In the 1920s, German inventor Dr. Claude Dornier started the design of a giant "flying boat" to provide luxurious transatlantic air service.    His efforts culminated in the famous aircraft known as the DO-X.   Powered by twelve engines, the aircraft carried 169 people on board during its test flights, a feat unheard of during that era.     On November 5, 1930, the giant aircraft began its first and only transatlantic flight.  Frequent difficulties plagued the aircraft, causing lengthy delays before the next legs of its path could be started.   After crossing the South Atlantic, the plane finally reached Rio de Janerio, Brazil, on June 20, 1931.  The plane left Rio on August 5th, making numerous stops in cities and towns along the Atlantic coast of South America, then island hopped across the Caribbean, finally reaching New York on August 27, 1931.   The return to Germany was delayed, but finally completed in May of 1932.   The Dornier  company had hoped Pan American Airways would place an order for the giant flying boats for service on its new routes, but such was not to be.    The DO-X subsequently flew in Europe, but its last flight occurred on September 5, 1933.

The DO-X flew along the north coast of Haiti, but did not stop in Port au Prince, landing instead in Antilla, Cuba.  However, enterprising aerophilatelists of the era did prepare covers from a few stops along the aircraft's flight route addressed to recipients in Haiti.   Carried by the DO-X, such items are quite scarce and very much sought after by both collectors of Haitian airmail and by DO-X enthusiasts.

Carried from Paramaribo to Port of Spain, Trinidad, with onward transit to Haiti.

Posted August 10th, but not flown until August 19th, 1931.

A registered cover carried from Port of Spain and addressed to Port au Prince.

Posted on August 19th, but not flown until August 20, 1931.

The cover was carried to San Juan, Puerto Rico, with onward transit.