The Airspeed Ambassador was an all metal twin engine airliner, designed to serve short-to-medium haul routes.
It was considered to be relatively advanced for the era, being a relatively aerodynamically clear aircraft with features such as a high aspect ratio wing with near Laminar flow characteristics, a tricycle undercarriage, a steerable nose wheel, integral fuel tanks, and other recent innovations.
Distinctive external features of the Ambassador included its three low tailfins and a long pointed nose, it shared something of the character of the larger transcontinental Lockheed Constellation.
In a standard configuration, the Ambassador was could accommodate a maximum of 47 passengers, somewhat unusually, its passenger cabin could be either pressurised or not, dependent on the preference of the specific customer.
It was typically powered by conventional Bristol Centaurus radial engines, although individual aircraft were re-engine with various power plants, including turboprops.
In order to achieve a high level of efficiency while cruising, its designers made great efforts to minimize drag.
These included the use of a NACA laminar flow wing section, although structural features for wing construction, propeller slipstream over the inner wing and increasing skin roughness with service were amongst several factors that reduced the optimistic NACA section’s performance when measured in a wind tunnel.
The engine nacelles were initially designed with inwardly-opening louvers for exhaust gases and cooling air rather than the usual outwardly opening “gills”.
However, these proved inadequate for cooling the engine, thus the gills were reinstated.
Engine out climb performance was enhanced by being able to feather the propeller using a zero-torque signal from the engine.
Up to 60 passengers
81 ft (25 m)
115 ft (35 m)
18 ft 4 in (5.59 m)
1,200 sq ft (110 m2)
35,884 lb (16,277 kg)
Max take-off weight
52,000 lb (23,587 kg)
1,000 imp gal (1,200 US gal; 4,500 l) in two integral wing tanks, with provision for 600 imp gal (720 US gal; 2,700 l) in two centre-section bag tanks