Swiss airmail covers including Aaurau and Helicopter mail

Описание: Some airmail covers from Switzerland
1938 Aarau philatelic exhibition sheet on cover (Michel block 4)
1944 25 years Swizz airmail (Michel 438)
1948 Helicopter mail (Michel 496 512/513 out of block 13)
1963 used for a flight from Langenbruck to Locarno and back (Michel 1963)
1977 Walter Mittelholzer.. flight from Zurich to Capetown.. Michel 1093 (nice cancellation with a giraffe)