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Gyro sources

A while back my attitude indicator was acting "lazy" so I checked into having it overhauled. The cost of overhaul was about the same as a new "imported" gyro from Wag Aero. I asked the repair shop the pros and cons of overhauling my TSO'd indicator vs buying a new imported one. They said the new imported one was basically a disposable unit after 500 hours so I opted to have them overhaul it. I sent it to:

Aircraft Quality Instruments of Wichita Kansas
Less than 150 flight hours later it failed dramatically and begin rotating at about 200 RPM's as if I were doing super fast aileron rolls.

Aircraft Quality Instruments told me it would cost $315 to fix it again. NO THANKS to them. I fly IFR and had just finished a 4.5 hour solid IMC flight right before the failure. I'd of course advise everyone else avoid this company.

So question: For those of you still using vac gyros, where have you bought gyros that are reliable or had gyros overhauled? Also, the panel is set with a 7 degree slant so I need to be able to have the gyro, new or overhauled, set for a 7 degree panel angle.

Referrals to any reputable sources would be appreciated.

Thanks
 
Ouch

Sorry for your bad experience, certainly frustrating.

That said, it's kind of harsh. One experience with a company is rather anecdotal is it not?

Time for some glass methinks...
 
A while back my attitude indicator was acting "lazy" so I checked into having it overhauled. The cost of overhaul was about the same as a new "imported" gyro from Wag Aero. I asked the repair shop the pros and cons of overhauling my TSO'd indicator vs buying a new imported one. They said the new imported one was basically a disposable unit after 500 hours so I opted to have them overhaul it. I sent it to:

Aircraft Quality Instruments of Wichita Kansas
Less than 150 flight hours later it failed dramatically and begin rotating at about 200 RPM's as if I were doing super fast aileron rolls.

Aircraft Quality Instruments told me it would cost $315 to fix it again. NO THANKS to them. I fly IFR and had just finished a 4.5 hour solid IMC flight right before the failure. I'd of course advise everyone else avoid this company.

So question: For those of you still using vac gyros, where have you bought gyros that are reliable or had gyros overhauled? Also, the panel is set with a 7 degree slant so I need to be able to have the gyro, new or overhauled, set for a 7 degree panel angle.

Referrals to any reputable sources would be appreciated.

Thanks

I have used TGH Aviation (formerly "The Gyro House") in Auburn, CA for many years. http://tghaviation.com/aircraft-instrument-services/
Not saying that I have never had any issues with their work, but they seem to do a good job. Note: At one time I worked for repair facilities and so we cycled many units through. Therefore, the few hiccups are a very small percentage.
Just out of curiosity, are you doing a lot of rolls? If so, that could be causal to your failure(s).
 
It's Your Skin

4.5 Hours in solid IMC in a 4... Not a lot of wiggle space or fuel reserve.

Regarding AI failure, perhaps a gentle (and lucky) reminder that any of it can and will fail.

A local RV 10 that was built for and flown in IMC just had an overvoltage on the ground before takeoff. If fried both EFIS and the Vertical Power box in a heart beat. Had it happened in flight in actual IMC , the ship in question has no steam or stand alone battery backup glass. Both EFIS could be powered with either of two main 12V Batteries, the spike happened so fast it fried the internal saftey fuses of the large format EFIS units. However, they were instantly black panel non flyable displays.

I have had seen TSO'd steam AI's fail just as you have described. I have also had 4 out of 6 modern EFIS units fail for a host of reasons. None of the failures were over voltage or under voltage.

It's your skin...

There is a good reason air line transport AC have 4 displays with multiple stand alone AHRS and battery backup gyro AI's and a stringent maint. and overhaul schedule.
 
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Margins

All good points - and your experience with 4 of 6 glass panels is some of my reluctance to go that direction. As often as my Ipad says "this app will now force close" I still sort of prefer a bearing that usually makes some noise before it fails and a vac pump that has a wear indicator port to inspect.

Actually my RV-4 has 54 gallons of fuel in tanks that are simply larger versions of the "standard tanks". Yeah, I'm sure Vans isn't thrilled about it, but I hired an Aero Engineer to review and design the change, so I'm comfortable with it.

