AA5BY

Evidently there was not a post crash radio system evaluation to determine if the crash could be attributed to a specific control problem. That leaves speculation and it is unfair to speculate that a brand of servos is faulty because they were in a plane when it crashed.

I'll join the speculation and suggest that based on what has been offered it is likely that the cause was changing out the servo and not because the new servo was bad or the other servos wouldn't work with it, but because different servos have different center positions and it is possible that the new servo wasn't properly centered.

I hate to admit the following but it happened just a few months ago and reveals some of the dumb stuff we do. I have a nice aerobatic plane that got a new more powerful engine. After the change, the plane suffered aileron flutter at which time, the aileron servos were replaced with stronger servos. When doing so, I retrieved the wings from the garage wing rack, changed the servos and used a Turnigy remote servo operator to center them and connected the linkages. It was cold weather and the plane is hangered on the ceiling of the garage above my pickup truck, and I guess I thought that I'd check the centering later rather than go to the trouble to back my truck out and retrieve the plane into the building room at that time.

Well, Y'all all ready can guess what happened. I forgot. And... a month or so later when I flew the plane again, I didn't notice the slight off trim of the ailerons. When breaking ground, it rolled hard and while I got it corrected enough to get the wings level, it was a like riding a bare back in the rodeo. Doubtful of making a circuit and landing it, I cut the throttle and kept the wings as level as possible and let it come down beyond where it could be seen..

After taking ten steps toward retrieving the plane (not knowing its fate yet other than no loud crunching had been heard) it hit me what I'd failed to do. Back on the flight stand, sure enough, the ailerons were not centered. One was off by 1/8 and the other 3/16. I was very fortunate that the only damage was a broken prop. The plane was sitting perfectly level three feet off the ground on top of a black berry thicket facing back at the field and fifteen feet short of a tree line. Not a hole in the covering.

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stevegauth30

Sounds to me like you had a bit of luck on your side. We all do dumb things now and then, regardless of experience. Your right though. We can all sit here and say that we think it was this or that, but in reality, we'll never know. One thing is for sure though, it's never a bad idea to check and recheck , and check again if need be. ESPECIALLY after a crash or major modification. It's good habit to do a pre flight check before EVERY flight. You don't know if a linkage came loose during the last flight or something. It's saved me more than one airframe.

RCPAUL

My Feedback: (1)

Use lots and lots of HITEC servos. No problems. Now, have heard that Spectrum systems have had lots of problems since their introduction.

microdon2

My Feedback: (47)

Two thoughts on this. I just crashed one of my 70" Revolvers (with a DLE 20) last weekend - bad. Was flying fine - first flight - then was coming back up the runway - straight and level - and suddenly lost all aileron control. Plane went pretty much straight into the concreted runway (Floyd Bennet field in Brooklyn) at 2/3 throttle and exploded on impact (bent the crank shaft, cracked the crank case). It looked like I lost radio signial, but my NTSB findings found that I lost an airleron servo - was an older servo with Karbonite gears. The other servo was fine, and I would think that I'd still have some control with one good aileron, but evidently not (too much turbulence from the flapping aileron?). Could you have lost an aileron servo? Possibly damamged \ cracked gear from the previous crash?

I have also had an instance (on my other Rev 70) where I had severe intermittant aileron control while in the air. It was a full one minute struggle to get that plane anywhere close to the ground (almost lost it a few times), but finally - somehow - got it down (and JUST missed cartwheeling). Troubleshooting pointed to a bad Hitek aileron servo (sorry - don't recall the model). If you still have that servo, do you see any intermittant movement while on the ground? btw - I second using the same make \ model of servo for both ailerons \ elevators.

rgburrill

I had a similar problem that luckily was on the ground. It seems the Hitec servos draw a higher operating current and will pull down older batteries. And when the voltage drops the servo wants to go full deflection.

Granpooba

My Feedback: (5)

Have always used either Hitec or Futaba servos and have never mixed them with any other brand names.

Servo problems can sometimes be a real mystery. Took my Cap 232 to the field one day, got everything together and ready for flight, when I discovered that I have no aileron control on either aileron. Thought for sure it either had to be a connection problem or transmitter problem as neither aileron was responding.

Got it home and on the work bench found that I had TWO bad aileron servos. Replaced both servos and the model has been fine ever since, with not a problem one.

