The end of the war brought about a considerable reorganization of the
Royal Air Force, in particular Bomber Command, which was about to
introduce the Lancaster B. Mark IV and B. Mark V into service. The post-war RAF decided to keep the B. Mark I (FE) for service in the Middle East and Far East, whilst ‘standard’ aircraft would serve with Bomber Command at home.
Lancaster B. Mark VII (FE)
Power:
As per B. Mark I
Dimensions:
As per B. Mark I
Weight:
As per B. Mark I except for an all-up weight of 72,000lb
Performance:
As per B. Mark I
Armament:
Early aircraft: 8 .303 Browning machine guns in power-operated turrets: 2 in FN5
nose, 2 in FN50 mid-upper and 4 in FN20 rear turrets
Main production run: 2 .303 Browning machine guns in power-operated FN5 nose turret and 4 Browning .50 machine guns; 2 in electrically operated Martin frameless mid-upper turret and 2 in Fraser Nash FN82 rear turret
12,000lb bomb load
Serials:
NN801, NX548-NX589, NX603, NX610, NX611-NX648, NX661-NX703, NX715-NX758, NX770-NX794, RT670-RT699
Production:
Austin Motors: 230
The Lancaster B. Mark VII was intended from the outset for ‘Tiger Force’.
Austin Motors built the prototype B. Mark VII, NN801, which was the
forerunner of 230 aircraft built by Austin Motors at Longbridge.
The B. Mark VII was externally similar to the B. Mark I. The main visible difference was the replacement of the FN50 mid-upper turret with a Martin frameless unit. The mid-upper turret on the B. Mark VII was moved forward to a position just aft of the trailing edge of the wing. The new position caused some difficulty with crew movement fore and aft, but increased the ease of access and escape for the mid-upper gunner. The supply of the American
Lancaster B. Mark VII (FE)
Martin turret was delayed and so the first four aircraft (NX548, NX589, NX678 of IX Squadron,
NX603 and NX610) were fitted with the FN50 turret in the new position
Salbani, India in 1946. The
intended for the Martin unit and the FN20 tail turret. These aircraft were Mark VII (FE) mainly saw
classified as Lancaster B. Mark VII (interim). The Martin unit became available service overseas with the RAF
after the war.
for the main production run, at which time the tail turret was also replaced with the Nash and
Thompson FN82 rear
turret equipped with two
Browning .50 machine
guns.
All the B. Mark VII
(FE) aircraft saw service
overseas prior to the end
of World War II, except
for NX558, which was
sent to A. V. Roe for trials.
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Lancaster A.S.R./G.R./MR. 3
Lancaster A.S.R. 3 (later GR3)
PB641 was originally built as a
Technical Details:
All details as per Lancaster B. Mark III
B. Mark III but was converted
Armament:
6 Browning .303 machine guns in power-operated turrets: 2 in FN5 nose and 4
to A.S.R. 3 standard in 1945.
in FN20 tail turrets
The H2S blister (fitted to all
ASR aircraft) has the rear
The end of the war in Europe left the Royal Air Force with a gap in its inventory.
portion unpainted.
The RAF had been mainly dependent upon American aircraft to fulfil its
maritime requirements in Coastal Command, which had been returned or
disposed of under the terms of the lend-lease agreement with the United States.
This left the RAF without a maritime reconnaissance or long-range Air Sea Rescue (ASR) aircraft.
A number of Lancasters had been used by Coastal Command during the
war for maritime reconnaissance, and whilst the crew had to rely on visual surveillance, the airframe proved suitable for the needs and stresses associated with long-range maritime patrol.
To fill the gap in the RAF’s inventory, a number of Lancaster B. Mark IIIs from the RE, RF and SW serial blocks were converted by Cunliffe Owen for the A well-used Lancaster GR.3, Air Sea Rescue role. The conversion removed the mid-upper turret and fitted SW336 of No. 38 Squadron.
