Iced AoA sensors send A321 into deep dive
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Anybody have a clue as to why it would take those experienced Lufty A321 pilots (after pressing those easy-to-reach overhead "QEB-48" buttons) 4000 feet of altitude loss to recover?
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Hey, it's only been 27 years since Airbuses started to pitch down on their own, hurting or killing people in the process, for whatever reason fits HAL.
Pilots still fly them, passenger still board, my guess is Airbus won't fix it anytime soon, buses will keep divin'.
Pilots still fly them, passenger still board, my guess is Airbus won't fix it anytime soon, buses will keep divin'.
Hardly Never Not Unwilling
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TOGA is always TOGA; idle is always idle.
At the first sign of anomaly that is taking away your flight control, disconnect the autopilot, auto thrust, and turn off the flight directors. Set 85-90% N1 and recover level flight, crosschecked against standby instruments.
I've been flying for a living for more than 40 years, the last 10 in A-320's. The above is my basic boldface for just about everything that can come up on the Bus. That is "flying the airplane".
When the dust settles you can get out the QRH, talk to each other, and figure it all out.
For God's sake, though, just look around if you find yourself climbing or descending abruptly for no good reason. Pickle everything off and level the flight with a reasonable power setting.
At the first sign of anomaly that is taking away your flight control, disconnect the autopilot, auto thrust, and turn off the flight directors. Set 85-90% N1 and recover level flight, crosschecked against standby instruments.
I've been flying for a living for more than 40 years, the last 10 in A-320's. The above is my basic boldface for just about everything that can come up on the Bus. That is "flying the airplane".
When the dust settles you can get out the QRH, talk to each other, and figure it all out.
For God's sake, though, just look around if you find yourself climbing or descending abruptly for no good reason. Pickle everything off and level the flight with a reasonable power setting.
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But BenT* if the side sticks ain't working you can't set a sensible attitude until you degrade the FBW, to a point you can regain control, even if that means "manual pitch trim only" That takes diagnosis & time. Hats off to the LH crew. ( yes I know in this case, they only needed to degrade to alternate law)
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Most (yes I know) of these events happen at cruise level.
That gives you enough time to sort it out. Even AF447 decending at 10,000 fpm had 4 minutes to get organised.
4 minutes is a long time. In most cases you will have a lot longer so no need to panic, just sort it out logically.
That gives you enough time to sort it out. Even AF447 decending at 10,000 fpm had 4 minutes to get organised.
4 minutes is a long time. In most cases you will have a lot longer so no need to panic, just sort it out logically.
Last edited by The Ancient Geek; 22nd Mar 2015 at 21:25. Reason: Fix error
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As others have pointed out in Alpha protection you have temporarily handed over control to the aircraft and until you exit Alpha Protection that's the way it stays. It matters not what you do with the T/Ls or sidestick as the nose down or nose up demand cannot be overridden in Normal Law! Once clear of Alpha and the ensuing TOGA Lock, you have full control back. If you suspect unwanted Alpha activation, that's when the AD must be followed and switch off 2 ADRs which takes no time and degrades you to Alternate Law and gives full control but no A/P or A/THR. Landing takes place in Direct Law once gear extended.
Benthere,
As someone who claims to have flown the Bus for 10 years, it sounds like you don't understand the fundamental laws which I find frightening!
Benthere,
As someone who claims to have flown the Bus for 10 years, it sounds like you don't understand the fundamental laws which I find frightening!
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I's you who are frightening me, with all due respect.
It should be instinctual to any Airbus pilot to disconnect the automation when any unanticipated thrust/vector surprise occurs, stabilize the aircraft, then deal with the situation. If the protections are interfering with that, then you address changing the law.
The FMA and PFD will tell you what lock you are in, if you haven't already resolved the problem, and you then mitigate that, switching off two ADRs if needed.
My whole point is to not sit there and wonder what's going on. Getting the stick and rudder back in your hands is required in all such circumstances. Punching off the automation may not be all that's required, but it is the first step. If, after punching it off, you still don't have control, the two ADR PBs are the next step, but only after you determine the system inputs to normal law are erroneous.
