Potez 29 five-passenger airline of the ambitious French company CIDNA. Note 'Vi-Pr' on the tail, presumably meaning that it worked the Vienna - Prague route. Photo from: ETH-Bibliothek Zürich

Proving flight to Teheran with Maurice Noguès. While the Blériot-SPAD S.33 was upgraded to S.46 and S.66 standard, the S.56 was a new-built type with a Jupiter engine. A painter is still busy applying the airline title above the reg. The row of hangars at Le Bourget is much the same today - many of our uploaders have been poking around for photo opportunities between them. Photo from: Bibliothèque nationale de France - Gallica

Smart biplane airliner of CIDNA. The company operated Vienna - Warsaw as a branch of its Paris - Istanbul route. Photo from: Narodowe Archiwum Cyfrowe

F-AHAF first flew as a three-engined F.120 (F.4X) Jabiru on 21 February 1925 - see other photo. Supposedly it crashed in four-engined F.121 (F.3X) form only three months later in Romania. According to more credible information it flew until withdrawn in October 1931. Veteran pilot Colonel Gilbert Casse died on 31 October 1925 and in all likelihood the aircraft was named after his passing away.

The spectacularly ugly three-engined F.120 Jabiru was originally designated Farman F.4X. Confusingly, it was preceded by the more successful four-engined F.3X or F.121. The family also included a single-engined F.120 bomber, and the twin-engined F.122, F.123 and F.124. Photo from: ETH-Bibliothek Zürich

Apparently a display of CIDNA aircraft at Zürich - Dübendorf. It seems that the French airline used to fly Strasbourg - Prague non-stop, but that the Germans started to confiscate aircraft that needed to land and that a detour via Switzerland was made for some time to reach Eastern Europe. Note the enormous wing chord of the three-engined Jabiru. Centre and right, two Caudron C.81s, F-AGFS and F-AGGF; left, two Blériot-SPAD aircraft; and top, two Farman F.70s, F-AGGG and F-AGGH. The latter were sold to Poland and were delivered through Dübendorf in May 1925. Photo from: ETH-Bibliothek Zürich.

The Blériot-SPAD S.33 was an elegant biplane airliner seating four passengers in the forward cabin and sometimes a fifth next to the pilot. The improved S.46 had the Salmson 9 radial replaced by a more powerful Lorraine 12D inline engine. CFRNA acquired a large fleet of 38 S.46s. From 1925, its successor CIDNA had the surviving 34 aircraft refined to S.66 standard. Photo from: ETH-Bibliothek Zürich

Photo taken by a Swiss geologist, apparently at Dübendorf. This trimotor was taken on charge in November 1924 by CIDNA's predecessor company, CFRNA - Compagnie Franco-Roumaine de Navigation Aérienne. It crashed near Budapest on 24 May 1928. Photo by: Paul-Louis Mercanton / ETH-Bibliothek Zürich