Fly it all the way to the crash site!
03-28-2019, 03:58 PM
#1
Fly it all the way to the crash site!
Used my old saying to save another one today. YA F-22 owned by a friend. He a good builder and pilot but wanted me to test it as I had one prior. I flew out from SC to TX for the test flight. On t/o it rolled 90 right. I recovered and then it pitched straight up. I had no idea of what was happening. I got it on a downwind and it pitched up and rolled again. It was in the process of an uncontrolled flyaway over the lake. I pulled up and it went down, I rolled and pulled again and this time it climbed. I got it back enuf to get over the runway and saw something sticking out. I put gear down and got it back again
. The entire time it was rolling 45° left and right. On the ground we found both rudders fluttered and stripped servos. The right rudder was being held on by the control rod.
I always tell my jet students to never quit flying...even to the
crash site. If you quit flying it crashes for sure.
. The entire time it was rolling 45° left and right. On the ground we found both rudders fluttered and stripped servos. The right rudder was being held on by the control rod.
I always tell my jet students to never quit flying...even to the
crash site. If you quit flying it crashes for sure.
03-28-2019, 04:08 PM
#2
He’s not the first to have that issue on the yellow. You MUST use good mechanical advantage and good links and rod ends. Also another guy lost his when one of those crappy plastic control horns that come with the kit failed.
You up need a big carbon fiber control horn. Got mine from BVM I think it was for the bobcat. Need to use the inside holes on the servo side.
Good save Tom!
You up need a big carbon fiber control horn. Got mine from BVM I think it was for the bobcat. Need to use the inside holes on the servo side.
Good save Tom!
03-28-2019, 05:44 PM
#5
Used my old saying to save another one today. YA F-22 owned by a friend. He a good builder and pilot but wanted me to test it as I had one prior. I flew out from SC to TX for the test flight. On t/o it rolled 90 right. I recovered and then it pitched straight up. I had no idea of what was happening. I got it on a downwind and it pitched up and rolled again. It was in the process of an uncontrolled flyaway over the lake. I pulled up and it went down, I rolled and pulled again and this time it climbed. I got it back enuf to get over the runway and saw something sticking out. I put gear down and got it back again
. The entire time it was rolling 45° left and right. On the ground we found both rudders fluttered and stripped servos. The right rudder was being held on by the control rod.
I always tell my jet students to never quit flying...even to the
crash site. If you quit flying it crashes for sure.
. The entire time it was rolling 45° left and right. On the ground we found both rudders fluttered and stripped servos. The right rudder was being held on by the control rod.
I always tell my jet students to never quit flying...even to the
crash site. If you quit flying it crashes for sure.
03-29-2019, 11:58 AM
#16
Those GP clevises ALWAYS needs back-up nuts on the threaded end side..........period! I have seen this episode over and over again, having worked in hobby shops for 20+ yrs. The clevis will always rock back and forth an be susceptible to flutter every time...............my opinion............I realize that was just one issue you faced.
04-03-2019, 05:31 AM
#23
Happened to my with my F-35. I hand't realized the servo would take so much load (must be a V tail deal!), and simply CA'd the servo mount in place. I cold not trim roll, but the other rudder was ok...so I landed it normally.
Looks like the trip paid for itself!
David
Looks like the trip paid for itself!
David
04-03-2019, 08:10 AM
#24
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Great save and agree with others on the mech. adv. Given it happened to both sides and as soon as you took off meant there is no margin really in the design. Kind of shocking as hinges/surfaces look solidly mounted. The servos type/torque used here is how much?
Last edited by dbsonic; 04-03-2019 at 08:26 AM.
04-05-2019, 10:04 AM
#25
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You're absolutely right Tom! Fly it till it wont fly no more. I learned this from my motorcycle road racing days. Whenever you think your not going to make the corner..try anyways, you have nothing to lose. Most of the time you will come out ok. But as you say.. if you give up, you will for sure crash..100%