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SilberIgel
06-03-2007, 09:10 PM
It was bound to happen.... an accident coaxed on by perhaps a less than careful post accident inspection !

About 2 weeks ago my pristine J3 slipped its moorings and ended up on the garage floor. No serious damage.... broken horizontal elevator, dented rudder and a couple of 'dings' on the starboard wing's LE. All fixable. I patched it up good enough to fly and took the Cubbie out to fly today.

I had carefully examined the plane prior to bringing her to the field. I topped off the batteries, double checked their position for CG, and ran an extensive ground test of the controls (near and far). I waited until some of the guys cleared the field. I batteried up and taxied out. Again, I "wiped" the controls several times to be sure all was well. It looked good so I started the take off roll. It got squirrly so I aborted, back taxied (I probably hit a small rut) and started off again. She got right up to speed and I eased the stick back and as it got off the ground about 10' it quickly became uncontrollable. It nosed up and rolled right still climbing; it did a 360 roll and spilled over on her back while still rolling now about 15' off the ground. I cut the power, reversed the controls and managed to ground it inverted power off heading away from me.

The only damage was to the cowl... crushed in but repairable. My lucky day!!!! I did the 'walk of shame' and put it back on the bench. With no other visable damage, I decided to check it all out and try again. I ran several control checks and all looked fine. I put it on the ground and taxied out to the runway center and turned into the wind. I did one more 'wipe' of all the flight controls.... looked good... NO WAIT!!!!!!! BAD!!! BAD!!! BAD!!!! the port elevator was twitchy. It didn't move with the starboard one. It delayed, then would snap up or down sort of independently of the other. DANG!!!!!

Cutting to the chase..... I think the initial fall two weeks ago must have unlimbered the port elevator clevis from the control arm. In all my operational checks it operated perfectly. I never gave the connections more than a cursory look. Needless to say, the clevis was now un-hitched from the arm and it would sort of push the flappy part up and down with a schitzoid elevon effect.

Sooooo, the teaching point here is to check every thing after a crash.... in DETAIL!!!! Trust nothing!!!! unless you have put your paw and a Mark I, Mod I eyeball on the thing.

I can't believe how lucky I was!!!! I snapped the clevis back together making a mental note to get around to putting some keepers on them. I flew the Cubbie right after that and is was perfect!!!! The icing on the cake was the greazzer landing in front of about a third of the R/C club. I mean that thing just whistled in and settled on the ground dropping its tail gently to the ground. I smartly, U turned and backtaxied the runway in a series of shallow 'S-turns' like a full scale ... taking a 'bow' in front of the audience so to speak!!

Slow Go
06-03-2007, 10:32 PM
My 2 cents, is that mine can run funny as well. What I have found is that they are very sensitive to crosswind on take off. They will do a circle skid very easy. I started checking for wind direction and making sure it's nose is in to the wind. Since then those problems have gone away. They have little problem landing in a cross wind, with a smidge of speed.

SilberIgel
06-03-2007, 10:35 PM
That's all true, Slow-go. Clearly, this was an oversight on my part. Despite checking the controls....many times.... it was apparent that she's not going to fly right with a control rod disconnected.