The window in the crew entry
external attachments to hold a life boat suspended under the bomb bay. A door was not present in other window was added each side of the fuselage forward of the tail plane to improve marks of Lancaster.
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This Lancaster B. Mark I
(Modified) is one of the
aircraft modified for use by
the French Aeronavale in
1948. The aircraft is in all over
blue with French roundels.
This colour image of a French
Aeronavale Lancaster shows
the later all over white scheme
and roundel markings. Of
interest is the lack of
armament in the turrets. A
further five were ordered by
the French Aviation Civile et
Commerciale (Civil and
Commercial Aviation) in 1952.
The aircraft were allocated the
serials FCL01 to FCL05 and
were delivered in early 1954.
visibility for observation. All the ASR conversions were fitted with H2S.
The RAF still struggled with its maritime role and in 1947 the lack of a General Reconnaissance/Maritime Reconnaissance aircraft led to the
conversion of ASR Lancasters to General Reconnaissance (GR) machines. The GR machines were fitted with ASV radar in the H2S radome and a rear-facing camera was added in a pod under the rear turret. A change in role (and title) occurred in 1950 when the aircraft were retitled MR (Maritime Reconnaissance) aircraft, by which time Lincoln-style undercarriages were beginning to be found on some of these aircraft. The MR Lancaster would soldier on in the role until it was replaced by its younger sister the Shackleton.
Lancaster Mark I (modified)
The Lancaster B. Mark I (modified) was in all technical respects identical to a standard B. Mark I. Under the terms of the Western Union Agreement of 1948, the French Aeronavale (Naval Air Arm) was to be equipped with surplus
Lancaster B. Mark I and B. Mark VII aircraft modified to undertake maritime reconnaissance. The aircraft were converted at A. V. Roe and were all
designated as Lancaster Mark I (modified). The modifications made to the aircraft reflected peacetime requirements. The dorsal turret was removed and 38
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replaced with escape hatches. Extra fuel tanks were fitted in the bomb bay to extend the range of the aircraft to meet the needs of long maritime patrol missions. Advanced specialist equipment was fitted inside the aircraft to meet the needs of a maritime role. All the aircraft were allocated WK serials, the first WK-01 being handed over to the Aeronavale in January 1952, with a total of 58 aircraft being converted.
Lancaster B. Mark IV and B. Mark V
Power:
B. Mark IV: 4 Rolls-Royce Merlin 85
B. Mark V: 4 Packard Merlin 68A
Dimensions:
Span: 120ft
Length: 78ft 3in
Height: 17ft
Wing area: 120ft
Weight:
All-up weight: 75,000lb (B. Mark IV)
Performance: Maximum speed: 319mph at 12,500ft (B. Mark IV)
Service ceiling: 30,500ft (B. Mark IV)
Range: 1,470 miles (B. Mark IV)
Armament:
B. Mark IV: 4 .50 Browning mac
hine guns in power-operated turrets: 2 in Boulton Paul ‘F’ nose turret and 2 in Boulton Paul ‘D’ tail turret. 2 20mm Hispano cannon in Bristol 17 mid-upper turret.
14,000lb bomb load.
The Lancaster B. Mark IV and the B. Mark V were designed to meet Air
Ministry requirement B.14/43. The requirement called for a large bomber to be powered by four two-stage, two-speed Merlin engines. The new aircraft was expected to be capable of operating at altitudes up to 35,000ft and to have an all-up weight of 70,000lb.
In response to B.14/43, Roy Chadwick proposed a modified Lancaster
airframe. The fuselage was lengthened by inserting an 8ft-long section into the fuselage, and the nose was changed to a design based upon a modified nose trialled on Lancaster ED371, which accommodated the bomb aimer in a
seated position rather than the prone position required in the previous marks of Lancaster, about which Bomber Command had expressed some
dissatisfaction. The new nose replaced the bomb aimer’s blister with a new framed, flat-panelled bomb-aiming blister, a new seat and improved equipment for the bomb aimer, as well as an improved turret. The Lancaster wing was Lincoln B2 RF398 at the RAF
extended with new outer wing sections, which increased the aircraft’s wingspan 50th Anniversary Royal
to 120ft to enable the aircraft to meet the new performance requirements laid Review, 7 June 1968.
