Air France crash at YYZ (Merged)
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From page 28:-
"If the rain had just moved in, the runway surface could well have been more oily than wet.
The top part of pavement is full of petroleum-based products, mostly microscopic bits of tyres. When it first rains after a dry spell, those oily bits of petroleum float on the surface of the just-fallen rain, and that is when a paved surface is the most slippery. This is particularly true on those areas where the tyres are accelerating, decelerating, or turning (because thet's where they shed the most rubber). After it has been raining for a few minutes, the water/oil ratio grows large enough to eliminate the oil surface, and it's just a question of a wet surface."
The above situation is 'normal' (given the conditions) and shouldn't be a surprise to any transport driver. What isn't normal is a sudden reversal of wind direction or a sudden cloudburst. An earlier posting by a jockey described extra flaps and a 'determined' touch-down, which sounded good initiative (and common sense). Maybe a combination of that jockey's technique and a better touch-down location towards the runway threshold would have saved the aircraft, though there is still the combination of possible deep water causing aquaplaning (on a non-grooved surface) and the aberration whereby aerodynamic retardation devices might not deploy due to the dynamic parameters of the undercarriage. I believe passengers reported a reduction in deceleration after the initial braking phase.
It might not ALL be driver error . . .
"If the rain had just moved in, the runway surface could well have been more oily than wet.
The top part of pavement is full of petroleum-based products, mostly microscopic bits of tyres. When it first rains after a dry spell, those oily bits of petroleum float on the surface of the just-fallen rain, and that is when a paved surface is the most slippery. This is particularly true on those areas where the tyres are accelerating, decelerating, or turning (because thet's where they shed the most rubber). After it has been raining for a few minutes, the water/oil ratio grows large enough to eliminate the oil surface, and it's just a question of a wet surface."
The above situation is 'normal' (given the conditions) and shouldn't be a surprise to any transport driver. What isn't normal is a sudden reversal of wind direction or a sudden cloudburst. An earlier posting by a jockey described extra flaps and a 'determined' touch-down, which sounded good initiative (and common sense). Maybe a combination of that jockey's technique and a better touch-down location towards the runway threshold would have saved the aircraft, though there is still the combination of possible deep water causing aquaplaning (on a non-grooved surface) and the aberration whereby aerodynamic retardation devices might not deploy due to the dynamic parameters of the undercarriage. I believe passengers reported a reduction in deceleration after the initial braking phase.
It might not ALL be driver error . . .
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What isn't normal is a sudden reversal of wind direction or a sudden cloudburst.
Actually if you make an approach to an airport during a thunderstorm, such a situation is not unexpected.
Actually if you make an approach to an airport during a thunderstorm, such a situation is not unexpected.
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Pprune forums, like events/mistakes discussed over a pint of beer at the bar have become a useful aid to flight safety. We learn from the experience of others and try not to go down the same road of no return.
Our working environment as professional pilots - the atmosphere -is an ever changing one. No two clouds produce the same amount of turbulence. No two approaches will experience the same amounts of wind shift,shear etc.
Reliance on reported met conditions during the approach in order to predict a successful outcome are the norm but....a recent NTSB report expressed amazement at the number of flights continuing to approach and land at a large US airfield in close proximity to large, active CB cells.
Just because the aircraft ahead manages to land we predict that we will be able to do the same.
When the aircraft ahead experiences severe windshear and performs a go around, or crashes....then we predict the unsuccessful outcome and discontinue the approach.
The question....should we have ever been on the approach at all.
The answer....well, nobody has gone around yet!
..... this aircraft is not full, so will be able to successfully go around at any point in the approach with good performance margins!
......I know storms of this size never produce microbursts!
......Company fuel policy put me in this low fuel situation!
...... Jesus...we are so tired, having operated 1 longhaul and 2 shorthaul sectors in one 22 hour duty day, with new f/o and one cruise relief co/pilot, with no adequate inflight rest facility!(Italian operator...God-ENAC help them)... a go-around would be more dangerous than to continue
.....The CEO sacked the last captain that diverted.( Italian operator).
...... I NEVER go-around!!!!
