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FLT Cancelled - Flap Motor TU

D

David-aviator

Well Known Member
I was ready to taxi this afternoon when the flap motor wouldn't raise the flaps. Total bummer. This is a replacement motor for a grease filled one of 2 years ago. These motors are unreliable, a source of aggrivation and besides that, no darn good.

The side panels were removed to get at the motor but before removing it, the switch was activated one more time - the motor ran! Double bummer, I couldn't get it to NOT run, so now what? A search of the forum on this subject revealed there are dozens of messages on the problem. No solutions, just lots of temporary fixes, like clean the brushes, replace the brushes, replace the motor etc, etc. I remember flying around with the first motor not using flaps out of concern they would not come up - sometimes they worked, sometimes they didn't. What a total pain in the patusch!

Why did Vans ever depart from the simple manual flap system? I would ten times rather have a handle to move the flaps than an unreliable motor that won't when I need it. The flap system should be as reliable as the ailerons, elevators and rudder - it is not. We need a manual kit or a better motor.

 
switch?

I have had no trouble with my flap motor for 3 years. That said, I have also heard stories of motor failures and agree that there have been numerous problems.

I am no electrician, far from it, but could your problem be in the switch?
 
Take a deep breath Daivid.....

OK, isn't that better? (Yeah, I know....it doesn't do much but slow you down for a minute, and doesn't take away the frustration...)

I had this happen after a few hundred hours. Took the motor apart and cleaned the brushes, and it has worked ever since. I could probably do it again in 10 minutes now that I am practiced. I think the only "special" tool I needed was some fine safety wire to hold the brushes for re-assembly, and I just make sure I have that in my fly-away tool kit.

Then I don't let it bother me. Or haven't, but maybe I will when it does it again....

(P.S. - I found the exact same motors - except marked for 24 volts - at a surplus electronics place here in town for $5.00 each. Bought a couple, tested them, and they work fine. I figure I have emergency spares for quite awhile!
 
David I'm sure it's frustrating, but the probability is it was/is a dirty, stuck or worn brush. There is a write up on disassembly/reassembly in either a Service letter or one of the RVaitor's, can't recall which. Don't have them here now but I can research if you can't find it.

Paul, how are you going to convert the 24V motors to 12V?

Larry
 
lrfrey said:
David I'm sure it's frustrating, but the probability is it was/is a dirty, stuck or worn brush. There is a write up on disassembly/reassembly in either a Service letter or one of the RVaitor's, can't recall which. Don't have them here now but I can research if you can't find it.

Paul, how are you going to convert the 24V motors to 12V?

Larry
Click to expand...

The wires are all soldier sealed at connections, there are no quick disconnects. Could be the switch, but I don't think so. The wires going into the unit were moved and I believe that's what got it working again.

I have the motor service bulletin, having been through this once before with the grease. It was cleaned but never did work right and was replaced with a new unit from Vans.

I know there are guys flying around for years without a problem but this is second failure for me which indicates a quality control problem. If you get a good one, you're lucky, if you get a bad one or two, you're unlucky.

I have two 4" DC actuaters that were intended for cowl flaps but the idea was shelved in favor of keeping things simple. They look like the present motor but are much better built. A quick measurement revealed the Vans units are about 5.5" of movement. A bracket 1.5" below the present bracket would work but it would limit flaps to about 30 degrees instead of 40. I am thinking about it.

The source of this motor is http://www.dcactuators.com/

Maybe one of you could check out this product and see if there is a good reason not to continue thinking about it. The 30 degrees flap limitation is really no big deal, just have to adjust an approach speed to whatever the stall speed difference is and it won't be much. I've flown commercial airplanes where flaps were limited to something less than certified full flaps, we simply adjusted the numbers and pressed on.
 
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That actuator looks really good. The only questions I would have are how does the speed (.5"/sec X 4"= 8 seconds to 30 degrees of flap) and load (110 lbs) compare to the Van's unit?

The speed sounds close but since I'm not quite flying I haven't timed it under load. I have no idea what the load rating on the Van's unit is, don't ever recall seeing it published (I haven't really looked for it). I see it has an internal limit switch too, that's nice.

I agree, 30 degrees should be sufficient flaps. Seems to me that you could get back to the full 40 degrees if you chose to shorten the arm on the flap weldment, tho that would probably increase the load on the actuator. Still, if the actuator is strong enough....maybe.

