Sure, but I was not speaking in context of aircraft, but e.g. of
multi-day mountain trekking.  Neither I have heard about OSMAnd to be
used for a precise aircraft altitude control.

Dne 18/02/2018 v 00:39 Robert Grant napsal(a):
> While my experience agrees with you regarding accuracy and stability,
> it's still better to know the local pressure setting, especially if
> landing an aircraft without a radio altimeter. Setting an altimeter
> based on GPS sounds quite rare to me.
>
> On Feb 17, 2018 3:12 PM, "Poutnik" <[email protected]
> <mailto:[email protected]>> wrote:
>
>     As being trained in past as the military meteorologist, in pre-GPS
>     era,  I am aware of that. But the offset value is bigger than GPS
>     accuracy of the static value averaged.   BTW, the most handy way
>     how to calibrate the barometric altimeter at unknown altitude is
>     the GPS device. While barometric altimeters have superior
>     short-term accuracy and stability, GPS devices have superior
>     long-term accuracy and stability.  Fortunately, for most personal
>     usage, absolute altitudes are not that important, rather the
>     relative changes.
>
>     Dne 17/02/2018 v 23:35 Robert Grant napsal(a):
>>     I'm pretty sure that none of the devices listed by the op use
>>     barometric altimeters; even the Garmin Glo is GPS altimetry.  GPS
>>     is known for its lack of precision in determining altitude.  In
>>     aviation, old school barometric altimeters are still the gold
>>     standard, but they require periodic barometric pressure
>>     adjustment.  While GPS is great for navigating around the earth,
>>     it would be very foolish to use GPS altitude for landing an
>>     aircraft.  Bottom line:  don't expect any phone with only GPS
>>     altitude to agree precisely with a database supplied measurement.
>>
>>     
>> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon>
>>      Virus-free. www.avast.com
>>     
>> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link>
>>
>>
>>
>>     On Sat, Feb 17, 2018 at 1:41 PM, Harry van der Wolf
>>     <[email protected] <mailto:[email protected]>> wrote:
>>
>>
>>
>>         2018-02-17 19:41 GMT+01:00 Poutnik <[email protected]
>>         <mailto:[email protected]>>:
>>
>>
>>             While Europe subtracts altitude by the correction,
>>             US adds altitude, so the higher value is the
>>             (over?)corrected one.
>>
>>
>>         I didn't know that :) 
>>          
>>

-- 
Poutnik ( The Wanderer )

My Brouter profiles 
https://github.com/poutnikl/Brouter-profiles/wiki

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