www.brantly.info

Here is a link to an accident report regarding a B-2B from March 8, 2003. http://www.ntsb.gov/ntsb/brief.asp?ev_i ... 0318&key=1

Does anyone know any additional info relevant to overall safety?

Well,

The last annual was almost a 1 1/2 years ago, the pilot had no medical, and who knows what else. I forget the intervals, but I think every 100 or 300 hours the tail blades have to be dye-penetrant inspected to insure integrity. This is overlooked on many Brantly's I have seen. There are a lot of rough old machines out there flown from the owner's homes with back tree maintenance performed. That is why if I buy one I make sure it has had a fairly recent 1200 hour by a reputable person or shop and fairly continuous logs since new. Lot's of moving parts and it won't fly without all of them working 100%. One nice thing about the Brantly is the fact that you can usually crash one real hard and walk away if there is no fire.

It appeared that the rivets at the top of the T/R pilon were installed too tight (either when it was rebuilt by an A&P, or from whatever helicopter that part came from), causing a crack over time on the inside of the pilon. On this flight that crack worked its way through the pilon, breaking the top off completely. As the pilot went below ETL, all the force of the T/R thrust was then on the drive shaft, and it also broke off at the top, below the gear box. So the top gear box and entire T/R assembly, including guard, fell off. The pilot then maneuvered away from a tied-down Cessna and when he attempted to get it on the ground, it rolled on its left side. The crack could not have been found without a mirror looking down inside the top of the T/R pilon at those top two rows of rivets. The T/R unit itself (blades, gear box, etc.) did not fail and had no impact on the cause of the accident. The top of the pilon broke causing the vertical T/R shaft to then break and the unit departed the aircraft (i.e., fell off!).

Good info!