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Ford Trimotor

United States (1926)

Detailing the development and operational history of the Ford Trimotor Transport Aircraft / Passenger Airliner.

 Entry last updated on 3/9/2018; Authored by Staff Writer; Content ©

  Ford Trimotor  
Picture of Ford Trimotor Transport Aircraft / Passenger Airliner

Nearly 200 of the Ford Trimotor transport aircraft were produced from the middle of the 1920s on - some eighteen still fly today.

For a time in aviation history the "Tri-motor" aircraft proved popular for aviation enthusiasts, casual observers and passengers like. There were several major contributions to this aircraft class including Fokker's F.VII and Junkers' Ju 52 during the 1920s and 1930s. The Ford Motor Company of the United States, through their acquisition of the Stout Metal Airplane Company in 1925, added their own take on the triple-engine, high-winged concept and this became known simply as the "Ford Trimotor" covering several variants for both military and civilian use.

The Ford Trimotor held roots in work completed by William Stout and Hugo Junkers and originated in the early 1920s through a team financially headed by Henry Ford himself. This period gave rise to the Stout "3-AT" which first-flew in 1926 and encompassed a single three-engined (Curtiss-Wright powerplants) prototype. The design was progressively evolved and relied on corrugated metal skinning (using aluminum alloys) as pioneered by German engineer Hugo Junkers in his various World War 1 and post-war designs. Series introduction of the Ford product was had in 1926 and 199 examples were ultimately built for many air carriers as well as the United States Army Air Corps (USAAC), the United States Navy (USN) and the Royal Canadian Air Force (RCAF). Several legal defeats for Ford kept the Trimotor from being sold in Europe.

As completed (the 4-AT-E model) the aircraft could manage a top speed of over 130 miles per hour and cruised near 105 miles per hour. Range was out to 570 miles and its service ceiling reached 18,600 feet. Rate-of-climb was 920 feet-per-minute.

Production of Trimotors spanned from 1926 until 1933. The original 3-AT prototype had been followed by the 4-AT which served as a pre-series aircraft and carried 3 x wright J-4 Whirlwind air-cooled, radial piston engines of 200 horsepower. it could carry eight passengers along with its two crew. The 4-AT-B was an improved model and fourteen were built to the standard. The 4-AT-C emerged next and carried Pratt & Whitney Wasp radial engines of 400 horsepower each and held space for twelve passengers - though this aircraft was a one-off. The 4-AT-E was based on the 4-AT-B and given several revisions as well as different engines. It carried a crew of three and eleven passengers. The 4-AT-F was based on the 4-AT-E but its changes unknown.

The 5-AT-A was a dimensionally larger offering (wider wingspan) and powered by PW Wasp radial engines of 420 horsepower each. Thirteen passengers could be carried and three were built to the standard. The 5-AT-B was the 5-AT-A with PW Wasp C-1 or SC-1 radials of 420 horsepower fitted (each). It could carry fourteen and forty-one of the type were manufactured. The 5-AT-C was an improved form and carried seventeen while fifty-one were produced. The 5-AT-CS was a seaplane model, only one of its kind built, and fitted with float equipment provided by the Edo Aircraft Corporation.
Picture of the Ford Trimotor Transport Aircraft / Passenger Airliner
Picture of the Ford Trimotor Transport Aircraft / Passenger Airliner

The 5-AT-D introduced use of PW Wasp SC radials of 450 horsepower each and the wings were slightly elevated while overall weight was increased. Twenty of this kid were completed. The 5-AT-DS was another floatplane model and one was built. The 5-AT-E was a revised, proposed, variant which would have seated the wing engines at the leading edges in more conventional fashion.

The 6-AT-A was the 5-AT-A with Wright J-6-9 radial engines of 300 horsepower each. Three were built. The 6-AT-AS was the floatplane model ad only one of this form was completed.

The 7-AT-A was the 6-AT-A with a PW Wasp radial of 420 horsepower installed at the nose. The 8-AT was a one-off model based in the 5-AT-C and fitting just a single engine (in the nose) and mainly used for cargo-hauling. The 9-AT was the 4-AT-B with 3 x PW Wasp radials of 300 horsepower each. The 11-AT was the 4-AT-E with 3 x Packard DR-980 diesel units of 225 horsepower each. The 13-A was the 5-AT-D with a mixed engine arrangement encompassing 1 x Wright Cyclone radial of 575 horsepower in the nose and 2 x Wright J-6-9 Whirlwind engines of 300 horsepower at the wings. The 14-A carried 3 x Hispano-Suiza 18 Sbr engines of 1,000 horsepower each, was a dimensionally larger variant and could carry up to forty passengers.

Civilian operators included Colombia, Canada, Cuba, Czechoslovakia, the Dominican Republic, Mexico, the United States and Venezuela.

