Interesting reading for A330 pilots
Thread Starter
Join Date: Jan 2006
Location: Between a rock and a hard place
Posts: 1,234
Likes: 0
Received 0 Likes
on
0 Posts
Taiwan's CAA reported the root cause of the occurrence is still under investigation and advises all A330 operators to take countermeasures:
- prior to dispatch consider possible deceleration deficiencies with the conditions mentioned above on wet runways.
- required landing distance shall be predetermined for a wet runway, if the distance is a concern consider an alternate aerodrome
- operators should enhance crew awareness of wet runway operations, if automatic braking is out of function promptly change to the alternate system or apply manual braking
Very helpful advice...
- prior to dispatch consider possible deceleration deficiencies with the conditions mentioned above on wet runways.
- required landing distance shall be predetermined for a wet runway, if the distance is a concern consider an alternate aerodrome
- operators should enhance crew awareness of wet runway operations, if automatic braking is out of function promptly change to the alternate system or apply manual braking
Very helpful advice...
Psychophysiological entity
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 83
Posts: 3,206
Likes: 0
Received 0 Likes
on
0 Posts
Gasp. The computers were like folk rejecting a hot potato.
I get the feeling there wasn't a lot of ABS-ing going on. That was a loooong time with very low - g forces.
I assume that high hydraulic pressure recorded latterly doesn't actually reach the brake hubs? IIRC, ~ 2,600psi.
I get the feeling there wasn't a lot of ABS-ing going on. That was a loooong time with very low - g forces.
I assume that high hydraulic pressure recorded latterly doesn't actually reach the brake hubs? IIRC, ~ 2,600psi.
The crew were given a 
sandwich at a very bad time. It look's like good CRM and prompt crew action prevented an over run for what should have been an impossible fail mode.
Kind of makes you wonder how this would have gone in a "single pilot" version of the aircraft........
sandwich at a very bad time. It look's like good CRM and prompt crew action prevented an over run for what should have been an impossible fail mode.Kind of makes you wonder how this would have gone in a "single pilot" version of the aircraft........
Join Date: Jun 2002
Location: Southern Europe
Posts: 317
Likes: 0
Received 0 Likes
on
0 Posts
After that, the nose gear flipped between air mode and ground mode for nearly 7 seconds.
Just can't see which one is it ...
Psychophysiological entity
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 83
Posts: 3,206
Likes: 0
Received 0 Likes
on
0 Posts
Also, I'm not at all sure this was prompt action. As a dinosaur, I'm very hesitant to criticise younger crews that know so much more, but that prolonged low negative g was making me ache as I counted the seconds.
I recall getting into the habit of testing the brakes while the kinetic energy was still high. Hardly enough for the passengers to feel, but that short moment was very comforting and all-telling. I imagine these days the system would tell on me for non SOP actions.
I recall getting into the habit of testing the brakes while the kinetic energy was still high. Hardly enough for the passengers to feel, but that short moment was very comforting and all-telling. I imagine these days the system would tell on me for non SOP actions.
Join Date: Oct 2019
Location: SW1A 2AA
Posts: 204
Likes: 0
Received 0 Likes
on
0 Posts
zerograv
Seem to recall some strange logic on the 330 that gave a better stopping distance once the nose strut was compressed when using max manual braking. One of our techies found it and it was his pet "how clever am I" subjects.
Seem to recall some strange logic on the 330 that gave a better stopping distance once the nose strut was compressed when using max manual braking. One of our techies found it and it was his pet "how clever am I" subjects.
I hope the people at Airbus are taking a long hard at what caused the computers to all fail at pretty much the same time - that's probably not a coincidence - there is some unknown common failure going on.
We had an issue several years ago with the CF6-80C2 FADEC. There was an in-flight shutdown - and when I looked at the data it very much appeared that both FADEC channel CPUs failed at the same time (or within one second, since that was the data recorder frequency). Now, while that is theoretically possible, the odds are astronomical - in fact our engine controls Tech Fellow went so far as to say it was impossible. But with nothing else to go on I figured it was a freak occurrence. But then there were several other shutdowns with the same symptoms (IIRC we ended up with 7 total shutdowns due to that cause). GE was finally able to track it down - it was an Electro Magnetic Interference (EMI) effect when continuous ignition was commanded on. Turns out there had been several hardware changes and a software change over the previous 10 years that combined to give the susceptibility
.
The real concern was it was a potential common cause failure since continuous ignition is commanded when the flaps are lowered during approach. Fortunately the actual probability of Con Ignition 'ON' causing a shutdown was quite low so the odds of a multiple engine event were in the 10-9/flight range, but it was still worrisome (and you know what they say about statistics). The FAA quickly issue an AD that dictated 'depairing' of suspect FADECs (i.e. you could only have one FADEC with that particular combination of software and hardware configuration per aircraft), and I slept better after we got a fix certified and retrofit into the fleet.
We had an issue several years ago with the CF6-80C2 FADEC. There was an in-flight shutdown - and when I looked at the data it very much appeared that both FADEC channel CPUs failed at the same time (or within one second, since that was the data recorder frequency). Now, while that is theoretically possible, the odds are astronomical - in fact our engine controls Tech Fellow went so far as to say it was impossible. But with nothing else to go on I figured it was a freak occurrence. But then there were several other shutdowns with the same symptoms (IIRC we ended up with 7 total shutdowns due to that cause). GE was finally able to track it down - it was an Electro Magnetic Interference (EMI) effect when continuous ignition was commanded on. Turns out there had been several hardware changes and a software change over the previous 10 years that combined to give the susceptibility
.The real concern was it was a potential common cause failure since continuous ignition is commanded when the flaps are lowered during approach. Fortunately the actual probability of Con Ignition 'ON' causing a shutdown was quite low so the odds of a multiple engine event were in the 10-9/flight range, but it was still worrisome (and you know what they say about statistics
). The FAA quickly issue an AD that dictated 'depairing' of suspect FADECs (i.e. you could only have one FADEC with that particular combination of software and hardware configuration per aircraft), and I slept better after we got a fix certified and retrofit into the fleet.
Join Date: Sep 1999
Location: United Kingdom
Posts: 929
Likes: 0
Received 0 Likes
on
0 Posts
Quite a while back. We lost 5 of the 6 screens whilst climbing out of Tenerife. Only for 15 seconds or so. I flew the same aircraft a few days later & had a look at the relevant tech log page. Defect was cleared as “Not Possible” I suspect that their is a bit of a mind set when it comes to these very very very rare events. Glad the FADEC issue was followed up with more enthusiasm.
