Dornier Do X Do X1a

Re-engining was the decisive change in the Do X's life. The twelve air-cooled radials gave way to twelve Curtiss V-1570 Conquerors, liquid-cooled V12s of about 450 kW, in the same six tandem nacelles. Only then could the boat hold the altitude an Atlantic attempt demanded, and with the change came the designation Do X1a. The published figures for the type — 40.05 m long, 47.8 m in span, 10.25 m tall, 28,000 kg empty and 49,000 kg at take-off — describe this aircraft in that form.

In November 1930 it left Friedrichshafen under Friedrich Christiansen bound for New York, a demonstration flight meant to open the American market. The route ran through the Netherlands, Britain, France, Spain and Portugal, and at Lisbon a tarpaulin touching a hot exhaust pipe started a fire that consumed most of the left wing. Six weeks sitting in Lisbon harbour while new parts were made, then further breakdowns down the west African coast and another long delay after hull damage in the Canaries.

Stripped of everything expendable and flying with a reduced crew, it crossed the ocean from the Cape Verde islands to Natal in Brazil, worked north through the Caribbean and came down at New York on 27 August 1931, almost ten months out of Friedrichshafen. It stayed nine months with its engines under overhaul while sightseers streamed to Glenn Curtiss Airport — today LaGuardia — to look the giant over.

The Great Depression finished off Dornier's commercial plans. The Do X1a left New York in May 1932 by way of Newfoundland and the Azores and alighted on the Müggelsee in Berlin on the 24th, where two hundred thousand people were waiting. With the company no longer able to afford operating it, the boat passed to Deutsche Luft Hansa, which toured it around the German coastal cities to large crowds.

A cruise to Vienna, Budapest and Istanbul was planned for 1933. It ended after nine days: on an over-steep landing on a reservoir near Passau the tail section tore off. The accident was hushed up, but it closed the aircraft's flying career. After years out of service and several changes of ownership, the Do X1a became the centrepiece of Germany's new aviation collection beside Lehrter Bahnhof in Berlin, where an RAF raid destroyed it in November 1943. Fragments of the tail lost at Passau survive on display at the Dornier museum in Friedrichshafen.