Which one of the above has been your motive for continuing in the past with less than CAVOK!
Let us ALL learn from the experience of others and try to keep ourselves out of Pprune.
P.S. I personally spoke with the Cuban authority about the rubber deposits on the threshold of runway 06 at Havana. In wet conditions the touchdown area is like a skating rink. Be warned that your performance tables would not help you on a reject at max RTOW, on runway 24, in slick conditions. How many other runways around the world suffer the same. Beware predictions based on assumed conditions!!!!!
Our working environment as professional pilots - the atmosphere -is an ever changing one. No two clouds produce the same amount of turbulence. No two approaches will experience the same amounts of wind shift,shear etc.
Reliance on reported met conditions during the approach in order to predict a successful outcome are the norm but....a recent NTSB report expressed amazement at the number of flights continuing to approach and land at a large US airfield in close proximity to large, active CB cells.
Just because the aircraft ahead manages to land we predict that we will be able to do the same.
When the aircraft ahead experiences severe windshear and performs a go around, or crashes....then we predict the unsuccessful outcome and discontinue the approach.
The question....should we have ever been on the approach at all.
The answer....well, nobody has gone around yet!
..... this aircraft is not full, so will be able to successfully go around at any point in the approach with good performance margins!
......I know storms of this size never produce microbursts!
......Company fuel policy put me in this low fuel situation!
...... Jesus...we are so tired, having operated 1 longhaul and 2 shorthaul sectors in one 22 hour duty day, with new f/o and one cruise relief co/pilot, with no adequate inflight rest facility!(Italian operator...God-ENAC help them)... a go-around would be more dangerous than to continue
.....The CEO sacked the last captain that diverted.( Italian operator).
...... I NEVER go-around!!!!
Which one of the above has been your motive for continuing in the past with less than CAVOK!
Let us ALL learn from the experience of others and try to keep ourselves out of Pprune.
P.S. I personally spoke with the Cuban authority about the rubber deposits on the threshold of runway 06 at Havana. In wet conditions the touchdown area is like a skating rink. Be warned that your performance tables would not help you on a reject at max RTOW, on runway 24, in slick conditions. How many other runways around the world suffer the same. Beware predictions based on assumed conditions!!!!!
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Could I add something to your post Graham Curry?
In many parts of this world, the danger of slippery runways is enhanced when the first rain comes at the end of dry season, when dry earth powder deposed in a thin layer on the runway is aggregated and melted to form a film destroying aircraft's braking performance on the whole runway length.
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Great posts alf5071h.
At the risk of simplification, IMHO this accident will find many of its origins in mis-judged visual cues. What little we know about the time history of the speeds on final approach seems to discount violent weather phenomena being a source of difficulty between the R/W THD and TDZ.
Statistically, perhaps the average headwind component I might land with is +10kts? On a 73 series a/c my app Vref 30/40 lies anything between 115 and 140kts. Its not a big jet so the spread is small as the weight change over the course of a flight is small. But its enough to make a difference as to how you put it on the deck.
Our FDR monitoring system gives rise to a monthly report that is issued to the flightdeck community. One month last year, an observation was made in the bulletin on a flight into AMS which showed a flare in excess of 18 secs. I believe the company response was that whilst such antics might reduce the length of your taxi-time to the terminal, it really wasn't SOP and they'd prefer it if, regardless of the length of the runway, pilots did not get into the habit of adjusting their landing technique depending on the length of the runway.
We've all done it - sat in ground effect with a trickle of power on watching the runway go by.
In this instance, you have an a/c flying an approach with a tailwind component approaching 20kts, which means the ground speed is, perhaps, 30kts higher than usual? I'm not sure whether they were at normal weights but for the purposes of the discussion it doesn't really matter...
It looks all wrong out the window and thats without any of the complicating factors that relate to the change in refractive index due to rain on the screen. The pitch attitude is lower, the power is lower, the ROD appears higher, the ground effect is more pronounced.
You check the perceived high ROD the way you normally do in this instance (and you would do because the pitch attitude suggests that you're headed towards the ground faster), and coupled with the more pronounced ground effect (and the fact you may have put some power on because generally you don't like being at idle below 200RA), I can quite conceivably imagine that in an a/c as big as a A340, you could stay in ground effect for 15 secs. You've just upped the lift 30% again...
