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Elegant and offering pressurized cabin comfort, the Airspeed AS.57 Ambassador found a brief niche with BEA British European Airways, whose image was elevated because of it. A crash with Manchester United Team defined an otherwise mid-century airliner
Design Origins of the Airspeed AS.57 Ambassador
As had occurred in other parts of the world, sights set on World War II’s end signaled a beginning—in this case, of commercial aviation no longer interrupted by conflict and the development of passenger, cargo, and mail aircraft optimized for it.
Taking its name from Lord Brabazon of Tara, the Brabazon Committee was established in Britain to study the emerging markets and then determine the most suitable types to serve them, whether powered by piston, turboprop, or pure-jet engines.
Aircraft Was Designed To Replace The DC-3 and Vickers Viking
One encompassed European routes, on which the Douglas DC-3 and the Vickers Viking had mostly been deployed, but their replacements needed to incorporate increased seating and the latest technical advancements.
Airspeed was selected to fill the Brabazon Committee’s Type 2A requirement.
Founded in Yorkshire by Alfred Hessel and Neville Shute Norway, both of whom were airship engineers, in 1931, it entered the aerial stage with its AS.1 Tern, a small glider which attracted publicity because of its record-breaking flights. It was followed by its first powered airframe, the ten-passenger AS.4 Ferry, which featured two de Havilland Gipsey II engines and a third upper wing-mounted Gipsey III.
Airspeed Was Formed
Renamed Airspeed (1934) Limited that very year after it was financially-supported by Swan Hunter Wigham Richardson, Ltd, Tyneside Shipbuilders, it was able to embark upon a more ambitious design program, eventually producing the AS.6 Envoy, the AS.8 Viceroy, and the AS.10 Oxford.
“With the outbreak of war in September 1939, Airspeed found itself with a range of aircraft which did not meet the beckoning requirements of the Royal Air Force (RAF), and in 1940 it was announced that de Haviland Aircraft Company had purchased a controlling interest in Airspeed (1934) Limited,” according to BAE Systems.
It was subsequently chosen to manage the Ministry of Aircraft production facility in Christchurch, New Zealand, one of Britain’s commonwealth countries.
Although it concentrated on the production of de Havilland types, such as the Mosquito, the Sea Vixen, and the Vampire, it was tasked with developing Britain’s first purposefully-designed post-war airliner.
“Entered upon in 1943, the Airspeed AS.57…had been seen as belonging to a second post-war generation to replace improvised aircraft or types not ideally suited to the routes, which would be hurried into operation when the war ended,” advises C. Martin Sharp in DH: A History of de Havilland (Airlife, 1982, p. 287).
Design Features of the Airspeed AS.57 Ambassador
Resembling, in overall configuration, the Fokker F.27 Friendship and the Handley Page Herald of the day, the AS.57 Ambassador featured a clean, all-metal, almost circular cross section fuselage with an 82-foot length. Low to the ground, it facilitated boarding, loading, servicing, and maintenance.
One of its cornerstones was its thin, high-aspect ratio, high-mounted, 115-foot wing, which increased speed, decreased drag, and afforded unobstructed passenger views from the cabin.
Power was ultimately provided by two 2,625-hp wing-installed, nacelle-encased, 18-cylinder, two-row Bristol Centaurus 661 radial engines, whose advantages were many.
- A large power reserve in the event of engine loss.
- A high cruise speed.
- The ability to in- or decrease cruise speed based upon departure delay or other-airline competition on the same route.
Yaw axis control was achieved by means of three vertical fins and drag was decreased with a retractable tricycle undercarriage.
How Many People Could the Airspeed AS.57 Ambassador Carry?
Airspeed initially considered 40-passenger four-abreast and 60-passenger four- and five-abreast internal configurations in a pressurized cabin.
How Fast Could The Airspeed AS.57 Ambassador Fly?
Speed varied from a 260-mph cruise to a 312-mph maximum. Range was 550 miles, sufficient for most continental European routes.
An Elegant Design
“The Airspeed AS.57 Ambassador was an elegant, high-wing, two piston-engine airliner design with triple tail fins,” according to BAE Systems’ “Airspeed Ambassador: The Elizabethan Class Airliner of the 1950s” entry. “It had its origins in the Brabazon Committee’s Type 2A (category), originally calling for a piston-powered short-haul feederliner intended to replace the Douglas DC-3 to Ministry Specification 25/43.”
Two prototypes were authorized and their performance was seen as leading to airline interest and orders.
Flight Test Program Ready To Launch The New Airspeed AS.57 Ambassador
Powered by two 2,400-hp Bristol Centaurus 631 engines and piloted by Chief Test Pilot George B. S. Errington and Flight Engineer John Pear, the first prototype, registered G-AGUA, took to the air from Christchurch on July 10, 1947 still in unpressurized form. Although its 45-minute maiden mission could be labeled “satisfactory,” it revealed a few shortcomings, including less-than-effective ailerons and the need for additional flight control development.
The second prototype, G-AKRD, featured both pressurization and a fixed tail bumper to minimize under-fuselage damage in the event of runway strikes when it first flew in August of 1948. But while the airfoils of both were designed to increase lift, they revealed that they required additional strengthening, which delayed the program.
The type’s pressurization was tested when a fuselage was submerged in Portsmouth Docks, located only a short distance from the production plant.
Launched With An Order For 20 Aircraft
BEA, which placed a 3 million British pound launch order for 20 aircraft on September 23, also provided input about needed modifications for its routes, particularly a 47-passenger interior.
A third prototype, conforming to an Ambassador 2, introduced the more powerful Bristol Centaurus 661 engines and gross weight increase from 45,000 to 52,500 pounds. This was later increased to 55,000 pounds.
