[1] It remains one of the world's most popular homebuilts with thousands of plans sold and hundreds of examples completed to date.

[citation needed] Based on his previous work with innovative light aircraft, the BD-1 (eventually developed into the American Aviation AA-1 Yankee) and BD-2, Jim Bede designed the BD-4 to be one of the first real "kitplanes" in the world.

[3] The intention was to allow people with little or no fabrication experience to start with a set of comprehensive plans and work up to a bolt-together operation in which complex components were provided from the factory.

In service, it was found that leaks inevitably developed due to problems like improper seals and natural flexing of the wing.

[9] Data from Kitplanes and The Incomplete Guide to Airfoil Usage[10][12]General characteristics Performance Aircraft of comparable role, configuration, and era