With the vis down at the level suggested, if you've not shifted your point of reference down the runway, its perhaps only the lights that are going to start giving the game away.
I am lucky that at my home-base the most expeditious exit from the runway favoured by the prevailing winds is 4600ft from the threshold and this requires that, at all but the lightest weights, you have no margin for error if you want to vacate at that taxi-way. It forces you to be disciplined in the last 200ft.
I hope I'm wrong on all of the above.
At the risk of simplification, IMHO this accident will find many of its origins in mis-judged visual cues. What little we know about the time history of the speeds on final approach seems to discount violent weather phenomena being a source of difficulty between the R/W THD and TDZ.
Statistically, perhaps the average headwind component I might land with is +10kts? On a 73 series a/c my app Vref 30/40 lies anything between 115 and 140kts. Its not a big jet so the spread is small as the weight change over the course of a flight is small. But its enough to make a difference as to how you put it on the deck.
Our FDR monitoring system gives rise to a monthly report that is issued to the flightdeck community. One month last year, an observation was made in the bulletin on a flight into AMS which showed a flare in excess of 18 secs. I believe the company response was that whilst such antics might reduce the length of your taxi-time to the terminal, it really wasn't SOP and they'd prefer it if, regardless of the length of the runway, pilots did not get into the habit of adjusting their landing technique depending on the length of the runway.
We've all done it - sat in ground effect with a trickle of power on watching the runway go by.
In this instance, you have an a/c flying an approach with a tailwind component approaching 20kts, which means the ground speed is, perhaps, 30kts higher than usual? I'm not sure whether they were at normal weights but for the purposes of the discussion it doesn't really matter...
It looks all wrong out the window and thats without any of the complicating factors that relate to the change in refractive index due to rain on the screen. The pitch attitude is lower, the power is lower, the ROD appears higher, the ground effect is more pronounced.
You check the perceived high ROD the way you normally do in this instance (and you would do because the pitch attitude suggests that you're headed towards the ground faster), and coupled with the more pronounced ground effect (and the fact you may have put some power on because generally you don't like being at idle below 200RA), I can quite conceivably imagine that in an a/c as big as a A340, you could stay in ground effect for 15 secs. You've just upped the lift 30% again...
With the vis down at the level suggested, if you've not shifted your point of reference down the runway, its perhaps only the lights that are going to start giving the game away.
I am lucky that at my home-base the most expeditious exit from the runway favoured by the prevailing winds is 4600ft from the threshold and this requires that, at all but the lightest weights, you have no margin for error if you want to vacate at that taxi-way. It forces you to be disciplined in the last 200ft.
I hope I'm wrong on all of the above.
Video?
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No technical problem during A340 overrun: Airbus
Airbus says there was no technical problem with the Air France Airbus A340-300 that overran the runway at Toronto Pearson Airport earlier this month.
The pilots flew a manual short-finals to land, disconnecting the auto-thrust and autopilot at a height of about 300ft.
Full flap and slat configuration was selected while the auto-brake was set to ‘MED’ as recommended for landings on short or contaminated runways.
http://www.radarvector.com/2005/08/n...ring-a340.html
The pilots flew a manual short-finals to land, disconnecting the auto-thrust and autopilot at a height of about 300ft.
Full flap and slat configuration was selected while the auto-brake was set to ‘MED’ as recommended for landings on short or contaminated runways.
http://www.radarvector.com/2005/08/n...ring-a340.html
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In this instance, you have an a/c flying an approach with a tailwind component approaching 20kts, which means the ground speed is, perhaps, 30kts higher than usual?
If you're still talking about AF358, from what I understand it's the crosswind which was 20kts, the tailwind was much lower.
Approach speed 143kts, touchdown 148kts.
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There were reports of lightning in the area - and some passengers were saying that the cabin lights went out before a rougher than normal touchdown.
I have not heard anything further on this - but it would seem that the French claim that all systems were go doesn't jive with a dark cabin during a lightning storm.
