly all over to storage base.

Removing Pistons:-

No 3 & 4 still at TDC to be taken of [sic] firstly then 2 & 5 then 1 & 6 turning the crankshaft as required. Remove 1 circle and slide out the gudgeon pin towards that end, if unduly tight remove end circlip and drift out the g. pin. Leave

[page break]

g. pin bushes in con rods. Store the pistons correctly laying them on crowns & not on top of each other.

[underlined] Crankshaft [/underlined] :- Nickel Chrome Steel forging. [deleted] No [/deleted] Six throws numbered from the front. Has 7 main journals which run in white metal line plain bearings.

Crankpins six numbered from the front. Located by No 4 bearing. Cr/S is hollow for lightness and to act as a conduit for carrying oil, having holes radially drilled in each journal. The c/s torque is transmitted to the prop through a coupling shaft which is splined into the c/s and also into the bore of the c/s pinion. The latter a spur gear engages with the prop reduction gear, which is a spur gear mounted on the prop shaft.

[page break]

Normally Aspirated type 1B.

1/ Prop hub

2/ Red gear

3/ Ignition cables

4/ Magneto

5/ Carbs & induction manifold

6/ Control standard

7/ Camshaft covers & camshaft

8/ Cyl blocks & pistons

9 Spring Drive unit

Prop hub:- Remove [one indecipherable word] claw, Ring nut locking sleeve & ring nut. Fit thread protecting cap & slide hub off.

Reduction Gear :- Use lifting stirrup & crane.

Priming pipe :- Do [underlined] not [/underlined] remove union nuts. Remove as a unit from Induction Branches. Take care of Atomiser.

[page break]

Ignition cables :- remove as complete units. [underlined] not [/underlined] each lead separately.

Mags :- Don’t leave couplings in engine or control rods on mags.

Removing Camshafts :- Arrange camshaft with two pairs of cams at one end of shaft under load. [inserted] thread rockers with wire or string [/inserted] Remove the eight nuts from the part under load steadily moving from one to the other a thread at a time. Lift camshaft clear of cyls & place on a proper board. Removing cyl blocks, [inserted] No 3 & 4 pistons at TDC [/iRemove all nserted] remove all pipe connections. Undo the gland nuts of drive shaft covers. Remove all spark plugs or dummies.

Remove all holding down nuts & dogs. (use the sequence strip for this job) Attach the lifting eye securely in the middle of block. (Nos 3 & 4 studs

[page break]

the reduction gear case; & to the rear end [deleted] of [/deleted] the wheel case. Behind the wheel case is the supercharger. With the II S Kestrel the supercharger gear ratio is 10 - 1. Cubic capacity of engine 21.3 litres. 2 mags fitted. The A side fires all the inlet plugs B side fires all the exhaust plugs. The Oil pressure pump is bolted on below the rear pump.

Plain, White Metal lined bearings are fitted to main & crank - pin [deleted] bearings [/deleted] journals. Lubrication on the dry sump principle. 1 Pressure pump & 2 scavenge pump being used. Pressure :- High 50 - 70 lbs per [symbol]”. Minimum permissible 30 lbs [symbol]”. Low pressure circuit 4 - 10 lbs [symbol]”. DTD 108. Temperatures

[page break]

250 degrees cent. Inlet min before flight

800 degrees cent. inlet max before flight

Outlet max 1050

Oil Consumption 3 - 4 pints per flying hour.

[underlined] Dismantling Sequence. [/underlined] Supercharge

1/ Prop hub

2/ Reduction Gear

3/ Supercharger unit.
9/ B side
4/ Spring drive unit & compound wheels.

5/ Coolant outlet pipes

6/ Priming & redistribution pipes.

7/ A side ignition cables

8/ Induction manifolds & trunk.

9/ B side ignition cables

10/ Magnetos (including their coupling shafts

11/ Camshaft covers & camshafts

12/ Cyl. Blocks & Pistons

[page break]

[underlined] II S Kestrel. [/underlined]

12 Cyl. Liquid cooled V type.

600 between cylinders. 5” Bore stroke 5 1/2” Compression ratio 6 - 1.

Dor R Camshaft Left Hand

Propellor Right Hand

Camshaft (2) Right Hand

Mags. Both toward front of engine.

