PIA A320 Crash Karachi
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Last edited by MPN11; 4th Jul 2020 at 11:17. Reason: distances
Only half a speed-brake
Most likely not. Given the inherent and regulatory margins, over-running the runway with a modern-day airliner requires substantial effort.
History suggests these usual suspects:
- runway is short (less than 2000 m)
- runway is slippery
- the braking effectiveness of the aircraft is significantly reduced
- touchdown is achieved well further than 2x the normal point (not to be confused with runway "touchdown zone")
- significant extra speed is carried for the landing, 20% or more.
Evidence shows satisfying 2 of the above is not enough to mowe the lawn. 3 will do, 50:50 and with 4 all you can do is wait for the final investigation report.
History suggests these usual suspects:
- runway is short (less than 2000 m)
- runway is slippery
- the braking effectiveness of the aircraft is significantly reduced
- touchdown is achieved well further than 2x the normal point (not to be confused with runway "touchdown zone")
- significant extra speed is carried for the landing, 20% or more.
Evidence shows satisfying 2 of the above is not enough to mowe the lawn. 3 will do, 50:50 and with 4 all you can do is wait for the final investigation report.
Last edited by FlightDetent; 4th Jul 2020 at 14:02.
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Thanks. I've reviewed my guesstimate and edited my post. That aircraft was certainly reluctant to stop flying, though.
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“EMER CANC Button When pushed:
Warnings - Present aural warning is cancelled. MASTER WARN switches extinguish. ECAM message display is not affected.”
So yes, I would say it does cancel the CRC, however is there any reset built in to the system where the warning will be retriggered?
Landing with abnormal gear has one accomplish this: “GPWS SYS switch - Off” so if there is a retrigger, switching the GPWS off would prevent another CRC. Vilas?
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Thanks for the replies. While I wasn't fully aware of the term 'Normalization of Deviance', holistically, one can see it when comparing what is generally acceptable in different parts of the world. That's concerning, especially when so many lives are at stake.
It'd be interesting to look back through PIA FR24 data to see how many times unstabilized approaches were attempted and completed without such dire consequences. I think someone suggested looking through available information earlier in the thread but I am not sure if anything ever came out of it.
It'd be interesting to look back through PIA FR24 data to see how many times unstabilized approaches were attempted and completed without such dire consequences. I think someone suggested looking through available information earlier in the thread but I am not sure if anything ever came out of it.
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If you EMER CANCEL any warning/caution it will be silent this kind of warning/caution for the rest of the flight. You will get a white info-text in the EWD what kind of warnings/cautions are silent. If you press and hold the clear button for more then 5 seconds, all silent warnings are cleared and everything is "normal" again.
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When high and fast first get the speed right that reduces closing in speed. At 10.7nm. 7000ft. 245kts had they leveled with speed brakes and gear configured to Vapp they would have had six miles to touchdown and 7000ft to loose. Easily done(since they were bent upon doing).
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Landing with abnormal gear has one accomplish this: “GPWS SYS switch - Off” so if there is a retrigger, switching the GPWS off would prevent another CRC. Vilas?
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I have to wonder... if after another incident directly attributable to gross pilot error, and/or some impossible to reasonably foresee design "flaw" (NOT saying PIA 8303 is such, yet) inflamed public pressure (see now fully systemic media hysteria) on regulators/politicians leads to manufacturers/lessors being barred from supplying aircraft to ... erm, non-compliant airlines, and the ensuing somewhat justifiable cries of the r word when most of the world's airlines are forced to fly TU154b's!
Commercial transport, I would argue, has entered an entirely futile and moribund phase of existence where any and all incidents are just more nails in the coffin, unless some broadly acceptable new way forward is established.
How exactly does one reintroduce acceptable risk in our increasingly and relentlessly risk-averse society? My feeling is we have reached the apex of airliner design and automation and Artificial Incompetence is simply not a path forward for the foreseeable future.
Don't even ask me what that way forward is! I'm just a lowly PPL that becomes heavily task-saturated whilst walking and chewing gum at the same time. My speculation may be a tad hyperbolic, but some variant of the theme could/should prove an entirely reasonable subject to ponder.
Commercial transport, I would argue, has entered an entirely futile and moribund phase of existence where any and all incidents are just more nails in the coffin, unless some broadly acceptable new way forward is established.
How exactly does one reintroduce acceptable risk in our increasingly and relentlessly risk-averse society? My feeling is we have reached the apex of airliner design and automation and Artificial Incompetence is simply not a path forward for the foreseeable future.
Don't even ask me what that way forward is! I'm just a lowly PPL that becomes heavily task-saturated whilst walking and chewing gum at the same time. My speculation may be a tad hyperbolic, but some variant of the theme could/should prove an entirely reasonable subject to ponder.
I'm late to the party. I assume this has been posted. https://aviation-safety.net/database...?id=20200522-0
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They had both Gens offline, no APU Gen and the RAT deployed, so the aircraft is now operating in emergency configuration ...
Question to those current: I would imagine this put us into direct law, but are any protections still active ?
Question to those current: I would imagine this put us into direct law, but are any protections still active ?
Last edited by Teddy Robinson; 5th Jul 2020 at 10:19. Reason: punctuation
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On the 330 in such configuration (ELEC EMER) you get into alternate law. That means you have no more ‘‘hard’’ protection preventing you to escape from certified flight domain. You can physically stall, nothing will prevent you from this, except an aural warning ‘‘STALL STALL’’. I don’t know whether it’s different with the 320..
Hi vilas - not current, but if I remember, in the Emer Electrical Config the a/c is in Alt.Law as stated, but all protections are lost and when the gear goes down the aircraft reverts to Direct Law?....
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So the final descent could not have been flown at alpha max, as there were zero protections if I read this correctly.
Only half a speed-brake
No FDR post the dual engine failure suggests no APU. Then irrespective of any good residual hydraulic pressure from the wind milling engines (well, loss of oil...knock, knock) the configuration would be Emerg ELEC and that is DCT law after gear down, in the book.
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Seems like they: a) forgot to turn on the APU by instinct after recognition of the second engine failure; b) didn’t remember/have time to apply the “Emer Landing (all eng fail)” procedure; or c) they did start it, but there wasn’t enough time for the APU to spool up and get the generator online. The last one I hardly doubt it, because I remember seeing the APU intake flap closed in the first photos we saw of the aircraft, right before it crashed.
It would/will be very interesting to see how they managed the dual engine failure, after all the mess that happened right before...
It would/will be very interesting to see how they managed the dual engine failure, after all the mess that happened right before...