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LH A320 Rough Landing @ Hamburg

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LH A320 Rough Landing @ Hamburg

Old 3rd Mar 2008, 17:29
  #121 (permalink)  
 
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Question from a non-pilot:

If the crab had been taken out slightly later and the starboard wing dipped into the wind would this have been avoided?
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Old 3rd Mar 2008, 17:29
  #122 (permalink)  
 
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Perhaps we should remember that most of the "great unwashed" think that everything on an airliner is "automatic" and that we just sit there and press a few buttons everyday. Maybe these pictures will cause those people to think that it's not as easy as they think! Landing in marginal conditions can be demanding for even an experienced pilot on type but it is all about knowing the a/c limitations (and your own) and being prepared to make a decision to abandon an approach and/or landing which is not going as planned.

In short, if in doubt then don't!
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Old 3rd Mar 2008, 17:32
  #123 (permalink)  
 
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Airbus croswind and turbulence technique is easier to describe in front of someone, not as easy in writing but I will have a go.

I have 7,500 hours on 320/1/330 and had factory training thoughout.


FBW will do a fantastic job, up to a limit - it will correct disturbances from the flightpath well but only so far.

If you have an extra disturbance through turbulence that further affects the aeroplane, FBW wants a correction to bring it back within its capabilities and no more. Hence, in gusty crosswinds, you WILL hit the stops, but only for a short time - quick, rapid inputs and then release to allow FBW to continue doing it's job.

This works, it was taught in training and will result in as stable an approcah as can be expected in some of foul weather that we all encounter from time to time.

It is radically different from Boeing because of the flight laws and way the Airbus operates. You cannot therefore compare the two, although I would be interested to hear from any 777 drivers who's aeroplane use a similar adaptation of the Airbus FBW system - from memory. There are significant differences due to the backdrive required but will stand to be corrected.

Beyond that, lay off the drift on approach, kick it off in the flare, dip a wing and land into wind wheel first - it works a treat
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Old 3rd Mar 2008, 17:33
  #124 (permalink)  
 
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I agree, shame he didnt put a bit of in to wind aileron prior to touch down...
I think the Air France video is the perfect demonstration to a text book cross wind landing.
The airbus can do them! Its all a bit vague, but it can do them. (Hope no spotters are about with video recorders on my windy landings!!!!)
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Old 3rd Mar 2008, 17:37
  #125 (permalink)  
PJ2
 
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Nod;
On Approach, from 50R, it enters "Flare Mode". This is essentially "Normal Law" but with a Pitch added factor (tries to push nose down). In Roll, AFAIK it is still Normal Law. It does not go back to "Direct Law (Ground Mode)" until 5s after landing...
Fully agree. That's the way the Airbus works.

(edited for a response to javelin)

javelin:
Beyond that, lay off the drift on approach, kick it off in the flare, dip a wing and land into wind wheel first - it works a treat
Yes, but only up to the point where physics permits. Only so much crab or bank angle can be achieved to counter the crosswind forces. Once that crab or wing-low limit is reached and the forces remain in favour of the crosswind, the airplane will be blown downwind and off the runway perhaps even against the friction of the landing gear, (a whole new set of problems such as runway contamination, side-loads etc), just as this one was during the go-around. At this point, it has nothing to do with skill, experience and the capabilities of the airplane - the physical forces are beyond the airplane's capacity to counter.

As an aside, I would ask the Boeing enthusiasts-Airbus bashers, do you want to force the airplane onto the ground in circumstances far outside the manual or are the limits to be respected? There is a post down below which speaks of commercial pressures as well...do they enter into this? Does Pride? Perhaps the real fact that was "demonstrated" in the crosswind landing tests Airbus did for the 320 was, the airplane cannot counter the physical forces described above. Javelin, what did Airbus say about those limits?

Cheers,
PJ2

Last edited by PJ2; 3rd Mar 2008 at 19:21.
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Old 3rd Mar 2008, 17:39
  #126 (permalink)  
 
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In tough, gusty xwind conditions, PLANT IT ON.
Align your aircraft to the runway with appropriate rudder/ailerons and MINIMUM flare.
With GUSTY crosswinds, any attempt at finesse and smooth landing is giving
"the gusts" TOO much of an opportunity to ruin your day.
Don't "hang it out there on the table", because there's a chance of getting it "chopped off".
It does NOT matter if the pax think you did a poor job at it. YOU know better!
I assume the AB will let you 'plant it on', won't it?

