This airmail cover went from Lausanne to Bern, a distance of less than 90 km.

From Bern the cover went to final destination of Birsfelden.
Birsfelden is a suburb of Basel.

This cover was sent from the VIIth Comptoir Suisse, a trade fair held in Lausanne.
Today, September 26, 2004, is the last day of the 2004 Comptoir Suisse.

The cover received a Lausanne Comptoir Suisse CDS 'in the clear.'
There is also a boxed killer on the stamps which notes the trade fair.
The killer has the date, 26.IX.26, at the top left.
The top wing of the biplane reads POSTE AÉRIENNE and the bottom wing has LAUSANNE BERN.*

The cover has a typed request for service via Flugpost:  Lausanne - Bern.
There is also a nice bright blue trilingual airmail etiquette.

There is a Flugpost | Lausanne-Bern CDS on the reverse.

The cover is franked with one the attractive art deco 1925 15 c.
brown red and apple green airmails (Scott C3) and a 1924 5c
gray violet on buff granite paper Tell's son definitive  (Scott 159).

*Thanks to Greg Ioannou for deciphering the top wing's text and finding the date.
Greg also found this excellent example of a similar cover on which the cancel is readable.

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