A Left hand B right hand

Reduction gear to prop single spur gear type. .553 to 1

[table of number]

Firing order 1A, 6B, 4A, 3B, 2A, 5B, 6A, 1B, 3A, 4B, 5A, 2B.

[page break]

Nominal H.P. 500.

Overhead camshafts are fitted, the drive being taken from wheel - case by inclined drive shafts. The 6 throw crankshaft is carried in 7 main bearings. The crankshaft are paired 1 & 6, 2 & 5, 3 & 4, at 1200 spacing. Connecting rods are of the forked and plain types, so that each crankpin has two pistons connected to it. Pistons of al. alloy are secured to small end of con - rods by fully floating steel gudgeon pins working in Phos. Bronze bushes.

The crankcase of al. alloy is in two portions. The upper carries the cyl. blocks & crankshaft. The lower portion carries the scavenge filter & pumps (2) There is a sump at each end of the lower portion. Bolted to the front end of the crankcase is

[page break]

How are valve seats & spark plug adapters fitted & held in cylinders?

Rear cover mag. alloy lightest metal, very inflammable. Rubber ring between it and volute casing = oil tight joint.

An Hercules rear cover is called auxilary [sic] gear box.

Check valve opens at 5 lbs and shuts when engine is not running and keep oil from flooding cylinders. From check valve to pressure chamber to tailshaft bearing teeth of oil pump iron, nickel, aluminium bronze. From inner anulus to lubricate mag. Spring.

[page break]

Priming the engine with oil. After installing new engine or if an engine has been standing more than 5 days, it must be primed with oil before running. The oil is at a temp. approx 600 C and is forced through the pressure guage [sic] connection by an hand operated pump while the engine is turning. The pump pressure must not exceed 60lb & quantity not less than 1/2 gal. To pump fulls are injected into nipples on rear cover & 4 pump fulls on nipple of crankcase to hub blower gears.

[page break]

Type of Reduction gear & its reduction? How is the gear lubricated? How can reduction be altered? What is purpose of thrust race? How is reduction gear driven? What are gears made of? How do the levels centralise themselves?

How would you time the magneto? Why is primary circuit insulated and how? If port magneto was U.S. would it be necessary to remove starboard magneto? How would you synchronise both magnetos?

[page break]

What is valve clearance and how is it set? Why check on four dwells? Describe engine layout?

What is crankshaft made of? and describe it? How is rear portion attached to front portion? How is crankshaft supported? Describe master and articulating rods? Why are wrist pins offset? How are wrist pins lubricated?

Describe piston and difference between it & others?

How is cylinder head fitted to barrel?

Difference between exhaust & inlet valves? How would you know if NCM valve seats fitted?

[page break]

Farman Epiyclic [sic] Bevel Reduction Gear. All wheels of nickel chrome steel.

At the rear phosphor bronze ring, at the front magnesium ring.

The front thrust bearing is fitted to transfer thrust from the airscrew shaft to the reduction gear casing & then to the engine, finally to the aircraft.

[page break]


[page break]

7/ Reverse engine a few degrees & then tap forward until the lamp goes out (this should be at 350 BTDC.

8/ Correct any error by adjusting on coupling 1 serration = 2.10 c/shaft movement.

Permissible error + or - 10

9/ Repeat procedure for other mag. and synchronise.

10/ Finally remove clip, oil silk, & locks adjuster nuts.

opposite D of R.

Take back more than 350 then bring up to 350 to avoid backlash.

When finished take oil silk out, remove clip, and put split pins on nuts on serrated wheels.

[page break]

[underlined] Crankshaft [/underlined]

In 3 parts 1/ Front half

2/ Rear half

3/ Tailshaft

Material:- Nickel Chrome steel drop forged. The rear web is split and fitted to crankpin and held by a maniton bolt.

[underlined] Con Rod Assembly [/underlined]

Consists of one master rod and 8 articulating rods.

Material: High tensile steel - drop forged. ‘H’ Section. Articulating rods are held to master assembly by wrist pins. Big end houses a freely drilled, fully floating white metal bush. Gudgeon pin bushes - gun metal & shrunk & dowled [sic] into rod.

