authorized while the aircraft was still in the design stage, an order
for 80 aircraft being placed in August 1935. Alan Campbell-Orde flew
the first prototype (K4586) at Whitley Abbey on 17 March 1936, the
machine's two Armstrong Siddeley Tiger X engines turning the then new
three blade variable pitch de Havilland propellers. A second prototype
built to Specification B.21/35 had the more powerful 795 hp (593 kW)
Armstrong Siddeley Tiger IX 14-cylinder radial engines driving three
bladed two-pitch propellers and was flown by Charles Turner Hughes on
24 February 1937.
The speed of the
aircraft’s construction had led to some compromises in its design.
Although the fuselage was a modern aluminium monocoque design, the wing
wasn’t. It was built in three pieces around a huge box spar; with
structures formed from aluminium sections attached front and rear,
which were then clad in a mixture of non-structural aluminium sheets
and fabric. This was a heavier arrangement than the more modern, but
less understood stressed skin construction. The wing was also set at a
huge incidence angle of 8.5 degrees to reduce the aircraft’s angle of
attack while landing. The late addition of hydraulic landing flaps had
made this unnecessary, but it was by then too late to change. In level
flight this high wing incidence caused the fuselage to fly several
degrees nose down, thereby increasing drag. Trials at the Aircraft and
Armament Experimental Establishment at Martlesham Heath were undertaken
in the autumn of 1936, The first production Whitley Mk Is were
delivered early in 1937, including the second aircraft which was flown
to RAF Dishforth on 9 March for No. 10 Squadron. Thirty-four Mk Is
where built before the Whitley Mk II was introduced. This mark had
Tiger VIII engines with two speed superchargers, the first fitted to an
RAF aircraft; 46 Whitley Mk IIs completed the initial order for 80
Mk I and Mk II Whitleys
had Armstrong Whitworth manually operated nose and tail turrets, each
with a 7.7 mm (0.303 in) Vickers machine gun, but in the Whitley Mk III
the nose turret was replaced by a power operated Nash and Thompson
turret, and a retractable ventral turret with two 7.7 mm (0.303 in)
Brownings was added. The 80 Whitley IIIs also had modified bomb bays to
accommodate larger bombs then being introduced in the RAF.
By far the most
numerous of the Whitley variants were those with Rolls-Royce engines. A
Whitley Mk I was fitted with Merlin IIs and test flown at Hucknail on
11 February 1938, although engine failure prematurely concluded the
second flight. The program was quickly resumed, however, and during
April and May the aircraft carried out trials at Martlesham Heath.
Rolls Royce Merlin IV
12-cylinder Vee liquid-cooled engines rated at 1,030 hp (768 kW) for
take-off and 990 hp (739 kW) at 12,250 ft (3740 m) driving Rotol
constant speed propellers were installed on production Whitley IVs, the
first of which flew on 5 April 1939. Other changes incorporated in this
version included a power operated Nash and Thompson tail turret with
four 7.7 mm (0.030 in) Browning machine guns. A transparent panel was
added in the lower nose to improve the view for the bomb aimer, and two
additional wing tanks were fitted to bring the total capacity to 705
Imperial Gallons (3205 litres). Production totalled 33, together with
seven Whitley Mk IVAs which had 1,145 hp (854 kW) Merlin X engines.
The same engines were
retained for the Whitley V, which incorporated a number of
improvements. The most noticeable of these were modified fins with
straight leading edges and an extension of 1 ft 3 in (0.38 m) to the
rear fuselage to provide a wider field of fire for the rear gunner.
Rubber de-icing boots were fitted to the wing leading edges, and fuel
capacity was increased to 837 Imperial Gallons (3805 litres) or 969
Imperial Gallons (4405 litres) if extra tanks were carried in the bomb
bay. Production totalled 1,466 aircraft.
The Whitley VI was a
projected version with Pratt & Whitney engines, studied as an insurance
against a possible short supply of Merlin engines. It was not built,
however, and the ultimate production Whitley was the Whitley Mk VII
which was essentially a Mk V with auxiliary fuel tanks in the bomb bay
and in the rear fuselage to bring the total capacity to 1,101 Imperial
gallons (1333 US gallons or 5000 litres) increasing the range to 2,300
miles (2701 km) for maritime patrol duties. Externally the Mk VIIIs
could be distinguished by the dorsal radar aerials of the ASV Mk II
Air-to-Surface radar. Production reached 146 aircraft, and some Mk Vs
were converted to this standard.