It should be instinctual to any Airbus pilot to disconnect the automation when any unanticipated thrust/vector surprise occurs, stabilize the aircraft, then deal with the situation. If the protections are interfering with that, then you address changing the law.
The FMA and PFD will tell you what lock you are in, if you haven't already resolved the problem, and you then mitigate that, switching off two ADRs if needed.
My whole point is to not sit there and wonder what's going on. Getting the stick and rudder back in your hands is required in all such circumstances. Punching off the automation may not be all that's required, but it is the first step. If, after punching it off, you still don't have control, the two ADR PBs are the next step, but only after you determine the system inputs to normal law are erroneous.
For God's sake, though, just look around if you find yourself climbing or descending abruptly for no good reason. Pickle everything off and level the flight with a reasonable power setting.
I must be missing the 'irony'
Anyway it seems like some current Ab Pilots believe you can disconnect all automation by turning off the Autopilot and Autothrust.
But that does not appear to be accurate, unless you're in a Boeing, Douglas, Lockheed, Fokker etc
This crew did a great job managing to correct a machine that makes 'Hal' look well mannered.
Anyway it seems like some current Ab Pilots believe you can disconnect all automation by turning off the Autopilot and Autothrust.
But that does not appear to be accurate, unless you're in a Boeing, Douglas, Lockheed, Fokker etc
This crew did a great job managing to correct a machine that makes 'Hal' look well mannered.
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Stilton, you're right. More specifically, many don't seem to see the distinction between AFS malfunction and FBW malfunction. In the latter, pilots disconnecting the AFS is not going to resolve the issue - the FBW has to be over-ridden in some way, either in methods planned by engineers or other means. And it is this very lack of direct control pilots have when systems fail that convinces so many of terrible design of the Airbus fleet.
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As a C130 Hercules instructor many years ago, one of the duties was to teach in the simulator. The simulator would sometimes a mind of its own and throw the crew (and especially the instructor on a “bar stool”) around in a somewhat disconcerting manner. It was vital for instructors to be able to locate and thump a big coloured “kill everything” button, even in the dark.
I can’t really understand the Airbus system of needing two buttons is not simplified to one DAMN GREAT BIG BUTTON.
I can’t really understand the Airbus system of needing two buttons is not simplified to one DAMN GREAT BIG BUTTON.
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Because this AD is a temporary fix for something that clearly wasn't foreseen by Airbus but it takes no time at all to press these buttons as they are next to one another. In time a permanent fix will be available - hopefully soon. In the meantime life on the Bus will go on as normal for those of us who fly it! 
Whilst we are at it Boeing never foresaw the rudder hardover on the 737 or the other manufacturers of T tail planes suffering deep stalls so let's not get all precious and sanctimonious about this!
On the Airbus, active (not passive) monitoring is the key!
Whilst we are at it Boeing never foresaw the rudder hardover on the 737 or the other manufacturers of T tail planes suffering deep stalls so let's not get all precious and sanctimonious about this!
On the Airbus, active (not passive) monitoring is the key!
No one seems to have mentioned the fact that the THS can be moved manually to control the pitch at all times, even in flight.
The aerodynamic authority of the THS is way in excess of the elevator authority.
This fact was very obvious while conducting Upset Recovery Training in the sim when use of the THS greatly speeds up the recovery action.
Just because it isn't touched after setting the take-off trim after start doesn't mean that it can not be used in flight.
No Airbus manual will say this however.
The aerodynamic authority of the THS is way in excess of the elevator authority.
This fact was very obvious while conducting Upset Recovery Training in the sim when use of the THS greatly speeds up the recovery action.
Just because it isn't touched after setting the take-off trim after start doesn't mean that it can not be used in flight.
No Airbus manual will say this however.
There is something missing in the discussion on the bus flight control system. People keep saying you push two buttons and you have full control. That's not actually the case. Following the new procedure downgrades you from normal law to alternate law. It does not remove the computers from the loop like the switch in a 787.
So, could someone in the know explain us poor non-buss drivers what would happen if an A-320 took off, say on a freezing cold day, with two AOA sensors stuck at values beyond stall AOA ?