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  #11  
Old 06-01-2019, 12:39 PM
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Walt Walt is offline
 
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Quote:
Originally Posted by chris mitchell View Post
So we connected the G5 to reference ASI. Consistently across speeds from 200kts down to 60kts, it was 2-3 kts at least out of agreement except at about 110kts. We have opted to ask for a replacement unit. It’ll be interesting to see how that stacks up.

Chris
I don't think you're gonna get much better than that as far as accuracy, TSO'd AS indicators limits generally range from 2 at the low end to 7 mph error at the upper end.

If you were to ask me I'd say that's pretty darn good at 2-3kts error, most analog instruments are double that.

And is a few knots really that important?

As far as the altimeter matching your transponders output that's meaningless from an accuracy standpoint.
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Last edited by Walt : 06-01-2019 at 12:42 PM.
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  #12  
Old 06-04-2019, 09:24 AM
chris mitchell chris mitchell is offline
 
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"As far as the altimeter matching your transponders output that's meaningless from an accuracy standpoint. " I totally take your point!

The altimeter is at least 10 years old, over 550 hours on it. Maybe its time for a check and recalibration if needed. How often should that be done, or is it simply a matter of noting if the indicated altitude on the ground is appropriate for the QNH?

Will report back on the G-5 in due course. THe instrument itself and the kit for intallation with the magnetometer are nicely done.

Chris
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  #13  
Old 06-25-2019, 01:32 PM
chris mitchell chris mitchell is offline
 
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Default It was the G5!

So - we got a replacement G5 unit. Installed it, flew it. Agreed with the ASI within 1-2 kts. So we conclude it was the original G5 unit.

Now we are grappling with the GMU-11. Found some helpful stuff on another thread, so testing is in progress.
Thanks for the comments and suggestions, much appreciated.

Chris
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RV-8, QB, built, flown 150 hours, sold;
RV-4 - attempted repair, rebuild and remediation - abandoned and junked ;
RV-4 fuselage and wing kits - both at QB stage;
2015-2018 dues paid!
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