As noted above, No. 10
Squadron at RAF Dishforth was the first to equip with the Whitley,
which replaced the Handley Page Heyford in March 1937. Nos. 51 and 58
Squadrons at RAF Leconfield soon followed and during the night of 3
September 1939, ten Whitley IIIs from these two squadrons flew a
leaflet raid over Bremen, Hamburg and the Ruhr. Just under a month
later during the night of 1 October, No. 10 Squadron flew a similar
mission over Berlin. The first bombs were dropped on Berlin during the
night of 25 August 1940, the attacking squadrons including Nos. 51 and
78 with Whitleys. To mark the entry of the Italians into the war, 36
Whitleys drawn from Nos. 10, 51, 58, 77 and 102 Squadrons were tasked
to raid Genoa and Turin during the night of 11 June 1940, although only
13 aircraft actually reached their targets due to a combination of
inclement weather and engine troubles.
The Whitley retired
from Bomber Command in April 1942, the last operation being flown
against Ostend during the night of 29 April, although some aircraft
from operational training units were flown in the "1,000 Bomber" raid
on Cologne on the night of 30 May 1942.
association with the Whitley began in September 1939 when No. 58
Squadron was transferred to Boscombe Down to operate anti-submarine
patrols over the English Channel. This lasted until February 1940 when
the unit returned to Bomber Command, but during 1942 it took up patrol
duties once again, flying over the Western Approaches from St Eval and
Stornoway. Other units similarly occupied at that time included Nos. 51
and 77 Squadrons, the latter operating in the Bay of Biscay area.
Mk V Whitleys replaced
the Avro Ansons of No. 502 Squadron at RAF Aldergrove in the autumn
of1940 and a second Coastal Command Whitley unit, No. 612 Squadron,
formed in May 1941. The Mk Vs were replaced by the ASV Mk II equipped
Whitley VII, and an aircraft of No. 502 Squadron sank the type's first
German submarine when it attacked U-206 in the Bay of Biscay on 30
Whitleys were also used
at No. 1 Parachute Training School at Ringway, Manchester, and were
adapted for use as glider tugs, becoming attached to No. 21 Glider
Conversion Unit at Brize Norton for the training of tug pilots. The
paratroop raid on the German radar site at Bruneval used Whitleys of
No. 51 Squadron and the aircraft of special duty units at RAF Tempsford
(Nos 138 and 161 Squadrons) flew numerous sorties, dropping agents into
occupied territory and supplying Resistance groups with arms and
equipment. Fifteen Whitley Vs were handed over to BOAC in May 1942 and
stripped of armament but additional fuel tanks in the bomb bays, few
regularly from Gibraltar to Malta carrying supplies for the beleaguered
(Armstrong Whitworth A.W.38 Whitley B.Mk V)
Type: Five Seat
Long Range Night Bomber
A crew of five consisting of a Pilot, Navigator/Bomb-aimer,
Radio/Wireless Operator and 2 gunners.
Armstrong Whitworth Design Team
Sir W. G. Armstrong Whitworth Aircraft Limited based in Coventry. The
company was formed in 1921. In 1935, the Hawker Siddeley Aircraft
Company Limited was formed to amalgamate the interests of Hawker
Aircraft Limited and the Armstrong Siddeley Development Company Limited
which which the later company controlled Sir W. G. Armstrong Whitworth
Aircraft Limited, Armstrong Siddeley Motors Limited and the A. V. Roe &
Company Limited. The company was a pioneer in the development of
all-metal aircraft, and it is due to their initiative that the use of
high-tensile steel became prominent.
(B.Mk V) Two Rolls Royce Merlin X 12-cylinder liquid-cooled engines
each rated at 1,075 hp (802 kW) for take-off and 1,130 hp (843 kW) at
5,250 ft (1525 m) at 3,000 rpm. (B.Mk IV) Two Rolls Royce Merlin IV
12-cylinder liquid-cooled engines rated at 1,030 hp (768 kW) for
take-off and 990 hp (739 kW) at 12,250 ft (3740 m) driving Rotol
Maximum speed 230 mph (370 km/h) at 16,400 ft (5000 m); cruising speed
210 mph (338 km/h) at 15,000 ft (4572 m); service ceiling 26,000 ft
(7925 m) with a normal operational ceiling of between 17,600 - 21,000
ft (5400 - 6400 m). Initial climb rate of 800 feet (244 m) per minute;
climb to 12,000 ft (3660 m) in 21 minutes.
