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We had one but the server decided to throw it away as a gesture of respect.

Anyway, that Sao Paulo mess. The blame game's in full swing already.

As an aside, my local airport tried to continue to operate a resurfaced runway with inadequate grooving this year and airlines refused to land on it until it was closed and rectified. I think someone was fired eventually that time.

So - the plane in Sao Paulo, they're now claiming, was going far too fast on landing, couldn't get a grip and was in the process of accelerating for a fly-round when the gas station got in its way. Nothing to do with the runway any of that, you'll notice.

The small print is that "A day before Tuesday's accident, two other smaller planes skidded off".

Of course if it's true that the pilot tried to put it down at three times the usual speed ("video footage is said to show the final moments of the TAM flight and another similar plane which had arrived earlier. It shows the first aircraft apparently taking 11 seconds to travel along the runway, while the plane that crashed covers the same distance in three.") and changed his mind about braking then I don't imagine the runway resurfacing had a lot to do with what happened. It would be an odd pilot who was quite so reckless though on a rainy day, don't you think?

I'm all for airlines refusing to land any planes at all rather than giving it their best effort, myself.

There's no indication from reading the flight data / cockpit voice recorders yet, that's where the details crawl out of the woodwork and surprise everyone. I have a hard time believing the plane was trying to take off again and go round for another try, or that it came off the runway at an angle because it skidded. Neither does the switched-off thruster reverser come into it as a cause. I think there's a hardware failure at the back of what happened - an engine fired up to full thrust perhaps, or a wheel assembly getting so mashed up that the brakes failed entirely. It must have been going at a fair lick to jump the road at the end of the runway rather than just toppling into it.

spot;664717 wrote: I think there's a hardware failure at the back of what happened - an engine fired up to full thrust perhaps


Ah. I wrote "hardware failure" thinking the computer controls would stop a pilot from having one engine pushing while the other engine's in thrust reverse but I may have been wrong. The brakes have little effect in such circumstances since the computer disobligingly refuses to deploy the spoilers while all that confusion is going on, and the plane tends to pull to one side rather in the way this one did. Not a thing to do on a short wet runway, really.

Here's one that happened to the same model three years ago, again with thrust reverse disabled on one engine which was subsequently not powered down to idle when the other was reversed:At 1959:32, the autothrottle disconnected, number one thrust reverser deployed, number two thrust reverser not deployed.

At 1959:37 CM-1 called out “no brake”, until 1959:50, CM-1 called “no brake” five times. In the meantime, air speed 112 knots, ground speed 109 knots.

At 1959:42, the left/right brake pedal angle positioned at 28/46 degrees. After eight seconds until its full stop, all of the brake pedals angle were positioning between 62 degrees to 80 degrees.

The ground spoilers did not extend.

http://www.asc.gov.tw/acd_files/189-c1contupload.pdf

Scrat;668936 wrote: I heard they fired the Sec of Defence in Brazil today because of this. Something about the runway not being long enough.


If the runway were not long enough it's odd that thousands of other planes had used it before this one. There's no fixed safe length for a runway.

Sometimes there's a single cause of a crash, like a non-resident flock of big birds flying into both engines during takeoff on a two-engine plane. Mostly there's a series of coincident events, the absence of any one of which would have saved the day. If it had been dry, or if the runway had been longer, or if the thrust reverser hadn't been out of commission, or if the A320 throttle control protocol prevented one engine pushing while the other had reverse thrust selected - it's usually a litany of ifs.

Brazilian air safety has fallen into a poor state over a period of time. The guy who's been fired was in office when the latest series of bad events happened. Their President came out with some drivel about selecting a replacement airport site within 90 days and presumably hopes that the sacrificial firing will take the pressure off his administration.