Let's edit that transcript, remove the sensationalism and concentrate on the landing phase:
"
15:45:04.2 [EGPWS] Forty
15:45:04.9 [EGPWS] Thirty
15:45:05.7 [EGPWS] Twenty
15:45:08.2 [EGPWS] FIVE
15:45:11.7 [CAM] (Sound similar touchdown & landing gear compression) T=0
15:45:12.1 [CAM] (sound similar throttle movement full reverse position) T + .4 sec
15:45:13.4 [SIC] Spoiler T + 1.7
15:45:17.0 [SIC] rev(ersers) green T + 5.3
15:45:18.9 [SIC] manual braking T + 7.2
15:45:20.4 [SIC] decal T + 8.7
15:45:21.8 [CAM] sounds of engine spool up T + 10.1
15:45:27.2 [SIC] SEVENTY Knots T + 15.5
15:45:31.5 [CAM] (sounds of single chime) T + 19.8
15:45:34.2 [CAM] (sound of thump/clunk) T + 22.5
There are a few aspects that we can gather :
- The touch-down phase
The automated Rad Alt calls between 40 ft and 20 ft give us a vertical speed of 800 ft/min, which is about normal for the visual glide slope of 5.4° for Runway 02... Landing seems routine.
The same calculations applied to the times elapsed between 20 ft and 5 ft give a vertical speed of 360 ft/min, revealing the begining of the flare.
The average vertical speed between the 5ft call and the touch-down shows an overcooking of the flare...i.e a short floating bit over the runway. Not really a big deal but worth some 260 meters that will, be lacking later.
- RWA deceleration theory :
Suppose that the CVR recording was indistinct, and the transcript is therefore inaccurate? And that what the F/O actually called ('decal' in the transcript) was 'NO DECEL'?
and
the ground spoilers did not in fact deploy.
So let's see :
The aircraft was not decelerating until the supposed "no decel" call and we take the deceleration from the time the sound of spooling-up engines is recorded, right. So from T+10.1 to T+15.5 (the 70 kt call,IAS corrected with 10 kt tailwind), 5.4 seconds have elapsed and the speed was brought from 148 kt (76 m/s) to 80 (41 m/s). That makes us a decel of 6.5 m/sē or .65 G...WhoooooAH ! That's some manual braking on a wet runway !
With this number, they woud have come to a complete stop in a mere 11.7 seconds with a stopping distance of 445 m.
So, really what are we talking about : an airplane with some faults on its major components stopping on the runway. Call the mods ! This is ridiculous !
- The spoilers case
In light of the fact that only one out of ten spoiler panels was deployed when the aeroplane crashed, and the further information that the First Officer made the spoiler call on the basis of an instrument reading and not from direct observation, we now have to add in another possibility.
Namely that the ground spoilers did not in fact deploy.
Basing the spoiler-not-deployed theory on the basis of one picture is, to say the least, very bold.
For the spoilers to operate, we need :
a/-Electrical power
b/-Three spoiler/elevator computers, independentfrom one another
c/-Hydraulic power from three different systems powering a servo-jack for each panel
d/-An arming lever, with only an up/down position
e/-A logic.
Knowing also that a hydraulic failure will lock the relevant panel in place, tell me of all the other possibilities that brought that configuration after the crash. Can you ?
Fortunately, we have a few professionals, among whom :
5071h
I understand that Airbus has informed operators that there were no malfunctions identified on the FDR; anyone able to confirm this?
When looking for similarities, I note that in accident scenarios humans appear to fail more often than do aircraft systems;- mis-selection, incorrect procedure, mis-assessment of the situation, inappropriate decision, failure to understand implications, etc. Many, if not all of these appear to be associated with this and recent overrun accidents, thus the human and associated factors (met, runway surface, distance, planning) might be chosen as the main theme of the investigation as opposed to the aircraft.
bubbers44
I still think landing downhill on a wet 5400 ft runway with a cliff dropping 70 ft and landing a tad long in an A320 with a 10 knot tailwind left little brake failure problems to finish the accident. Why did they do that?
bsieker
This landing was not an emergency landing.
I leave that as the final word.