Inventor request
The Department of Defence expressed an interest in buying a "flying, floating automobile" from an Austrian inventor in 1966, the State papers show.
The machine, which looked like a large rectangular box with sloping sides, was promoted by its inventor, Helmut Feuerstein. Its merits, he contended were on the basis that it had "no wings, therefore not clumsy outside and large and roomy inside".
It was "practically uncrashable" and was economical to run, the inventor said. It also had a high carrying capacity and "does not require roads, bridges, expensive aerodromes etc", according to files released in the National Archives.
The inventor had made contact with the Irish ambassador in Switzerland and on the request of the Department of Defence, passed on drawings and a photograph of the machine.
However, despite some initial interest, a Department of Defence official later wrote that "while the machine is of interest, it has no practical relevance to this Department at present".