Anyone know of a follow-up on the lights out claims ?
Good Job AF cabin crew !
I have not heard anything further on this - but it would seem that the French claim that all systems were go doesn't jive with a dark cabin during a lightning storm.
Anyone know of a follow-up on the lights out claims ?
Good Job AF cabin crew !
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Konkordski,
Re tailwind components, my apologies.
Garbage in, garbage out.
Edited to say that in light of NOD's posts further on, I knew I'd seen the 164kts app speed figure somewhere and that therefore my analysis has a little merit.
Re tailwind components, my apologies.
Garbage in, garbage out.
Edited to say that in light of NOD's posts further on, I knew I'd seen the 164kts app speed figure somewhere and that therefore my analysis has a little merit.
Last edited by SR71; 30th Aug 2005 at 19:58.
The Reverend
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it would seem that the French claim that all systems were go doesn't jive with a dark cabin during a lightning storm.
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To try to summarise so far, at the risk of oversimplifying ...
Speed at threshold not absurdly high, altitude at threshold not absurdly high. Touchdown speed not absurdly high, touchdown itself smooth, but 4000 ft from threshold. No attempt made to go-around. Speed at runway end not that absurdly high given touchdown point and wx.
Aircraft technically perfectly ok, spoilers deploy, autobrake activates & reverse selected all work fine.
Highly experienced crew (both captain & FO).
Early on after touchdown full manual braking overrides autobrake, and maintained till the end.
Obviously something caused the 4000-ft loss in runway, but to me this is now almost looking as bearing little relevance.
More interesting has to be what caused the landing to be continued after the long touchdown:
- lack of visual cues ? but rapid autobrake override would seem to deny this.
- "impossible" wx just ahead ? but then what if any "standard" reason to trigger a go-around even earlier eg runway not vacated and/or ATC order had occurred ? Any odd reason like this would then have caused an automatic crash ? KL behind did go-around ok.
There has to be some more compelling reason, otherwise this crash looks like it could well happen again, doesn't it ?
Speed at threshold not absurdly high, altitude at threshold not absurdly high. Touchdown speed not absurdly high, touchdown itself smooth, but 4000 ft from threshold. No attempt made to go-around. Speed at runway end not that absurdly high given touchdown point and wx.
Aircraft technically perfectly ok, spoilers deploy, autobrake activates & reverse selected all work fine.
Highly experienced crew (both captain & FO).
Early on after touchdown full manual braking overrides autobrake, and maintained till the end.
Obviously something caused the 4000-ft loss in runway, but to me this is now almost looking as bearing little relevance.
More interesting has to be what caused the landing to be continued after the long touchdown:
- lack of visual cues ? but rapid autobrake override would seem to deny this.
- "impossible" wx just ahead ? but then what if any "standard" reason to trigger a go-around even earlier eg runway not vacated and/or ATC order had occurred ? Any odd reason like this would then have caused an automatic crash ? KL behind did go-around ok.
There has to be some more compelling reason, otherwise this crash looks like it could well happen again, doesn't it ?
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Rumet,
I agree with your summary.
How did that 4000' disappear?
Yes, a crew “knowledgeable of the locale” probably should have done a go-around.
But the peculiar thing is that on airports with certain topography, some types of glide-slope guidance equipment might suck you in. I wish I knew how the “voting rationale” on an FMS works . . . and when it decides to tell you, “You-take-it”!
If this flight was “slotted in” on a shot-final (5 nM?) . . . and if the altitude was a little too high . . . what does the FMS do when it never receives a “fly-down” from the glide-slope transmissions?
RESA
I agree with your summary.
How did that 4000' disappear?
Yes, a crew “knowledgeable of the locale” probably should have done a go-around.
But the peculiar thing is that on airports with certain topography, some types of glide-slope guidance equipment might suck you in. I wish I knew how the “voting rationale” on an FMS works . . . and when it decides to tell you, “You-take-it”!
If this flight was “slotted in” on a shot-final (5 nM?) . . . and if the altitude was a little too high . . . what does the FMS do when it never receives a “fly-down” from the glide-slope transmissions?
