Turn Coordinator Replacement advice

Brian A Johns

Filing Flight Plan
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BAJ
My turn coordinator is 'sticking'. I talked to the maintenance shop owner (A&P guy wasn't in today) and he said if I wanted to order myself to save a few bucks they would be happy to swap it out. So, just wondering if anyone has advice on where to get the appropriate instrument/best price. Obviously I want a TSO'd appropriate unit. Not trying to buy junk, just trying to save mark-up and get things moving. Aircraft is a Cherokee PA28-180E. I don't think the old one is anything special, just old and tired I guess.

Related, what about overhauls on these? Is that something I should ask for rather than replacement? Again, the mechanic wasn't in today so trying to get a jump on this. I'll talk to him Monday either way.
 
Buy a used one from Teaxas Aircraft Salvage
 
why buy something that might just be worse than yours? just get an exchange unit from century or one of the other rebuilders.


Nothing is fool proof. I had a $2100 Garmin CDI die in under 200 hours and just outside warranty. Garmin is happy to OH it for $1500.

I replaced a TC with a salvage unit and it has been happy for over 100 hours now. So I think you are ****ing in the wind on this one, as I have direct experience with the same TC he has.
 
Because I love spending other people's money, if you fly IFR and don't already have a backup Attitude Indicator, consider taking advantage of AC 91-75 and putting an attitude indicator there. ( https://www.faa.gov/regulations_pol....cfm/go/document.information/documentID/22444 )

Edit: Obligatory photo...
View attachment 67859
Ok you have my attention. What would I be looking for such as is in that photo (make/model info). How much of my money are you spending?
 
That particular one is the RC Allen RCA2610 and the backup battery(ESP) the RCA2610 is $2590 and the battery is $725 and the required inclinometer is $150. They do have a pitot/static model for improved performance, not sure a PA-28/180 would need that. I got this model and battery as it has no pitot/static or GPS dependencies and eventually I want to rid myself of the vacuum system entirely, thus the battery and I'm considering going with the G5 for my main attitude and HSI so I can't backup the G5 with a 3rd G5.
Other options would include:

Sandia SAI-340 for about $3000 with battery(requires pitot/static, if they're actually shipping).

Garmin G5 for $2150 or so with battery(requires pitot/static and GPS antenna or connection to navigator).

MidContinent spinny-gyro models with or without battery($3500, $4000; both +$300 for the required inclinometer)

Dynon EFIS-D10A $2500, (requires GPS antenna install, and purchase of STC from EAA for another $100 for members)

L3 ESI-500 for $5500(requires pitot/static not 100% sure if this meets 91-75)

Edit to add:
I guess I should have mentioned an actual recommendation.

If you have no plans to ever get a G5 as your primary attitude indicator, I'd get that, especially if you have a WAAS Garmin GPS so you don't need another GPS antenna, unless you want it.

If you do plan on a G5 someday, then I'd recommend trying to find out if the SAI-340 is shipping, having the pitot/static advisory data would be nice.

The RCA2610 if you just want a trivial install(and have a place for the battery).
 
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I had a Castleberry electric backup attitude that croaked after only a year and a half after overhaul and I replaced with a used Brittain for $200.

My ForeFlight with AHRS is incredibly sensitive and accurate as a backup as well.
 
Thanks for the replies so far. More questions. I can't fly today so I am on here. I don't know what model turn coordinator I have. All I have found in logs are the original. The aircraft is a 1970 model 180E. About 4200 AFTT. I can't find any log entries where the turn coordinator was replaced.

Question 1: Any chance it would be original? The old literature I have says the original one was an R.C. Allen #80-9. A few pics of my panel below.

Question 2: Really stupid question from a low time pilot and first time owner here. What is the difference in a turn coordinator and a turn and bank instrument? And which one would the one in my panel below be called?

Question 3: In the absence of any further info and pulling it and looking at the number, what would I be looking for to replace this? No autopilot anymore in this plane if that matters. Just trying to get educated before the mechanic clock starts rolling as well as learn something in all of this.


IMG_5218.jpg IMG_5223.jpg
 
Your instrument looks like it could be an RC Allen turn coordinator. The least expensive option is to send out for repair or exchange it for an overhauled one. If you must have new they are about $1k. Yours does not look like an autopilot coupled TC.

A turn and bank instrument has a needle to indicate turn rate instead of the little airplane. The T&B is sensitive only to yaw, whereas the turn coordinator has the gyro canted slightly so it is somewhat sensitive to roll as well as yaw. I actually preferred the old T&B in my old AA1A, but the TC is most common and is supposed to be easier to interpret.
 
Whelp.... get on your back and look under the panel since it’s right dogone there. Use a little mirror extendable from Harbor freight, auntoparts store or Walmart (like $2 bucks) and find out what you got.

But I’m 96.32452 percent sure your will need a Mid-continent 1394T100-7Z turn coordinator. It will be a direct swap, no wiring required.... about a 10 minute job. Remove old, put in new, test.

Buy one used from one of the local salvage yards.
 
Your instrument looks like it could be an RC Allen turn coordinator. The least expensive option is to send out for repair or exchange it for an overhauled one. If you must have new they are about $1k. Yours does not look like an autopilot coupled TC.


I’ll bet money that one is obsolete and not rebuildable.....probably an EGC and a -3 variant and original. I have played this game recently.
 
A turn-and-slip indicator (which used to go by the very poorly chosen name of "turn-and-bank indicator") indicates turn rate only, while the turn coordinator indicates turn rate and roll rate. The former shows this with a needle while the later uses a miniature airplane. Both have an inclinometer (ball).
 
I’m curious.... is your yoke smooth or a little sticky?
 
Any idea why its got all that discoloration like its galvanized sheet metal? Just looks odd to me.
 
Any idea why its got all that discoloration like its galvanized sheet metal? Just looks odd to me.
Mine is the same way. 1969 cherokee 180D. Every once in a while I clean and lube it, with a tiny bit of silicon lube, the type used on bike chains. Never had the shop mention the discoloration. They had it apart this summer to replace worn out Ujoints.
 
Mine is a smooth even silver and so was my Archer. Hoping it wasn't a problem.... Cool.
 
A turn-and-slip indicator (which used to go by the very poorly chosen name of "turn-and-bank indicator") indicates turn rate only, while the turn coordinator indicates turn rate and roll rate. The former shows this with a needle while the later uses a miniature airplane. Both have an inclinometer (ball).
The old name was chosen appropriately for how it was used at the time. If the needle is centered, the inclinometer is a direct indication of bank angle.

And technically, the inclinometer isn’t always an accurate slip/skid indication.
 
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I crawled under and looked. Original model tc anyway. RCA80-9. Now to figure out a suitable replacement.

upload_2018-10-7_18-44-17.jpeg upload_2018-10-7_18-44-17.jpeg
 
AQI is showing a $160 OH price. For that, I’d be all about it. If it turns out you cannot OH it, I would seriously consider just spending the money on a Garmin G5. Find a shop that takes credit cards and do it.

By the time you pay to wire up a new TC, you will be in it for about the same price......
 
Unbolt it your self and send it www.flyaqi.com for overhaul. Mine also drives my Cessna autopilot and was more expensive. The unit comes back with a 8130 form, new glass and painted face.

An A&P or avionics shop will need to install, as the unit most be properly leveled.
 
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By the time you pay to wire up a new TC, you will be in it for about the same price......

Why would that be costly, isn't it just power and ground?
 
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