Airspeed Ambassador

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Airspeed AS.57 Ambassador
Airspeed AS.57 Ambassador
Type: Airliner
Design country:

United KingdomUnited Kingdom United Kingdom

Manufacturer:

Airspeed

First flight:

July 10, 1947

Commissioning:

1951

Production time:

1947-1953

Number of pieces:

23

An Ambassador in Liverpool in 1961

The Airspeed AS.57 Ambassador was a twin-engine British airliner manufactured by Airspeed , which was powered by two piston engines and 23 copies were built from 1947. Although the type equipped with a pressurized cabin enjoyed great popularity with passengers, the aircraft designed for 50 passengers was only rarely used.

The design of the Ambassador was based on the proposal IIA of the Brabazon Committee , which provided a twin-engine short-haul airliner for use between Great Britain and Western Europe.

history

As early as 1938, Airspeed had a design called “Ambassador” (AS14), which was also designed as a twin-engined shoulder-wing aircraft. However, the project did not get beyond the design phase.

In 1945 work on the prototype of the AS.57 began at Airspeed , a subsidiary of the de Havilland Aircraft Company . The machine with the aircraft registration G-AGUA made its maiden flight on July 10, 1947 . The second prototype with the registration G-AKRD flew for the first time on August 26, 1948. Two cells were used for strength tests. The prototype was powered by two Bristol Centaurus 631 engines, each with 2600 hp (1913 kW ).

The third prototype G-ALFR, which was equipped with the Centaurus 611 engines intended for the production version, was used for the acceptance flights to obtain air traffic approval. This aircraft, which made its maiden flight in May 1950, was used on an experimental basis by British European Airways (BEA) on its route network.

With an order for twenty AS.57s in 1948, the BEA ordered its last type of airliner with piston engine drive . The first aircraft intended for the airline completed its maiden flight on January 12, 1951. The test flights came to an end in August 1951 with the issuance of the license to operate, but it was not until March 13, 1952 that the BEA put the new type of aircraft known as Elizabethan on its route network in service.

Besides the BEA, there was no other buyer for the AS.57, which is why production was discontinued after the 20th machine had been delivered.

Various development projects existed under the designation AS.59, including a turboprop drive with four Dart propeller turbines for the model. Other interesting projects include the AS.60 Ayrshire, a military transporter designed according to specification 13/45, and the freighter AS.67, but none of these projects was realized.

Since 2013 the only remaining, restored machine has been exhibited in the English Imperial War Museum Duxford (G-ALZO).

construction

The passenger cabin was designed for the transport of a maximum of 50 passengers. Since the aircraft was designed as a shoulder- wing wing , the passengers had a good view from the large, rectangular windows.

The aircraft type was extremely easy to maintain, as the engine cowlings could be opened in all directions when working on the engines. In addition, the complete engines with the associated units could be exchanged as a unit. The Ambassador was also characterized by good short take-off properties and above-average flight performance, even with just one engine.

use

It quickly became apparent that the AS.57 caused the lowest operating costs of all aircraft types in the BEA fleet, especially on short routes. Nevertheless, the AS.57 was after only six years of service from the more advanced turboprop pattern Vickers Viscount replaced and led on 30 July 1958 the last scheduled flight by.

After being withdrawn from BEA, three aircraft flew in Australia with Butler Air Transport, two more were acquired by Swiss Globe Air and another pair was taken over by the Jordanian Air Force for VIP transport tasks. In the 1960s, however, all AS.57s returned to Great Britain, where they were still in service for around ten years as passenger and cargo aircraft for the non-essential airlines Dan-Air London (three copies), Autair and BKS Air Transport .

Two AS.57s were used by Shell Petroleum as business jets and an Ambassador was used by the Decca Navigation Company as a demonstration aircraft for avionics . The second prototype G-AKRD and the series machine G-ALZR were used at times as flying test stands for testing the propeller turbines Napier Eland, Bristol Proteus and the Rolls-Royce types Dart and Tyne .

Airlines

Incidents

BKS used the Ambassador (G-AMAD), which had an accident in London in 1968, to transport horses

From the first flight in 1947 to the end of the mission, the Airspeed Ambassador suffered seven total losses. In two of them, 29 people were killed. Full list:

  • On April 8, 1955, six minutes after the start of an ambassador for British European Airways ( aircraft registration G-AMAB ), an engine failed, which caused the pilots to return and make an emergency landing at Düsseldorf Airport . The go-around due to poor visibility ended in a crash landing 9 km outside the airport. All 53 people on board survived the accident.
  • On April 14, 1966, a Dan-Air ambassador (G-ALZX) touched down very late on landing in Beauvais-Tillé , rolled over the end of the runway and collided with a pile of earth. The machine was damaged beyond repair. All 59 inmates survived.
  • On September 14, 1967, a Ambassador rolled over (G-ALZS) of Autair after landing at the airport Luton the end of the runway. The aircraft was written off as a total loss. All 69 occupants of the machine were uninjured.
  • On July 3, 1968, an Ambassador (G-AMAD , serial number 5211) used by BKS Air Transport as a cargo plane had an accident while landing at Heathrow Airport . The aircraft crashed into two parked Hawker Siddeley Tridents , one of which was destroyed, and then crashed into Terminal 2. Six of the eight occupants were killed in this accident. The cause was a fatigue fracture on the landing flap drive, which caused the left landing flap to retract and trigger an uncontrollable rolling movement.
  • On September 30, 1968, the right main landing gear could not be locked on a training flight with the G-AMAG of Dan-Air . The pilots evaded to Manston Airport and belly landed there on a foam carpet . The machine was then beyond repair, but both crew members survived.
  • On July 26, 1969, the nose landing gear of an Ambassador (G-ALZR) of BKS Air Transport broke on a cargo flight while landing at London-Gatwick Airport . Due to the amount of damage, the machine was written off as a total loss; the eight people on board were not injured.

Technical specifications

Airspeed Ambassador
Parameter Data
crew 3 + 2
Passengers 47-60
length 25.05 m
span 35.05 m
height 5.60 m
Takeoff mass 23,814 kg
Cruising speed 415 km / h
Service ceiling 7,600 m
Range 2,200 km
Engines two air-cooled 18-cylinder radial engines Bristol Centaurus 661 , 2625 PS (1929 kW)

See also

Web links

Commons : Airspeed AS.57 Ambassador  - Collection of pictures, videos and audio files

Individual evidence

  1. ↑ Airplane Monthly, December 2003, p. 18
  2. ↑ List of accidents with Airspeed AS.57 Ambassador , Aviation Safety Network WikiBase , accessed on November 25, 2019.
  3. ^ Accident report Airspeed Ambassador G-AMAB , Aviation Safety Network (English), accessed on January 28, 2016.
  4. ^ Accident report Airspeed Ambassador G-ALZU , Aviation Safety Network (English), accessed on November 25, 2019.
  5. ^ Accident report Airspeed Ambassador G-ALZX , Aviation Safety Network (English), accessed on January 28, 2016.
  6. ^ Accident report Airspeed Ambassador G-ALZS , Aviation Safety Network (English), accessed on January 28, 2016.
  7. ^ Accident report Airspeed Ambassador G-AMAD , Aviation Safety Network (English), accessed on January 28, 2016.
  8. ^ Accident report Airspeed Ambassador G-AMAG , Aviation Safety Network (English), accessed on January 27, 2016.
  9. ^ Accident report Airspeed Ambassador G-ALZR , Aviation Safety Network (English), accessed on January 28, 2016.