Larry
 
i had a problem a year ago and I got the motor to run also, so I ran them up(pulled the breaker) and flew for a couple mos without flaps.

I feel for you.

What's up with these RA relays?
 
David-aviator said:


Why did Vans ever depart from the simple manual flap system? I would ten times rather have a handle to move the flaps than an unreliable motor that won't when I need it. The flap system should be as reliable as the ailerons, elevators and rudder - it is not. We need a manual kit or a better motor.
Click to expand...

Totally agree with ya David! That's why I threw out the electrics (well, I sold them), and made my own manual flaps with a manual weldment out of an RV-6. I have another one in my garage if you (or anyone) wants to give it a go...not difficult at all, other than making a new cover for the center tunnel.

7-11-07-001w.jpg


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8-25-07-004w.jpg


No electrics for me!;)
 
Flapless

No problem with mine to date but I only lower the flaps to get out of the plane easier. Flapless landings for me 19 times out of 20 unless some 172 is flying bomber patterns in front of me.:mad:

RVs land very sweet clean.:) A technique learned from a really good instructor when I was getting checked out in a Tiger. We don need no stinkin' flaps.

I agree it would be a problem if they were down and wouldn't come up though. Fingers crossed.
 
Flapless

rv6ejguy said:
RVs land very sweet clean.:) A technique learned from a really good instructor when I was getting checked out in a Tiger. We don need no stinkin' flaps.
Click to expand...

I learned that in my 140. Only time I used flaps in the 140 is once during a BFR when my instructor ask to see if they worked.

In my RV I usually use flaps but that same instructor in my BFR wanted me to do all my landing without flaps. He said he does that with all students in planes with electric flaps. Slips are easy in both planes (a lot less aileron required in the RV)
 
lrfrey said:
That actuator looks really good. The only questions I would have are how does the speed (.5"/sec X 4"= 8 seconds to 30 degrees of flap) and load (110 lbs) compare to the Van's unit?

The speed sounds close but since I'm not quite flying I haven't timed it under load. I have no idea what the load rating on the Van's unit is, don't ever recall seeing it published (I haven't really looked for it). I see it has an internal limit switch too, that's nice.

I agree, 30 degrees should be sufficient flaps. Seems to me that you could get back to the full 40 degrees if you chose to shorten the arm on the flap weldment, tho that would probably increase the load on the actuator. Still, if the actuator is strong enough....maybe.

Larry
Click to expand...

With both motors on the bench I did some comparisons.

Vans vrs AEI
Extension 5" 4"
Push Tube Dia .63 .75
Unit Weight 1.5 lbs 2.0 lbs
Limit switches no yes
Full Extension Time 5 seconds 5 seconds
(no load)
Cost $320 $147

Could be Vans unit is special because of the 5" extension. The units available from DC Actuators are in even numbers - 4", 6" etc. Also, the 4" unit will require some modification to install it, the rod end bearing can not be used as is and there isn't enough end plug in the push rod to drill and tap it, its only about .75". I had the unit apart to see how it was made.

The Vans unit worked without hesitation on the bench. I'm inclined to check the brushes and reinstall it and see what happens. If I get really frustrated, I'll call Chad for the drawings or start flying flaps up like Ross. :)
 
Hey Chad,

I think you should go into production with that modification. I'll buy the first one:D

Steve
 
sbarger24 said:
Hey Chad,

I think you should go into production with that modification. I'll buy the first one:D

Steve
Click to expand...

Thanks Steve! I have thought about it, but the problem I see is that if I started selling enough of them, Van's would option it again, and that'd be the end of it. They'd be able to price it much better as a kit option. It definitely has crossed my mind more than once though.:)
 
Be careful!

The Vans unit worked without hesitation on the bench. I'm inclined to check the brushes and reinstall it and see what happens.
Click to expand...
Had the same thing happen, got it back in the plane and it wouldn't work! Pulled it back out, found a wire broke just inside the molded brush case. If you moved the wire just right, it worked great!
 
Old Flap Motor For Sure

The flap motor has been disassembled, cleaned, and reassembled and it works. Here's what I found - a small amount of grease from the gear chamber, some oily dirt in the cap and on the brushes, but overall the unit did not look that bad.

