LANCASTER I, III & X

47. Position error correction

(i) All handling speeds are quoted for aircraft without H2S blister with the pilot's ASI connected to the static vent in the port side of the fuselage. The position error correction is —1 m.p.h. at all speeds from 140 m.p.h. I.A.S. upward.

(ii) When H2S blister is fitted, the position error correction for static vent is as follows :

(iii) For early aircraft in which the static vent connection has not been made correction is as follows :

(iv) On Lancaster ASR Mk. III the corrections are as follows:

(a) When the lifeboa: is being carried, the correction is +3 m.p.h. I.A.S. at speeds below and +2 m.p.h. at speeds above 160 m.cb.

(6) When the lifeboat is not being carried the correction varies from +1 m.p.h. at 110 m.p.h. IAS. to -1 m.p.h. at 250 m.p.h. I.A.S.

48. Maximum performance

(i) Climbing:

160 m.p.h. I.A.S. to 12,000 ft.

155 m.p.h. I.AS. from 12,000 to 18,000 ft.

150 m.p.h. l.A.S. from 18,000 10 22,000 ft.

145 m.p.h. l.A.S. above 22,000 fl.

Change to S ratio when boost has fallen to +6 lb./sq.in.

(ii) Combat.— Use S ratio if the boost obtainable in M ratio is more than 3 lb./sq.in. (4 Ib./sq.in. with Merlin 24 or 224) below maximum combat boost.

49. Maximum range

(i) Climbing — 160 m.p.h. I.A.S. at +7 lb./sq.in. boost with

Merlin 22, 24, 28, 38 or 224 -f 4 ib./sq.in. with

Merlin XX, and 2.650 r.p.m. Change to S ratio when maximum boost obtainable in M ratio has fallen by 3 Ib./sq.in.

(ii) Cruising (including descent):

(a) Fly in M ratio at maximum obtainable boost not exceeding +4 lb./sq.in. with Merlin XX, + 7 lb./sq.in. with Merlin 22,24,28,38 or 224 obtaining the recommended airspeed by reducing r.p.m. which may be as low as 1,800 if this will give the recommended speed. Higher speeds than those recommended may be used if obtainable in M ratio at the lowest possible r.p.m.

(b) The recommended speeds are:

Fully loaded (outward journey):

Up to 15,000 ft., 170 m.p.h. I.A.S.

At 20,000 ft. in S ratio, 160 m.p.h. I.A.S.

Lightly loaded (homeward journey):

160 tn.p.h. I.A.S.

(c) Engage S ratio when the recommended speed cannot be maintained at 2,500 r.p.m. in M ratio.

(iii) The use of warm intakes will reduce air miles per gallon considerably. On this installation there is no need to use warm air unless intake icing is indicated by a drop of boost. Set A.P. 2095—Pilot's Notes General.

50. Fuel capacity and consumptions

(i) Capacity: Two No. I lanks .. 1,160 gallons

Two No. 2 tanks .. 766 gallons

Two No. 3 tanks .. 228 gallons

Total .. 2,154 gallons

(ii) Weak mixture consumptions. Merlin XX,-22 or 24:

The following figures are the approximate total gallons per hour and apply in M ratio between 8,000 and 17,000 feet, and in S ratio between 14,000 end 25,000 feet.

* - These figures do not apply to Merlin XX.

(iii) Weak mixture consumptions Merlin 28 and jSfngines:

The following figures are the approximate total gallons per hour for the aircraft and apply in M ratio at 5,000 ft. and S ratio at 15,000 ft. One gallon per hour should be added for every 1,000 ft. above these heights.

(iv) Rich mixture consumption. Merlin XX. 22, 24:

* Merlin XX only.

(v) Rich mixture consumptions, Merlin 28, 38:

51. Engine failure during take-off

(i) If for any reason tho booster pumps in the tanks being used are not ON the master fuel cock of the failed engine must bo turned off before feathering.

51A Instrument approach

The following speeds. together with the appropriate flap and approxnate power settings, are recommended for use during instrument approaches with the undercarriage lowered:

51B. Flying in turbulent conditions

In turbulent conditions the aim should be to maintain a speed of approximately 160 knots.

The pilot should, however, press the fire-extinguisher button as well, when the propeller has stopped turning. If the warning light is not on, pressing the feathering pushbutton will not operate the extenguisher. The fire extenguisher are also operated automatically by crash switch.

(iii) Handling oh three engines. The aircraft will maintain height at loads up to 65,000 lb. on any three engines at 10,000 feet, and can be trimmed 10 fly without fool load. Maintain at least 145 m.p.h. I.A.S. The automatic pilot has sufficient power to maintain a straight course with either outboard engine out of action, but only if assisted by the rudder trimming tab. When an engine fails the automatic pilot should, however, be disengaged and the aircraft trimmed to fly hands off before re-engaging. See A.P. 2095.

(iv) Landing on thret engines.—Lowering of flaps to 20° and of undercarriage may be carried out as normally on the circuit but further lowering of the flaps should be left until final straight approach, which should be made at a speed of 110-115 m.p.h. I.A.S.—see A.P. 2095.

(v) Handing on two engines.— It should be possible to maintain height below 10,000 feet at 140 m.p.h. I.A.S. on any two engines after release of bomb; and with half fuel used ; but with two engines dead on one side, the foot load will be very heavy. The automatic pilot will nol cope with flight with two engines dead on one side.

(vi) Landing on two engines.— A left-hand circuit can safely be made, and is recommended, irrespective of which engines have failed. Keep extra height in hand, if pouiblc, and lower the undercarriage as late as practicable, aiming to have it locked down just before commencing the straight approach to the airfield. The flaps may be lowered 20° before the undercarriage is lowered but they should not be lowered further until it is clear that the airfield is within easy reach. The final approach should be nude at a speed of 115-120 m.p.h.- I.A.S. See A.P. 2095.

may be necessary in the early stages. [See A.P. 2095, Part IV, Notes C and D.) (vii) Do not attempt lo maintain height above 10,000 feet,

(vii) Do not attempt to maintain height above 10,000 feet, either on three or two engines.

(viii) Fuel system.— The cross-feed cock ihould only be turned on when it is desired to feed fuel from port (or starboard) tanks to starboard (or port) engines, in this case all live engines should be fed from one tank and the fuel booster pump for this tank should be un. The tuel selector for the tanks on the other side of the aircraft should be off. At all other times, the cross-feed cock should be off.

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