The Bullfinch was a parasol-winged single-seat fighter which strangely was designed in such a way by Frank Barnwell that it could be changed into a two-seat sesquiplane reconnaissance fighter with a stretched fuselage and a bottom wing nailed on. It was an early application of the Jupiter engine, which Bristol took over from Cosmos Engineering. The third and last Bullfinch I monoplane was converted to the sole Bullfinch II biplane and first flew as such on 17 March 1924.

The photo appears to show trimotor G-EBIX prior to its loan to Imperial Airways which named it City of Washington. In 1929 , G-EBIX was converted from a trimotor to a twin W8g. In this configuration it crashed at Neufchatel, near Boulogne on October 30, 1930. Photo from: Imperial War Museums

One of three D.XIs delivered to the US Army Air Service, probably seen at McCook Field. Photo from: US Air Force

Photo from: Denver City Library Digital Collection

An early photo of Tempelhof. Paid for by Junkers and Deutscher Aero Lloyd, two hangars and a terminal building were erected from June 1923. The terminal is still incomplete here but the familiar radio masts are already standing. The Junkers Works Air Traffic Department was not an airline but a support organisation for the airlines affiliated with Junkers. The Junkers airline took off in August 1925. The Junkers A40 on the left, D-440, carried out a nocturnal Berlin - Stockholm mail flight in August 1924. The other aircraft are F13s, including D-290 and D-313. Photo from: ETH-Bibliothek Zürich

G-EBFO was converted to a D.H. 50J with a Bristol Jupiter engine and used for long-distance flights by Alan Cobham, often on floats. The engine in the photo is an Armstrong Siddeley Puma as fitted when built.

The caption to this photo says the aircraft was from HMAS Geranium, a survey ship. The location is unclear, with the suggestion it may be on Pittwater on Sydney's northern outskirts. However it is far more likely to be Sydney Harbour and the headland in the background may be Middle Head. Geranium and A10-2 were brought together on Sydney Harbour after it was decided aircraft would be useful for survey work ahead of the mapping of reefs in Northern Australia. Photo from: City of Sydney Library

How about having the Soviet Union, the United States and Germany in your order book! Fokker achieved this with the D.XI fighter, although Germany's order was cancelled and taken up by Romania. The USAAS received three D.XIs with the PW-7 designation and Curtiss D-12 engines. 68580 had standard plywood wing skinning and V-type struts, but 68581 and 68582 had fabric wing skinning and N-type struts. Note bombs and McCook Field code P-327 on rudder. Photo from: San Diego Air & Space Museum

The Scarab was a military flying boat, based on the Supermarine Sea Eagle, but outfitted with a pusher engine. 12 frames were built for the Spanish Navy for bomber/reconnaissance purposes. They were fitted with a .303 Lewis gun and had a bomb load of 1000lb/545kg. The first Scarab made its first flight in May 1924. That summer, 11 frames were delivered to Spain by ship, but 7 of them were damaged during the voyage. the remaining 4 were sent to Morocco to serve in the campaign. against Abd-el Krim. Photo from The Royal Aeronautical Society (National Aerospace Library)

Used as an aerial ambulance. Avro photo. Photo from: Civil Aviation Historical Society, Melbourne, Australia

Built at Mascot, Sydney. Flown from a nearby cow paddock that is today's Sydney International Airport. G-AUDR registered in 1922, the year AAEC went bust. It had been formed three years earlier to make 504Ks. -UDR initially fitted with a Sunbeam Dyak engine but in the photo has a more powerful Curtiss K6. The distinctive 504 rudder has been replaced with a fin and rudder resembling that of an Avro Avian. Avro wrecked in a gale at Moora Valley c1926. Photo from: State Library of Queensland