The Gloster Nighthawk aka Gloster Mars VI was a continuing development of the ABC Dragonfly powered Nieuport Nighthawk. Gloster took over the design as the Gloster Mars which evolved into the Sparrowhawk. Either powered by Bristol Jupiter or Armstrong Siddeley Jaguar radials, 29 Nighthawk/Mars VIs converted from Nieuports. Jupiter engine in photo. Three of the 29 were sent to Iraq for testing in 1923. This photo is believed to be one of that trio. Photo from: D.W.F Bonham-Carter DFC (via Jim Cownie)

Blackburn wasn't the most celebrated aircraft manufacturer but the Royal Navy elected to name this type the Blackburn, after the city. It was developed from the Blackburn Dart. The RN wanted a three-seat reconnaissance/gunnery observation plane and to make room for a wireless/navigator's station, the pilot was placed above the Napier Lion engine, giving him a good view but a lot of drag as well. This is the first prototype, converted to Mk II standard with a raised upper wing - the Mk I was much uglier still. Both the Mk I and Mk II did see operational service with the Fleet Air Arm. Photo from: Imperial War Museums

A step between William Stout's Batwing designs and the much better 2-AT. Photo most probably taken at Selfridge Field, where the Air Sedan was tested. Stout was not yet affiliated with Ford then. Photo from Junkers collection which included pictures of aircraft of other manufacturers. Photo from: ETH-Bibliothek Zürich

The first of probably ten C.IIIs delivered to Spain in 1923. The C.III was a Hispano-engined C.I. The aircraft were used as advanced trainers at Los Alcázares, Murcia. A replica of this airframe is in the Museo del Aire, Madrid. Photo from: Fokker-history.com

'The German Casper airliner which arrived first in the prize flight to Gothenburg with captain Leif Lier.' An interesting puzzle in the Dutch national archives. According to the German Wikipedia, Caspar S.I D-292 won a competition in Gothenburg in 1923 (during the ILUG exhibition), and D-292 was sold to Leif Lier from Oslo as N-23. The S.I reconnaissance floatplane was designed by Ernst Heinkel and it eventually became the Heinkel HE 1. It was produced in Sweden for the Swedish air force but also for German undercover training outfits. Photo by: Robert Sennecke / Nationaal Archief (Netherlands)

The Albatros L 58 airliner was built in small numbers. The Deutscher Aero Lloyd succeeded the Deutsche Luft-Reederei, the original airline to use Lufthansa's familiar stylized crane logo, designed in 1918 by pilot and architect Otto Firle. Photo by: Robert Sennecke / National Library of the Netherlands

The second of two Awana transports. Lost to the Vickers Victoria for the RAF order. Armstrong Whitworth photo. Photo from: Civil Aviation Historical Society, Melbourne, Australia.

Demonstrating the blind-flying hood. Photo from: Nederlands Instituut voor Militaire Historie

Built in 1918 for the RAF as E1860. Civilianised in 1922 for Manchester Aviation Co and operated from Alexandra Park airfield until it crashed on 2 August 1924.

The prototype DH-53 Hummingbird ultra light aircraft shortly after completion by DH at their Stag Lane factory and before application of its registration. This aircraft still exists. Obtained from DH 60 years ago.