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colin_eyres

having Flap problems? check this out!

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Hi,

I don't know if there are any CT owners suffering the same flap problems that our group had recently with our 2007 CTSW

I thought it might be worth sharing our findings with everyone else.

this is what happened to our aircraft.whether the engine was running or not, flaps inoperative, display flashing, no motor noise,nothing.

leave aircraft for some time, come back to it now all ok.CT checked early in the morning, then in the heat of the day, still faulting.

sometimes in flight it would happen, other times all fine totally random to when the fault would reappear.we tried masters resets, that did not help at all.

this was obviously not a preferable state of affairs to be flying into short strips etc.we had the aircraft flown to a aircraft engineer with a list of the symptoms

and told him to sort it out. sure enough the aircraft came back with a clean bill of health and for a while every thing seemed fine.then one

day for no particular reason the fault reappeared.one of the group members and I decided to have another closer look again and by

chance I jiggled the wires going into the control card {MT- 16] and suddenly the fault was replicated.because there are screwblocks

on the MT- 16 we checked the wires for tightness and sure enough one or two were slightly loose. they were duly tightened but the fault

was still occurring. we had a word with our engineer who said the card must be at fault, and he had a second hand one that we could loan.

that was fitted. and it was still faulting. I thought are we on the right track? on a very,very close inspection of our MT -16 there was a microscopic

crack, and next to the crack there was a miniscule amount of resin missing from one of the soldered pins. we decided to clean the area up and

re solder the pin. we refitted the MT -16 to the aircraft and fired up the flaps, now everything was now fine. I thought if that was our problem solved,

what was up with the loan card, and sure enough on inspection, exactly the same fine crack, in the same position with the same pin problem.

the MT 16 card is not cheap to replace and is a swine to get to remove [firewall, back of the binnacle]. I hope this posting might help some one out there

save time,money and grief if they are having flap problems.

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Marco01   

Got some time my flaps not operating, no noise nothing, and display blinking on -12°. After several tries, it worked in the past, but today, impossible to fixed the issue while flying: manage to land properly with -12°, without touching the tail... I will have a look,at the soldering next WE , and keep you posted... Got a CTSW 2007 as well...

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Hi Marco,

 

Make sure you twist and push every connection on the board wires. Then with the center panel out try flipping the flap lever to another setting and squeezing the flap board in your hands. It has worked for me twice this way and found a crack in the solder on the board.

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Marco01   

Hello roger, Thanks for the tips... before I do anything, and after having read other posts, I will do again some test since I'm maybe thinking that my power supply is too low. Each time I got the flap not operating it's when I have used intensively the battery (Landing light for > 10 minutes under poor visibility condition-even I'm using the Soraa new LED light as you have suggested (needed to go in Manhattan in a chinese shop to get it since not possible to buy it in France!) + Ipad charging+EFIS+GPS+Transponder+radio+cold weather). On top of this, flaps are operated as reduce power (down wind), so limited generator output. Now I remember that each time I decided to cancel my landing due to flap malfunction, set full gas again, and got immediately flaps working again... except last time where I needed to land due to night coming, and didn't open throttle again. So will do some test next WE, and if it's the issue, I will re-consider how to manage the power available form this original weak (but reliable) generator...   

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Marco01   

As promised, done some additional test today, I tried to reproduce again the flap failure with draining high current from the battery (on land), down to 11,6V, but flaps worked properly, then, I flip, twist the relay board and connectors while operating flaps, but no issues. I then decided to turn the small potentiometer on the relay board few degrees clockwise, and went flying: after 5 hours flight with negative temperature, A/P on almost all the time, Ipad charging, etc, flaps worked well, even with no gas (reduce charging from generator). I will see in the next weeks if the problem come back. thanks Colin for your call last week! Very nice to see that somebody from the other side of the Channel is taking care of Frenchy issues!

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Hi Marc,

our flap problems were totally random and went on for about 3 months. sometimes it would be fine for a week or 2.sometimes it would be fine on the ground and fail in flight. we even had

extensive testing on the apron with 100% flap availability only to taxi to the hold and have a 100% failure then to get back to the apron to work ok again.in our case battery voltage didn't make any difference to our problem [engine burning and turning or just with the mags turned on]. Marc I'm only too happy to help anybody with a CT suffering a flap problem. I wished I knew then what I know now about them now!

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Marco01   

Do the flaps work when at high rpm? You can adjust the current some on the board.

Issue on operating the flaps came back last 2 weeks: impossible to get them moving from -12 to 0 when engine on idle. Flap moved immediatelly when open throttle again. If I turn the engine off completely while flying, the flap are not working either: not the best to perform an emergency landing on short grass field!

I believe the issue is coming from a low voltage threshold, may be I should trim the potentiometer in the other directions?

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Hi Marco,

"Do the flaps work when at high rpm?'

 

 

Low voltage can be an issue and this is why I ask the question. I would get to the back of the board and turn the potentiometer screw and raise the voltage. There were some back from the 2006-2007 that had the same problem. They just increased the voltage and it was fixed. Call FD if you need help.