[page break]

[underlined] Angle of Attach [/underlined]

Is the [symbol] between the rocker arm and the valve stem. The ideal [symbol] of attach giving minimum wear is 900 when the valve is 1/3 open. To check [symbol] :- [underlined] No1 [/underlined] [inserted] cyl at TDC compress [/inserted] Tighten down rocker on taking up tappet clearance, [deleted] therefore taking [/deleted] loosen of [sic] one of rocker arms. Place depth gauge in position and check gap between gauge & mushroom, if gap is between .060 & 0.020 the clearance is correct. If clearance is over .020 push rod too small. Remove same and check for bow. Bow may be remedied by tapping with hide faced hammer. If rod is too small fit new one will be .060 oversize, check clearance and to bring within the limit remove end piece and file.

[page break]

Setting Tappet clearances

1/ Put Cyl at TDC compression

2/ Set clearance to .060 [inserted] exhaust [/inserted] using two sets of feeler guages. [sic]

3/ Set clearance on highest dwell and set all cyls using highest dwell.

4 After setting No 1 cyl move crankshaft 3200 D of R. to bring dwell on to No 9 cyl set clearance & carry on for all cyls.

Same procedure on inlet tappets.

[underlined] Magneto Timing [/underlined]

1/ Using P.P.I find TDC compression No6 cyl.

2/ Set engine to 350 before TDC.

3/ Insulate mag. primary circuit with oiled silk, and check CB.

4/ Clip automatic advance & retard in the fully advanced position.

5/ Rotor opposite No 6 segment points just opening.

6/ Offer mag. To engine & attach lamp & battery.

[page break]

Fitting Reduction Gear.

1/ Lubricate with 1/2 pint oil

2/ Have master spline facing upwards

3/ Offer up reduction gear

4/ Tighten up in opposite

5/ Run round joints with .002 guage [sic]

Cylinder Changing

Always remove no 6 cyl. last & remove cyls. as opposites.

No 1 cyl. to be on TDC compression undo base nuts of stack pipes & slide joint & rubber free undo locknut on top of stack pipe & slide pipe clear of crankcase.

Remove nuts at base of push rods and also remove gas starter pipe

[page break]

Remove nuts securing cyl. & pull cylinder clear of c/case.

[underlined] Fitting Cyl. [/underlined]

Reverse procedure.

Lubricate rubber ring in warm oil. Lubricate cyl walls.

No on cyl at front.

Check [symbol] of attach & tappet clearance. Remove at least one sparking plug.

[underlined] Fitting Piston Ring [/underlined]

Demand correct type. Check free gap, check working gap using piston & cyl. Check ring for thickness. Check in fits & clearances volume. Fit ring using 3 pieces if tin.

[page break]

2 Plugs in phosphor bronze adaptors, also shrunk in and dowled [sic] into head.

[symbol] Valves.

Valve seats of Nickel Crome [sic] Manganese. Hard wearing stands heat. Anlge [sic] of valve seats 900 hole drilled in top pin show NCM. 2 holes when reconditioned.

Gas starter valve also in p.b. adapter now obsolete.

[deleted] Outside inlet valve inside [/deleted]

Rocker box held in 3 places by 2 trunnions and a tie rod.

[underlined] Valves [/underlined]

Made of KE965 stems being nitrogen hardened and tube shaped heads. Detachable steel ends are fitted on the stem. [symbol] of valve is 900. Exhaust valve is 910, hollow stem half filled with sodium salts which transfer heat from head to stem.

[page break]

[underlined] Valve Springs [/underlined]

Vanadium steel & are in threes wound in opposite direction to prevent fouling if break.

[underlined] Removing Reduction Gear [/underlined]

1/ Remove airscrew hud [sic] & place drip tray underneath. Turns airscrew shaft until master spline is facing top of casing [deleted] reduction gear [/deleted] & mark with chalk in one or more places. Undo nuts round casing except 4 unscrew these to end of thread. Fit thread protection over airscrew shaft thread. Tap shaft with hide faced hammer in several directions & fit five wedges of wood between two faces. Carefully remove reduction gear.