My brain must have had a memory lapse. I've had the motor problem before and thought I replaced it, but there is no record of it. After taking the motor apart, I am reasonably certain it is the original purchased some time in 01 or 02. It is a Motion device, not a Pitman. If I had bought a new one, it would be a Pitman as they came out in 02. Also, stamped on the gear housing under the motor is a 10/01 which may mean October 2001, perhaps a late Motion unit. The problem motors with too much grease were late Motion units. I must have cleaned the unit and it has worked 3 or 4 years since. Well, it just got cleaned again.

Anyway, those of you with the Pitmans should be ok. I'm quite certain I have one of the grease monkey units and will have to deal with it.
 
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Flap cleaning

I have become a pro at cleaning the flap motor. I lasts a year this way.

I get two sandwich bag wires and wire the brush springs back and remove the brush housing. The next step is the key. Clean out the cracks of the commutator. I use a cotton swab and brush on alcohol. Then I find business cards from those pesky insurance salesmen and clean the cracks thoroughly, then use a very fine sand paper and shine the commutator till it looks new. Next attack the brushes and clean them with a cotton swab till they come home clean as well.

I know this will work for you and anyone who buys a new one I'll take your old one off your hands.

Tad "Stripes" Sargent
7A
 
Tad,

Do you want to clean mine? I figure I'm about due for a problem.

When I ordered my -9 fuselage I asked Van's about manual flaps and they told me with the long flaps on the -9 there was no way you could get enough leverage to drop them. That and after my transition training in a -6 w/ manual flaps, I'm very happy with the motor, even if you need to clean it once a year.
 
I wasn't that far off. My flap motor went TU yesterday with less than 85 hours on it. I'm off to the airport to work on it. Bummer as today looks like a great day to go flying!
 
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RV flaps

I have been using mine for the last 19 years, same motor, different switch, but the same set up. Maybe there was just a run of bad motors? :rolleyes: I do find it unusual that so many people are having the same problem. Mayby there is a common thread that all have that is causing the problem. Could iit be a vibration problem? :confused: I wil say this, mine is mounted vertically, behind the seat.:D

Mike Bauer

RV-3 N87LB flying
RV-4 N742MC building
 
flap motors

I think most of the problems with the flap motor is that they don't get enough use, maybe 15-20 seconds per flight. If the motor doesn't start, usually a gentle tap (with switch on) with your elbow or screwdriver is all it takes. Cycle the flaps up and down a few times and allow the motor to warm up and "burn in" a bit. Like many things, it is much happier if it is ran more than a few seconds each flight.
 
With all the problems people have reported regarding these flap motors, has anyone thought to contact Van's and let them know there is a problem?

BTW, I cleaned out my flap motor and it worked just fine for the 25 minute flight I was able to squeeze in before the sun set. :(
 
Build9A said:
I have had no trouble with my flap motor for 3 years. That said, I have also heard stories of motor failures and agree that there have been numerous problems.

I am no electrician, far from it, but could your problem be in the switch?
Click to expand...

AeroElectric Connection talks about the inductive load of a motor can play havoc with a switch, so it is very important to have the proper switch/relay arrangement. My neighbor is an electrical engineer with aerospace experience so I am running this by him since I am now choosing switches for my panel.
 
Chad,

OT, but pertaining to your photos on this thread. What did you replace the profiled aluminum seat back with? Looks like some form of al EML. Did this give you a little more leg room and a little less weight? How is the mod lasting up?

Allan
 
Hey Allan,

That seat mod is an experiment of mine...it may not work out, but my idea is to use those "lightweight" seatbacks with this material to make them breathable...

1-5-08-013w.jpg


1-5-08-004w.jpg


1-5-08-011w.jpg


I have not yet proven them to myself as being comfortable since I can only lean on them against my fireplace at this point, so the jury is still out on that. I don't expect them to work all that well, but I wanted to give it a try.

The seatbacks are made from screen door protectors. See my log entry here...

http://www.chadandbrittne.com/July%202007/Jul%2012-07.htm

and here...

http://www.chadandbrittne.com/July%202007/Jul%2014-07.htm

cool-045.GIF
 
And again...

My flap motor went TU again, this time at 204 hours, 120 hours since the last cleaning.

When I cleaned it the other day, I really cleaned and soaked the motor in contact cleaner. So, the motor will either run forever or burn up in short order.

