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Stuck flaps problem

humptybump

Well Known Member
I was doing pattern work today and on the fourth landing, when I went to deploy the electric flaps on my RV-8 they did not move. I diverted to an airport with a longer runway and did a no-flaps landing and taxied to park.

With the engine shut down I tested the flaps. There was no noise. I checked the breaker and it was fine. I applied a small amount of down pressure on the flap and tried the switch again and they worked fine.

I am not the builder so here is my question - is there a limit switch that would cause this behavior and if so, is it located at the flap motor under the cover panel at the rear passenger seat? If not then what else might it be?

I plan to open it up this weekend.
 
No limit switch just a common problem.

Search the forum and you'll find directions for opening the motor to clean grease and dust from brush wear. After cleaning, your flaps will be good as new.
 
Every RV is different, but my guess is it's probably not a limit switch. The switch would naturally only prevent actuation of the flap motor in one direction. Otherwise you would never be able to deploy them when retracted or retract them when deployed.

There are a myriad of different flap setups in RVs. Perhaps a little more insight into how yours works would help. (i.e...do you hold down the switch to drop flaps or just tap once)?

My guess? You've got the classic RV flap motor failure. A simple service job can usually fix it up. I've personally never experienced it but others have.

There are a lot of threads on this so some searching on the topic would be the prescription.

Here's a fairly recent thread: http://www.vansairforce.com/community/showthread.php?t=82373&highlight=flap+motor

Edit: Randy beat me to the punch -- what he said!

Hope that helps,
 
Well, there might be a limit switch if you can flip the switch to the "up" position, and when it gets all the way up, the motor turns off...does it do that? There are no limit switches in the motor itself, but many of us add them into the circuit.

However, this is not a new problem by a long run - many folks (including me) have had the problem of an intermittent flap motor - usually because grease migrates out of the gearbox and into the motor. I had to clean mine up at about 300 hours, and just had to do it again at about 1400.

It's really no big deal at all to land an RV-8 with flaps up - you might use 5 - 10% more runway. Flying a cross-country with the flaps stuck DOWN is going to be a real pain. You can sometimes get away with taking off the rear seat side cover and tapping on the motor with a screwdriver handle (or a little hammer). If they are stuck down, this might get them up to allow you to return home. All this takes is a Phillips head screwdriver to get the cover off.

Good luck!

Paul
 
RV 8 Flaps

I have and built an RV8 and haven't had any flap problems. There is no limit switch but Vans has had problem with the electric flap motor. Check the RV service notices on the web page. Van's changed suppliers and the new ones had to much grease in the moter and caused then to short out

Good luck
Dick Johnson
 
To add to Paul's comments, depending how you wired it at the motor, if you disconnect the wires and pull the mounting bolt on the motor end, you can screw the motor and housing down till it stops and have someone help lift the flaps as you reinstall the bolt.
If the other end is easier to remove the bolt, then just screw that end in.

At least it will get you home.................:eek:
 
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Thanks everyone!

I didn't equate my "stuck at the extent" problem with all of the flap motor maintenance threads (although my inner muse must had had some incling since I've read many of hose lately from first to last).

I'll do the maintenance this weekend.
 
I've had enough flap problems with the migrating grease issue to the extent I don't use them (unless necessary) especially on a flight away from home.

Landing without flaps is a non event, flying any distance with extended flaps is a problem - its about like a Piper Cub cross country and takes for ever. :)
 
EZ fix

Just experienced this problem on Sunday. Had to fly 40 miles home with full flaps. No warning, no sound, no nothing, just stuck there. As David, said, took like what seemed forever.

After double checking connectors, my older brother came by with a voltmeter, and found it was jetting juice at the connections to the motor. I pulled it out with a couple of 7/16 wrenches. Without any diagram or anything, he took it apart, and immediately found what he thought was the problem. Sure enough, like others have experienced, there was some grease that had worked its way to the part the brushes rest on. He took a needle, cleaned the groves, and used a cleaner so that you could see shiny copper again.

A little bit of a hassle getting it all back together, with the main issue of keeping the springs under the brushes why we slid it back down into the case. We eventually ended up using the twist ties for garbage bags, and then pulled them out after we got the brushes to stay put. I'm sure others have easier ways of doing it that they have discovered.

Works great now, and the best part was, the local A&P mechanic said you can’t fix those, you have to buy new motors.
 