I used to fly with two engines, two vac systems, two alternators, etc.
Now in my own plane, with only one engine, I fly IMC but only with a few thousand feet between the clouds and the ground (and not at night) to give some reactionary time between breaking out and touching down. In addition to my vac gauges I have the iPad/Stratus AHRS and a true trac A/P that will keep wings level without a functioning vac gyro, so I do provide myself some options, but still want to do all I can to assure an Attitude Indicator that also works..... usually : /
 
True

Its not a matter of if, but when. A blank glass panel will definitely get the pucker string a little tighter.
cj


4.5 Hours in solid IMC in a 4... Not a lot of wiggle space or fuel reserve.

Regarding AI failure, perhaps a gentle (and lucky) reminder that any of it can and will fail.

A local RV 10 that was built for and flown in IMC just had an overvoltage on the ground before takeoff. If fried both EFIS and the Vertical Power box in a heart beat. Had it happened in flight in actual IMC , the ship in question has no steam or stand alone battery backup glass. Both EFIS could be powered with either of two main 12V Batteries, the spike happened so fast it fried the internal saftey fuses of the large format EFIS units. However, they were instantly black panel non flyable displays.

I have had seen TSO'd steam AI's fail just as you have described. I have also had 4 out of 6 modern EFIS units fail for a host of reasons. None of the failures were over voltage or under voltage.

It's your skin...

There is a good reason air line transport AC have 4 displays with multiple stand alone AHRS and battery backup gyro AI's and a stringent maint. and overhaul schedule.
 
I keep an electric TC on a toggle switch. Normally off in VFR. The ball works regardless. If the WX is a factor I test it before launching. You could do the same with a stand alone electric AI. Or two of them, in addition to the vac AI.

Ceramic ball bearings should provide more hours of service, but I am not sure how small they are available. One of my customers has a shop that rebuilds airline size gyros with ceramic bearings. The skill and integrity of the rebuilder would trump bearing type, but ideally, I would want both to be the best available.

FWIW my GRT mini X has been a solid performer. Also my MGL extreme.
Time will tell. A small 18 V Li-ion battery from a cordless drill would run a pair of Mini X effis for several days.

If you find a good gyro shop please post or send me a PM.
 
A local RV 10 that was built for and flown in IMC just had an overvoltage on the ground before takeoff. If fried both EFIS and the Vertical Power box in a heart beat. Had it happened in flight in actual IMC , the ship in question has no steam or stand alone battery backup glass. Both EFIS could be powered with either of two main 12V Batteries, the spike happened so fast it fried the internal saftey fuses of the large format EFIS units. However, they were instantly black panel non flyable displays.

I have had seen TSO'd steam AI's fail just as you have described. I have also had 4 out of 6 modern EFIS units fail for a host of reasons. None of the failures were over voltage or under voltage.
.

I'd like to see the complete power schematic before attaching any significance to that story. I find it very difficult to believe that a spike could be generated by the plane's on-board equipment that would be both large and quick enough to overpower a properly designed OV protection circuit. Now if it didn't have one, or there was a lightning strike, that's a different story.

Charlie
 
The RV 10 is not mine. I just got the phone call for D Sub pins as the owner starts to rebuild for a newer Vertical Power. As it was relayed to me, the over voltage protection did work the first time. After he found the breaker tripped, he tried a reset (As one does) and that is when it got very expensive and dark. I do not know what OV protection was in front of the Vertical Power, but the owner did state that he felt the VP should have prevented any spike beyond it. Both AFS Efis fuses and all three position lights were nuked.

It was an internally regulated alternator. Also the electrical and avionics did pass two inspections. One from the RAA and a second from Transport Canada as the 10 was legal and approved for IFR flight. Over 100 hours since new and signed off for IFR.
 
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So question: For those of you still using vac gyros, where have you bought gyros that are reliable or had gyros overhauled? Also, the panel is set with a 7 degree slant so I need to be able to have the gyro, new or overhauled, set for a 7 degree panel angle.

Referrals to any reputable sources would be appreciated.

Thanks

I used the following company when my DG started acting funny and was very happy with their service. They will do a swap with core, rebuild yours and send it back or sell you a nice used one off the shelf. I did the last option since my DG was missing a required MFG label, which made it unserviceable.

Name : GEORGETOWN INSTRUMENT SERVICES INC.
Phone: 512-352-9000 Fax: 512-352-9001
Website: georgetowninstruments.com
Name: EFRAIN LOPEZ (owner)
E-mail: [email protected]
 
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