[page break]


[page break]

[underlined] Cylinders [/underlined]

Interchangeable, if new but can’t change 3 to 4. Set 400 between Steel barrel. Alluminium [sic] alloy head

To attach head to barrel.

Head heated to 3200 and screw to cold barrel. Cools down and fits tight to cold barrel. Cools down and fits tight, head also made .0020” smaller than head. Steel ring heated and shrunk to joint. When engine gets hot alloy head tend to expand but ring keeps it tight. Copper washer between head & barrel forms gas tight joint Regard as integral. Barrel heavily finned. Flange at bottom with 8 holes bolts to c/case. Rubber washer between flange and c/case. Spigot slides into c/case. Scallops in spigot clearances for conn. rods.


[page break]


[underlined] Cam Sleeve Operation [/underlined] [deleted] Cylinder [/deleted]

Nickel chrome steel.

Crankshaft sleeve master splined to crankshaft and drives cam sleeve. Cam sleeve revolves opposite to crankshaft & at 1/8 engine speed. Oil at 60lbs [symbol] “ pressure is fed along 3 flats on crankshaft to a groove in crankshaft.

[page break]

[underlined] Pegasus 2M3. [/underlined]

9 cylinder air-cooled radial engine. Stroke 7 1/2”. Bore 5 3/4” Swept volume 1753cu” volume of cylinder from TDC - BBC. Compression Ratio 5.5 - 1. Reduction Gear Ratio .5 to 1

135792468 Firing Order

DTD 224 Petrol

DTD 109 Oil.

[underlined] Valve Timing [/underlined]

Inlet Valves Open 120 before TDC

Inlet Valves Closes 500 after BDC

Exhaust Valves Open 650 before BDC

Exhaust Valves Close 310 after TDC.

Valve Clearances

Inlet .004”

Exhaust .006”

[page break]

[underlined] Continuity [/underlined]


lamp & battery

to see if current is flowing in one end & out other end

[underlined] Insulation [/underlined]

To see if current isn’t escaping through metal lead cover.

[page break]

VOL I A.P. Concerned. General Description

VOL II Part I General Orders & modifications.

Parts II Fits, Clearances, Repairs Tolerances.

Part II Airframes, Maintenance.

VOL III Spare Parts. contains checking list

[deleted] Dismantling [/deleted]

[page break]

[underlined] Cam Lubricating Pad [/underlined]

1 Drop engine oil W. 9 every 60 F. hrs

If new type take clip of & pad out & renew every 60 F. hrs. i.e. if impregnated pad.

[underlined] Advance & Retard. [/underlined]

A suitable grease lightly smeared onto spigot. Check for no wobble.

[deleted] Distributor [/deleted]

Adjust Contact Breaker Points to .012 +/- .001

[underlined] Distributor. [/underlined] 120 F. Hrs.

Wash in lead - free then water 750 C +/- 50 C. then Rinse, Look for cracks. If cracked whole magneto withdrawn. If segments are pitted use emery & oil. Also same for brush on rotor & check gap between brush & segments by GO-NO-GO Gauge.

Check brush gap for wear by dummy distributor .011 - .019

[page break]

6 drops of Engine oil every 60 hrs. in three lubricating wells

[deleted] For [/deleted]

For lubricating refer to Unit Maintenance orders.

For starting use hand starter mag. time current by trailing brush on main magneto.

[underlined] Leads [/underlined]

H.T. 40 Strands T. Copper Wire

19 Strands Stainless Steel

L.T. 23 Strands T. Copper.

Don’t bend leads more than 4 1/2 R. or waterproof cover rips.


[page break]

Safety Spark Gap no good at altitude so fit heavier coil to stand up to heat generated. S.S.G. not fitted now except to rotating armature mag. which can’t have bigger coil. Less pressure can pump S.S.G. easily at ht, goes straight to S.S.G. least line of resistance.

Arcing:- particles of white hot material, carried across.

[underlined] Maintenance. [/underlined]

[underlined] Contact Breaker [/underlined] platinum alloy [inserted] won’t in oil [/inserted]

[deleted] Clean [/deleted] Wash in lead free petrol, wipe and dry.

Can get pitting on surface by ageing.

[underlined] Slipstone smeared in oil to level faces off. [/underlined] If very bad file first in case hardened steel plate [sketch] then finish of with slipstone & oil.