A little bit of a hassle getting it all back together, with the main issue of keeping the springs under the brushes why we slid it back down into the case. We eventually ended up using the twist ties for garbage bags, and then pulled them out after we got the brushes to stay put. I'm sure others have easier ways of doing it that they have discovered.

That IS the painful part - I use thin dental floss to hold the brushes in while I slip the assembly on the shaft
 
Manual flaps on an RV-8? I've not seen it. Given all of my J-3 time, the no flaps landing is a non-event but my primary strip is 1900' and from one end there are tall trees so flaps do make a measured difference. I don't like eating into that last 20% of the runway.

I'm pulling the motor this weekend and cleaning it.
 
As I have been reading all about these Flap motor issues, I am wondering when mine will show itself up and hope I am not jinxing it by posting this :)

Just went thru my third annual and 360 hours on tac time and all seems to be OK, although I did not take the flap motor apart to check.
 
No Flaps Landing

I agree with the previous post that if we are staying up with our flying skills a no-flap landing should not be a big deal. The things that tend to be a bigger deal are practicing full flap stalls and then not being able to retract the flaps for the return to the airport (it happened to me) or even worse, landing at a distant airport and not being able to get the flaps up for departure (also happened to me). I've had our motor apart twice now - the first time it was full of grease, the second the commutator was filthy, presumably due to an inferior cleaning job the first time.

Proud Partner in N76VM
 
Flaps make some shorter air fields and those with obsticles "possible". A no-flap landing is not really an issue, but it changes the flight envelope.

Has anyone "cleaned" the actuator without dis-assembly? (note: I have not pulled mine yet so that may be a very naive question)
 
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Cleaning "actuator"

Flaps make some shorter air fields and those with obsticles "possible". A no-flap landing is not really an issue, but it changes the flight envelope.

Has anyone "cleaned" the actuator without dis-assembly? (note: I have not pulled mine yet so that may be a very naive question)


I am not sure just what this question asks - the "actuator" is a two part item; an electric motor and a jack-screw assembly. That jack-screw assembly doesn't need attention (unless, perhaps, it has never been used in which case one might prophetically clean out most of the grease they seem to be assembled with). It is the motor that needs to be cleaned, and to do that it definitely needs to be both removed and disassembled.

Silver Fox
 
As I have been reading all about these Flap motor issues, I am wondering when mine will show itself up and hope I am not jinxing it by posting this :)

Just went thru my third annual and 360 hours on tac time and all seems to be OK, although I did not take the flap motor apart to check.

Mine happened at the 500 hour mark on my 6.

It probably wouldn't hurt to take it apart, just to see what tools are involved, and the procedure. It's not difficult at all, even without instructions as I found out. One might even carry those few tools around as well, it wouldn't be that difficult to do out in the field. The only thing that sped it up for me at home was using an electric drill to take off the screws on the panels. But out in the field for my particular 6, I could get by with two 7/16 wrenches, needle nose pliers to pull one cotter pin, a phillip screwdriver (also used for flap motor), string, a needle, and paper towel or rag of some sorts. The needle came in handy for gently cleaning the gooves on the commutator, and also was helpful in keeping those springs down before tying them up with something for the brushes when putting it back together.
 
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Spare motor

Mine happened at the 500 hour mark on my 6.

It probably wouldn't hurt to take it apart, just to see what tools are involved, and the procedure. It's not difficult at all, even without instructions as I found out. One might even carry those few tools around as well, it wouldn't be that difficult to do out in the field. The only thing that sped it up for me at home was using an electric drill to take off the screws on the panels. But out in the field for my particular 6, I could get by with two 7/16 wrenches, needle nose pliers to pull one cotter pin, a phillip screwdriver (also used for flap motor), string, a needle, and paper towel or rag of some sorts. The needle came in handy for gently cleaning the gooves on the commutator, and also was helpful in keeping those springs down before tying them up with something for the brushes when putting it back together.


For a guy that is not flying yet this is an interesting thread, gets me excited to think of things I will need once flying. When you consider the time it would take and the hassle factor to clean the motor in the field, how about just carrying a spare motor. I am not sure if one can source just the motor.

The other thought is has anyone used another actuator, I have seen some farm and tool catalogs for making dump cart lifts?

I guess cleaning the motor at some type of interval is the best preventative measure one could take to hopefully not get stuck someplace. Any ideas on what interval, 100, 200 hrs?

