Originally Posted by Lemurian
PBL is referring to the deceleration achieved by this aircraft taken from the FDR print-out. A very *poor* braking indeed.
Poor, but still more than nothing.
Originally Posted by flyingnewbie10
That's what I thought.
However if (if) he was based on the FDR the information might not be accurate as we still don't know how slippery the runway was.
The figure PBL quoted was
observed deceleration, i. e. the deceleration that was actually achieved in this landing (derived from the ground speed plot, and supported by the longitudinal acceleration pliot).
This is independent of
how it was achieved, and under what conditions.
What is, is.
What we know is that the crew thought that the runway was slippery. And this could explain their hesitation to apply manual braking before spoiler extension if after all such hesitation showed up to be expected from a crew in the same situation.
If you expect poor braking action, you must brake as soon as possible to get the most out of the available distance. Not delay it.
Originally Posted by marciovp
Also if there was some plans for the A320 to land at Congonhas in a raining slippery night efforts should be made to make the plane as light as possible, no?
No. Taking all parameters into account one arrives at a maximum landing weight for a given configuration/airport/runway condition/... Either from tables or (I guess) the LPC ("Less Paper in the Cockpit") computers.
One can go up to that weight. One does not have to take into account every possible adverse situation, like keeping the thrust on and lack of ground spoilers during roll-out.
Bernd