Originally Posted by BugDevHeli
The plan is to have a full size version on test, mounted on the homebuilt Bug3 by late summer next year.
Bug, i'm sure you are responsibly going through the cert process but just a bit of advice from a fellow engineer. Since the drawings will have been done for one prototype, i would build two. The second one keep on the ground in a whirl tower, electrically driven so you can run it ~24/7. Continously cycle it through idle/takeoff/hover/climb/flight/extreme_manouvre/descend/auto/land/shutdown, or as much as you can simulate in a whirltower (use a 2nd or 3rd fan if possible for airflow). Keep a computer log if possible about completed cycles, and high speed film of the last 15 mins say (so you can see how any individual fault developed).
Since Bug3 uses proven R22 components, you need to be at least as convinced about reliability of your components as these. Regularly inspect the ground test prototype for cracks, i don't know what techniques exist for composite. I would suggest strain guaging stess hotspots, but don't know if kit exist to get strain data to static receiver. The idea is you can correlate ground accelerated durability test hours to actual flight hours (normally stress PSDF vs freq is compared). If there should be a design defect, you will detect it well before it puts anyone at risk. The flying prototype can then concentrate on performance development to begin with. This will also help the money men gain confidence in your product.
I imagine you have used some FEA code? I use I-deas for my day job, but wouldn't recommend it!
Mart