Turn Coordinator Failure (Red "ELEC" Flag)

Sinistar

Sinistar

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Brad
For a Cessna 182p, looks like original equipment , no auto pilot, does have a wing leveler though.

Yesterday we noticed the red failure flag on the Turn Coordinator. We checked the breaker and it didn't pop (still in). Alternator current draw seems unchanged. So a couple of questions:

1.) To mark the instrument face INOP, I believe I should cover it. But can i leave the ball indicator uncovered since it is gravity only?

2.) To properly INOP the TC, I believe the power needs to be removed. It does have a dedicated breaker, but I don't think it can be pulled out manually. What should be done?

3.) Any rough estimate on cost and downtime to repair this?

I want to use our plane for my checkride and can't imagine the DPE wanting to do the ride with no TC.

Just wanting to fix this instrument. Not interested in solving with newER digital avionics at this time.
 
Gonna guess. $500-$1500 for a new instrument, based on Aircraft Spruce prices (maybe less used; maybe it can be repaired, loose wire, etc.).

Labor? 1-2 hrs? $50-80/hr?

My problem is my avionics guy is always 3 weeks out for a squeeze-in appointment for a few hours work (he's booked through July 2018 for time consuming full panel or ADSB work.
 
Instrument repair turn around times are usually short. Usually a day or two. Shipping takes longer. If you are in a hurry you can get a rebuilt unit then send yours in for a core.

Eyeball the wiring before declaring it dead. TCs usually fail with a nasty grinding noise. Of course other failure modes are possible.
 
Get one on overhaul-exchange basis. You don't have to wait for the to-from of sending your unit for O/H that way. Only 100 bucks more, super quick, and the TC installation is simple, it's just a cannon plug.
 
Couple things before you do anything... A TOMATO FLAMES and FLAPS. Any Turn Coordinators in there? It is not required for VFR flight.

Some CFI will opine about this bit: So long as you're not banking excessively you should be able to use your attitude indicator for the hood time. I don't think you are expected to do standard rate turns.

Also, a "wing leveler" IS an autopilot. Just not an advanced one.
 
Yes, do the exchange. I forget how much my recent exchange was but It was not expensive. Your mechanic can do the simple install so no need to wait for your avionics shop.
 
Clark1961 said:
TCs usually fail with a nasty grinding noise.
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Yeah I always wondered if that nasty grinding noise was normal...now its really, really quiet :( I did check the wires as good as I can see them, nothing looks wrong from behind anyway...but its a mess in there. Gonna call the shop and if there is an exchange I can do in advance it will really save some time.
 
Sinistar said:
Yeah I always wondered if that nasty grinding noise was normal...now its really, really quiet :( I did check the wires as good as I can see them, nothing looks wrong from behind anyway...but its a mess in there. Gonna call the shop and if there is an exchange I can do in advance it will really save some time.
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Unscrew the connector on the back check the voltage on the two pins in it, it should be buss voltage, if it is the unit is bad. Find the local part time A&P that does simple crap like that for beer money.

As for Inop-ing it, disconnect the plug secure that, label it Inop and give the formentioned A&P a six pack of good beer to write it up in the logs.

Bob
 
Update: Quote from avionics shop is just over $700 for a rebuilt replacement, more if it is something non-standard. Plus 1hr labor.

Only dowside is they need to pull it first to get correct part number, then 2 days delivery of replacement. So looking at 3+ days downtime..not a big deal but nearing completion of PPL so not keen on delays now. Then again, best to have the panel all in good working order vs explaining INOP this and that to the DPE.
 
Sinistar said:
Update: Quote from avionics shop is just over $700 for a rebuilt replacement, more if it is something non-standard. Plus 1hr labor.

Only dowside is they need to pull it first to get correct part number, then 2 days delivery of replacement. So looking at 3+ days downtime..not a big deal but nearing completion of PPL so not keen on delays now. Then again, best to have the panel all in good working order vs explaining INOP this and that to the DPE.
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Find an A&P to do the R&R or supervise you doing it. Best case is you pull the TC, procure the rebuilt replacement and reinstall. A&P hears it spin up and provides log entry for minimal charge. Total might be $400 with shipping.
 
aqi is 425 exchanged, order one, and find that local that works for beer, I am expensive, i only drink good beer.......
 
unsafervguy said:
aqi is 425 exchanged, order one, and find that local that works for beer, I am expensive, i only drink good beer.......
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AQI stands behind their work in my limited experience.
 
