Scare me...

A few years ago we were having dinner at one of those Hibachi places were the pseudo-Japanese cook (in this case he was really Japanese) tosses his knives around entertaining you with faux-danger. Except this guy's knife went flying, but he caught it, and demurely stated, "Scare me..."

I had been setting up Frankenheli's gyro when it became evident that the receiver was browning out and the servos were going nuts as a result*. I pulled the receiver from the CopterX 250 and bound her to Franky to see if that was the problem, and its not (I suspect the new ESC; of course I have no idea where I bought it from...). Anywho, I had to rebind the 250, and since I wasn't going to get to garage hover Franky, I thought I would tune up the 250 and give her a shot, now that I am using dual rates and understand expo better. (The last time I flew her did not go so well...). I also had put one of those Hobby King/Assan mini-MEMS 250 gyros on her and wanted to set that up and flight test her. So I rebound her, and set up her CCPM. I took her out to the garage, where I had to have the door closed due to the high winds outside. This gives me the heebie-jeebies 'cause there is no where to run if things get jiggy. I let her spin up on the ground, checked her tracking (sweetly tight) and then brought her up to a hover. She is a 250, which for heli people means she is exaggeratedly agile and quick in response to control inputs, whether the pilot is or not, and I am not, so that added to the tension. I had her in the center of the garage  in a low hover when I heard a loud POP! and immediately hit Throttle Hold as I saw the blades bouncing off the walls and heli going straight down (suggesting they went at the exact same time). These were brand new never flown fiberglass blades! SCARE ME!

She is undamaged. You can see the blades only damage came from striking the walls and stuff in the garage, and that the roots are cleanly snapped off. The fly-bar is slightly bent as the heli tipped a little when it hit the ground with the rotor momentum still spinning the rotor head.

A close up of the blade roots. I wonder what made them fail the same way at the same time... I was only hovering a little skittishly, though it did required a lot of positive pitch to do so.

Well, after I changed my shorts, I put new CF blades on her and reset up the CCPM, then took her back to the garage for an uneventful though brief proof-of-flight-ready hover. The battery was pretty wiped and I had no charged ones, so I called it a day for the 250. I am glad that once again the mini-MEMS seemed quite stable in controlling the tail (amazing how things work out after I read the manual). 

Man, that truly wigged me out, and my heart is still racing...

* UPDATE (5/3/11, 1545 CST): Turns out it was the tail servo. I bought a knock-off one, a DYS S9065 (a clone of the Futaba S9065). This was the first time it has had power, and I think it was shorted. It got hot and smelled, and responded to inputs variably. When I took it out of the circuit the ESC, receiver and servos work fine. When I put only it in the receiver, everything gets wacky. Bought it on eBay, so its a loss. Ordered a Hitec HSG-5084MG, my favorite tail servo, from Helidirect.