Heli-Driver Elite Veteran Location: Arlington, TX
| Well, I'm lucky to have a heli today. yesterday I was on my third flight of my Fury Extreme when all of a sudden I had no control, the heli acted a bit wierd kinda jumped a bit on cyclics and all of a sudden the tail blows out to a blinding pirouette..
I'm grabbing every switch on my 9Z trying to keep the inevitable from happening.. No good... hold didn't work, kill switch, cyclics dead, I got nothing.... the heli is almost level when the problem happened and the piro rate apparently help to keep it level and the pitch was just enough where it didn't drop fast.
It landed over by the control line field and landed on its feet, no blade damage or anything else... the tail boom was pulled from the split front clamp completely, the boom braces were holding the boom to the heli, the drive shaft wasn't damaged nor was the tail section.
The wierd thing is the heli engine died when it landed yet I still had no control and plenty of fuel.
Either the piro rate or the impact (maybe some of each) caused the fuel tank to shift forward and pulled off the fuel line. Otherwise the motor would have been running at idleup speeds.
I guess the 9253 servo just rotated to full stop when the power got turned off by the broken switch causing the piro rate as the motor was still running WFO..
I don't think the tail boom came out first, that could explain the piro rate but doesn't explain the no power issue. So I'm pretty sure the switch was the cause.
I never thought about it but it makes sense that if you lose power in flight and the throttle doesn't drop you'll probably end up with a pirouetting heli because the 9253 is so easy to move with no power I know it couldn't hold the tail rotor without any power.
I inspected the tail boom and there is a slight crack in the boom (maybe an inch long at the front) where it would normally be inside the front clamp so I am replacing the boom. I am totally amazed there was no more damage...
I figured that if that ever happened in flight the heli would probably just fly off and crash, well it was off on it's own but I was very lucky it came down under power pirouetting madly and didn't even tip over...
wierd eh? I'm thinking about adding a spring to the throttle arm and maybe running a dual switch... any thoughts?
Raymond
Predator Gasser SE/231 X 2 Century Helicopters |