PPRuNe Forums - View Single Post - Atlas Air 767 down/Texas
View Single Post
Old 25th Feb 2019, 16:31
  #144 (permalink)  
DaveReidUK
 
Join Date: Jan 2008
Location: Reading, UK
Posts: 15,822
Received 206 Likes on 94 Posts
Originally Posted by physicus
ADS-B data from FR24 gives GPS derived speed, which is the ground speed, i.e. the speed of the aircraft in the horizontal plane only as seen from straight above. If you're tossing a stone off a tower by throwing it away from the tower, it will retain most of the forward velocity but vertical velocity will continue to increase until it hits the ground, thus creating parabolic flight path.
Yes, although the aircraft's trajectory, with at least some thrust being generated, would differ slightly from the purely ballistic trajectory of a thrown stone.

The last few points of the ADS-B data would suggest a flightpath angle approaching -50° and a resolved velocity approaching 400 kts at the last recorded point. That's consistent with the relatively small debris field.
DaveReidUK is offline