Harrold Wakefield flight engineer notebook

Harrold Wakefield flight engineer notebook

Covers: fuel system, oil system, Dowty hydraulic system (undercarriage, radiator shutters, flap circuit), electrical system (u.c system, detonator circuit, starter and feathering circuit, bomb jettison and main electrical panel switches and lights). Snag chart with faults and corrections. Continues with oxygen system, portable fire extinguishers and fire drill. Engine handling tables (boost and supercharging explanation), aircraft performance (range and duration flying), flight data and aircraft and engine handling notes.

Multi-page notebook with handwritten entries

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MWakefieldHE174040-171016-18

H.E. WAKEFIELD [underlined] D. W. [/underlined]
85 Evington
[underlined] Leicester [/underlined]

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[Calculations]

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[underlined] FUEL SYSTEM [/underlined]

Manufacturers course
Liverpool 3/7/43 – 10/7/43

[deleted] Fuel used divided by air miles = miles per gal. [/deleted]

[Diagrams and calculations]

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[underlined] OIL SYSTEM [/underlined]

[Diagrams and calculations]

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A two way cock is fitted to the oil tank sumps, when the cock is forward the tank is connected to the engine. A short length of tube is welded to the sump cock lever which prevents the replacement of the cowlings unless the cock lever is set in the forward position. In the case of the inboard engines this cock is mechanically inter-connected to a cock in the overflow pipe, & when the sump cock is in the forward position the overflow pipe is closed. When the sump cock lever is in the aft position the overflow pipe is open, making it impossible to overfill the tank.

Accessibility to the filler cap of inb. tank is on the upper surface of the m/p between inboard engine & fuselage (centre plane)

Sump cock inb. board is on lower surface of m/p between engine & fuselage.

Filler & sump cock of outboard tank are both in same place in bottom rear cowling of outer engine nacelle.

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Vent pipe line drain cock is fitted on rt. hand side [deleted] of the [indecipherable words] [/deleted] of rear face of inner engine bulkhead.

[underlined] Oil Dilution: [/underlined]

At 1000/1200 revs. with oil temp 45°C & coolant temp. at 60°C. Air temp. below -10 press for 2 mins. above -10, 1 min. Valve fitted on left hand side of each engine [deleted word] on bearers.

[underlined] DOWTY SYSTEM [/underlined]
[underlined] Reservoir. [/underlined] – Port side of fuselage above front spar 3 3/4 DTD44.
5 3/4 gals. required to fill pipe-lines etc. Total 9 1/2 gals.
[underlined] Hand Pump [/underlined] – Attached to front spar starbd. side. Incorporating N.R.V. & relief valve. 2500 lbs. [symbol]”.
[underlined] Lockheed Acc. [/underlined] – Under port rest seat rear of front spar.
[underlined] Pressure Filter. [/underlined] – Rear of front spar slightly to port. Should the filter be chocked a ball valve is lifted off its seat & allows the oil to pass through the filter unfiltered.
[underlined] Ex. Supply Return Valve [/underlined] – Starbd. of each inner engine bulkhead in pairs. Supply valve on top & return valve below.

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[underlined] DOWTY HYDRAULIC SYSTEM [/underlined]

[Diagram]

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[underlined] Vokes Filters [/underlined] – Situated in inboard engine nacelles.
[underlined] Lockheed Cutout [/underlined] – Rear of front spar immediately above pressure filter
[underlined] P.R.V.’s [/underlined] 7 in system fitted in fuselage bomb-bay forward of front spar 4 on starbd. & 3 on port side, 2800 lbs.

[underlined] DOWTY U/C CIRCUIT [/underlined]

[Diagram]

[underlined] [deleted] To [/deleted] Select U/C Down [/underlined] – withdraw mechanical up locks – select u/c down – if no indication for u/c locked down – use hand pump. If still no indication for u/c locked down, select neutral, open u/c emergency air vent, select down. Solenoid switch on

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forward side of outer leg of u/c.
[underlined] U/C Emergency Air Vents [/underlined] – Rear of front spar slightly to port a key is provided to open air vent.
[underlined] Rotary Control Valve [/underlined] behind pilots bulkhead.

