Well a fellow club member totaled his extra or edge today( not sure whitch) He went to fly and had no elevator. Earlier in the day it was fine. Several people tried to find the problem. A change in expo seemed to cure the problem. After several on off, shaking, trying to make the problem come back everything seemed ok, so he decided to fly.

After only a couple of minutes the elevator lost response and the plane came straight down burying the spinner a good 6 to 8 inches in the clay. What few parts that were salvagable were, then the rest was taken to the parking lot, the remainder of the fuel tank was emptied over it and lit on fire.

So what happened? The RX/TX were a JR 6102 not very old. any ideas.

Who knows, but that radio needs to go back to JR. Welcome to the world of model airplanes where s**t happens. You pick up the pieces and go on.

If the elevator was the only control that mis-behaved it was probably (but not guaranteed) a bad elev servo or extension going to it. (Loose connections count in this list).
Was it a single elevator servo plane or dual?

as mentioned there are countless possibilities, I've seen the same thing happen from a chipped gear in the servo from the previous flight, the chip would stick in the grease on the gears and bind at the most inopportune moment and stall the servo. NEVER dismiss something like that when it happens and you can't find a cause, he should have never flown it again till he did a thorough investigation and actually FOUND a cause, this would include sending the complete radio system off for testing if no other positive cause was found.

kc

If there is one phrase that preceedes a crash more often than any other, it's "Well, it'll probably be OK."

Either your plane is working perfectly well and is ready to go, or you shouldn't fly it. No problem is so troublesome or time consuming to fix that it's worse than picking up the smashed pieces of your airplane.

Unfortunately, I offer this advice based on personal experience. I was lucky enough to survive two near-disasters last season. Hopefully I will heed my own advice!

It comes right after "Hey ya'll watch this"

ahhh grass hopper you are very fortunate indeed. you must rearn as you have seen here. that it wirl only get worse in the air.
perhaps a range check at the very reast. better yet done for the day, take her home and reary investagate the probrem.
ahhh grasshopper better to have not frown and go home with prane than to fry and go home with nothing

I can't tell yo uhow many times over the years , I go to the field, set things up. If it's an immediate solution then fine, If you need to think about it, go home. Or as in most cases, I pack up then hang out with the rest of them to help for a few hours.

Better yet, get the next plane out.

it could be the transmitter. One of the big clues is that after changing the expo the servo started to work again. The encoder section of the transmitter might have problems. Send the system back and have it tested out it is cheaper then losing another plane if the problem is with the transmitter

this was a case of poor judgement,when something is amiss you find the cause or do not fly,if for some reason expo on the tx is the suspected cause why even attempt to fly when the tx is not 100%.pack it up and pull out the other plane.send the system in for a check up.remember murphy's law.Any repair will fail at the worst possible time.then there is rule 1 if anything can go wrong it will at the worst possible time.

I had a SIG mayhem and I snagged the elevator on something causing the servo to over-extend. It checked out fine so I flew it and, for short periods of time, I had no elevator. Brought it back and realized I had stripped a portion of one of the gears which would only become a problem periodically. I was lazy about it for a while and flew it knowing that when I lost elevator, I had to cycle the elevator servo a couple of times to get away from that bad area of the gear.

I replaced it a few days later, but it sounds like a similar situation....partially stripped servo.

This is a possibility. Either a switch or potentiometer could have become intermittant and no signal was being sent to the TX encoding section or it didn't recognize a change of condition.
Again, box up the whole thing along with a thorough explaination of what happened and what you observed.

What happened?
He had a problem with his airplane and flew it anyways. Learn from his mistakes.

I was thinking at the time that I wouldn't fly that plane but I'm the new guy.

On a lighter note, I maidened my sky raider II yesterday. Last November I dismantled my Alpha trainer and used the engine and electronics for the raider. The airframe I gave to the club. It flew very well. I didn't preform the take off or landings because of a strong cross wind but I got a lot of stick time.

My progress was hardly noticed by anyone at the field.