Frank Stutzman wrote:

Not that I disagree, but would you mind elaborating on your "number of
reasons?"

Scaling to FAI recognized aeromodel limits (11 lb max weight and 10 cc
max engine displacement) was extremely challenging. The TAM effort
was more than four years in development by a small group of dedicated
unpaid volunteers. Team Leader Maynard Hill is 77 years young and,
over a period of almost 40 years, established 23 FAI recognized
aeromodel world records. His pioneering endurance work gave the TAM
project a jump-start. Mr. Hill has done much to further the art of
aeromodeling and this was his crowning achievement (to date). It was
a big deal for him, a big deal for his team, and a big deal for the RC
aeromodel community. The Insitu "Aerosonde" weighed about 29 lb and
was not an FAI recognized aeromodel. Its development was a commercial
effort by engineers under sponsorship from US Office of Naval
Research, L3 Communications, and Boeing.

David O -- http://www.AirplaneZone.com