the Ford Tri Motor

The aircraft Ford designed was the result of a clever, but sneaky, way that Ford and his son Edsel came up with to see the workings of all the all major aircraft manufacturers in 1925

They promoted the Ford Reliability Air Tour, from 1925 to 1931, and used the opportunity to have his engineers take measurements and design data on all the aircrafts assembled for the competition to come up with what would ultimately become the Ford Tri-Motor.

https://www.thehelmsandusky.com/features/fordtrimotor.aspx

https://www.restoretheford.org/