Sukhoi be gone
07-12-2004, 02:08 PM
#1
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
Sukhoi be gone
After waiting 3 months to get it in the air, my Pheniox Models SU-31 1.20 ARF took to the air. The plane being powered by a 1.60 2s. The plane flew the flight at 1/4 throttle, most touchy plane i have ever flown. About 30 seconds before landing the left aileron started to flutter, followed by the other aileron a few seconds later. The plane lost control and went it. Made my day, maiden flight, maiden crash. The cause? The ailerons pulled loose from the wing. The hinges were glued and pinned.
Heres a few pics of the plane.
Heres a few pics of the plane.
07-12-2004, 06:04 PM
#3
Senior Member
My Feedback: (4)
Join Date: Aug 2002
Location: Tomball,
TX
Posts: 391
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
I'd bet the Hinges pulling out is an effect, not the cause. The aileron linkage hardware looks very lightweight for a 120 size plane with that much control surface. Were any of the servos stripped? What is the servo torque rating? How were the control horns mounted, I see one of them is pulled out? Also, is either servo detached from the mounting hatch?
Richard
Richard
07-12-2004, 06:10 PM
#4
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
Geistware
The wood around most hinges pulled, however, i never took the CA to the hinges
rwlewis
The aileron linkage is fairly good set up for the plane. HOWEVER , the clevisis the give for the ailerons are plastic, i replaced the ones on the tail with metal. The servos in the tail are metal gear, high torque, dual BB, the ailerons were high torque, BB i think. they would have held up to it easy. The servo are still in the mountings tightly, the horns just screwed in. that could have been it, but why didnt the other give, ill have to look closer at it, thanks.
D.R.
The wood around most hinges pulled, however, i never took the CA to the hinges
rwlewis
The aileron linkage is fairly good set up for the plane. HOWEVER , the clevisis the give for the ailerons are plastic, i replaced the ones on the tail with metal. The servos in the tail are metal gear, high torque, dual BB, the ailerons were high torque, BB i think. they would have held up to it easy. The servo are still in the mountings tightly, the horns just screwed in. that could have been it, but why didnt the other give, ill have to look closer at it, thanks.
D.R.
07-12-2004, 06:50 PM
#5
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
heres a pic of the SU right now. I pieced part of the front end toghether. The engine, brand new, has a broken cooling fin. I dont have the proper tools to remove it from the firewall right now, the bolts are bent.
07-12-2004, 07:42 PM
#7
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
Ya, that was another thing that caught my attention, a large aerobatic plane set up as a .40 aerobatic plane. The plane is pretty, but they set it up as if it was a .40 size plane. I was going to replace this plane with a 1.40 size Yak54, but then see that they use wooden dowls to the elevators. Thats asking for trouble.
07-15-2004, 01:27 PM
#10
Join Date: Dec 2002
Location: Kortessem, BELGIUM
Posts: 3,607
Likes: 0
Received 13 Likes
on
11 Posts
RE: Sukhoi be gone
Dago,
How were those control horns mounted to the ailerons?
From what I see in the pics (hard to make out) I think your horns were ripped out. Or at least one, and the other one following in its path like you said.
Unless you built the ailerons yourself, never trust a little self tapping screw that goes into the wood. Selftapping screws into wood are fine, but you need decent wood and surrounding structure inside the aileron.
How were those control horns mounted to the ailerons?
From what I see in the pics (hard to make out) I think your horns were ripped out. Or at least one, and the other one following in its path like you said.
Unless you built the ailerons yourself, never trust a little self tapping screw that goes into the wood. Selftapping screws into wood are fine, but you need decent wood and surrounding structure inside the aileron.
07-15-2004, 02:05 PM
#11
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
Rudeboy,
thats basicly as it looks, the screws didnt take the stress, and maybe thats it, were not to sure. Im not worried about it anymore. Ive pieced the front end back together for templates. The plane was a ARF, so i didnt build the ailerons. The company used some harder wood to build them. The sheeting on the wings is very tough, it took a good beeting and didnt break much, im impressed with the planes construction up to crashing it, lol. I found anothe one i could buy to replace it, its a little cheaper than this one was. I also bought a 30% edge 540 to go along with its smaller russian cousin.
thats basicly as it looks, the screws didnt take the stress, and maybe thats it, were not to sure. Im not worried about it anymore. Ive pieced the front end back together for templates. The plane was a ARF, so i didnt build the ailerons. The company used some harder wood to build them. The sheeting on the wings is very tough, it took a good beeting and didnt break much, im impressed with the planes construction up to crashing it, lol. I found anothe one i could buy to replace it, its a little cheaper than this one was. I also bought a 30% edge 540 to go along with its smaller russian cousin.
07-15-2004, 02:14 PM
#12
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
heres a few more pics of the planes nose, a little crushed, but thats what happens when a plane slams into the ground. I shut the engine down before the plane crashed, no dirt got in the engine.
07-15-2004, 03:52 PM
#14
Thread Starter
My Feedback: (11)
Join Date: Aug 2002
Location: Orange,
TX
Posts: 2,921
Likes: 0
Received 0 Likes
on
0 Posts
RE: Sukhoi be gone
Ya, poor fella never had time to hold on to his head. Thats the things that makes this crash humorous, next to the crash with my brand new agwagon, found the pilot naked, was a brittney spears barbie, hum, makes you wonder, lol.
BTW, she was dressed in the plane, and it covered her up fully.
BTW, she was dressed in the plane, and it covered her up fully.
