Airspeed AS-4 Ferry

This was a multi engined airliner to requirements of Sir Alan Cobham. The wings were equal span, three bay, unstaggered, unswept biplane configuration. Wings were of constant chord. Lower wing is cranked to shorten undercarriage leg. Construction of wood with fabric covering. Ailerons on all four wings. Wings braced from engine mount to lower fuselage. The fuselage under the lower wing was box section monocoque of spruce and of plywood construction. The pilot was in an enclosed cockpit in the nose with an enclosed cabin for 10 passengers behind.

Power Plant:
Two 120 hp de Havilland Gipsy II four cylinder upright engines on lower wing either side of the cabin and one inverted 120 hp de Havilland Gipsy III engine in centre of upper wing


Span:55 ft
Length:39 ft 8 in
Height:14 ft 3 in
Wing Area:641 sq ft
Empty weight:3,440 lb
Loaded weight:5,600 lb
Max Speed:108 mph at sea level
Initial Rate of Climb:520 ft/min
Absolute Ceiling:13,000 ft
Range:340 miles