British Airways A350 Hard Landing at Tel Aviv
Join Date: Oct 2008
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Flare Law
330 and 350 FCOMs present the same picture of Flare Law using different wording save the 350 not mentioning the slight pitch down elevator order at 50ft.
The 330 generates Reactive Windshear Warnings based on predicted AOA excursions (couldn't find it mentioned in 350 FCOM). I am aware that smooth stick inputs to recover an increasing descent rate can help prevent warnings being generated but I wouldn't have thought unloading initially to be warranted. But perhaps that's what transpired....
The 330 generates Reactive Windshear Warnings based on predicted AOA excursions (couldn't find it mentioned in 350 FCOM). I am aware that smooth stick inputs to recover an increasing descent rate can help prevent warnings being generated but I wouldn't have thought unloading initially to be warranted. But perhaps that's what transpired....
Basically the Airbus FBW auto-thrust and G/S mini combination works extremely well. There are a couple of provisos to that statement: One is that the aircraft we fly can be heavier than we think from the load sheet. +2 tonnes is common, I did see nearly +4 tonnes once! So beware that Vapp might not be correct for your weight. Always check that Vapp bug is at least Vls+5kts, and adjust if necessary.
If you are in an A330, its auto-thrust is "lazy". On certain days it might let the speed dribble down to 3-4kts below bug, and this is something to be avoided, otherwise a heavy landing can result. My advice is to do something about that. On approach, if LDA is not limiting, you could adjust Vapp to be Vls+6 or Vls+7. Or simply use phase advance or go manual thrust.
Don't be afraid of manual thrust - Airbus say to take over if the system response is unsatisfactory - just make sure you understand what will happen when you use it, and practice using it on easy good weather days, so you are confident.
Once you are over the threshold, accept the speed you have and concentrate on the landing. Having said that, if speed is below Vapp-5kts, a baulked landing would probably be safer, unless you are totally confident about using manual thrust.
I am not a trainer, nor an authority, just what works for me. I have not flown A350 or A340.
Enjoy !
Join Date: Oct 2003
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Good summary, Uplinker and I agree a good discussion I have learnt a lot.
i would disagree with this however:
...since Airbus has recommended this not be used. My airline banned it about ten years ago, never knew why until this thread explained the reason.
Agree with everything else you said. I treat A330 AT with suspicion particularly on short finals in any sort of gusty conditions. My rule of thumb is to add a few knots in these cases
i would disagree with this however:
...since Airbus has recommended this not be used. My airline banned it about ten years ago, never knew why until this thread explained the reason.
Agree with everything else you said. I treat A330 AT with suspicion particularly on short finals in any sort of gusty conditions. My rule of thumb is to add a few knots in these cases
If you find the AutoThrust is "lazy" on an approach you will probably find that the conditions are smooth and your sidestick inputs are also "slow" and smooth.
To "wake" the AutoThrust up and have it respond quickly, simple make some rapid (tiny) sidestick pitch inputs.
The way it was explained to me was that rapid sidestick pitch inputs cause a phase/gain shift in the AutoThrust response. This in turn makes thrust change response time quicker and magnitude larger.
Don't be over-smooth, fly it like a Navy carrier approach, hold the glide slope as accurately as possible with lots of tiny and timely sidestick pitch inputs.
You'll have that sucker eating out of your hand in no time!
To "wake" the AutoThrust up and have it respond quickly, simple make some rapid (tiny) sidestick pitch inputs.
The way it was explained to me was that rapid sidestick pitch inputs cause a phase/gain shift in the AutoThrust response. This in turn makes thrust change response time quicker and magnitude larger.
Don't be over-smooth, fly it like a Navy carrier approach, hold the glide slope as accurately as possible with lots of tiny and timely sidestick pitch inputs.
You'll have that sucker eating out of your hand in no time!
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Exactly. Needlessly push and pull on the side stick to make it really fly. The thrust already goes up and down on it's own so adding in sidestick inputs might bring everything into harmony. Besides, being smooth is overrated. (sarcasm).
Surprisingly enough the AB products fly like regular airplanes with the autothrust/throttles off.
A 5 kt speed loss is being blamed for a hard landing?? Vicious winds, we should be damaging airplanes every day across the world.
Surprisingly enough the AB products fly like regular airplanes with the autothrust/throttles off.
A 5 kt speed loss is being blamed for a hard landing?? Vicious winds, we should be damaging airplanes every day across the world.
It seems to be an A330 problem when there is no significant wind, so no G/S mini addition, but a hot day with thermals on finals. Not to me - I have hammered-in the occasional A321 due to stupidity on my part, but not an A330 (yet).
Only half a speed-brake
The standard bugged speed is Vref +5 kt buffer for A/THR deficiencies.
If eating into this margin and arriving at Vref, +1/+2 i.e. just above the normal and certified approach speed results in a slammer, it sounds a bit of an incomplete story to an outsider.
While you are not the first one to say so, I wonder what are the blanks that need filling.
THS freeze at 100?
If eating into this margin and arriving at Vref, +1/+2 i.e. just above the normal and certified approach speed results in a slammer, it sounds a bit of an incomplete story to an outsider.
While you are not the first one to say so, I wonder what are the blanks that need filling.
THS freeze at 100?
Last edited by FlightDetent; 1st Feb 2020 at 19:30.