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Hi Marco,

sorry to hear your still having flap problems.can you clarify a point  for me.you say on idle the flaps wont move from 0 to -12 untill you rev the engine.Ok,if you get them to move to say 15 degrees

then throttle back to idle.do you then have control of the other flap positions at idle? if so it seems unlikely that it is a voltage problem.on our aircraft sometime before our problem with the flaps,we had a battery with insufficient oomph to start the engine,we never had a problem with the flap operations tho.do you know the micro switches are making at each flap setting?

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Marco01   

Hi roger and Colin,

I will try to look again at this voltage issue...

And yes the issue came also with other flap position: on downwind, flap didn't work from -12 to 0, then gas again: flaps moved immediately. Base leg, flap 0 to -15: no issue. Then final, flap from -15 to -30: nothing, power again, flap moved to -30.

Will look at the voltage from battery (dynon shows 12.0 v on idle), battery was replaced 3 years ago...

Thanks and I will keep you posted...

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Hi Marco,

well it certainly sounds like a voltage issue now.if the dynon figure is true it sounds way low to me.you should have at least 12.6 volts with the engine running.I suggest you check the battery with

a external volt meter after she's stood for say a day.then start her up,take note of the volts at idle,compare with the dynon for reference purposes.run the engine up the volts should rise,again compare with the dynon.now find the volts needed to operate the flaps.repeat the exercise,this time with a jump start/battery booster connected to the positive side of the battery and the exhaust pipe as the negative[watch out,it gets a bit warm if the neg lead gets near the downpipe] see what the volts are again and if the flaps now work as normal at idle.you could of course try all of this without starting the engine and go on from there.hope this helps with the diagnosis.

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Marco01   

Colin & Roger, some news on this one: moving the potentiometer has helps, but didn't fixed the problem. I still needed from time to time to increase the power to get higher voltage from the generator, and being able to operate the flaps from -12 ° to 0° . 2 weeks ago, while I praticed a landing with the engine turned off completely, I understood the danger to not fixed this when the flap didn't moved again and stays at -12°! in case of real engine failure, I would then need to proceed to an emergency  landing with no flaps in any free field: not nice! so I decided to follow your suggestion: dismount the card (with the help of my 14 years old daughter who get nice thin arms!), replaced the 2 relays by new one ordered from Conrad (17€ with shipment), spray coating again, and install again the card. works perfectly now! i took the time to open the relays: contact were clearly dark and dusted by some carbon. most probably, this influence the current/voltage measurement needed to limit the current demand if flap are operated at high speed. anyway, great thanks again from both of you for your advices: ready now to fly to Corsica mid July!

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Anticept   

In the future, you can check for conditions of the wiring, relays, and everything in between by running a voltmeter from the battery to the motor on the positive leg (runs through the controller) and the negative leg (checks ground), and running the flaps up and down. There should not be more than a volt or two on the meter.

 

What this does, is it provides an alternate path for electrical flow (don't worry, you can't damage a meter doing this as long as the voltage doesn't exceed the meter limit). If there is a poor connection, such as a bad relay, it will use a lot of the energy trying to push the amperage across it, and you voltmeter will detect it.

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Marco01   

Hi Marco, same issue as you. Will try to work it out in the next weeks. Could you please post the model and type of relais?

hello Marculee,

 

here is the right ref: http://www.conrad.fr/ce/fr/product/504206/Relais-pour-circuits-imprimes-Song-Chuan-832A-1C-C-12-12-VDC-30-A-1-inverseur-RT-1-pcs/SHOP_AREA_17391

 

Don't forget that you need two of them.

Since job done 400 hours ago, no issue with flaps anymore.

ring me if you need help: +33 (0) 6 21 57 35 99

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Marculee   

hello Marculee,

 

here is the right ref: http://www.conrad.fr/ce/fr/product/504206/Relais-pour-circuits-imprimes-Song-Chuan-832A-1C-C-12-12-VDC-30-A-1-inverseur-RT-1-pcs/SHOP_AREA_17391

 

Don't forget that you need two of them.

Since job done 400 hours ago, no issue with flaps anymore.

ring me if you need help: +33 (0) 6 21 57 35 99

Thanks a lot! Did you just change the relais or did you have to make other job on the control unit?

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Maury   

Hi Coling, Marco and Marculee,

I have same flap problem as you had. Since a few months ago, flaps running random way. Sometime works, some time not with flashing number position. I checked the Mt-16  and there is not any damaged. I didn't open the two microswichs yet, which is not easy...

I think I'm going to replace the slap elector control swich and the two microswichs, then I hope it work. 

Did you have had any more problems after been replaced the microswichs?

Any information from you will be apprezziate

 

Thanks 

Maurizio

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Anticept   

Maury:

Either your potentiometer has failed on the flap actuator column, or the wires are shorting. Try to place a couple alligator clips to a voltmeter in DC mode on a pair of the wires to the potentiometer, or on the sense wires running up to the control board and run the flaps up and down. Repeat this clamping to 2 of each of the 3 wires until you have completed all combinations. Jiggle the wires around a little bit near the column. If you end up with a voltage reading near zero, the wires are shorted.

A failed pot will spike the resistance. The pot detects flap position, and when failed, it will report incorrect values or cause errors in position sensing from out of range values. Replace, recalibrate, and it will work.

I am writing off that the pot got turned because you aren't saying the flaps are in the wrong positions constantly.

When you do replace it, set flaps to middle position (you might have to do it manually), and the pot to 5k before installing it. Then recalibrate.

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