Just statements of opinion.
Making ZERO suggestions/judgments of what actually occurred during the Lufthansa incident.
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Old 3rd Mar 2008, 17:59
  #127 (permalink)  
 
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BBC. Badly Biased Claptrap.

BBC, for one, have yet another cock-up, put together by their resident 'aviation expert', no doubt, showing a picture of an AA 767 on the ground, surrounded by emergency vehicles. Then follows the LH 320 X wind wing touch video clip with a voice over explaining that they are one and the same aircraft.
Brilliant journalism, once again.
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Old 3rd Mar 2008, 18:01
  #128 (permalink)  
 
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An Associated Press report on Yahoo is now reporting that the plane was hit by a 155 MPH wind as it tried to land. I have a hard time believing that either 155MPH or even 155KPH were recorded. Good think tornados are rare over there, otherwise that would be in the story too.

http://news.yahoo.com/s/ap/20080303/...ough_landing_1
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Old 3rd Mar 2008, 18:06
  #129 (permalink)  
 
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rubik 101: Don't be so hard on the journos this time!
Also just watched the BBC Six O'clock news. I think the American airlines clip in the snow was the 'Gallery' playing the wrong clip: the diversion to Glasgow story was not covered but they had pictures.
The Hamburg clip came on shortly thereafter.
They did say: "The pilot needs a pay rise". Some on here might have adifferent view!
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Old 3rd Mar 2008, 18:09
  #130 (permalink)  
 
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Paktrickal;

I was just about to post the same link. When I saw the "155 mph winds" I thought "oh yes"
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Old 3rd Mar 2008, 18:10
  #131 (permalink)  
 
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In an earlier (now deleted post?) One off pilot asked “Should the landing have been attempted?” This is exactly the right question to ask.
In this thread too many people are answering the wrong question; instead of discussing flight techniques they should be considering “should we be landing in these conditions”, and how can we assess such situations to choose the safest option. Decisions such as these should be routine, but they continually appear as problem areas in approach and landing accidents.

The assessment of weather conditions for landing usually involves some degree of unknown, thus individual judgment is required – experience – knowledge, and skilful disciplined thought.

Unfortunately, the demands of today’s industry do not easy this task; there are many commercial and operational pressures which promote the ‘Press on’ option. Many of the marginal or risky options have become the industry norm, which crews are ‘expected’ to carry out, influenced by peer pressure or covert management policy.

Crews should remember that wind measurement and reporting is not an exact science. The paper on ‘Safety aspects of aircraft operations in crosswind’ discusses crosswind landings and the associated hazards. Wind speed measurements are subject to considerable error, gusts more so than steady state winds.

Very few aircraft have an AFM defined crosswind limit; a max demonstrated value is more normal and unless specifically stated it may not include gusts. Many operators might overlook the subtleties of certification when defining their operating limits, e.g. the conditions in which the demonstrated values were achieved. Manufactures are required to show that the aircraft is safe in both left and right crosswinds, thus the test conditions tend to be flown in winds at 90 deg to the runway enabling approaches from each end. Also for accurate measurements, the gust values may be lower than normal; thus, there may not have been any evaluation of gusts or the effects of veer.
The test teams will have had opportunity to workup in the conditions, incrementally assessing the aircraft's reaction and use of alternative handling techniques. The resultant ‘demonstrated value’ (and recommended technique) should be representative of an average pilot ‘without use of undue skill or effort’ (certification term). But I have yet to find any pilots who rate themselves as ‘below average’, neither any who will first fly an evaluation approach; thus for may pilots encountering limiting winds it is a new experience – a first time ‘test’ of their skill and judgment without practice (simulators IMHO, are not sufficient in these circumstances).

The safest option would be the earlier use of knowledge, experience, and judgment to evaluate the conditions and consider any other effects, i.e. wet runway; never dismiss the option to divert without careful reasoning.
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Old 3rd Mar 2008, 18:12
  #132 (permalink)  
 
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I agree that ALL pilots deserve a pay rise for flying last week! I had two of the roughest approaches in my 35 years of flying landing in UK last week.
Let's award ourselves at least a pat on the back!
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Old 3rd Mar 2008, 18:27
  #133 (permalink)  
 
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Regardless of the question of whether GA should have been called earlier, it'd be great if I could get some clarification on another point that seems to be unconfirmed in this thread.

As I understood it, the Airbus FBW system when in Normal Mode will do its best to keep the wings as level as possible when the sidestick is centred. Does this extend to automatically correcting the roll effect of a reasonably hard rudder deflection or not?

