Anyolmouse wrote:

Some years ago I read that the reason for the requirement that the
majority of work building an experimental/homebuilt aircraft was to
insure the builder "learned" something. That it was to be an educational
experience. Can't find any mention of it today. It used to be they same
for amateur radio as well. We actually built radios, antennas from plans
and schematics and at a later time from Heathkits, etc. Does anyone else
remember the educational requirement and if so when it was no longer
mentioned?

I don't believe there was ever solely a education requirement.

The 51% rule came about because some folks were taking production
airplanes, modifying them, and registering them a Experimental
Amateur-Built. The Nelson N-4 was an example:

http://www.nvva.nl/renekrul/catalogs...elson.n14n.jpg

Basically, it was a cut-down J-3, converted to a shoulder-wing single
seater.

Probably wasn't that big of a deal when it was just an occasional owner,
but I suspect some folks started doing this commercially as a way to
bypass the STC process. Hence the requirement that the majority of the
construction had to be done for "Education or Recreation."

Ron Wanttaja