[underlined] RAD. SHUTTERS & LANDING LAMP [/underlined]

[Diagram]

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[underlined] FLAP CIRCUIT [/underlined]

[Diagram]

To lower – select flaps down. If flaps don’t come down use hand pump. If they still don’t come down pull down emergency flap & open air control valve. When flaps are down release air control valve lever.
[underlined] Air Emergency Valve [/underlined] – in fuselage bomb bay to rear of centre bomb door jack slightly to starbd.
[underlined] Air Control Valve [/underlined] – front face front spar behind emer. flap.
[underlined] Wing Flap Restrictor [/underlined] – Starb. side F.U. bomb bay rear of rear spar

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[underlined] Emergency Air Bottle [/underlined] consists of two cylinders which are screwed & silver soldered into either side of a diaphragm. Thus forming two separate air bottles. One for flaps & one for bomb doors.

Each bottle is fitted with a 2000 lb. gage [sic] & its own inflation valve. Both sides are inflated to 1200 lbs. Fitted under port side rest seat forward of rear spar. Fitted for 1/ Safety, 2/ to enable flaps to blow up at some predetermined air load (I.A.S. 160)
3/ To prevent excessively high pressure building up in a closed circuit due to temp. rise.

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[underlined] BOMB DOOR CIRCUIT [/underlined]

[Diagram]

[underlined] Bomb Door Stop Cock [/underlined] Starb. side frame 7.

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[underlined] ELECTRICAL SYSTEM [/underlined]

Red light on all the time gen. packed in
Red light coming on when a load is put on (accs) (e.g. using turrets) & going off when load is taken away then main fuse has gone or cut-out stuck open. Change fuse, if no result close points of cut-out with fingers.

[Diagram]

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[underlined] U/C System [/underlined]

[Diagram]

If one wheel is locked down the green light & the red light show, & just the red light shows for the wheel which isn’t locked down.
So if only one green light shows then the other bulb has gone.
Airborne throttle closed fuse gone red light bright, green light very dim. Open throttle again & red light should go out. If so then it is O.K. to land.

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[Table]

[underlined] Detonator Circuit [/underlined]

[Diagram]

2 Push Buttons in series } entirely separate
Master Switch & Crash switch in series } entirely separate

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[underlined] STARTER & FEATHERING CIRCUIT [/underlined]

[Diagram]

[underlined] BOMB JETTISONING [/underlined]
If button is used first incendiaries & containers go.
If button is used last empty containers go.
To release bomb racks turn butterfly [inserted] to close [/inserted], hold down locking arm & pull back bar.
To release bombs manually press bell crank lever & they will drop safe if fuse switches are off. If fuse switches are on & serviceable, bombs will explode.

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[underlined] Main Electrical Panel [/underlined] – Rt. hand side of W/O on which are 3 electrical cut-outs, 3 main charging fuses, 3 charge fail lights, 1 ammeter 1 voltmeter, 2 landing lamp relays, fuses 1-44 & 53, 54, 55.
[underlined] 3 Voltage regulators [/underlined] are behind W/O’s back.
[underlined] F Panel [/underlined] Starboard side behind rear [deleted] panel [/deleted] spar on which are fuses 45, 46, 47.
[underlined] Junction Box D [/underlined] starb. side opposite navigators table, 4 bomb gear fuses including bomb door warning lights fuse, main, front & tail fuses.
[underlined] Bomb door warning lights [/underlined] on co-pilots & b/a panel.
[underlined] Heating Suit Switch [/underlined] starb. B/A panel
[underlined] All fuses for turrets [/underlined] inside turrets.
[underlined] D.R. Compass Switches [/underlined] above navigators table.
[underlined] D.R. Compass [/underlined] rear of entrance port side.
Switches at ON & SETTING when moving A/C on ground & on take-off. When airborne switch to normal.

