Ford Trimotor

The Ford Trimotor (also called the "Tri-Motor", and nicknamed the "Tin Goose") is an American three-engined transport aircraft. Production started in 1925 by the companies of Henry Ford and ended on June 7, 1933, after 199 had been made. It was designed for the civil aviation market, but also saw service with military units.

In the early 1920s, Henry Ford, along with a group of 19 others including his son Edsel, invested in the Stout Metal Airplane Company. Stout, a bold and imaginative salesman, sent a mimeographed form letter to leading manufacturers, blithely asking for $1,000 with the line, "For your one thousand dollars you will get one definite promise: You will never get your money back" to convince them. Stout raised $20,000, including $1,000 each from Edsel and Henry Ford.

In 1925, Ford bought Stout and its aircraft designs. The single-engined Stout monoplane was turned into a trimotor, the Stout 3-AT with three Curtiss-Wright air-cooled radial engines. After a prototype was built and test-flown with poor results, the "4-AT" and "5-AT" emerged.

The Ford Trimotor using all-metal construction was not a revolutionary concept, but it was certainly more advanced than the standard construction techniques of the 1920s. The aircraft resembled the Fokker F.VII Trimotor (except for being all metal which Henry Ford claimed made it "the safest airliner around"). Its fuselage and wings followed a design pioneered by Junkers during World War I with the Junkers J.I and used postwar in a series of airliners starting with the Junkers F.13 low-wing monoplane of 1920 of which a number were exported to the US, the Junkers K 16 high-wing airliner of 1921, and the Junkers G 24 trimotor of 1924. All of these were constructed of aluminum alloy, which was corrugated for added stiffness, although the resulting drag reduced its overall performance. So similar were the designs that Junkers sued and won when Ford attempted to export an aircraft to Europe. In 1930, Ford countersued in Prague, and despite the possibility of anti-German sentiment, was decisively defeated a second time, with the court finding that Ford had infringed upon Junkers' patents.

Although designed primarily for passenger use, the Trimotor could be easily adapted for hauling cargo, since its seats in the fuselage could be removed. To increase cargo capacity, one unusual feature was the provision of "drop-down" cargo holds below the lower inner wing sections of the 5-AT version.

One 4-AT with Wright J-4 200-hp engines was built for the U.S. Army Air Corps as the C-3, and seven with Wright R-790-3 (235 hp) as C-3As. The latter were upgraded to Wright R-975-1 (J6-9) radials at 300 hp and redesignated C-9. Five 5-ATs were built as C-4s or C-4As.

The original (commercial production) 4-AT had three air-cooled Wright radial engines. It carried a crew of three: a pilot, a copilot, and a stewardess, as well as eight or nine passengers . The later 5-AT had more powerful Pratt & Whitney engines. All models had an aluminum corrugated sheet-metal body and wings. Unlike many aircraft of this era, extending through World War II, its control surfaces (ailerons, elevators, and rudders) were not fabric covered, but were also made of corrugated metal. As was common for the time, its rudder and elevators were actuated by metal cables that were strung along the external surface of the aircraft. Engine gauges were also mounted externally, on the engines, to be read by the pilot while looking through the aircraft windshield. Another interesting feature was the use of the hand-operated "Johnny brake."

Like Ford cars and tractors, these Ford aircraft were well designed, relatively inexpensive, and reliable (for the era). The combination of a metal structure and simple systems led to their reputation for ruggedness. Rudimentary service could be accomplished "in the field" with ground crews able to work on engines using scaffolding and platforms. To fly into otherwise-inaccessible sites, the Ford Trimotor could be fitted with skis or floats.