RESA
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From earlier posts:
(posted 8 Aug)
(posted 18 Aug)
There is one point that I have not yet seen mentioned. I do not want to "speculate", and will confine myself to using the TSB and Airbus quotes above and will (bravely) assume the figures they give as facts.
1. Over threshold, IAS roughly correct, but an 18Kt tailwind.
2. Touchdown - IAS of same (correct I assume) magnitude, but now only a 5K tailwind.
3. Poor vis due heavy rain => (significantly) contaminated runway.
Nobody seems to mention the effect of the decreasing tailwind... It is the same as an increasing headwind. Effectively, from the threshold, the aircraft had to "lose" about another 15K of IAS... whilst at a groundspeed of ~160K. For the few posters here who have flown real aircraft, and particularly Airbuses (I have flown A340s and A32x series) will know that Airbuses are "slippery", quite happy to add a few knots here and there (GS Mini, not a precise ATHR), and have a damn good wing, which all => float. Until you get the thing on the ground, the deceleration is poor, especially in ground effect.
Of course, having got the thing on the ground, with a contaminated runway, deceleration will still be poor... and from the posts / TSB (?) / Airbus, it seems that once landed everything went as expected.
Like all accidents, I suspect there will be a number of factors that all added up. No doubt the performance manual said it was OK to land on this Runway, Wet, at this weight. But to what tailwind? A wild guess that the A340 (like A320) is limited to 10K tailwind in the calcs. Very difficult for a crew, flying in poor conditions, to notice the gust veering in the latter approach stages to exceed the 10K (?) figure. Probably still OK, until the tailwind now unfairly disappears (!) in the flare / float, and this will not be factored into the Perf Manual calcs. And again, the immediate Perf Manual will probably have allowed for Wet, but not "Flooded" runway...
Go-Around in flare / after touchdown. Not really trained for... I have done one for real (ABZ), but it is purely a personal instinctive decision by one or other of the Flt Crew. Whilst with 20:20 hindsight, and maybe the Inquiry will confirm, the GA option seems a good one; I reckon a Sim exercise with this scenario (unbriefed) would see the majority doing what happened here...
Lessons: well, some obvious immediate ones for those who do fly, and take advantage of this unfortunate crew. The real / precise lessons will come out in due course from the TSB.
(posted 8 Aug)
Monday TSB Briefing
Again caveat phone quality.
Height above Threshold 50-100'
Threshold a/s 146 kt; gs 164kt
a/s at touchdown 148kt.
Again caveat phone quality.
Height above Threshold 50-100'
Threshold a/s 146 kt; gs 164kt
a/s at touchdown 148kt.
FROM : AIRBUS CUSTOMER SERVICES TOULOUSE TX530526F
The short final and landing were performed manually with the autopilot (AP) and autothrust (ATHR) disconnected at about 300 feet AGL. The aircraft was in configuration FULL with auto-brake selected to MED.
There was a right variable crosswind of about 20 kts and a tail wind component during the final stage of the approach.
At the time of touchdown, the airspeed was 143 kts and the ground speed 148 kts. Visibility was reported to be 0.5 to 0.25NM in heavy rain.
The touchdown zone is located approximately 4000 feet from the threshold of the 9000-foot runway.
The short final and landing were performed manually with the autopilot (AP) and autothrust (ATHR) disconnected at about 300 feet AGL. The aircraft was in configuration FULL with auto-brake selected to MED.
There was a right variable crosswind of about 20 kts and a tail wind component during the final stage of the approach.
At the time of touchdown, the airspeed was 143 kts and the ground speed 148 kts. Visibility was reported to be 0.5 to 0.25NM in heavy rain.
The touchdown zone is located approximately 4000 feet from the threshold of the 9000-foot runway.
1. Over threshold, IAS roughly correct, but an 18Kt tailwind.
2. Touchdown - IAS of same (correct I assume) magnitude, but now only a 5K tailwind.
3. Poor vis due heavy rain => (significantly) contaminated runway.
Nobody seems to mention the effect of the decreasing tailwind... It is the same as an increasing headwind. Effectively, from the threshold, the aircraft had to "lose" about another 15K of IAS... whilst at a groundspeed of ~160K. For the few posters here who have flown real aircraft, and particularly Airbuses (I have flown A340s and A32x series) will know that Airbuses are "slippery", quite happy to add a few knots here and there (GS Mini, not a precise ATHR), and have a damn good wing, which all => float. Until you get the thing on the ground, the deceleration is poor, especially in ground effect.
