On the occasion of the 30th anniversary of the first Liechtenstein airmail stamps, a special helicopter flight was made from Vaduz to Zurich (Kloten) on 28 May 1960. This postcard was one of 11,816 covers sent as domestic mail either to Liechtenstein or Switzerland (4,971 covers went abroad) via this service.
Since mail from Liechtenstein is considered domestic mail, this card was franked with SFr 1,0 postage due. A postal stationery item (10 centimes) and two stamps issued on 7 April 1960 were used for this, which belonged to a set commemorating the first airmail stamp issue of 12 August 1930: the 40 centime stamp with the long-range jet commercial aircraft Boeing 707 and the 50 centime stamp with the long-range jet commercial aircraft Convair 600. After the flight, the items for Liechtenstein and Switzerland were stamped with the airmail date stamp (without the hour number) on the front by the Zurich I letter post office and then forwarded to their destination by ordinary mail. Items to foreign countries were not stamped in Zurich and were forwarded by land and sea.
By the way: the 30-centime stamp of the 1960 commemorative series shows a helicopter and the 75-centime stamp again a long-range jet airliner, the Douglas DC-8.
Quelle: Ring der Liechtensteinsammler e.V. – Ringmitteilungen 1994