Flying Pancake Program

  Origins and Context

Charles H. Zimmerman developed the Flying Pancake concept from 1933-1937 while working at NACA Langley Field.¹ The design featured a circular wing with propellers at the wingtips to minimize drag and enable extremely short takeoff and landing capabilities.²

  Program Structure

The program consisted of two phases: the wooden V-173 proof-of-concept aircraft and the all-metal XF5U-1 fighter prototype.³ The V-173 first flew on November 23, 1942, powered by two 80-hp Continental A-80 engines,⁴ while the XF5U-1 used more powerful 1,600-hp Pratt & Whitney R-2000-7 engines.

  Legacy

The V-173 completed 131 flight hours across 199 flights, proving the viability of Zimmerman's circular wing concept.⁵ Though the XF5U-1 showed promise with projected speeds of 425 mph, the Navy canceled the program in March 1947 as jet technology superseded propeller-driven aircraft.⁶

  References

1. Vought Heritage, "V-173 Flying Pancake"; NASA, "Charles H. Zimmerman". ↩

2. NASA, "Charles H. Zimmerman". ↩

3. Vought Heritage, "V-173 Flying Pancake"; SAE Technical Paper 470229, "Experiences of an Aircraft Manufacturer with Sandwich Material". ↩

4. Vought Heritage, "The V-173 Aircraft". ↩

5. Vought Heritage, "The V-173 Aircraft". ↩

6. Vought Heritage, "XF5U-1 Flying Pancake"; Vought Heritage, "XF5U-1 Specifications". ↩