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This wartime Lancaster
diagram shows the positions
of the H2S and Gee equipment
when fitted.
down in B.14/43. The fuel capacity of the wing tanks was also increased to 3,500 gallons.
The team at A. V. Roe gave consideration to the defensive armament of the Lancaster, and as a result the B. Mark IV and B. Mark V were equipped with a new nose turret, which mounted a pair of Browning .50 machine guns and a new tail turret that also mounted a pair of Browning .50 machine guns. Most importantly, the equipment of the dorsal turret was radically changed with the introduction of a new turret, which was positioned just aft of the wing trailing edge and mounted a pair of 20mm Hispano cannon. The new Lancaster
packed quite a punch when she needed to defend herself.
In order to cope with the increased weight and offensive performance of the new mark of Lancaster the undercarriage was changed to a more robust design, and the bomb bay was modified.
The new design became the Avro Type 694, and was initially known as the Lancaster B. Mark IV with Merlin 85 engines and the Lancaster B. Mark V
with Merlin 68A engines. The design had numerous changes to its predecessor, and whilst it resembled the Lancaster in general layout and still retained the large twin oval tail fins associated with the Lancaster, it was a very different machine. A. V. Roe wanted to change the name to reflect the fundamentally new design, but Bomber Command was keen to keep the Lancaster name. In
June 1944 A. V. Roe suggested three possible new names for the Type 694, Sandringham, Stafford and Lincoln. J. D. Breakey ACAS (TR) commented that Lincoln was an appropriate name, as it not only reflected the current convention of naming bombers after cities in Britain, but also reflected the area in which the Lancaster had been operated by Bomber Command. The new name was
officially approved in August. The Lancaster B. Mark IV became the Lincoln B. Mark I and the Lancaster B. Mark V became the Lincoln B. Mark II. Bomber Command would not get its new bomber until after World War II ended, even though it had been designed from the outset with service in the Far East in mind. The first prototype Lincoln PW925 first flew in June 1944, but events reduced the need to rush the new aircraft into service. In 1944 the successful Lancaster was viewed as perfectly adequate for operations in 1945, and
production of Lancasters to meet Bomber Command’s needs left no spare
manufacturing capacity to dedicate to Lincoln production. The situation in 40
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Europe and the Pacific was improving in favour of the Allies, and thus the need for a new bomber was reduced and its production became a low priority.
The need for large numbers of bombers disappeared after the end of the
war, and many production orders for Lincolns were cancelled. Despite this, over 500 Lincolns were built, and the aircraft would serve the Royal Air Force well into the 1950s, some examples seeing service with Argentina and Australia.
The last Lincoln retired from RAF service in 1963.
Specialist equipment
It is necessary to discuss the specialist equipment fitted to Lancasters as a separate subject to the discussion of types since not all aircraft of one mark were fitted with the same specialist equipment; for example, not all B. Mark I aircraft were fitted with H2S. The section that follows briefly discusses some of the specialist equipment fitted to Lancasters.
Gee
Gee was designed to assist navigation and to permit ‘blind’ bombing when the target was not visible to the bomb aimer. It relied on reception of signals from a series of ground stations, the master (A) and two slaves (B and C) along a 200 mile baseline. The time difference between receiving the signals from A and B and B and C were displayed on a unit in the aircraft. The navigator could calculate a ground position by referencing the display to a special ‘Gee Chart’, which gave a result accurate to within five and a half miles. Only a limited number of aircraft were fitted with Gee and typically led bomber streams to targets within the operating range of Gee, dropping their bomb load, which mainly consisted of incendiaries, to mark the target.
