Quote:
Originally Posted by Ian Curtis
Have you ever seen an R/C plane with even *close* to the same structural requirements of an FRC chassis? NO!
|
There's always an exception...I have.
Actually, I had a significant part in building one for a project as an undergrad. I had a less significant part in originally designing it, so I can freely concede that it could have been lighter. Nevertheless, it was a 14 ft span, 12 ft long, 80 lb operating empty weight/100 lb loaded weight aircraft, designed for a strange combination of aerial reconnaissance and parachute-based payload delivery.
It was built with a tabbed plywood truss fuselage (basically, a long box, tapered at the ends), with foam-cored, balsa-skinned wings with an aluminum spar.
And although it could have been lighter, one of the practical objectives of overbuilding was to minimize the impact of unusual conditions. It was one aircraft filled with thousands of dollars of stuff, and we were somewhat risk averse. Possible scenarios included payload failures (you wouldn't want a tangled chute to foul the aircraft and break an elevator off), rough landings (mostly avoided), and even being able to recover from skidding off of an iced runway (the taxi tests were harrowing: we didn't have any excursions, but we did manage to bend the landing gear). And yes, since this was the first time scratchbuilding an aircraft for just about everyone, nobody wanted the wings to come off in flight.
Ultimately, it's a convenient counterexample, but I do of course agree that ordinary aircraft don't need to be built to withstand FRC chassis loads.