837 Imperial gallons (1,005 US gallons or 3804.5 litres), plus
provision for up to 132 Imperial gallons (160 US gallons or 600 litres)
in auxiliary weapon-bay fuel tanks.
Range: With a
3,000 lbs (1361 kg) bombload, range was 1650 miles (2655 km) on
internal fuel (standard) of 837 Imperial Gallons (4405 litres). Range
could be increased to 1908 miles (3072 km) with the addition of extra
tanks carried in the bombay that raised the total fuel carried to 969
Imperial Gallons (5096 litres). With a full 7,000 lbs (3175 kg) loadout
range dropped to about 470 miles (756 km).
19,350 lbs (8777 kg) with a nominal take-off weight of 28,200 lbs
(12789 kg) maximum take-off weight of 33,500 lbs (15195 kg).
84 ft 0 in (25.60 m); length 70 ft 6 in (21.49 m); height 15 ft 0 in
(4.57 m); wing area 1,137 sq ft (105.63 sq m); wing aspect ratio 6.21;
mean chord 14 ft 4 in (4.37 m).
A (Nash and Thompson) F.N.16 nose turret was equipped with a single
Vickers 'K' machine-gun using the 97 round drum-type magazine and four
7.7 mm (0.303 in) Browning machine guns in a powered (Nash and
Thompson) tail turret using ammunition belts which supplied 1,000
rounds per gun.
Up to 7,373 lbs (3344 kg) of bombs could be carried in the two fuselage
bays and 14 inner and outer wing bomb cells. Each fuselage bay was
capable of carrying 2,000 lbs (907 kg) and each wing bomb cell could
carry a single 250 lbs (113 kg) bomb. The two fuselage bays could be
modified to carry a single 2,000 lbs (907 kg) armour-piercing bomb.
Normal ordnance loadout however, was limited to the following:
2 x 500 lbs (227 kg)
and 12 x 250 lbs (113 kg) bombs
16 x 250 lbs (113 kg)
4 x 420 lbs (191 kg)
depth charges (GR.Mk VII)
2 x 420 lbs (191 kg)
depth charges and 4 x 250 lbs (113 kg) anti-shipping bombs (GR.Mk VII)
The normal bombload was
4,000 lbs (1814 kg) made up of 2 x 500 lbs (227 kg) and 12 x 250 lbs
(113 kg) bombs carried in the fuselage with extra fuel in the bomb
cells in the wings. One of the few instances where the Whitley carried
its maximum bombload was the attacks against German invasion barges on
the French coast.
Whitley, Whitley B.Mk I, Whitley B.Mk II, Whitley B.Mk III, Whitley
B.Mk IV, Whitley B.Mk IVA, Whitley B.Mk V, Whitley C.Mk V (frieghter),
Whitley Mk VI (never built), Whitley GR.Mk VII (naval conversion),
Whitley GR.Mk VII (ASW).
Standard communication and navigation equipment. The Mk.VIIc or Mk.IXc
bombsight was also standard. After 1942 most surviving aircraft were
fitted with glider towing equipment. Two cannisters could be fitted
under the wings for leaflet dropping raids. (GR.Mk VII) ASV Mk II
flight (prototype) 17 March 1936; first delivery (Mk I) January 1937;
first flight (Mk V) December 1938; first delivery (Mk V) August 1939;
production terminated in June 1943; final operational sortie 29 April
1942 against Ostend.
United Kingdom (RAF, BOAC).
Units: On 9
March 1937 the second production aircraft was delivered to RAF Dishford
were it equipped No. 10 squadron, the first squadron to use the type.
At its peak of use the Whitley equpped nine RAF Bomber Squadrons Nos.
7, 10, 51, 58, 77, 78, 97, 102, 166. The Whitley would also equip two
RAF Coastal Command Squadrons Nos. 502 and 612.