Oboe
Oboe was the most accurate of the navigation systems used during World War II.
It was needed because Gee could be, and was, jammed. Oboe was eventually jammed by the German defences too. Oboe was designed in 1941, based on
two ground stations. The first, called ‘cat’, sent out a dot-dash signal, the second, called ‘mouse’, sent out a release signal, both signals operating on the same wavelength but at different pulse frequencies. A repeater in the aircraft responded to both frequencies, allowing each station to measure the aircraft’s range. If on track, a steady tone would be heard by the pilot, allowing him to adjust his course if necessary. The system was only used in the target area.
H2S
H2S was probably one of the most effective pieces of equipment used by
Bomber Command during World War II. It consisted of an airborne interception radar that was fitted under the aircraft to point at the ground. Returning pulses were displayed on a cathode ray tube in the navigator’s position, known as the Plan Position Indicator. H2S gave a radar map of the terrain that the aircraft was flying over and ahead of its path. The navigator was able to use the map to get a fix of where the aircraft was. H2S was not affected by weather, cloud or jamming and was completely independent of ground stations.
Lancasters fitted with H2S are extremely easy to identify. The H2S set was installed in a large, clear Perspex blister on the underside of the fuselage just aft of the bomb bay. The blister was sometimes painted in the underside colour for the forward two thirds of its length, with the rear third left clear. The first 41
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three Lancasters fitted with H2S were
B. Mark IIIs, JB352, JB355 and
JB356 in November 1943. The H2S
system did have one fault; German
night fighters could be guided to an
H2S-fitted aircraft by ‘listening’ to
the H2S emissions using Naxos sets.
G-H and Loran
G-H was effectively an Oboe set
working in reverse, the aircraft
transmitting the signals that were
received by mobile ground stations to
give a fix. More aircraft could be on
the G-H system simultaneously than
could on Oboe, but accuracy
>
depended heavily on the ability of the
This image of a Lancaster
aircrew. The system was used first on the night of 3 November 1943 during a suggests a non-operational
raid on Dusseldorf by 344 Lancasters, of which 38 were G-H-equipped. By night. The circle in the blister
October 1944, one third of No. 3 Group’s Lancasters was fitted with G-H.
is the bomb aimer’s flat glass
G-H-fitted Lancasters are also easy to identify, as their tail fins were painted aiming panel. The two aerials
on the underside are probably
in different colours to make identification easier for other aircraft so that Gee or Oboe aerials. The lack
non-G-H-fitted Lancasters could follow them to the target.
of a blister aft of the bomb
Loran was developed in the United States for long-range navigation over bay indicates that this aircraft
the sea. It used pairs of transmitting stations that gave the navigator a single is not fitted with H2S.
position at a time, the navigator alternating between stations on 1-minute cycles to get a fix. It was used from 1944, when Gee sets were modified to allow them to switch between Gee and Loran.
Electronic warfare
A number of electronic warfare systems were fitted to Lancasters in varying quantities during World War II. Some were restricted to aircraft of No. 100
Group, which was dedicated to electronic countermeasures against the
German defence forces’ equipment, whereas other systems were fitted to
main force Lancasters.
Window was fitted to all main force Lancasters, and consisted of aluminium foil strips cut to precise lengths that would interfere with German ground radar by presenting multiple false targets. Window was initially dropped through the aircraft’s flare chute by hand, but later a Window distribution box was fitted to the fuselage side. Another ‘jamming’ device was Tinsel, which was also fitted to main force Lancasters and involved fitting a microphone into one engine nacelle. From this, engine noise would be broadcast on the frequencies used by night fighters to communicate with their ground stations, making it impossible for the fighter to be guided to an intercept position. Mandrel was another device fitted to main force Lancasters, which produced a signal that saturated the German early-warning Freya radar sets.
Avro Lancaster Page 6