Right away, I'll say that I don't have much factual to add about the overrun. The left-veering track and the INOP #2 reverser have been noted. Much else will have to wait for the FDR and CVR. I hope the details will be made public. [Edit on 13 August: as indeed they now have been].
However, I was interviewed by email for Folhas de Sao Paolo at the weekend, through a reporter of theirs at Harvard who had attempted to read a scientific paper I published a decade ago about the A320 braking logic. It is not clear to me that the people in Sao Paolo actually understood all of what I said, so I would be grateful for feedback as to what actually appeared in Folhas.
As far as I know, spoilers and thrust reverse on landing on the A320 are controlled by the same state logic (they certainly were on the machine in the 1993 Lufthansa Warsaw overrun, but the logic has changed since then). So either one has spoilers *and* reverse, or neither. So if Danny thinks that port reverse is apparent, he must also conclude either that spoilers are activated or that there is an apparent technical fault [Edit on 13 August: this is faulty logic on my part. As we now know, TL#2 was not brought to idle.]
Aviation Safety Network, which one may regard as an authoritative source, lists 17 hull loss accidents to the A320 since service intro. Of these, five are flight-unrelated (three burnt in a hangar fire in Brussels, one a refueling accident when the truck drove away without disconnecting the hose, one with famous photos where maintenance people taxied the aircraft into the terminal at La Guardia), and one, at Tainan to a Transasia aircraft [Edit on 13 August: the report recently referenced here concerned the Transasi Taipei overrun, which was not a hull loss], concerned hitting a ground vehicle on the runway on landing (so obviously type-unrelated). This leaves 11 hull loss occurrences which are flight-related. Of these, four are runway-overrun accidents (I include going off the side as overrun): 1993 Lufthansa Warsaw, 1998 Philippine Airlines Bacolod, 2002 America West Phoenix, and 2007 TAM Sao Paolo Congonhas. However, they don't list 1998 Air UK Leisure at Ibiza [Edit to reflect the correct airline to which this occurred] which report is to be found on the compendium on my WWW site.
Looking at the four listed by ASN, one notes thrust-reverser issues.
At Bacolod as at Phoenix, the aircraft had reverse thrust on one, and forward thrust on the other, engine at some point in the landing role [Edit on 13 August: the Bacolod report may be found in the Compendium on our WWW site now; the very short Phoenix report on the NTSB WWW site]. At Phoenix, one reverser was known INOP, as at Congonhas. According to ASN and the short NTSB report, the CAP put both throttles into reverse, but then took the #1 out of reverse, and apparently moved it inadvertently to the TOGA position. He lost directional control. At Bacolod, "it appeared" that #1 remained on forward thrust after touchdown, but #2 went into reverse. No ground spoilers because #1 wasn't brought back to idle. PF set #2 to forward thrust to regain directional control and "went through the fence".
At Warsaw, reverse thrust/spoilers did not activate immediately because the squat switches on the main gear were not compressed. There was some evidence also of rubber reversion. There is some similarity to the Air France A340 overrun at Toronto. Both those accidents occurred on runways with a notoriously short overrun area, as at Congonhas.
EMAS is described in US FAA AC 150/5220-22A, dated 30 September, 2005. In response to earlier suggestions on this thread about EMAS, my guess from looking at the photos of the departure end of 35L is that there wouldn't be enough room for one. One has to set them back some way from the threshold, to allow for the possibility of someone landing short - you really don't want to touch down on an EMAS!
PBL
Last edited by PBL; 13th Aug 2007 at 11:05.
Reason: To remedy an inaccuracy pointed out by armchairpilot94116