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Garmin G5 Static - Altitude

ten4teg

Well Known Member
Just got a Garmin G5. When I set the Baro to field elevation, the baro does not match the current pressure. It looks like it needs adjustment. Anybody know a way to do this? I don't need IFR accuracy. Thanks [email protected]
 
Mine is off about 70 feet.

They can easily be calibrated with a (high accuracy RVSM preferred) pitot static test box, you have to take it up to 20K for the cal procedure. I find they can drift a bit but have not seen anywhere near 70'.
 
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Not saying it's right, because a 70' error would really bother me as well, but even for IFR the allowable error on an altimeter is shockingly large. Going out on a limb here, but I seem to recall the AIM talking about +-75'. Does that sound right?

Also, is it possible that the error isn't actually that large? My home runway looks dead flat, but according to the approach plates, field elevation is 1408, measured at the threshold for rwy 19, and drops about 40' by the time it gets to the other end. The runup pad (about midfield) consistently shows 20' lower than published field elevation, which seem logical based on what the plate shows.
 
I added a G5 to my panel as a backup, in addition to my AFS EFIS and to the old round gauge still in the panel. I just had the entire suite IFR-certified. Interestingly, the EFIS and the G5 were exact, and matched. I still have to set three different altimeters, but the old round gauge didn't make the cut and got placarded as "VFR only".
 
When you have one altimeter, you always know exactly how high you're flying.

When you have two, you're never quite sure.

- mark
 
Not saying it's right, because a 70' error would really bother me as well, but even for IFR the allowable error on an altimeter is shockingly large. Going out on a limb here, but I seem to recall the AIM talking about +-75'. Does that sound right?

Also, is it possible that the error isn't actually that large? My home runway looks dead flat, but according to the approach plates, field elevation is 1408, measured at the threshold for rwy 19, and drops about 40' by the time it gets to the other end. The runup pad (about midfield) consistently shows 20' lower than published field elevation, which seem logical based on what the plate shows.

Allowed error (91.411) depends on altitude.
With 2 altimeters the split could be double the error if one was on the minus side limit and the other was on the positive side limit.

ALTITUDE / ERROR

0 / 20
500 / 20
1,000 / 20
1,500 / 25
2,000 / 30
3,000 / 30
4,000 / 35
6,000 / 40
8,000 / 60
 
G5 Calibration

Just got a Garmin G5. When I set the Baro to field elevation, the baro does not match the current pressure. It looks like it needs adjustment. Anybody know a way to do this? I don't need IFR accuracy. Thanks [email protected]


Tom,

While there is a static cal procedure provided in the installation manual, you should not have to perform it right out of the box. Reach out to us via email at [email protected] and we can get an exchange set up for you if you would like.

Thanks,

Justin
 
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Terry,

While there is a static cal procedure provided in the installation manual, you should not have to perform it right out of the box. Reach out to us via email at [email protected] and we can get an exchange set up for you if you would like.

Thanks,

Justin

Thanks, but I'm not the original poster, just an interested bystander :)
 
I'm having the same issue with my G5. It's off by about 90'. Is there really no way to calibrate the Kolsman window without doing a full static recalibration? Can you not just program an offset?
 
I may have a similar issue

I recently installed a pair of G5's and there is about a 60' difference between the altimeter and the G5.

I'm planning to fly tomorrow to a different airport so I'll have another datapoint.

OP, thanks for posting this.

Edit: Didn't realize this was a 2 year old thread until after I posted.
 
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I'm having the same issue with my G5. It's off by about 90'. Is there really no way to calibrate the Kolsman window without doing a full static recalibration? Can you not just program an offset?

+1
Help us Garmin

I recently installed a pair of G5's and there is about a 60' difference between the altimeter and the G5.

I'm planning to fly tomorrow to a different airport so I'll have another datapoint.

OP, thanks for posting this.

Edit: Didn't realize this was a 2 year old thread until after I posted.

Having done tons of alt checks and calibrations, I don’t think an offset is a great idea as it offsets the entire range. Some other vendors offer that but I often end up with a full cal if I dial in an offset on the ground.

I’ve done lots of G5’s and don’t recall ever seeing a large error (maybe 40’ max) so I’d be a little suspect about the reference you’re comparing it to.
 
Mine has been different since started flying

I have a G5X and a GDU465. Current flight hours 45.5.

Current display check.
Baro setting: Displayed Alt:
G5X 30.10 890
465 30.10 930 -- 40' difference

Baro setting: Displayed Alt:
G5X 29.92 730
465 29.92 765 -- 35' difference

If I only had the 465 it would be perfect, I rely on the 465 which is consistent with the airfield elevation. I consider the G5 as a backup and would add 40' if I was relying on it.
 
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I’ve done lots of G5’s and don’t recall ever seeing a large error (maybe 40’ max) so I’d be a little suspect about the reference you’re comparing it to.

The reference might be the issue for me. I flew to an unfamiliar airport and the G5 was dead on the published airport altitude at 5150 using the local AWOS barometric reading. My altimeter and RMI uEncoder both read something different.

My home airport (KBJC) elevations range from 5566' all the way to 5673', depending on location, so I'm not even sure what the exact elevation is at my hangar.
 
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