DH.86 Danae in Hangar 1 at Cologne's old airport, before conversion to DH.86B standard. G-ADUI Denebola is also seen, with a Focke-Wulf A47 Höhengeier weather aircraft, D-IJTE, on the left. The Heinkel He 70 Blitz on the right is D-USAZ. Photo by: August Kreyenkamp / Rheinisches Bildarchiv Köln

The HP.45 was designated HP.42W by Imperial Airways and initially served on the airline's western (European) routes. Photo taken by an American photographer based in Jerusalem. Two camels can be discerned in the background! Photo from: Library of Congress

Swapped with Qantas at the outbreak of World War II then impressed by the RAAF as A18-10. Destroyed at Broome during a Japanese air raid on March 3, 1942.

Handley Page's prototype of their first passenger airliner, developed from the O/400 bomber. It was written off on 10 July 1923 during a forced landing at Poix in France following engine problems during a flight from Croydon to Le Bourget, when it over-ran the runway and broke it's back. No injuries were sustained by the seven passengers, and the two crew members received "minor injuries". Photographer not known, possibly an Imperial Airways publicity shot?

G-ADUY sank after hitting a submerged object while landing at Batavia (Jakarta). It was shipped back to the UK but was found uneconomical to repair. Scrapped. Photo from: Hudson Fysh Collection/State Library of New South Wales

Security restrictions imposed by Mussolini's regime meant passengers' cameras had to be sealed in a bag while Imperial Airways flights were refuelling at Brindisi. So photos of Brindisi as a Imperial AW port are rare. From contemporary reports passengers were taken ashore by boat because there was no flying boat dock. G-ABFA was the first of three Kents and was lost when it sank at Mirabella Bay, Crete on August 22, 1936. Photo from: Hudson Fysh Collection/State Library of New South Wales

Another AW.15 Atalanta in Africa. Amalthea crashed at Kisumu, Kenya in 1938. Photo from: Koloniales Bildarchiv / Frankfurt University

G-ABTL arriving at Brisbane. It was surveying an air mail route from the UK to Australia to be jointly operated by Imperial and Qantas Empire Airways. QEA believed the Atalanta too big for the section from Singapore to Australia and successfully argued for the DH.86 Express to be used instead. Astraea went on to be impressed into the RAF as DG450 for service in India. Photo from: Hudson Fysh Collection/State Library of New South Wales

Dodoma was a stop on the Imperial Airways route to South Africa. Photo by: Ernst Ackermann / SLUB / Deutsche Fotothek

Built of wood like the Mosquito, the beautiful Albatross was designed to carry mail across the Atlantic or up to 22 passengers on European routes. Due to the outbreak of WWII it was only really used as an airliner during the 1939 summer season. Photo from: ETH-Bibliothek Zürich

Named from Greek mythology, the Atalanta (not Atlanta) was a medium-sized four-engined airliner which carried up to 17 passengers. Not yet named Aurora here, this was the eighth and final example. After brief service with Imperial Airways to Indian Trans-Continental Airways as VT-AEG. Ended up in the Royal Indian Air Force as DG454 and lost in a crash on 6 April 1942. Photo from: ETH-Bibliothek Zürich

Short Calcutta flying boat on the Nile before departure with King Albert of Belgium on board who was travelling to the Congo. Photo from: Library of Congress

The prototype of the HP-42/HP-45. The HP-42 model, called HP-42E by Imperial Airways, was intended for services to India and South Africa and the fleet was based in Cairo. Here Hannibal is seen in Switzerland though, probably during initial testing. Photo from: ETH-Bibliothek Zürich