Of course, having got the thing on the ground, with a contaminated runway, deceleration will still be poor... and from the posts / TSB (?) / Airbus, it seems that once landed everything went as expected.
Like all accidents, I suspect there will be a number of factors that all added up. No doubt the performance manual said it was OK to land on this Runway, Wet, at this weight. But to what tailwind? A wild guess that the A340 (like A320) is limited to 10K tailwind in the calcs. Very difficult for a crew, flying in poor conditions, to notice the gust veering in the latter approach stages to exceed the 10K (?) figure. Probably still OK, until the tailwind now unfairly disappears (!) in the flare / float, and this will not be factored into the Perf Manual calcs. And again, the immediate Perf Manual will probably have allowed for Wet, but not "Flooded" runway...
Go-Around in flare / after touchdown. Not really trained for... I have done one for real (ABZ), but it is purely a personal instinctive decision by one or other of the Flt Crew. Whilst with 20:20 hindsight, and maybe the Inquiry will confirm, the GA option seems a good one; I reckon a Sim exercise with this scenario (unbriefed) would see the majority doing what happened here...
Lessons: well, some obvious immediate ones for those who do fly, and take advantage of this unfortunate crew. The real / precise lessons will come out in due course from the TSB.
Per Ardua ad Astraeus
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NOD - for an Airbus non-believer
, can you explain how it would handle that? Eg. a 737 in a/throttle would probably detect the increasing IAS and reduce power, if not already flaring.
(Not understanding the AB GSMini function), would the AB detect reducing GS and APPLY power, or re-apply power having taken it off for the -18kts?
, can you explain how it would handle that? Eg. a 737 in a/throttle would probably detect the increasing IAS and reduce power, if not already flaring.(Not understanding the AB GSMini function), would the AB detect reducing GS and APPLY power, or re-apply power having taken it off for the -18kts?
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Hi Mr BOAC - how goes it 
GS Mini in this instance should not be a factor - it tends to "add" target IAS when the actual Headwind is greater than wot you typed in the machine. So unless they "entered" a huge tailwind, GS Mini will not take off IAS to get GS to target. My comment was in general that the Airbus is sometimes, let us say a bit too clever, and combined with a poor / lazy ATHR, you often end up with a few knots more than ideal... usually not a problem.
As the tailwind presumably increased approaching the threshold, the ATHR would just add power to maintain target IAS. If it was "lazy" (as it sometimes is) it might have left the power on longer than necessary. As the tailwind reduced it should have taken the power off again... As you flare, and earlier if you see it is "hot", you manually close the TLs, and command idle. However, I would suggest here, these seem like minor factors...
The point I am trying to make is that Airbuses are slippery and easier to float than a Boeing, and can be hard to "get on the ground". Even at idle, with 160K GS and 15K IAS+ to lose (they almost certainly added IAS as well in the conditions), the attitude will be flatter than normal, drag less, and if you could see through the rain (!), the runway will be being eaten up quickly
The details we are guessing at will be well known to the BOI, and best left to them... I am just trying to make big picture stuff from what we know, and point out the factor of increasing headwind which seems factual from what we know, and maybe made a "tight" situation impossible
NOD - for an Airbus non-believer, can you explain how it would handle that? Eg. a 737 in a/throttle would probably detect the increasing IAS and reduce power, if not already flaring.
(Not understanding the AB GSMini function), would the AB detect reducing GS and APPLY power, or re-apply power having taken it off for the -18kts?
(Not understanding the AB GSMini function), would the AB detect reducing GS and APPLY power, or re-apply power having taken it off for the -18kts?
As the tailwind presumably increased approaching the threshold, the ATHR would just add power to maintain target IAS. If it was "lazy" (as it sometimes is) it might have left the power on longer than necessary. As the tailwind reduced it should have taken the power off again... As you flare, and earlier if you see it is "hot", you manually close the TLs, and command idle. However, I would suggest here, these seem like minor factors...