Various models were converted to military forms and fielded under various designations. The C-3A was a transport based in the 4-AT-E and the C-4 was the 4-AT-B. The 5-AT-D made up the C-4A and a re-engined version became the C-4B. The USN/USMC knew the Trimotor as the "JR" and included the JR-2 and JR-3 as well as various "RR" forms.

Military operators included Australia, Canada, Colombia, Spain, the United Kingdom and the United States.

Just eighteen Ford Trimotors are known today (2017) with some being airworthy and others having ended up as protected museum showpieces.
Ford 5-AT Trimotor Specifications
National Flag Graphic
United States
Year: 1926
Status: Active, Limited Service
Type: Transport Aircraft / Passenger Airliner
Manufacturer(s): Ford Motor Company (Stout Metal Airplane Division) - USA
Production: 199
Supported Mission Types
Ground Attack
Close-Air Support
Airborne Early Warning
Electronic Warfare
Aerial Tanker
Passenger Industry
VIP Travel
Business Travel
Special Forces
Crew: 2
Length: 50.26 ft (15.32 m)
Width: 77.82 ft (23.72 m)
Height: 12.63 ft (3.85 m)
Empty Weight: 7,848 lb (3,560 kg)
MTOW: 13,492 lb (6,120 kg)

Installed Power
3 x Pratt & Whitney Wasp C 9-cylinder radial piston engines developing 420 horsepower each.

Standard Day Performance
Maximum Speed: 149 mph (240 kph; 130 kts)
Maximum Range: 550 mi (885 km; 478 nm)
Service Ceiling: 18,504 ft (5,640 m; 3.50 mi)
Rate-of-Climb: 1,050 ft/min (320 m/min)


Operators List
Australia; Colombia; Canada; Cuba; Czechoslovakia; Dominican Republic; Mexico; Spain; United Kingdom; United States; Venezuela

Series Model Variants
• Ford Trimotor - Base Series Name
• 3-AT - Single Prototype
• 40AT - Pre-series aircraft; 3 x Wright J-4 engines of 200 horsepower.
• 4-AT-A - Production model; 14 completed.
• 4-AT-B - Improved mode; Wright J-5 engines of 220 horsepower.
• 4-AT-C - Nose-mounted Pratt & Whitney Wasp radial of 400 horsepower.
• 4-AT-D - Various revisions of 4-AT-B model; three completed.
• 4-AT-E - 3 x Wright J-6-9 engines of 300 horsepower; 24 examples.
• 4-AT-F - One-off revised 4-AT-E
• 5-AT-A - Dimensionally larger; 3 x PW Wasp radials of 420 horsepower; seating fro 13; three examples built.
• 5-AT-B - 3 x PW Wasp C-1/SC-1 radials of 420 horsepower; 15 passengers; 41 examples completed.
• 5-AT-C - Improved model; 17 passenger capability; 51 examples completed.
• 5-AT-CS - Seaplane model; single example
• 5-AT-D - 3 x PW Wasp SC radials of 450 horsepower; slightly elevated wing mainplanes; increased overall weight; 20 examples completed.
• 5-AT-DS - Seaplane model; single example
• 5-AT-E - Proposed model with wings sat at leading edges.
• 6-AT-A - 3 x Wright J-6-9 radials of 300 horsepower; three examples completed.
• 6-AT-AS - Seaplane model; single example
• 7-AT-A - 6-AT-A model with PW Wasp radial of 420 horsepower at nose position; single example completed.
• 8-AT - 5-AT-C model with various engines fitted; used as cargo hauler.
• 9-AT - 4-AT-B with 3 x PW Wasp radials of 300 horsepower.
• 11-AT - 4-AT-E model with 3 x Packard DR-980 diesel engines of 225 horsepower.
• 13-A - 5-AT-D model with 2 x Wright J-6-9 radials of 300 horsepower and 1 x Wright Cyclone radial of 575 horsepower; single-example.
• 14-A - Enlarged model with 3 x Hispano-Suiza 18 Sbr engines of 1,000 horsepower; 40 passenger capability.
• XB-906 - One-off model modified as military bomber form.
• XC-3 - USAAC prototype of 4-AT-A
• C-3 - XC-3 redesignated
• C-3A - 4-AT-E model used as military transport; 3 x Wright R-790-3 engines of 235 horsepower.
• C-4 - 4-AT-B model for USAAC
• C-4A - USAAC military transport
• C-4B - C-4A with 3 x R-1340-7 engines of 450 horsepower each.
• C-9 - C-3A models redesignated and fitting Wright R-975-1 radials of 300 horsepower.
• XJR-1 - 4-AT-A model for USN trials
• JR-2 - USMC transport
• JR-3 - USN/USMC transport; 3 x Wright J-6-9 radials.
• RR-1 - XJR-1 prototype redesignated
• RR-2 - JR-2 redesignated
• RR-3 - JR-3 redesignated
• RR-4 - Single 5-AT-C model
• RR-6 - A pair of 4-AT-D models for USN/USMC service.

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