[page break]

[underlined] Contact Breaker [/underlined] Points of Tungsten.

Will work in oil. Stand up to heat. Tungsten very hard & can have convex surfaces, then won’t trap oil.

Fine emery cloth and oil, if slightly pitted.

If badly pitted draw new points from stores.

[underlined] Rocker Arm. [/underlined]

Phosphor bronze bush mounted on [one indecipherable word] check for wobbling. Oil every 60 F hrs in with 1 drop of winter grade engine

Check [underlined] fibre heel [/underlined] for wear

[underlined] Contact Breaker Spring [/underlined]

Examine for security, cracking, discolouration. Check for signs of blueing, due to heat. Check for signs of varnish on spring, flaking. If so clean of [sic] old varnish with dope solvent, revarnish except 2 ends.

Check tension 2 lbs +/- 1/4 lb. using tension gauge & L just behind contact breaker points

[page break]

Distributor [one indecipherable word] (metal) over distributor.

Most engines started by hand starter mag.

Two leads to mag. one from hand S. mag. one for cockpit switch.

[one indecipherable word] (pure oxygen)

Nitric acid, corrode, so ventilating holes to clear air.


[underlined] Broken switch wire means a live magneto. [/underlined]

[page break]


[page break]

2 [underlined] Armature core :- [/underlined] Primary Coil, Secondary Coil Outside I.S.

Polar inductor magnet stationary .

R.M. Magnet rotates insides fingers on inductor shaft.


Lines of force go one way then reverse.

[underlined] If magnetism is reversed through armature coil a current of electricity is obtained. [/underlined]

[underlined] Lines of force :- [/underlined]

collectively called [underlined] Magnetic Flux. [/underlined]

Magnetic Field.

4 Flux reversals. (P.I or RM)

If current is flowing through primary coil and switch it off with contact breaker, we get a current in secondary circuit [deleted] sent [/deleted] and is sent to plugs.

[page break]

[underlined] Contact Breaker:- [/underlined]

Consists of little arm of duralumin revolving up to 300 per secs.

[underlined] Condenser:- [/underlined] is used to reduce arcing and sparking at the contact points.


Sheets of tin foil separated by sheets of mica. Assists contact breaker to give quick reverse and switch off.

[underlined] Distributor:- [/underlined] Distributor Rotor

Distributor Block

[underlined] Earthing Switch:- [/underlined] In the cockpit.

[underlined] B.T.H. Type SC9 - 4B. [/underlined]

Bristol Pegasus P.I. mag. 4 sparks per revolution. D.oR. taken by looking at the front, applies to any magneto. Always rotate in to engine. 3 ways of mounting. [underlined] Spigot Face, [/underlined] Flange. Base Mounting,

[page break]

[underlined] Nolley [/underlined]


[underlined] Stromberg [/underlined]


Under no conditions must mixture control lever be be moved from Idle cut off position when engine is stationary.

[page break]

[underlined] Magnetos. [/underlined]

Three basic types.

1/ [underlined] Rotating armature [/underlined] (RA) 2 sparks/per rev up to 6 cylinders. Have to drive mag. to [sic] fast, over 6 cylinders. Is a hand starter magneto & test equipment.

2/ [underlined] polar Inductor [/underlined] (P.I.) At least 4 sparks per rev, engines of 7 cylinders & over.

3/ [underlined] Rotating Magnet [/underlined] no difference as far as maintenance is concerned, to No1.

In all mags there are [underlined] Permanent Magnets:- [/underlined] This enables us to obtain electricity


[page break]

[underlined] Automatic Boost Control. [/underlined] (ABC)


When diving at full [deleted] through [/deleted] throttle super c. develops to as air gets denser. A.B.C. closes throttle.

[underlined] Boost Control. [/underlined]

The progressive cam is fitted to give a definite boost pressure for a given throttle opening up to rated altitude.

Cross Shaft, Relay Piston [inserted] 3.5ccs Anti-freeze oil as much as you can get in C.S.

Cross Shaft Relay Valve.

Oil used:- Anti-freezing oil.

also oil link-work. carry out on every 30 [inserted] flying [/inserted] hr. Inspection.