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[underlined] BLO[indecipherable letter]E-TUBE CONTROL.[/underlined]

[underlined] Snag Chart [/underlined]
[underlined] Fault No. 1 [/underlined] Ball pips fouling end of joint slot. This causes spring in end of main control lever travel & [deleted letter] can because of breaking lever ball.
[underlined] Cause [/underlined] incorrect adjustment.
[underlined] Correction No. 1 [/underlined] Set control lever opposite mid-point nick on edge of quadrant [deleted letter] on throttle box, check position of pips on all ball crank levers, & if not central adjust tube length until levers are at rt. [symbol] to tubes. Pips will then be centrally placed in slots. Finally, adjust component levers to mid-point of travel. [underlined] Always regard mid-point of travel as the only positive datum line from which to make adjustments. [/deleted]
[underlined] Fault No 2 [/underlined] Any system, u.c. throttle, C.S.U. blower etc not giving full travel.
[underlined] Cause [/underlined] – Pip or pips fouling or adjustable balls on levers nearest engine overlooked.
Either [deleted letter] can introduce spring at either end of

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travel on throttle box.
[underlined] Correction No 2 [/underlined] As no 1 above.
Adjust balls on lever assemblies nearest engine. In to increase out to decrease travel on opposite arm of lever & tube. When adjustable arm is nearest engine above adjustment has reversed effect. Note that adjustment of tubes does not affect travel, adjustment of tubes only varies relative positions of levers.
(A & B) If control has spring at either end make sure of nature of spring. Disconnect joint nearest component, then move control lever through full travel. If free from stop to stop quadrant system is free of fouling pips & travel on component maybe excessive. In such a case reduce travel by adjusting on lever ball. (1/8” of spring either end is sufficient.)
If spring remains when disconnected a pip or pips are fouling restricting travel therefore, centralise as no 1 above.

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[underlined] Fault No 3 [/underlined] Lost motion in any system.
[underlined] Cause [/underlined] Backlash
(A) This may be result of wear in joints or balls.
(B) Joint keys not turned to locked position, or spring clip replaced in wrong position.
(C) End float or slot in lever bushes

[underlined] Correction No 3 [/underlined]
(A) Renew worn joints where necessary. Any joint [deleted letter] that is spring loaded when locked is not an efficient joint.
(B) Ensure that nick on top of joint key points towards ball, & that spring clip is pushed over case of joint
(C) Any end-float or wear in lever bushes should be taken up or replaced, especially on throttle [indecipherable word] motion levers, in nacelle or about bulkhead.

[underlined] General [/underlined] Always proceed with adjustment from control box towards engine. Ensure that joints are clean & free dirt or grit initially. Lubricate well with anti-freezing grease DT[indecipherable letter] 143 (or current specification)

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When assembling bell crank lever assemblies ensure levers are as free when rigged in position as before. When adjusting friction break ensure lever has about 1/8” of slack in unlocked position this will avoid unnecessary friction being applied on control levers. When locking up nut on adjustable end joint avoid using ball in either joint as a tommy bar. Undue pressure is unnecessary as tubes cannot work loose. A 1/8” diameter hole is now provided in joint cases. A ‘C’ spanner or 1/8” diameter rod can be used to hold joint & relie[deleted letter] [inserted]v[/inserted]e ball of this strain. The above neglect is generally cause of fractured balls on levers.

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[underlined] OXYGEN SYSTEM [/underlined]

11 Economisers.
10 Cut-Off Valves (first pilot without).
10 Flowmeters (co-pilot without).
54 Non-return valves in the bottles.

