K5911 has a dorsal fuel tank. Photo from: Imperial War Museums

Early Wellesleys K7715, K7716, K7717 and K7718 equipped the B flight of No 7 Sqn, which was separated off to start No 76 Sqn at Finningley on 12 April 1937. Photo taken there that month - a group portrait of the new squadron exists with the same aircraft and the same treeline in the background. By 18 October 1938, K7716 was assigned to No 148 Sqn at RAF Stradishall. It collided head-on in mid-air with K7714 that day over Great Dunmow, Essex, and all six crew were killed.

One of two Dragon Rapides delivered to Aero O/Y for experimental domestic services. Impressed by the Finnish air force for medical and transport flights in 1939. Sold to Denmark in 1955 and to Germany in 1956 as D-IGEL. Burnt in 1972. Photo by: Urho Aarre Saarinen / Finnish Heritage Agency

The two Lithuanian Dragon Rapides. Data for the nearest aircraft - the other is clearly marked 702 here. It seems 701 wore its serial on the starboard side only, and 702 on the port side only. Photo assumed taken at Hatfield. Photo from: British Aerospace

Reputed to be the first passenger flight between Manila and Hong Kong. Pan American initially used S-42s for the final two stages of its trans-Pacific passenger services. Martin M-130s flew the stages from San Francisco to Manila. Hong Kong's water airport was a jetty at Kai Tak aerodrome. NC16724, later renamed Samoan Clipper, exploded on January 11, 1938 while attempting to dump fuel so it could return to Samoa. Killed was famed Pan Am pilot Ed Musick. Photo from: National Library of Australia

Believed to be 701. It seems 701 wore its serial on the starboard side only, and 702 on the port side only. DH photo. Photo from: Civil Aviation Historical Society, Melbourne, Australia