[page break]

To lubricate R.V. remove atmospheric union close throttle and shoot in 3.5 ccs. of anti-freeze oil.

Wobble pump in American kites works up pressure of petrol from carburettor. Red light warns when pressure required is reached. When engine starts engine pump takes over.

KIGASS Priming Pump. No of strokes depends on engine

Start up Merlin.

Prime as required. Pump up pressure required on wobble pump 2 - 3 lbs & then start.

[page break]

If you increase pressure of gas it becomes hotter.


To avoid detonation, as pressure increases make the mixture richer.

[underlined] Boost Enrichment:- [/underlined] petrol cools engine: & absorbs heat.

Another aneroid operated by boost [deleted] pipe [/deleted] pressure, by pipe from induction manifold. As pressure increases mixture becomes richer.

[underlined] Safety valve [/underlined] in case blow back from engine smashes aneroid.


Valves closed by sudden pressure this protects aneroid.

Valute drain on super. C to drain away condensed petrol. assists slow running.

[page break]

Stop engine by allowing atmospheric pressure to enter slow running chamber, through [underlined] Slow Running Cutoout [sic] [/underlined] [symbol] no difference in pressure [symbol] no petrol drawn through. Engine stops.

Choke tubes heated by hot coolant. Butterflies heated by hot oil from scavenger pump. Heated to stop freezing.

Two brass taps to get rid of air locks when filling up with coolant.

All oil from scavenger pump goes through butterflies.

Oil relief valve at 25 lbs. When oil is cold & [one indecipherable word] [symbol] high pressure it goes out through outlet via relief valve and doesn’t go near butterflies

[page break]


When large hole is uncovered by butterfly, switches over to main jet again.

When butterflies are opened petrol doesn’t respond immediately and engine splutters & lags known as Flat Spot.

Flat Spot overcome by accelerator pump.


Neat petrol forced out into cylinder near venturi through 5 holes in cylinder wall.

[page break]

The pressure which the supercharger builds up in induction manifold is called Boost Pressure.

Measured in lbs per [symbol] “ (Br) inches Hg (Am). HG. Mercury. S.C. has limit of height at which it can maintain sea-level power.

[underlined] Rated Boost Pressure:- [/underlined] Maximum pressure which manuf. [deleted] allow [/deleted] for running over indefinite period.

[underlined] Rated Altitude:- [/underlined] is the greatest height at which we can maintain rated boost.

The maximum boost press. permitted by the manuf. for a period of not more than 5 mins, is

[underlined] Maximum Permissible Boost, [/underlined] used for take off, initial [inserted] climb [/inserted] & emergency.

[underlined] Detonation:- [/underlined] explosion in cylinder of weak mixture

[page break]

Diffuser is used to give correct mixture at all engine speeds except slow running.


As you climb wt. of air & pressure drops. Air expands at height. To [sic] rich a mixture as you climb. Cut down petrol supply.

[underlined] Altitude Mixture Control [/underlined]

Gives correct mixture at all altitudes. [underlined] (Aneroid). [/underlined] Aneroid expands at height & pushes needle into jet thus cutting down petrol as air gets less in weight.

Loss of pressure, consequently power at height.


[page break]

[underlined] Supercharger [/underlined] to maintain sea-level power at altitude. Pump mixture up to sea-level pressure. Maintain sea level power up to certain altitudes. Driven at 6 - 10 times crankshaft speed revolve up to 30,000 R.P.M.

[underlined] Slow running jet:- [/underlined]


No rush of air through choke tube at slow running, [symbol] not enough drop in pressure to draw petrol.


[page break]

adjust & clean contact breaker points with an oilstone. Put one drop of oil on contact b. p. One drop of oil on cam ring, down hole to felt pads and smear with high melting point. Wash carbon brushes with petrol & glass paper [underlined] not [/underlined] emery cloth.

[page break]

[underlined] Carburettors. [/underlined]

gives us a correct ratio of air & petrol & ejects it into cylinder. (11-15). to / [underlined] by weight. [/underlined]

At. Pressure at sea level = 14.7165 lbs [symbol] “

Pressure difference between two sides important.

Increase the speed of a gas, decrease the pressure.