[underlined] Economiser & Flowmeters [/underlined]
1/. Inside rear turret starbd. side.
2/. Lavatory post. port side.
3/. Starb. side above flare chute.
4/. Port side mid-upper turret.
5/. Starb. side rest position.
6/. Opposite F.E.’s position starb. side.
7/. Port side by F.E.’s panel (fire controller).
8/ Port side behind instrument panel.
9/ Starb. side behind instrument panel.
10/ Port side rear of W/Op.
11/ Port side bomb aimers position.

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[underlined] Portable Oxygen Bottles [/underlined]
1/. Port side forward of rear turret.
2/. Starbd. side above flare chute.
3/. Starb. rest position.
4/. Below F.E.’s panel.
5/. Starbd. side opposite F.E.’s position.
6/. Under W/Op’s seat.
7/. Starbd. side bottom of steps.
8/. Starbd. side opposite B/A’s prone position.

[Diagram]

1. Supply stop cock & charging valve closed
2. Remove cap on transport cylinder & connect transport cylinder to charging rig & charging rig to outside charging valve on A/C.
3. Stop cock on charging rig closed

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4. Fit key to valve on transport cylinder, & open slowly one full turn. (2 to 3 mins)
5. Check pressure in transport cylinder on guage [sic] no 1.
6. Open stop cock on charging rig slowly, & check pressure on guage [sic] no 2. This should read 1900 lbs [symbol]” if not adjust on regulator ‘in to increase’, ‘out to decrease.’
7. Open charging valve on A/C slowly. Check pressure in system from time to time by closing stop cock on charging rig & checking pressure on guage [sic] no. 2. Charging takes 30-40 mins.
After charging disconnect, closing charging valve on A/C first, then stop cock on charging rig & then valve on transport cylinder. Disconnect charging rig from A/C & transport cylinder from charging rig.

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[underlined] PORTABLE FIRE EXTINGUISHERS. [/underlined]

1/. Starbd. side forward of rear turret.
2/. Starb. side above flare chute.
3/. Starb. side rest position.
4/. Below F.E.’s panel.
5/. Rt. hand side of pilot to rear.
6/. Starb. side bottom of steps to navigators position.
7/. Above navigators head.

[underlined] FIRE DRILL [/underlined]
1./ Pilots throttle backs & push constant speed unit lever through the gate.
2/ Air bomber will press feathering switch.
3/ F.E. will turn off pilots control fuel cock, close radiator shutters, turn off cabin heating if an inboard engine & re-select a further combination of fuel tanks.
4/ When prop is fully feathered & not until then will pilot press fire extinguisher button.

FINIS.

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[underlined] SCHOOL [/underlined]

[underlined] Boost Pressure [/underlined]
Is the pressure in the induction system above or below 14.7 lbs [symbol]”

[underlined] Reasons for supercharging. [/underlined]
1/ To increase the power output of an engine of given size by increasing the induction pressure above 14.7 lbs [symbol]”.
2/ To maintain this increase of pressure up to some fixed altitude.

[underlined] Limiting Operational Conditions Merlin XX [/underlined]

[Table]

The power of the Merlin XX increases up to full throttle at constant boost & revs. due to
1/ Reduction of back pressure on exhaust gives

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better scavenge.
2/ Decrease in air temp. increases wt. of charge. If boost is less than +4 lbs. throttle lever must be fully open.
If boost is +4 lbs. throttle lever must short of gate with 1800 revs at about 4000 ft.

[underlined] Remarks [/underlined]

Min. coolant 60°C Min. oil 25°C.
Max. coolant 125°C Max. oil 90°C. Rads open. (also used as emergency cruise, oil temp. may rise 105° 5 mins only)
Max. coolant 125°C Max oil 90°C

Max. coolant 105°C Max. oil 90°C
Max coolant 105°C Max. oil 90°C

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[underlined] PERFORMANCE [/underlined]
[underlined] Range Flying [/underlined]:- This is the normal method of operating a Halifax & it means flying to obtain the max. number of miles for each gallon of petrol. This is done by doing the least possible work per mile. Work done = Force x Dist;
So the work done per miles will be least when the drag is least. To maintain steady horizontal flight the Lift = Wt. [symbol] Drag is least when the L/D ratio is a maximum, i.e. when flying at optimum.

