G3X and G5 altitude adjustment

[Flyyak]

Is there a method to adjust altitude settings between G3X and a G5 without adjustment from Avionic shop. My G5 depicts 40’ higher than my G3X.

 

[Walt]

Nope…afraid not.

 

[Jetmart]

Is there a method to adjust altitude settings between G3X and a G5 without adjustment from Avionic shop. My G5 depicts 40’ higher than my G3X.

This seems to be a common problem. Although I don't like it it is within legal specs if we were in a certified airplane. My avionics guy says he sees this situation often with specifically the G5.

 

[500AGL]

If your avionics shop hooks up pitot/static and calibrates them they should be within 5-10'. Can't say I've seen a software update change the cal but I suppose it's possible.

 

[Walt]

If your avionics shop hooks up pitot/static and calibrates them they should be within 5-10'. Can't say I've seen a software update change the cal but I suppose it's possible.

Not really true, if you calibrate both the G5 and GSU25 then they typically will be very close within about 10-20' difference from 0-20k ft,
but the tolerance is +/- 20 ft at SL for each unit, so even with both units within spec, you could theoretically see a 40' split at SL, tolerances increase with altitude.

 

[Steve]

The wizards at Garmin should program logic into the G5 so that when the GSU-25 ADHRS is providing data to the G3X, the G5's internal ADHRS is not used, thus resolving the altitude discrepancy between the G5 and the G3X. If the GSU-25 goes offline, the G5 becomes fully functional.

 

[Walt]

The wizards at Garmin should program logic into the G5 so that when the GSU-25 ADHRS is providing data to the G3X, the G5's internal ADHRS is not used, thus resolving the altitude discrepancy between the G5 and the G3X. If the GSU-25 goes offline, the G5 becomes fully functional.

That would defeat the purpose of having an independent backup?

 

[skylor]

Confucius say, "Man with two watches, never know correct time.”

Skylor

 

[lr172]

Confucius say, "Man with two watches, never know correct time.”

Skylor

Unfortunately historians edited out the second part where in he continues "... but man with one watch foolishly think he know correct time." In its original form it was a fable about the inherent perils of no redundancy Obviously kidding but couldn't resist.

 

[Steve]

Yeah, but

That would defeat the purpose of having an independent backup?

I went back and forth on this while installing the G5 in my G3X world. Unless the G5 has its own pitot and static system, it will never be a true independent backup system.

 

[Vern]

G5 indicated altitude adjustment

My local avionics shop says it’s a simple easy adjustment to make so all altimeters read close to same altitude

 

[moespeeds]

My AV30 does the same. Always reads 20-50 feet off from what my AFS4500 reads. Same Baro setting, same pitot/static lines.