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Old 14th Sep 2007, 18:38
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Lemurian

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Flyingnewbie
o not forget the forward push from the right engine...
and Dani,
we don't know how slippery the runway was, but we know for sure that engine 2 was still at forward trust. Even with full brakes you will not manage to get any usefull deceleration.
Please refer to the Transasia FDR graphs and the discussion on pp 30 to 36 of that report.They achieved better deceleration, obviously.
What's more interesting, though, is that (refer fig 1.11-2, page 34 )
  • originally, without any braking to speak of -time tags 30 to 39 -, they had a deceleration of 1m/s/s, therefore due to aerodynamic drag and 1 T/R only.
  • Then between Tt 40 and 48, the effects of a skid with a working antiskid system (brake pressure is way too low for the pedal position), but they still achieved 1.3 to 1.6 m/s/s.
  • On reaching a less slippery surface,- Tt 49 to 15 -, a deceleration of 2m/s/s was reached, still with the antiskid modulation but now, max brake pressure is achieved.
Unfortunately, the size of the CGH graphs don't allow such analysis.
Therefore, I stand to my arguments : That runway was very slippery.
The Transasia report is found
Here.
Lemurian

Last edited by Lemurian; 14th Sep 2007 at 18:42. Reason: Clarity
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