[Diagram]

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In practise the [symbol] of attack is not used so much as the air speed indicator. If we are flying at the optimum angle at the laden weight of 5500 lbs. then there is only one possible speed for steady horizontal flight. – It is 150 I.A.S.
[symbol] If we are flying at this speed we must be getting max. range.
On the return journey the lift required is less. [symbol] If we keep at the optimum angle we must fly at a slower speed. It is 135 I.A.S.

[Diagram]

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[Diagram]

From the curves which show the relation between AMPG & IAS it will be seen that there is very little loss in range when flying at a speed 10 mph greater when laden & 15 m.p.h. greater when light than most economical. At these higher speeds the A/C control is easier & also the job is completed in a shorter time [symbol] these speeds are recommended for use if they can be obtained in M gear & in a weak mixture.

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[underlined] The Affect [sic] of Altitude on Range Flying. [/underlined]
As altitude increases the distance travelled per hour at a constant IAS increases but the drag remains the same [symbol] the work done per hour increases & so does the H.P. required. If we assume that the petrol used per hour is proportional to the H.P. the petrol consumption will increase at the same rate as the distance travelled [symbol] the AMPG will not vary with altitude. Thus if we are flying in M gear with fully open butterflies, in a weak mixture & on the green band then the AMPG will be independant [sic] of altitude.

Q1. How many gallons are required for a 790 track mile trip?
Gals. required = [calculation] [symbol] 200
= [calculation] [symbol] 200

= 1000 [symbol] 200

= 1200 gals.

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Q2. What will 1200 gals. of petrol weigh?
1200 x 7.2 1 gal weighs 7.2 lbs.
[calculation] 1 gal of oil 9 lbs.

Q3. What is the all-up wt. (A.U.W.) of the Hx carrying 1200 gals of petrol & 9000 lbs of bombs?

Tare wt. of Hx = 35,942 lbs.
Typical service load = 3638 lbs.
Oil (112 gals) = 1008 lbs.
Petrol (1200 gals) = 8640 lbs.
[underlined] Bombs & carriers [/underlined] = [underlined] 9900 [/underlined] lbs.
A.U.W. 59,128 lb.

Q.4 How far can a Hx fly on its full wing tanks & what bomb load can it then carry assuming an AUW of 60,000 lbs.
Can carry 1886 gals.
[calculation]

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[calculations]

Q.5 How far can a Hx carry its [deleted letter] max. bomb load of 7 tons.

[calculations]

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Q.6 Suppose you are recalled having left with an A.U.W. of 59,000 lbs & 3000 lbs of bombs. What petrol must be consumed in order to land safely at a max. safe landing load of 50,000 lbs.

A.U.W. 59,000 lbs
Safe Landing Load 50,000 lbs
Must lose 9,000 lbs
Bombs jettisoned 3,000 lbs.
Petrol to lose 6000 lbs.

[calculation] = 833 gal.

[underlined] Duration Flying [/underlined]
This means flying for the maximum possible length of time with no attempt to cover large distances. The condition is obtained by cutting the gallons per hour fuel consumption to a minimum by reducing the H.P. used to the lowest possible. It is obtained in practise by

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reducing the A/C speed to the lowest at which the pilot still has satisfactory control. It may be aided by taking the flaps 1/3 out, this speed should normally lie between 100 & 150 I.A.S. according to load.

[underlined] The Effects of Altitude on Duration Flying [/underlined]
For control the pilot must maintain a certain min. I.A.S. & the power required to do this will increase with altitude [symbol] the fuel flow in g.p.h. increases with altitude being least at sea-level. Hence max. duration is obtained by flying at the lowest altitude & the slowest IAS at which the pilot has satisfactory control.