Thanks in advance!
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Old 3rd Mar 2008, 18:30
  #134 (permalink)  
 
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Pkpf68-77

During spells when the wind gets stronger for a few seconds - often near or in showers - the wind direction tends to veer.
Your 290 wind can easily become 310-320 making the crosswind component jump to a value well above limits.

I do not know if this is written down anywhere in Aviation Met literature but having spent hundreds of hours on long shifts staring at anemo (dials) I can confirm this is indeed the case.
This is called "Learn to Love Left Crosswind."

With the wind from the left you get the gusts more on the nose -> good .

Whereas with the crosswind from the right, as in this case, the gusts veer to worsen the situation -> bad .
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Old 3rd Mar 2008, 18:51
  #135 (permalink)  
 
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Completely concur with KC135777 and the concept of "planting" it firmly and swiftly back on terra firma. All the new generation a/c seem to be getting wider wingspans and correspondingly lower angles of bank tolerable at landing.
Interestingly the commonly posted U tube of the Boeing 777 demonstrating max Xwind landing, seems to land on the runway offset and then "kick" it straight before lowering the nosewheel.
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Old 3rd Mar 2008, 18:59
  #136 (permalink)  
 
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Talking

I bet a helicopter pilot wouldn't consider landing in conditions like that, he'd divert immediately due to good airmanship and judgement hehe
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Old 3rd Mar 2008, 19:00
  #137 (permalink)  
 
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Originally Posted by CAT III DUAL View Post
38kts is not a limitation, its only a demonstrated crosswind back from the
old days of flight testing that beast for certification.

If you are Chuck Yeager and think you can handle it with 60, no problem.
There is NO official limitation for crosswind (except for Autoland approaches)
That would depend upon the company SOP. The majority of airline SOPs that I've used list crosswind LIMITS, not maximum demonstrated crosswinds. If the company puts it in the SOP as a limitation then that is EXACTLY what it is, no matter how it was derived in the first place.

I would be pleased to hear just how YOU personally determine how far above the maximum demonstrated crosswind is safe - because if no one has demonstrated greater you are in uncharted territory.

Last edited by moggiee; 4th Mar 2008 at 00:00.
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Old 3rd Mar 2008, 19:01
  #138 (permalink)  
 
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LH vs AZ (Germany Vs Italy)

For once the Italians can be proud of being more efficient than the Germans...this AZ MD11 did definitely better than the LH A320.

http://www.youtube.com/watch?v=M1w4K...eature=related


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Old 3rd Mar 2008, 19:07
  #139 (permalink)  
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Javelin

Beyond that, lay off the drift on approach, kick it off in the flare, dip a wing and land into wind wheel first - it works a treat
That is exactly how I was taught, apart from the 'kick it off' bit - more of a squeeze really.

However the one trime it frightened me (as I and others have alluded to) is when the into wind wing kept on coming up despite full sidestick. So in my case there was no 'dipping a wing' because 'it' would not let me. As I stated before an A320 'old hand' told me to take the drift off earlier to give the FBW a chance to sort itself out.

Perhaps I had experienced a temporary gust outside the limits - I will never know.

You asked about the 777. I only flew it for a year as an F/O and it was an absolute delight to fly and felt like a real aircraft - different FBW logic entirely to the 320. I always had confidence that the 777 would perform as advertised - not so in the 320.

Back on the 737 following a 2 year break on the 757 and both types behave very well in a xwind - the 737 marginally better than the 757. I've only twice landed the 737 in a limiting xwind and on both occasions I was nowhere near the roll authority limit.

Incidentally the 320 was a great aircraft in many respects, especially when you consider how old the FBW design logic is. What I did find worrying is the reluctance for Airbus Industrie to consider that they may have a problem with any of their design - it took a crumpled aircraft in Bilbao before they accepted what other operators had been telling them for some time - the ELAC design as it stood then was dangerous.


Regards
Exeng
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Old 3rd Mar 2008, 19:39
  #140 (permalink)  
 
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Paradise Lost:
Interestingly the commonly posted U tube of the Boeing 777 demonstrating max Xwind landing, seems to land on the runway offset and then "kick" it straight before lowering the nosewheel.
Doesn't the B777 have main gear with features similar to the B52? That's what allows the big bomber to land with a crosswind and then straighten out. I'm sure I saw a reference to the 777 using similar technology but I can't find it now so perhaps I dreamt it. I know they've got some fancy main gear tricks to help with take-off on a shorter runway.
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