Airspeed AS.57 Ambassador Enters Service
Having principally operated smaller, earlier-generation aircraft, such as the Vickers Viking and the Douglas DC-3, BEA eagerly needed the larger, more modern Ambassador to enhance its image and cater to greater demand, particularly on the well-traveled continental routes, during the summer of 1951.
Because the modification-caused delays hindered timely delivery, it temporarily operated a loaned example, registered G-ALZN, replacing some of its Vikings between Northolt and Paris.
Delivery of its first full-production standard aircraft, G-ALZS, enabled it to enter a new chapter in its history. As the largest, most modern, and luxurious type it ever operated, it emphasized its newly-introduced prestige by dubbing it “Elizabethan Class,” and each was named after a notable figure from the Elizabethan era. It was inaugurated into service between London and Paris-Le Bourget on March 13, 1952.
Initial Success
Although it progressively replaced its Vikings with AS.57s and took delivery of all 20 ordered aircraft by March of the following year, it introduced all-first-class Silver Wing service on certain routes.
“The Elizabethan Class was an instant success, so other key routes were quickly introduced and at one point, the Ambassador became BEA’s most used aircraft, each attaining more than 2,230 flying hours per annum,” according to BAE Systems.
In its April 17, 1955 timetable, by which time it had already begun to take delivery of turboprop-powered Vickers Viscounts, it advertised, “Fly BEA Silver Wing: First Class services to Paris, Brussels, and Lisbon,” the first two of which were served with Ambassadors.
“Elizabethan airliners leave London Airport daily at 1:00 p.m.—flying time one hour, 20 minutes,” its timetable further noted. “Daily return service leaves Paris at 12:30 p.m.” The Brussels flight departed at 12:45. “Special ‘Silver Wing’ lunch served,” it emphasized.
An aircraft schematic indicated a three-person cockpit crew consisting of the captain, the first officer, and the radio officer; a forward galley and baggage compartment; a 47-passenger cabin with some rear-facing seats; and an aft wardrobe, toilet, and freight hold. Its “Elizabethan” aircraft, it stated, were de Havilland-Airspeed AS.57s, of which it operated twenty.
Tragedy Strikes With Manchester United On Board
Although the type was involved in a few nonfatal mishaps, its record was shattered on February 6, 1958 when aircraft G-ALZU, chartered by Manchester United and operating as Flight BE 609, failed to achieve airborne speed at the Munich-Riem Airport.
After beating Red Star Belgrade and making it through to the European Cup’s semi-finals, the football players boarded the AS.57, which made an intermediate refueling stop in Germany.
Under the command of Captain James Thain, it twice conducted its acceleration run, only to be twice aborted because its engines failed to achieve their full power output.
Despite mounting snow and slush, the crew elected to make a third takeoff attempt, now penetrating near-blizzard conditions. Plowing through speed-inhibiting accumulations, it was unable to reach its rotation speed and careened through a fence and into a house instead.
“Thick flames began to envelop the plane…the house caught fire before a hut filled with tires and fuel exploded,” according to Tom Herbert’s “Munich Air Disaster” coverage of the crash in the London Evening Standard.
Of the six crew members and 38 passengers on board, two of the former and 21 of the latter perished, and it took a decade to exonerate the captain, who was initially accused of attempting the takeoff without proper deicing, before the probable cause was ultimately determined as obstructing surface conditions.
Program Conclusion
In order to market the Ambassador, P. E. Gordon-Marshall of the de Haviland business department was appointed to the Airspeed board, but de Havilland itself acquired control in 1948 and fully absorbed it three years later.
“The Airspeed spirit remained, and nothing did more to keep it alive than the stalwart service which the fleet of Ambassadors…gave it for five to six years on the routes of BEA, albeit under the name Elizabethan, which the airline bestowed on it,” according to Sharp (op. cit., p. 289).
After those five or six years, it began to replace its AS.57 fleet with faster, turboprop-powered Viscounts, to which its passengers flocked when given the choice, leaving it to operate its last revenue service on July 30, 1958.
Nevertheless, as the type’s only original carrier, it was able to claim many achievements—namely, it resulted in lower operating costs, a decline in time needed for maintenance, higher load factors than those experienced by any other aircraft it had flown up to the summer of 1957, and a longer service life of its Bristol Centaurus engines than that of any other powerplant it had employed.
In March of 1957, it recorded a 71.9-percent load factor on its Ambassador flights and during the five years preceding it, its fleet had accumulated 151,741 airborne hours.
Second-hand examples were subsequently acquired by the likes of Autair International, BKS Air Transport, and Dan-Air.
Program Discontinued
While it was originally envisioned as offering turboprop power in a later version, de Havilland, increasingly focused on pure-jet Comet development, discontinued the program after two Ambassador 1 prototypes, a single Ambassador 2 prototype, and 20 production-standard Ambassador 2s had been produced.
Sole Survivor That You Can Still See Today
Aircraft G-ALZO, first delivered to BEA on November 25, 1952, became the last to survive, although only in static form.
After its initial operator career, it was used for VIP and transport flights by the Royal Jordanian Air Force in 1960 and then acquired by Dan-Air three years later, at which time it was retrofitted with a rear fuselage cargo door by Marshall of Cambridge, enabling it to undertake passenger and freight flights. The aircraft operated the type’s last scheduled service on September 28, 1971.
“It was then retired to the Dan-Air Maintenance Base at Lasham,” according to the British Airliners Collection website. “It remained at Lasham until 1986, when it was donated to the British Aircraft Collection and transported by road to Duxford. After long-term restoration in its Conservation Hangar, it was rolled out to join the other airliners in the collection in April 2013.”
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