[underlined] Climbing. [/underlined]
In a climb the T.H.P. developed by the engines is divided between T.H.P. required to move the A/C forward against drag & THP lift to lift A/C. To get a high rate of climb the lifting H.P. must be large which means as little H.P. as possible is to be used against drag. This will mean that the forward speed must be cut

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down to a minimum, but if it is cut below 145 I.A.S. cooling control becomes difficult. Thus the Halifax is best climbed at 145 I.A.S.
The A/C must be kept at this speed entirly [sic] by the use of elevators & trimming tabs, the engines must be set to deliver max. power i.e. +9 2850 revs. for a rich emergency climb, +4 2650 revs for an economical climb & +5 to +7 2650 revs for an intermediate climb.

A Halifax is cruising efficiently at 5000 ft. [indecipherable mark] 5000 ft in M. gear at 156 IAS, [deleted word] requires 2640 B.H.P. Find (a) B.H.P. per engine (b) boost & revs required. (c) air miles per gal.

R.A.S. = 156 + 4 = 160
TAS = 160 x 1.08 = 1728 miles
AMPG = [calculation] = 1.01
= [underlined] 1.00 [/underlined]

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A Hx is flying in M gear at 145 (+5) requires 2260 B.H.P. at 12000 ft.
RAS = 145 + 5 = 150
TAS = 150 x 1.2 = 180
AMPG = [calculation] = [underlined] 1.2 [/underlined]

2000 ft in M gear at 145 +5, 2580 B.H.P.
R.A.S. = 145 + 5 = 150
T.A.S. = 150 x 1.2 = 180
AMPG = [calculation] = [underlined] 1.04 [/underlined]

[Calculations]

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[Calculations and Table]

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[Table]

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[underlined] Gear Change. [/underlined]

(a) In a climb. The gear which gives the greatest M.P. is always the gear to use. In an emergency climb +9 2850 ‘S’ gear is engaged when the boost in M has fallen to 6 1/2 lbs.

In an economical climb +4 2650 S gear is engaged when the boost in ‘M’ has dropped [deleted letters] lbs or the rate of climb is unsatisfactory when +5 to +7 in S gear is used to maintain a satisfactory rate of climb.

(b) In cruising. S gear is used for cruising when you cannot get on to the green band in M on less than 2600 rpm.

[underlined] Cruising Rules [/underlined]:-
1/ Cruise normally in ‘M’ gear with max. possible boost up to +4.
2/ Control I.A.S. entirely with R.P.M. to get on to the green band. Leave the throttle lever at the gate
3/ Use ‘S’ gear only if you cannot get on to green band in ‘M’ on less than 2600 r.p.m.

[page break]

4/ Only use warm air intake if cold air intake is blocked with ice or snow.

COOLANT TEMPS
MIN. for run up 60°
MIN for T.O. 80°
MAX FOR T.O. 120°
Normal working 85°-95°

OIL TEMPS
MIN. for run up 25°
MIN for T.O. 40°
Normal working 50-60
Max temp. 95°

OIL PRESSURES
Normal 70° - 95 lbs
Min. 45 lbs.
Heywood Air Compressor H & C intakes & brakes. P bank.
RAE Air Compressor Auto Pilot & M XIV bomb sight.

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HOURS FLOWN –
TOTAL FUEL USED –
AV. TAS –
TOTAL MILES –
AV. AMPG TOTAL MILES/FUEL USED
AV. GPH FUEL USED/HOURS FLOWN

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[Blank page]

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17/ Where are engine starter relays fitted.
18/ If a relay failed to operate how would you remedy the trouble.

[Calculations]

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[Blank page]

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Ground running checks
Pre-flight inspection
Fuel
Feathering

[Calculations]

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How far can a Hx carry a 8000 lb. bomb.

[Calculations]