The aircraft is only a few weeks old here if the photo year 1928 is correct. Withdrawn in 1933. Photo from: Narodowe Archiwum Cyfrowe

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

The four-engined F.121 (F.3X) Jabiru came before the three-engined F.120 (F.4X), but apparently F-AHAF first flew as an F.120 (F4X) and was converted to an F.121.

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