Armstrong Whitworth Ensign
| A.W.27 Ensign | |
|---|---|
 |
|
| AW.27 Ensign G-ADTC in typical 1940 markings | |
| Role | Airliner |
| Manufacturer | Armstrong Whitworth Aircraft |
| First flight | 24 January 1938 |
| Introduction | 1938 |
| Retired | 1946 |
| Primary users | Imperial Airways BOAC |
| Number built | 14 |
The Armstrong Whitworth Ensign was a British four-engine airliner built during the 1930s for Imperial Airways. It could seat 40 passengers and was designed for European and Asian routes, connecting Britain with further seaplane flights to Australia and South Africa.
Contents |
[edit] Design and development
Armstrong Whitworth Aircraft started on the A.W.27 Ensign in 1934 after receipt of a specification from Imperial Airways. The first aircraft was ordered in September of that year, with delivery expected in 1936; 11 more were ordered in May 1935.[1] An order for a further two aircraft in 1937 brought the total to 14.
The Ensign was a high-wing cantilever monoplane of light alloy construction and an oval, semi-monocoque fuselage with a conventional tailplane. It had retractable landing gear and a castoring tail wheel. The main landing gear was hydraulically operated and retracted into the inner engine nacelles. The cockpit had side-by-side seating for two pilots with dual controls; there was also accommodation for a radio operator. The fuselage was divided into separate cabins, either four cabins with accommodation for 40 passengers or three cabins with room for 27 by day or 20 at night with sleeping accommodation.[2]
Production of their Whitley heavy bomber for the Royal Air Force was a priority, and work on the Ensign proceeded slowly. Construction took place not at the main Coventry factory, but at the workshops of Air Service Training Ltd in Hamble. Constant changes were requested by Imperial, slowing production further. As a result, the Ensign's maiden flight did not take place until 24 January 1938.[3] Despite being underpowered, the aircraft was certified, and full airline service began between Croydon Airport and Paris, France in October of that year.
[edit] Operational history
Three more Ensigns were completed by Christmas 1938, and were dispatched to Australia with the holiday mail.[1] All three suffered mechanical problems and did not reach their destination;[3] consequently, all Ensigns were removed from active airline service and returned to Armstrong for improvements. Reliability was improved, and more powerful Armstrong Siddeley Tiger IXC engines aided performance somewhat.
A total of 11 aircraft were in service at the outbreak of the Second World War, with a 12th following soon after, and all were withdrawn in October 1939; they were to be camouflaged before flying a new route from Heston Aerodrome to Le Bourget Airport, Paris. The aircraft remained in service after formation of BOAC that November. Three Ensigns were destroyed or captured due to enemy action in 1940, with one ("Ettrick"), which had been abandoned at Le Bourget after being damaged by bombs, eventually being used by the Germans, being re-engined with Daimler-Benz[3] engines.
The final two aircraft that had been ordered by Imperial were equipped with more powerful Wright Cyclone geared radial engines and completed as A.W.27A Ensign Mk 2s. The new engines significantly improved performance and allowed the Ensign to be used in hot climates and at high altitude. All eight surviving airframes were upgraded with these newer engines in 1941-43 and worked for BOAC on Africa to India routes.
Ensigns flew throughout the war. One ("Enterprise") force-landed in West African Vichy territory and served the Vichy forces and Air France, until it was scrapped in Toulouse in 1943. Several were broken up for spare parts to support the remaining fleet. The final Ensign flight took place in 1946, and the last seven aircraft were scrapped in 1947.
[edit] Accidents and incidents
- On 23 May 1940, G-ADTA Euryalus crash-landed at RAF Lympne and was damaged. The aircraft was one of six that escaped after a Luftwaffe raid on Merville Airfield, France. The intended destination was Croydon. Approaching the English coast, first she lost her port inner engine and the pilot set course for RAF Hawkinge. A short time later her starboard inner engine also had to be shut down. The pilot changed course for Lympne. On landing, the starboard undercarriage was not fully down, causing the wing to scrape the ground and the aircraft to go through a fence as no braking as attempted. Euryalus was flown to RAF Hamble in June, but it was decided to cannibalise her to repair G-ADSU Euterpe which had been damaged in an accident at Bonnington on 15 December 1939. Euryalus was officially written off on 15 November 1941 and scrapped in September 1942.[4]
[edit] Variants
- A.W.27 Ensign I
- Four-engine medium-range transport aircraft. Powered by four 850 hp (630 kW) Armstrong Siddeley Tiger IXC radial piston engines.
- A.W.27A Ensign II
- Four-engine medium-range transport aircraft. Powered by four 950 hp (710 kW) Wright GR-1820-G102A Cyclone radial piston engines.
[edit] Operators
[edit] Civil operators
[edit] Military Operators
[edit] Specifications (A.W.27A)
Data from Jane's Fighting Aircraft of World War II[2]
General characteristics
- Crew: 5 (captain, first officer, radio operator, two cabin stewards)
- Capacity:
- European routes: 40 passengers in 4 cabins
- Asian routes: 27 passengers in 3 cabins
- Length: 114 ft (34.8 m)
- Wingspan: 123 ft (37.5 m)
- Height: 23 ft (7.02 m)
- Wing area: 2,450 ft² (227.6 m²)
- Empty weight: 35,075 lb (15,900 kg)
- Loaded weight: 55,500 lb (25,200 kg)
- Useful load: 12,000 lb (5,450 kg)
- Powerplant: 4 × Wright GR-1820-G102A geared radial engines, 1,100 hp (820 kW) each
Performance
- Maximum speed: 210 mph (180 kn, 330 km/h)
- Cruise speed: 180 mph (160 kn, 290 km/h)
- Range: 1,370 mi (1,190 nmi, 2,200 km) at 5,000 ft (1,500 m)
- Service ceiling: 24,000 ft (7,300 m) when fully loaded
- Rate of climb: 900 ft/min (4.57 m/s)
- Wing loading: 22.6 lb/ft² (110 kg/m²)
- Power/mass: .079 hp/lb (130 W/kg)
[edit] See also
- Related development
- Aircraft of comparable role, configuration and era
- Related lists
[edit] References
- Notes
- ^ a b "Armstrong Whitworth A.W.27 Ensign." Imperial Airways, 20 April 2006. Retrieved: 31 January 2011.
- ^ a b Bridgman 1988, pp. 103–104.
- ^ a b c Jackson, A. J. British Civil Aircraft since 1919, Volume 1. London: Putnam & Co., 2nd Edition 1973. ISBN 0-370-10006-9.
- ^ "Ensign Class". Flight (15 February 1957): pp. 203–206. (p203, p204, p205, p206)
- Bibliography
- Bridgman, Leonard. Jane's Fighting Aircraft of World War II. New York: Crescent Books, 1988. ISBN 0-517-67964-7.
[edit] External links
|
||||||||
|
||||||||||||||
