I`m having strange issue with GPS rescue - BF 4.2.8 . 
When "altitude mode" is set to default "maximum altitude", my drone, is rth as the same altitude it was flying.
As I understand, this should not work that way, but ascend to 50m (default BF setting) OR max flight altitude (if it exceed 50m).
When I tried gps rescue, (for test purposes I was flying at low altutide, maby 2-3m and I was ~150m from home point), after I flipped gps rescue switch, the drone did not ascend but instead it started to rth at the altitude of 2-3m and in fact crashed in high grass.
See vid in attachment.
When I changed altitude mode to "fixed altitude", in the same situation it ascended to 50m and then rth. In fact max altitude would make no sense for me if working like that. Any ideas if it a bug or config issue?
Drone is flywoo explorer v2 with FLYWOO GM8 MINI V2.0 GPS, altitude readings are fine. Many thanks for help

dvr:
https://we.tl/t-0GvUmo3EMg

Do you have OSD or telemetry/blackbox logs showing the altitude? If you're only using a GPS and no barometer, the GPS altitude can be very inaccurate and fluctuate wildly.

Unfortunatelly I don`t have any logs from this situation, only readings from OSD. Strangly, with "fixed altitude" setting at the exact same location it ascended to 50m firstly

You have not confirmed if you have a barometer? Do you have the analog or the HD version of the Explorer LR v2? The analog version comes with the GOKU F411 FC which does not have a barometer onboard. The HD version comes with the GOKU 745 stack that has an onboard barometer.

Did you have the altitude posted on the OSD to be exactly sure you know what altitude Betaflight thinks its at? I saw your DVR but it has no Altitude or any other OSD.

Also ensure you have a GPS fix before take off as the altitude readings are a combination of GPS altitude and Barometer altitude and this goes very wrong if we take off before a GPS fix. 

For me during my tests with a GPS and a Baromter on board 2 of my quads I get the same results as advised in the BetaFlight wiki.

If you look at the Betaflight wiki: https://github.com/betaflight/betaflight...escue-mode

MAX_ALT is the old setting, the altitude will be gps_rescue_initial_alt, or the maximum altitude recorded during flight +15m

FIXED_ALT, the quad will always try to return to the height set (gps_rescue_initial_alt)

CURRENT_ALT, the quad will return maintaining the readed altitude during the rescue activation (not suggested)

I have Explorer LR v2 hd version with onboard barometer. I have altitude on OSD and during the flight it was showing 2-3m so it was correct, its not shows on dvr as it was added as a subtitles as it was removed when I processed the video to cut it. I had 5 sats fix. I just wanted to make sure I got it right. I must give it another try and see how it behaves, maby it was just a tempolary issue. Thanks for explaining.

(16-Jun-2021, 10:25 AM)Buartek Wrote: I have Explorer LR v2 hd version with onboard barometer. I have altitude on OSD and during the flight it was showing 2-3m so it was correct, its not shows on dvr as it was added as a subtitles as it was removed when I processed the video to cut it. I had 5 sats fix. I just wanted to make sure I got it right. I must give it another try and see how it behaves, maby it was just a tempolary issue. Thanks for explaining.

Test it again and report back how it goes.

A 5 satellite fix is not sufficient in my opinion for rescue. Betaflight recommends default minimum 8 satellites.

If i don't get 8 sats locked I'm not taking off.