PPRuNe Forums - View Single Post - Polish Presidential Flight Crash Thread
View Single Post
Old 16th Jan 2011, 07:47
  #1054 (permalink)  
SadPole
 
Join Date: Jun 2010
Location: East of Eden
Posts: 157
Likes: 0
Received 0 Likes on 0 Posts
Janeczku

Yes, this was a very accurate estimate of the flight path based on the transcript alone. But, your chart assumes pretty consistent real descend rate. If I remember correctly, this was the main controversy at the time your chart was being discussed. If the descend rate was constant, then at least one of the ATC (on course, on path) calls would have been wrong. The descend rate was not constant – they INCREASED it most likely as a result of observing the falling slope of the ravine on Radio Altimeter. Meaning they did not even listen to the ATC but most likely tinkered with controls based on Radio Altimeter readouts alone. If the ATC says "on course, on path", why increase descend rate?

I remember that controversy, I even thought that maybe they unknowingly discovered some ground following mode in the ABSU that changed the descend rate for them based on RA. I even went at that time through the ABSU schematics to discard that possibility (yes – I'm nuts ).

See the fragment of the MAC/IAC Figure 45 I was talking about.
Red line – Radio Altimeter readout.
Blue line – Altitude above road nearby
Green line – ideal glidepath.


Last edited by SadPole; 16th Jan 2011 at 08:06.
SadPole is offline