Stout 3-AT

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Jan olieslagers (talk | contribs) at 19:58, 13 September 2015 (→‎Development). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Stout 3-AT
Role Commercial airliner and Air Mail freight aircraft
National origin United States
Manufacturer Stout Metal Airplane Division of the Ford Motor Company
Designer William Bushnell Stout, George Prudden, Harold Hicks, Thomas Towle, Otto Koppen, John Lee, and James Smith McDonnell[1]
First flight 1926
Number built 1
Developed from Stout 2-AT

The Stout 3-AT trimotor was the first all-metal trimotor built in America. The poorly performing tri-motor led to an updated design which became the popular Ford Tri-Motor.

Development

As a friend of the Ford family, Richard Evelyn Byrd visited Dearborn in 1925 with the polar exploration aircraft. The all-wood Fokker F.VIIA-3m named the "Josephine Ford" and owned by Henry Ford's son Edsel (and named for Edsel's daughter). The airplane was received as a gift from his father after being placed first in the 1925 Ford Reliability Tour, and lent to Richard E Byrd for his trip to the North Pole, which was sponsored by Ford. This airplane was the prototype for the Fokker F-VIIA-3m and was based at Ford Airfield (now the Ford Test Track in Dearborn, Michigan) and Stout's factory location. Several measurements and photos were taken during its stay.[2] Shortly afterward, the model 3-AT trimotor was produced using an all-metal construction technique. Many similarities exist between the designs that caused controversy. Also, enough differences in technologies were made between the aircraft that the 3-AT can be seen as a unique design, as well.[3]

Design

The 3-AT trimotor had a blunt nose, with its central radial engine mounted close to the nose's bottom, and two wing-mounted outboard, uncowled radial engines, projecting forward of the wings' leading edges at the front of each of a pair of nacelles. The aircraft had a large passenger and cargo compartment with semicircular windows and a large, forward-looking glassed-in window section. The pilot sat in an open cockpit mounted high on the nose of the aircraft. The original design featured three Liberty engines, but they were quickly abandoned due to weight issues.[4]

Operational history

The 3-AT was underpowered for its size. Test pilot Rudy "Shorty" Shroeder could barely circle the field and refused to take off in the plane again. He advised Ford, "Forget the plane." The Model 3-AT trimotor was heavily promoted by Henry Ford as the airplane of the future. Test flights proved otherwise, with the underpowered aircraft barely able to maintain altitude. After witnessing the tests, Henry Ford left outraged. Ford told Mayo, "This plane is a mechanical monstrosity and an aerodynamic absurdity. From now on keep Stout out of the design room."[5] Shortly afterward, Ford reassigned Stout away from engineering.[6]

On January 16, 1926 a fire destroyed the Stout factory and all aircraft in it, including several 2-ATs and the 3-AT prototype.[7] In a 1951 interview, engineer Harold Hicks said that the fire and a fresh start were the best thing that happened to Ford's aviation venture. The 3-AT was impractical with its uncowled engines mounted in the wing roots, disturbing the airflow over the wing, giving it an 80-mph takeoff and landing speed.[8]

Tom Towle was placed in charge of engineering, and hired MIT graduate Otto C. Koppen, John Lee, and James Smith McDonnell (co-founder of what is now McDonnell Douglas). Together, they refined the 3-AT into what is now recognizable as the "Tin Goose", the Ford Trimotor.[9]

Variants

For the Ford 4AT, the basic 3AT design was used, with the main engines placed in underwing, strut-mounted nacelles, and the cockpit moved internally.

Specifications Stout 3-AT Trimotor

Data from Wind and Beyond: A Documentary Journey Into the History of Aerodynamics

General characteristics

  • Crew: 1
  • Powerplant: 3 × Wright Whirlwind J-4 Radial, 200 hp (150 kW) each

Performance

References

  1. ^ National Aeronautics and Space Administration. Wind and Beyond: A Documentary Journey Into the History of Aerodynamics. p. 233.
  2. ^ Peter Pigott. Taming the skies a celebration of Canadian flight.
  3. ^ Tom D. Crouch. Wings a history of aviation from kites to the space age.
  4. ^ Henry M. Holden. The fabulous Ford Tri-Motors.
  5. ^ Michigan history volume 82.
  6. ^ Tom D. Crouch. Wings a history of aviation from kites to the space age.
  7. ^ Sport Aviation: 8. April 1975. {{cite journal}}: Missing or empty |title= (help)
  8. ^ National Aeronautics and Space Administration. The Wind and Beyond: A Documentary Journey Into the History of Aerodynamics.
  9. ^ Douglas J. Ingells. Tin Goose the fabulous Ford trimotor.