MIAMI – Today in Aviation, G-ABPI, the prototype of the Armstrong Whitworth AW.15, performed its maiden flight in 1932; the type was given the name Atalanta, which was eventually transferred to the entire class.

The Armstrong Whitworth AW.15 Atalanta was a four-engine airliner developed and built by Sir W.G. Armstrong Whitworth Aircraft Limited in Coventry, UK.

The Atalanta was designed expressly for British carrier Imperial Airways, which needed a new four-engined airliner to cover its African operations. Because of its low drag attributes, a monoplane configuration was chosen for the new type, resulting in a significantly different configuration than the previous Armstrong Whitworth Argosy aircraft.

After its maiden flights, flying tests found only minor issues, most of which were quickly fixed, allowing the plane to acquire an airworthiness certificate only three months later. Imperial Airways launched the first commercial service of the type from Croydon to Brussels and Cologne on September 26, 1932.

The Atalanta serviced the airline’s Eastern lines for five years before being displaced; in its later years, the type was flown by a variety of civil and military operators until it was phased out during WWII.

Origins


Imperial Airways released a specification for a four-engined aircraft to operate its African lines, in particular the service between Kisumu, Kenya, and Cape Town, South Africa, in 1930. This request was largely responsible for the AW.15 Atalanta’s origins.

According to aviation author Oliver Tapper, the airline realized that in order to achieve the desired immunity from forced landings due to a single-engine failure in mid-flight, new airliners with four engines, rather than three engines like the existing Armstrong Whitworth Argosy, would be required.

And so, the aircraft designer John Lloyd at Sir W.G. Armstrong Whitworth Aircraft Limited evaluated Imperial Airways specification and swiftly determined that the best way to meet its requirements was to use a monoplane configuration, which was more aerodynamically efficient than a biplane counterpart.

Imperial Airways was so delighted with the company’s concept that they took the rare step of ordering it ‘off the drawing board.’

G-ABPI in the service of Imperial Airways in 1936. Photo: Unknown author – Civil and Military Gazette 1936, Public Domain

Design


Armstrong Whitworth A.W.XV Atalanta 3-view drawing from NACA-AC-167. Image: By NACA Aircraft Circular, Public Domain

The Armstrong Whitworth Atalanta was a streamlined monoplane airliner with high wings. It had a relatively clean square-section fuselage with rounded corners to reduce drag. Steel, plywood, and fabric were used in the aircraft’s composite structure.

To reduce drag, the undercarriage was fixed but partially enclosed within the fuselage and covered by streamlined fairings. Passengers were transported in a pretty quiet and cool cabin with nice adjustable seating.

The Atalanta’s general design was quite advanced for the time; according to Century of Flight, the Atalanta bridged the performance gap between British and American airliners. Atalanta (/ˌætəˈlæntə/; Greek: Ἀταλάντη Atalantē) which means “equal in weight”, is a heroine in Greek mythology.

The aircraft was powered by four supercharged Armstrong Siddeley Serval III ten-cylinder radial engines, each rated at 340 horsepower (250 kW). This engine was a recent development, consisting essentially of two Armstrong Siddeley Mongoose engines connected together.

These engines, which were mounted on the wing’s leading edge, were faired into the wing profile to improve aerodynamic efficiency.

Artemis at Lydda Airport, 1939. Photo: American Colony (Jerusalem). Photo Dept., photographer – This image is available from the United States Library of Congress’s Prints and Photographs division under the digital ID matpc.18301, Public Domain

Operations


Imperial Airways placed an order for eight planes, which were all delivered by 1933. On September 26, 1932, the first service was flown from Croydon Airport to Brussels and ultimately Cologne.

The eight aircraft produced had some of the most beautiful names aircraft can have, all originating in Greek mythology and all starting with the letter A:

  • Atalanta (c/n 740; G-ABPI, renamed Arethusa; later VT-AEF, DG453)
  • Andromeda (c/n 741; G-ABTH)
  • Arethusa (c/n 742; G-ABTI, renamed Atalanta; later DG451)
  • Artemis (c/n 743; G-ABTJ; later DG452)
  • Athena (c/n 744; G-ABTK)
  • Astraea (c/n 784; G-ABTL; later DG450)
  • Amalthea (c/n 785; G-ABTG)
  • Aurora (c/n 786; G-ABTM, later VT-AEG, DG454)

Featured image: Photo taken of the Atalanta by an employee of the British government prior to 1956. Public Domain. Article source: he Illustrated Encyclopedia of Aircraft (Part Work 1982-1985). London: Orbis Publishing, 1985.