[2 sketches]

No use:- only good at one choke opening. To [sic] rich a mixture

[page break]

Remove insulation from primary circuit

[2 sketches]

Float:- Thin brass coil, light & frail.


[page break]

Venturi :- increase of speed without decreasing volume.


Lower pipe almost on [one indecipherable word] jet, and a supply of air & petrol is sucked up

Faster engine goes, the petrol level drops & only air is sucked up thus it acts as extra compensating jet.

Air Bleed

Pressure Balance.

[page break]


A contact breaker is a mechanical switch placed in a primary circuit to interrupt the flow of current.


Condenser made from sheets of tin foil & mica.

It prevents burning of contact breaker points & assists in reversal of primary current.

Low tension currents flowing through circuit.

Primary circuit is few turns of heavy wire.

Secondary circuit many turns of light wire.

[page break]

Safety Spark Gap a safety device to prevent burning of secondary circuit if a plug lead falls of. [sic]

Mag Timing

1/ Turn the engine in D.O.R. to the required number of degrees before TDC compression stroke (marked MA on tractor plate)

2/ Adjust contact breaker points to 12 1/2 thou, & insulate primary circuit.

3/ Fully advance magneto & turn mag DOR until contact breaker points are just opening with distributor rotor serving No1 segment.

4. Engage mag. with Sims vernier coupling.

5. Test timing with lamp & battery

[page break]

[underlined] Timing. [/underlined]

1/ Turn crankshaft in direction of rotation to 200 before T.D.C.

2/ Set clearance of No1. inlet valve to .005”.

3/ Turn Camshaft in direction of rotation until clearance is taken up.

4/ Mesh driving gears in this position.

5/ Check by turning engine in direction of rotation & noting position in degrees point when inlet valve just begins to open.

6/ Tighten & lock the driving wheel retaining devices.

7/ Set tappets to correct clearance.

[page break]

[underlined] Types of Gears. [/underlined]

Spur Gear :- [sketch]

Spiral Gear :- [sketch]

Worm Gear :- [sketch] like a screw.

Helical Gear :- [sketch]

[underlined] Valve lead [/underlined] is the no of degrees measured on the crankshaft by which a valve before its theoretical

[underlined] Flame rate, [/underlined] time taken for mixture to burn

[underlined] Dual ignition [/underlined] gives quicker flame - rate.

[sketch] Magnetos, is a dynamo S to N.

rotate coil of wire in magnet and electricity generated

armature :- coil of wire round soft iron core.

Laminated sheets stuck together

[page break]

Self lubricating from oil it pumps. Disadvantages of wet - sump:- oil in engine never gets cooled properly, doesn’t retain its viscosity therefore.

[underlined] Dry Sump. [/underlined]


Scavenging pump larger mesh than press. pump to make sure pump is kept low.

[page break]

[underlined] Piston Rings [/underlined]

[sketch] Scarf Type

[sketch] But Type

[sketch] Step Type

[sketch] Peg Type

[underlined] The Four Strokes [/underlined]

Induction, piston goes down, sucks in.

Compression, piston goes up, compresses gas.

Power, piston driven down.

Exhaust, piston goes up, forces gas through outlet



Brass nuts on exhaust.

[page break]


Drysump. Merlin



most aero engines.

[underlined] Wetsump [/underlined]

Some parts lubricated by splash others by pressure.

Pressure needs oil pump.


bolted to crankcase. Needs oil tight. No packing on Gypsy. Metal to metal joints. Keep joints clean and smooth with fitters blue. rub on surface table scrape of [sic] high spots.

[page break]

Aerobatic screen, prevents oil flooding cylinders when plane is upside down.


safety valve to relieve pressure, opens at max oil press. 45 lbs

excessive pressure forces spring up and oil escapes to sump

by pass valve in filter for when filter clogs up. pressure of oil opens by pass. The dirty oil is carried round, but better than none at all.


Inlet is larger bore than outlet, so can tell by just looking at it.

[page break]


[page break]


[page break]


[page break]


[page break]

Spencer. J. Capper


S’qud LRd.


[page break]

[rear cover]


“Notebook,” IBCC Digital Archive, accessed October 6, 2022,

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