Skyrys62 said:
Getting this repair all worked out makes you a turn coordinator coordinator?
ha! ba dump psssss!

ok, aside from the stupid pun, (and not to hijack the thread) but I have a question regarding TC operation.

Saturday as I was rolling onto the runway, I noticed the turn coordinator indicating a pretty steep left turn (I was turning right onto the runway)....and also the ball waaaay off center to the left.
It slowly leveled itself as I accelerated down the runway, and appeared normal for the rest of the flight.
Also, after landing, it happened again on the turn out to the runway for another flight.
Is this normal and I've just never noticed it.. or is there something possibly awry in the works?
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Normal. Also normal to check operation while taxiing to position. One of those checks you do when other people are gawking or talking about their stock options.
 
Update: Flew plane to shop today. Turns out the Turn Coordinator is a autopilot version (for the wing leveler). They recommended going with a standard one and disconnecting the wing leveler as its uses the vacuum system (not sure I totally understand) and would need even more work to get that all working properly. We have never used the wing leveler other than to try it out. So won't be missing it...for now I guess.
 
I wouldn't be dismissing the notion of having an already-installed single axis autopilot so quickly. That sounds like a Brittain vacuum AP system, but have no idea what airplane we're talking here. Vaccum AP were usually found on mooneys. Pipers are Century that use DG and AI for inputs, the Piper Century that's TC-based was electric. At any rate, that's worth a lot of AMUs alone, in order to replace the capability. I'd look into what it would cost to get running again.
 
My vacuum powered brittain wing leveler not only tracks the heading bug in the DG but also Nav 1 and Nav 2. There are add-on pieces to expand to those capabilities.

Brittain expects to be compatible with the G5 HSI but I haven't seen an interface drawing yet.
 
Sinistar said:
Update: Flew plane to shop today. Turns out the Turn Coordinator is a autopilot version (for the wing leveler). They recommended going with a standard one and disconnecting the wing leveler as its uses the vacuum system (not sure I totally understand) and would need even more work to get that all working properly. We have never used the wing leveler other than to try it out. So won't be missing it...for now I guess.
Click to expand...

Hmm. You’re probably long past this but I missed the thread. Was reading and about to tell you that your TC is a special one. If that’s a Cessna/ARC 200 Autopilot in your plane. (What they came with. Or a 300 which is the same unit with a heading bug on the also more expensive DG.)

If it’s stock Cessna, NOTHING about that Autopilot needs vacuum at all and your shop are idiots. That’s a completely electrical system. TC sends bank voltages to the Cessna Autopilot and that’s it in the Cessna/ARC 200.

If it’s a 300, same deal for wing leveling mode, but the *DG* is vaccuum driven and has additional voltage output for left/right of the heading bug setpoint for HEADING mode.

And... if you ever add a GPS you want the 300. GPSS roll steering can drive the left/right voltages to the Cessna/ARC AP and fly GPS track.

Our 200 is in sad shape and does nice s-turns about a course, but it works kinda. If the TC gets old/sloppy and bounces left/right in turbulence as the gyro and bearings wear out, the AP will simply follow it. If the TC is “calm” the AP will be too.

And then there’s NAV tracking which is entertaining from the VOR/ILS receiver to either the 200 or 300 AP. That’s a whole different mode and story.

It’d be nice for 200 owners if someone would field approve or otherwise approve feeding GPSS in through the TC voltages with a switch and annunciator to show if you’re using the TC or the GPSS but FAA likes that stuff going in through a heading mode more. Literally the same thing, electrically though.

Probably not a huge market for it, though. The ARC stuff is nearly unsupported at this point.

But if yours works and you’re getting a new TC anyway, I’d hate to disable it because the shop wants to use some other non-AP output TC instead of just rebuilding yours. They’re being lazy.

It you already made the call to ditch the single axis AP or it wasn’t working right, mmmkay. But that sucks that they a) Didn’t want to put the proper TC in, and b) Told you it used the vacuum system.

Only the DG portion of that AP System needs vacuum and that’s just to run the DG you’re looking at anyway. The indications from that DG are just left/right voltages driven by the location of the heading bug.

They kinda screwed you with bad info.
 
PS. If it has some non-Cessna single axis AP, all bets are off on all of the above. LOL.
 
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