Feb 17 2021 - Feb 17 2021

Ford Tri-Motor


Pan Am's Latin American Workhorse

Although the Ford Tri-Motors of such airlines as T. A.T. or Maddux are better known among aviation historians, more Fords flew in the colors of Pan American than for any other airline; with the possible exception of TACA, the Central American carrier which bought up every used Ford it could find when other airlines had moved on to modern airliners. Most of Pan Am's Fords were flown by its subsidiaries or associates in Latin America, and most of them were the so-called heavy-duty models, with Pratt & Whitney Wasp engines. These were various series of the 5-AT, although in 1933 Pan Am acquired some of the Whirlwind-powered 4-ATs for operations in Cuba.

The Ford Tri-Motor first went into service in the United States on 2 August 1926. Pan American chose it for its mainline routes in Latin America in 1928. Charles Lindbergh piloted the inaugural flight under C.M.A.s colors, from Brownsville to Mexico City on 10 March 1929. Unfortunately the delivery of the mail on this occasion was delayed, as it was left, undiscovered for three weeks, in the luggage compartment situated in the thick wing. Access was by a special hand-operated cranking tool, and the local ground staff did not know of its existence until later.

The first PANAGRA Fords were assembled at Guayaquil in August 1929 and started work along the South American west coast to Buenos Aires in October, flying through to Montevideo in November. Throughout its faithful service with the Pan American organization, it was subjected to severe punishment, not only by the terrain but also by the stringent demands made on its load-carrying capabilities, which sometimes entailed cutting large holes in the fuselage to permit awkward-sized cargoes. The Fords had their fair share of the accidents characteristic of the period, but happily a large number of them carried the newspaper report: "no casualties:" a tribute to their rugged construction.

The Ford Tri-Motor's first service to Pan American preceded its deployment over the route network. On 21 November 1928, Mrs. Calvin Coolidge was supposed to have christened a Fokker Trimotor, but this had been damaged the day before. Juan Trippe promptly leased a Ford from his friends in Colonial Air Transport as a substitute. Although reported in the press, there is no record that Pan American's image suffered thereby.

Development of a Classic Transport Airplane: A "Stout" Effort

Almost certainly deriving inspiration from the German Junkers metal airplane method of construction, William B. Stout, of the Stout Metal Airplane Company, produced a small three-seat airplane in 1923. Powered by a 90 horsepower OX-5 engine, the Stout 1-AS "Air Sedan" made its first flight on 17 February from Selfridge Field, Detroit, and was successful enough to encourage Stout further.

This design was considerably modified to produce a transport airplane. The result was the Stout 2-AT, whose 400 hp Liberty engine permitted a fuselage big enough to hold eight people. At first called the "Air Pullman"' this was changed to "Air Transport:' the abbreviation for which remained throughout the subsequent series of aircraft derived from it. Much of the design work was done by George Prudden, and the metal aircraft began to attract attention after its first flight in 1924.

Ford Takes Over

Edsel Ford took a lively interest in Stout's activity and their two companies began to cooperate. The Ford company quickly built an airport at Dearborn, near Detroit, to prepare for series production of aircraft. Opened on 15 October 1924, the Ford airport was ahead of its time, boasting two concrete runways, measuring 3400 feet and 3700 feet, probably the first of their kind in the world. The Ford Motor Company established its own private airline, which started service between Detroit and Chicago with the Stout 2-AT Maiden Dearborn, on 13 April 1925.

On 31 July Ford purchased the Stout Metal Airplane Company. George Prudden left and Stout himself started an airline with three of the remaining 2-ATs in September. Eleven of the Stout transports had been built, of which five served the Ford airline, with four going to Florida Airways, the company which had been started by Eddie Rickenbacker, and which was one of the original aspirants for a foreign air mail contract to the Caribbean and beyond.

A Tri-Motor is Born

In 1925, the lightweight Wright Whirlwind radial engine became available and Stout and his team modified the Liberty-powered 2-AT design into the first tri-motor, the 3-AT. Cumbersome in appearance, by the standards of later developments, it made a few test flights, but was destroyed at Dearborn on 17 January 1926.

Inspired, however, by the apparent soundness of the three-engined idea, and under the direction of the Chief Engineer of the Ford Motor Company, William B. Mayo, a new factory and a new airplane were quickly forthcoming. The first Ford 4-AT flew on 11 June 1926. Under the general design direction of Thomas Towle, with assistance by John Lee, Otto Koppen, and H.A. Hicks, the prototype appears to have been hand built. At the insistence of the test pilot, Major "Shorty" Shroeder, it had an open cockpit, but this was soon modified.

Ford Tri-Motor at Brownsville, Texas c. 1930.
Thus began the production of one of the most important commercial airplanes in the history of air transport. Although there were quite a few variants, two basic series emerged: the 4-AT, with Wright Whirlwind engines, suitable for most domestic uses, and the 5-AT, equipped with the 420 horsepower Pratt & Whitney Wasp engines, for heavy duty work such as in South America. The last Ford Tri-Motor came off the line in September 1932, and at least three are still in flying condition today.
  • Feb 17 2021 - Feb 17 2021

  • (1926-1932)

  • Early Planes

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Adults (13-61): $16
Children (2-12): $14
Seniors (62+): $14

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