Now, what are the odds of TWO servos failing at the same time.

microdon2

My Feedback: (47)

I recently chose a plane to fly the next day and noticed that one of the aileron servos was toothless - no grab at all. Thing is I had just flown that plane the weekend before and had no problems. So when did the servo gear break?? On the last landing? In transit? But I have a wing bag! That one is a mystery.

stevegauth30

Same thing happened to me last season. Kind of. Flew a normal flight, landed uneventfully, fueled up, fired up, checked control deflection, nothing on the elevator. Hmmm, anything can happen at any time.

AA5BY

So true.

Many years ago, my wife bought me an Ultra Stick 120 for my birthday. I commissioned it with a new flight pack or RX and servos and went flying and all seemed well. During the second outing, I did a hammerhead and realized there was no rudder control. The rudder servo had simply stopped. Back on the ground, it was intermittent. I contacted the supplier for a RA number and after they checked out the servo, they called to tell me it checked out fine. I had detailed that it was intermittent in my letter and offered these words. It was intermittent and had it been on the elevator of my new plane, it would be toast. I've marked it in a way I can identify it. If you send it back to me, I'll return it back to you again. Do the right thing and throw it in the trash. They indeed sent me a fresh servo and I've used that same flight system for close to ten years and flown it a lot without any further issues.

Malapp1

Well folks, it seems that this one will go down as unsolved. I took both aileron servos apart today's and both were nice and tidy even after the fatal roll to the ground. I have an idea though, I had the plane set up with one elevator servo that was connected to the two push rods typical for a Great Planes. Although it was impossible to tell after the crash, I wonder if there was some damage from the mid air to the stab that caused one of the push rods to bind. I don't know if ailerons would be enough to counter a elevator that got stuck. It seems to be the only logical alternative answer. I am perplexed but have now moved on to my new Miss Wind pattern plane. Wow, what an airplane. Maiden voyage was beautiful. Thanks everyone for all the good input.

Bozarth

My Feedback: (15)

That is rational...

Kurt

turboromy

Nobody seem to consider a classic stall on take off. Even though it's hard to imagine something like a Revolver would be under powered like those classic trainers, did you have enough airspeed ? Was it the very first flight after wing was fixed / replaced ? CG and/or trim position could have changed. I lost a high wing trainer 2 decades ago just like you described.

jkeze

My Feedback: (36)

How about this for a thought. If you were using a "Y" harness for the two aileron servos and plugged one of the servos into the "Y" harness reversed than I have seen it stop both servos from working. You can connect a Hitec servo plug either way into a Futaba connector

JPMacG

My Feedback: (2)

By chance were you using a Hitek HS-225MG? Mine have all failed. When failed they go to full deflection. They all looked fine inside. Each was an electronic failure with no sign of damage in the gear train.

mattnew

My Feedback: (2)

+1

drac1

My Feedback: (4)

Plugs are designed so they can't be connected the wrong way, but if you did manage to get it connected, the servo would get fried real quick. Long before the plane got airborne. That would definetley stop it working.

HoundDog

My Feedback: (49)

Your first mistake is U used anything with a SPECTRUM label on it . If U or anyone doesn't believe that then
U are beyond help PERIOD Now I'll remove my self from this Forum Thanks for asking it was a pleasure to inform.

drac1

My Feedback: (4)

I'm surprised it took this long for the Spektrum haters to come out.

Not very helpfull or informative

HoundDog

My Feedback: (49)

The truth hurts but seldom Helps those that refuse to listen.
Over and Out
By,Buy,Be

stevegauth30

And here's where a source for useful info turns into a pissing match full of garbage.
Also out. Happy holidays.

flycatch

My Feedback: (26)

Mine failed in the same manner.

AndyKunz

Yes, and I'd certainly put you in your second category.

Or maybe you were right - you might have been talking about the cloners who can't spell our brand name properly. In that case, you would be right to advise people to stay away.

Andy

HunkaJunk

The XG-8 isn't Spektrum, isn't it a JR DMSS system? I wouldn't give this guy a second thought. I once had a complete power loss to a Spektrum receiver at 3/4 throttle resulting in ten minutes of brain melting free flight stress and ending with a horrific crash, to this day there are guys who blame it on the radio system even after the investigation clearly showed the problem was a power loss to the RX, most likely due to a failed switch.

AndyKunz

You are correct, the XG-8 is a DMSS system.

Andy