The Dornier Do X — The Biggest Plane In Europe Of 1920-30s.

The Dornier Do X was the largest, heaviest, and most powerful flying boat in the world when it was produced by the Dornier company of Germany in 1929.

Germany was forbidden during that time to have an air force or making certain types of aircrafts after signing the Treaty of Versailles. In order to comply with the treaty, the German Transport Ministry funded the construction of the Do X and built it in a plant in Altenrhein, Switzerland.

The largest aircraft of its day, the Dornier DO-X was a flying boat powered by no less than 12 engines arranged in tandem atop its huge wings.

Designed by Dr. Claude Dornier, the massive flying boat was equipped to carry passengers in the utmost comfort and luxury. Within its spacious hull were three decks containing sleeping quarters, a bar, writing rooms, bathrooms, a kitchen and a dining room salon nearly 18m long. Built in Germany in 1929, the DO-X made history that year by carrying 169 passengers into the air, then a record number, for a one-hour flight.

The designed capacity, although, was to carry 66 passengers on long distance flights and 100 passengers on short distance flights.

Two years later world attention was focused on the giant aircraft when it took off from Lake Constance, Germany bound for New York City via Amsterdam, Holland; Lisbon, Portugal; Rio de Janeiro, Brazil and Miami, Florida. This ambitious flight soon revealed some of the plane’s shortcomings, among them its excessive fuel consumption. Fully fueled for the flight, the plane lumbered into the air with a takeoff weight of 55 tons.

Pilot's Cabin of Dornier DO-X.
The Capitan and Navigator.

In fact, the plane was so heavy that, even though it was designed to cruise at an altitude of 3000m, it completed much of the crossing service, just above the ocean’s surface.

The flight was billed as a prelude to regular transatlantic passenger service, but it proved to be trouble-plagued and slow. Almost ten months elapsed before the DO-X landed in New York harbor, and although it completed three other crossings, it was clear that the huge craft could not provide efficient passenger service between Europe and the United States.

Interestingly, the builders of the colossal aircraft had chosen the letter X as its designation to indicate that the plane was an unknown quantity. In fact, it was actually ahead of its time, for the technology of the 1920s was not sufficiently advanced for a flying boat as large as the DO-X. For example, the plane’s air-cooled engines tended to overheat and had to be replaced by water-cooled American-built engines.

While the type was popular with the public, a lack of commercial interest and a number of non-fatal accidents prevented more than three examples from being built.

Passenger cabin of the Dornier Do-X flying boat, showing some of the 169 persons on board for the world record flight, Oct.21, 1929.

The Flugschiff (flying ship), as it was called, was launched for its first test flight on 12 July 1929, with a crew of 14. In order to satisfy skeptics, on its 70th test flight on 21 October there were 169 souls on board; 150 passengers (mostly production workers and their families, and a few journalists), 10 aircrew and 9 “stowaways”, who did not hold tickets. The flight set a new world record for the number of persons carried on a single flight, a record that was not broken for 20 years. After a takeoff run of 50 seconds the Do X slowly climbed to an altitude of only 200 m.

As a result of the ship’s size, passengers were asked to crowd together on one side or the other to help make turns. It flew for 40 minutes before finally landing on Lake Constance.

Dornier Do-X flight to New York on November 5, 1930.

Between the time of its record-setting flight in October 1929, with 169 persons aboard , and its maiden transatlantic flight to New York on November 5, 1930, Germany’s giant Dornier Do-X flying boat was sumptuously furnished for the comfort of its well-heeled passengers.

Lounge area of the passenger cabin.

The the interior of the dining area was carpeted with with Persian rugs, decorated bulkheads, and plush upholstered armchairs.

There is almost nothing to suggest that this is the interior of an airplane, and the company’s directors probably would have been quite happy with this verdict.

Dornier Do-X dining area.

Although one might expect the dining room to be relatively spacious, the passenger areas were almost identical, being divided into small “living room” compartments with space for two bench seats on each side of the central aisle. The plane was actually designed to carry 40 passengers, but it could safely accommodate up to 100.

Dornier Do-X Onboatd Bar.

By today’s sardine-can travel standards, the use of interior space on the Do-X seems incredibly extravagant and any modern equivalents are well beyond the average person’s budget.

Flying over New York.

To introduce the airliner to the potential United States market the Do X took off from Friedrichshafen, Germany on 3 November 1930, under the command of Friedrich Christiansen for a transatlantic test flight to New York. The route took the Do X to the Netherlands, England, France, Spain, and Portugal.

One of the Dornier Do-X was sold to Italy.

The journey was interrupted at Lisbon on 29 November, when a tarpaulin made contact with a hot exhaust pipe and started a fire that consumed most of the port side wing. After sitting in Lisbon harbor for six weeks while new parts were fabricated and the damage repaired, the flying boat continued (with several further mishaps and delays) along the Western coast of Africa and by 5 June 1931 had reached the Capverdian Islands, from which it crossed the ocean to Natal in Brazil, where the crew were greeted as heroes by the local German émigré communities.

The flight continued north to the United States, finally reaching New York on 27 August 1931, almost nine months after departing Friedrichshafen. The Do X and crew spent the next nine months there as its engines were overhauled, and thousands of sightseers made the trip to Glenn Curtiss Airport (now LaGuardia Airport) to tour the leviathan of the air. The economic effects of the Great Depression dashed Dornier’s marketing plans for the Do X, however, and it departed from New York on May 21, 1932 via Newfoundland and the Azores to Müggelsee, Berlin where it arrived on 24 May and was met by a cheering crowd of 200,000.

Dornier Do-X in Berin.

Germany’s original Do X was turned over to Deutsche Luft Hansa, the national airline at that time, after the financially strapped Dornier Company could no longer operate it. After a successful 1932 tour of German coastal cities, Luft Hansa planned a Do X flight to Vienna, Budapest, and Istanbul for 1933. The voyage ended after nine days when the flying boat’s tail section tore off during a botched, over-steep landing on a reservoir lake near the city of Passau. While the fiasco was successfully covered up and the Do X was repaired, it was then flown to Berlin, where it became the centerpiece of Germany’s new aviation museum Deutsche Luftfahrt-Sammlung at Lehrter Bahnhof, opened in 1936.

The Do X remained an exhibit until it was destroyed in an RAF air raid during World War II on the night of 23–24 November 1943, by 383 aircraft — 365 Lancasters, 10 Halifaxes, and 8 Mosquitos.