LANCASTER I, III & X

NOTES TO USERS

This publication is divided into six parts: Descriptive, Handling, Operating Data, Emergencies, Supplementary Notes for Flight Engineer, and Illustrations and Location of Controls.

These Notes are complementary to A.P. 2095 Pilot's Notes General and assume a thorough knowledge of its contents. All pilots should he in possession of a copy of A.P. 2095 (see A.M.O. A93/43). Flight Engineers should alsO have a copy of A.P. 2764 when issued.

Words in capital letters indicate the actual markings on the controls concerned.

Additional copies may be obtained from A.P.F.S., Fulham Road, S.W.3, by application on R.A.F. Form 294A, in duplicate, quoting the number of this publication in full— A.P. 2062A, c and f—P.N.

Comments and suggestions should be forwarded through the usual channels to the Air Ministry (D.T.F.).

DESCRIPTIVE

INTRODUCTION. The Lancaster I, III, VII and X are heavy bombers, the difference between them being mainly in the power plants. The Lancaster I is fitted with Merlin XX. 22 or 24 engines, which have SU carburettors ; the Lancaster VII is the Austin built version of the Mark I, with Merlin 24 engines, having the Glenn Martin 250 CE 23 turret installed in the forward mid-upper position. The Lancaster III and X are fitted with Merlin 28. 36 or 224 engines, which have Bendix Stromterg pressure-injection carburettors; hydromalic propellers are fitted to all marks. Lancaster X are Canadian built and differ from British-built Lancasters in some of the instruments and in the electrical system. The Lancaster Mk. III with Mod. 1480 incorporated is known as the Lancaster ASR Mk. III. Mod. 1480 introduces navigational equipment and suitable gear for dropping an airborne lifeboat.

2. Fuel tanks.—Three self-sealing tanks are fitted in each wing, numbered 1, 2 and 3 outboard of the fuselage between the front and rear spars. On some aircraft the tanks may be marked Inner, Centre and Outer instead of Nos. 1, 2 and 3. The positions are:

No. 1 (Inner): Between the fuselage and the inner engines

No. 2 (Centre): Between the inner and the outer engines

No. 3 (Outer): Outboard of the outer engines.

Capacities are:

Port and starboard No. 1: 580 gallons* each

Port and starboard No. 2: 383 gallons each

Port and starboard No. 3: 114 gallons each

                1,077 gallons each side

                2,154 gallons each in all

Provision is made on some aircraft for carrying one or two 400-gallon tanks fitted in the bomb cells; these tanks are connected so that their contents may be transferred into either or both No. 1 wing tanks and thence to-the engines. When the maximum bomb load is carried, the No. 2 tanks should be filled first, and the remainder of the fuel put in No. 1 tanks. This is on account of strength considerations of the aircraft structure.

3. Fuel cocks.—The pilot controls four master engine cocks (24, 30). On Lancaster I aircraft, the master engine cocks also control the slow-running cut-outs. The flight engineer controls two tank selector cocks (77) which select No. 1 or No. 2 tank on each side. (No. 3 tank replenishes No. 2, see below). A cross-feed cock (marked BALANCE COCK) connects the port and starboard supply systems, and is on the floor just forward of the front spar, with the handle visible through a hole in the spar cover.

When the 400-gallon tanks are fitted in the bomb cells they each have an ON-OFF cock situated behind the front spar in the centre of the fuselage.

4. Vapour vent system (Lancaster III and X aircraft only).

A vent pipe from each carburettor is connected to the No. 2 tank on the same side of the aircraft, and allows vapour and a small quantity of fuel (approx. ½ gal. per hour, per carburettor, but some later carburettors may have a second vent allowing 10 gallons per hour) to return to the tank. This carburettor is designed to work full of fuel, and it therefore requires the vent to carry away any petrol vapour and dissolved air. It also assists in re-establishing the flow of fuel to the carburettors when the pipe-lines and pump have been run dry due to a tank emptying.

5. Electric fuel booster pumps

(i) Originally, on Lancaster I aircraft, immersed pumps were fitted in all tanks; Mod. 594 (temporary) removed the immersed pumps from No. 1 tanks and fitted stack pipes in their places.

A later Mod. 512 put back the immersed pumps in No. 1 and No. 2 tanks and incorporated suction by-pass lines to allow fuel to be drawn from the tanks when the pumps are not in use. In aircraft incorporating Mod. 539, including all Lancaster III aircraft, a Pulsometer FB Mk. I pump is fitted in each tank and by-pass lines are incorporated at No. 1 and No. 2 tanks. On Lancaster X aircraft, Thomson pumps, similar to the Pulsometer pumps, and by-pass lines are fitted.

No. 3 tank is used to replenish No. 2 tank (see Figs. 5 & 6) by switching on the No. 3 tank pump. When the 400-gallon tanks are fitted in the bomb cells they each have a similar pump fitted to transfer their contents to the No. 1 tanks,

(ii) The main use of the electric fuel pumps in No. 1 and No. 2 tanks is to maintain fuel pressure at altitudes of approximately 17,000 ft. and over in temperate climates, but they are also used for raising the fuel pressure before starting and to assist in re-startiiig an engine during flight. If one engine fails during take-off and the electric fuel pump is not ON, air may he crawn back into the main fuel system before the master engine cock of the failed engine can be closed, thus causing the failure of the other engine on the same side; therefore at take-off the pumps in Noe. 1 and 2 tanks must be switched on; this is also a precaution against fuel failure during take-off as an immediate supply is available by changing over the tank selector cock. The pump in each tank in use should also be switched on at any time when a drop in fuel pressure is indicated or when it is necessary to run all engines from the tank by opening the cross-feed cock

6. Fuel contents gauges. - On Lancaster I and III, the switch (76) on the flight engineer`s panel must be set ON before the fuel contents gauges will indicate. On Lancaster X there is no fuel contents gouge switch; the gauges will indicate whenever electrical power is available. Mods. 1198 and 1384 introduce "Gallons-gone" fuel flowmeters which are also under the control of the flight engineer.

7. Fuel pressure indicators — Fuel pressure warning lights (79) show when the fuel pressure at the carburettor falls below 6 lb./sq.in. on Lancaster I aircraft, and 10 lb./sq.in. on Lancaster III aircraft. They are switched off by the fuel contents gauges switch (76), and this switch must, therefore, always be on in flight. On Lancaster X, fuel pressure gauges (73) are fitted on the flight engineer's panel. They will indicate whenever battery power is available.

8. Priming pumps. — There is one cylinder priming pump in each inboard engine nacelle, drawing fuel from the No. 1 tank on that side; each pump serves one inboard and one outboard engine. On Lancaster I, III and VII aircraft this is accomplished by having two priming cocks fitted in each nacelle. On Lancaster X the priming pump handle is turned to the left to prime the left engine, to the rignt to prime the right engine, and to the mid-position for off.

On Lancaster I, III and VII the pruning pumps may be type K40 (40 ccs.) with a T-handle, or A.M. type B (10 ccs.) with a round handle. The American type priming pumps fitted on Lancaster X have approximately the same capacity as the A.M. type B pump. Another cock und a short pipe may be fitted beside Lie priming pump and can be used to connect an outside supply of high volatility fuel for cold weather starting.

9. Oil tanks. — Each engine has its own tank capasity 37½ gallons of oil with 4½ gallons air space.

10. Oil dilution. — The four push-buttons (81) are on the flight engineer's panel.

* The fuel capacities are given in Imperial gallons.
- 1 Imperial gallon=4.546 L ; 1 US gallon=3.785 L

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