Originally Posted by
DIBO
For the rest, don't think I can add much more to BFSGrad's post, but as I already made some screenshots, I can as well include them here (altitudes given are ADS-B output, so NOT corrected with QNH)
Add about 160' for height AMSL, minus 30' for AAL. Heights shown as 0 on FR24 may not necessarily be on the ground..