The point I am trying to make is that Airbuses are slippery and easier to float than a Boeing, and can be hard to "get on the ground". Even at idle, with 160K GS and 15K IAS+ to lose (they almost certainly added IAS as well in the conditions), the attitude will be flatter than normal, drag less, and if you could see through the rain (!), the runway will be being eaten up quickly
The details we are guessing at will be well known to the BOI, and best left to them... I am just trying to make big picture stuff from what we know, and point out the factor of increasing headwind which seems factual from what we know, and maybe made a "tight" situation impossible
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Hey NOD
Being Bus driver myself, even its A320, I think your analysis is spot on.
X wind turning into X-tail gust at short final (incresed trust to maintain IAS), and then back to almost calm wind at touchdown produces relative increasing headwind (here +15). Crew were on manual thrust from 300'agl and maybe realised the sudden +15 IAS over threshold and need for idle thrust a little late.
Same concerns on A/THR and GS-mini interaction as you touch. Also the reliability of towerwind is a factor. Speed awareness on Airbus easily gets low, which influences flare directly. Problem both ways, but certainly you often feel that threshold speed was 5-10 knots high for the flare.
Never trained go around due long land ! And agree that unprepared most would, given the situation over threshold, end doing the same as happened here.
Being Bus driver myself, even its A320, I think your analysis is spot on.
X wind turning into X-tail gust at short final (incresed trust to maintain IAS), and then back to almost calm wind at touchdown produces relative increasing headwind (here +15). Crew were on manual thrust from 300'agl and maybe realised the sudden +15 IAS over threshold and need for idle thrust a little late.
Same concerns on A/THR and GS-mini interaction as you touch. Also the reliability of towerwind is a factor. Speed awareness on Airbus easily gets low, which influences flare directly. Problem both ways, but certainly you often feel that threshold speed was 5-10 knots high for the flare.
Never trained go around due long land ! And agree that unprepared most would, given the situation over threshold, end doing the same as happened here.
ex-Tanker
Join Date: Apr 2000
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Hi Facelac,
I don't agree that most people would try to land out of a long land situation rather than go around.
The following happened to me once in CDG - Copilot flying - wind light cross - dark clouds to the south.
About 100 ft after a pretty good ILS approach, we go high - Copilot (very new) makes a brusque correction nose down and gets my full attention.
At 50 feet we are on slope but ROD high - I am about to take over when Copilot makes a hard pull on the yoke. ATS is on and not quite in retard mode, so adds thrust.
An extremely soft touchdown occurs - spoilers do not come - we get airborne again.
Copilot freezes on the controls - X wind drifts us towards the lights. I grab it and start a standard GA procedure. During the rotate we again touch the RW and this time the spoilers do come, but are retracted by the advancing thrust levers.
We clear the ground as advertised and live to make another approach, which I fly. This time there is an extremely gusty crosswind - the first gust of which must have hit us at 100ft on the first approach.
Point of this is to show that a GA will almost always save you - although like you, we never practised it so late in the sequence.
FC.
I don't agree that most people would try to land out of a long land situation rather than go around.
The following happened to me once in CDG - Copilot flying - wind light cross - dark clouds to the south.
About 100 ft after a pretty good ILS approach, we go high - Copilot (very new) makes a brusque correction nose down and gets my full attention.
At 50 feet we are on slope but ROD high - I am about to take over when Copilot makes a hard pull on the yoke. ATS is on and not quite in retard mode, so adds thrust.
An extremely soft touchdown occurs - spoilers do not come - we get airborne again.
Copilot freezes on the controls - X wind drifts us towards the lights. I grab it and start a standard GA procedure. During the rotate we again touch the RW and this time the spoilers do come, but are retracted by the advancing thrust levers.
We clear the ground as advertised and live to make another approach, which I fly. This time there is an extremely gusty crosswind - the first gust of which must have hit us at 100ft on the first approach.
Point of this is to show that a GA will almost always save you - although like you, we never practised it so late in the sequence.
FC.