Cheers
 
For a guy that is not flying yet this is an interesting thread, gets me excited to think of things I will need once flying. When you consider the time it would take and the hassle factor to clean the motor in the field, how about just carrying a spare motor. I am not sure if one can source just the motor.

The other thought is has anyone used another actuator, I have seen some farm and tool catalogs for making dump cart lifts?

I guess cleaning the motor at some type of interval is the best preventative measure one could take to hopefully not get stuck someplace. Any ideas on what interval, 100, 200 hrs?

Cheers

Mike, the motor is indeed available from the manufacturer of the flap actuator, Usher Entersprises, for $125 last I checked. A spare set of brushes goes for $25. This is good Murphy insurance to have one or both. :)

Usher @ 503-647-0015.

I have about 350 hours on mine and cleaned it for the first time at my last annual condition inspection in January. It was pretty clean, but I'm glad I did it, if for no other reason than to have the experience of taking the thing apart. I've never had a problem with the motor--yet.
 
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Maybe builders should take the motors apart during the build and clean out the excess grease thereby making it a nearly non-issue.
 
An alternate ?get home fix?

During the 4 years I was building my ?8? I read and reread the ?flap motor? failure posts which always seemed to happen when the pilot was away from home station. With that in mind I fabricated a surrogate flap motor. It?s just a piece of tubing with ?? holes in each end to hold the flaps up. Of course my fly-away kit has the requisite tools to remove the flap motor cover and the motor. And during the build process I had many (too many) opportunities to install/remove the flap assemblies. Seems to work fine but have not tried it in the air. My experience is that if you anticipate a failure and extend some effort to mitigate it the failure won?t happen.
Some of the past posts give the impression that landing a RV without flaps is a concern. I?m not sure why that is a concern but unless you are landing in a 7-11 parking lot it shouldn?t be much of a problem.
 
Mike, the motor is indeed available from the manufacturer of the flap actuator, Usher Entersprises, for $125 last I checked. A spare set of brushes goes for $25. This is good Murphy insurance to have one or both. :)

Usher @ 503-647-0015.

I have about 350 hours on mine and cleaned it for the first time at my last annual condition inspection in January. It was pretty clean, but I'm glad I did it, if for no other reason than to have the experience of taking the thing apart. I've never had a problem with the motor--yet.

No kiddin?, is that all? Best I recall, my electric flap motor kit from Van's for my 4 was close to $600.00, so I was afraid to find out what the cost would be just for the electric motor.

During the 4 years I was building my ?8? I read and reread the ?flap motor? failure posts which always seemed to happen when the pilot was away from home station. With that in mind I fabricated a surrogate flap motor. It?s just a piece of tubing with ?? holes in each end to hold the flaps up. Of course my fly-away kit has the requisite tools to remove the flap motor cover and the motor. And during the build process I had many (too many) opportunities to install/remove the flap assemblies. Seems to work fine but have not tried it in the air. My experience is that if you anticipate a failure and extend some effort to mitigate it the failure won?t happen.
Some of the past posts give the impression that landing a RV without flaps is a concern. I?m not sure why that is a concern but unless you are landing in a 7-11 parking lot it shouldn?t be much of a problem.

Yep, I?d a whole lot rather have flap failure stuck with them up, than in the down situation I had. I?d just keep the speed up another 10 kts on final, these RV?s don?t need that much runway, anyhow.

I was thinking of something similiar that would keep the flaps locked in the up position till I got home. Just gives peace of mind, knowing I would have this ready if it happened again along with a few basic tools to do it. I was thinking of making one end adjustable to get the right fit, but maybe that isn't even needed if I got the end holes on the money.
 
I was thinking of something similiar that would keep the flaps locked in the up position till I got home. Just gives peace of mind, knowing I would have this ready if it happened again along with a few basic tools to do it. I was thinking of making one end adjustable to get the right fit, but maybe that isn't even needed if I got the end holes on the money.

Here is a get home fix.......... http://www.vansairforce.com/community/showpost.php?p=637081&postcount=6
 
Thanks gasman, I was trying to think if something along those lines might work, but wasn't sure, and didn't experiment with it enough when it was out. Glad to know it does. I don?t think it can be much simpler than that. I appreciate it.
 
My flap motor from new would go down and intermittently not retract. Pulled it apart cleaned and refitted.No more problems. Suspect hanging brushes.
 
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