I'll post back when it goes out again.
 
N941WR said:
My flap motor went TU again, this time at 204 hours, 120 hours since the last cleaning.

When I cleaned it the other day, I really cleaned and soaked the motor in contact cleaner. So, the motor will either run forever or burn up in short order.

I'll post back when it goes out again.
Click to expand...

There is a 6A in the hangar next door, that's a bit over 12 years old, and about 1300 hrs. I'll ask him about his flap motor, if I see him tomorrow. He's never mentioned a failure, but I don't know for sure. I'm just curious.

L.Adamson
 
New flap motor

Flap motor on my RV-8 went out at around 100 hrs with the same problem as everyone else. I cleaned it and put it back in service.At 200 hrs the same problem re-occurred and was followed up with the same cleaning procedure.
I finally purchased a new one from Van and installed it before the problem
occurred again. I do not like the new one as it takes twice as long to extend the flaps.
The old one has been outfitted with new brushes and cleaned and if anything goes wrong with the new one I will reinstall the old flap motor.
Cleaning the motor brushes at about a 100 hour interval is just part of maintenance. I realize that a stuck flap in the down position is cause for grounding the plane, it is not a safety issue when your flaps are inop. for some time.
My 2 cents
 
Would you have a picture of the flap handle with the seats in? I would like to see how it all fits. I think I might know where I can get my hands on a manual flap setup. Thanks
 
rv9aviator said:
Would you have a picture of the flap handle with the seats in? I would like to see how it all fits. I think I might know where I can get my hands on a manual flap setup. Thanks
Click to expand...

This is a problem with forums such as this...

There are thousands of electric flap RV's out there with good success. But you'll get five or ten with problems, and it will look like the sky is falling, because the thousands don't respond on forums.

RV9 flaps take more muscle. They are "stuffed" between "skinny" seats, and very unlike a forward mounted Johnson bar in a Piper.
You'll most likely regret it. Especially with a passenger!

I've followed these builder forums for nearly 15 years, and seldom see a manual to electric conversion, that wished to go back to manual.

L.Adamson --- RV6A
 
rv9aviator said:
Would you have a picture of the flap handle with the seats in? I would like to see how it all fits. I think I might know where I can get my hands on a manual flap setup. Thanks
Click to expand...
Jim,

Contact Van's on this. Back when I was building I contacted them regarding retrofitting the RV-6 flap handle in my -9 and was told that due to the length and design (fowler style) of the flaps you would not have enough strength to lower the flaps. Thus it is not an option.

In reading through the past posts to this thread, it was noted that Van's possibly had a batch of bad motors, and mine might be in that group. I do know of some guys with around the same vintage flap motors who have twice the number of hours I have and haven't had a single problem.

FWIW, manual flaps, as much as I like them, aren't perfect. For one, there is limited room in the RV to pull them up w/o elbowing your passenger, IMHO. Second, I have flown a manual flap RV-6 and had them retract a notch while on final. :eek: This could have been a problem had they retracted at a more crucial time.

L.Adamson said:
This is a problem with forums such as this...

There are thousands of electric flap RV's out there with good success. But you'll get five or ten with problems, and it will look like the sky is falling, because the thousands don't respond on forums...
Click to expand...
I couldn't agree more. The reason for my follow up post regarding my latest flap failure is not to alarm the masses but to inform them. If we don't discuss such issues, they tend to get swept under the carpet. The fix isn't that difficult to do and with luck, I hope I don't have to repeat it.
 
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Both points well taken. I was just remembering the manual flaps on my 57 Cessna 172 and liked them just fine. It makes sense the larger flaps on the 9 would be an issue in manually operating the flaps. I have my flaps all hooked up and they seem to work as they should so no change will be planned. I was wondering how tight it was between the seats with a manual bar and it sounds like it would be in the way. Thanks folks. The sky is now raising towards the heavens just like I wish my 9 could do.:D
 
N941WR said:
Jim,

I couldn't agree more. The reason for my follow up post regarding my latest flap failure is not alarm the masses but to inform them. If we don't discuss such issues, they tend to get swept under the carpet. The fix isn't that difficult to do and with luck, I hope I don't have to repeat it.
Click to expand...

Understood :) And it's good to agree once and a while. Must be the holidays... :D

L.Adamson
 
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