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Hamburg Wing-strike – Pilot a Hero or Lacking Technique?

By admin | March 3, 2008

By now, I’m sure if you’re at all connected to aviation (or the nightly news for that matter) you’ve seen the video of the Lufthansa A320 landing in a crosswind in Hamburg, Germany. The media, once again, seems to be less knowledgeable about aviation than they are about selling advertising because you read headlines such as:

“German Airline Says Pilot Averted Major Crash” – Rueters

“Lufthansa ‘Hero’ Pilot Saves Life of 137 Passengers” – maltaStar.com

“Pilot Saves Jet From Disaster in Gale” – Independent UK

Here’s the problem. This near “Disaster” was not the cause of anything other than the pilot’s inability to control the aircraft. How do I know? I’ve been landing airliners in stronger crosswinds than this for years and yes, even in tropical storms. (Never hurricanes. That’s suicidal in it’s own right.)

How it’s supposed to happen: Crosswind Landing Technique

Handling crosswinds in an aircraft is all about understanding vectors. You have to fight the horizontal vector of the crosswind with either a competing vector of your own by flying into the wind enough to remain aligned with the runway, or with a horizontal component of lift created by banking the aircraft into the wind. The first method is easy. If the wind is coming from the right, you turn your nose into it using the wind to keep your aircraft aligned with the runway. This is called a side-slip or a “crab,” and is the most common method for dealing with crosswinds in all phases of flight, except for the touchdown.

And that’s precisely where the second method must be used. This one’s a little more complicated. Since a landing while in a “crab” will put extreme side loads on the landing gear, possibly collapsing them, a pilot must straighten the nose of the aircraft prior to touchdown. This is done with the rudder pedals that control the yaw, or side to side movement of the nose of the aircraft. Left rudder in a right crab will bring the wheels in line with the runway, but there is a catch. You’ve taken away your competing horizontal vector against the wind, and there’s nothing to keep it from blowing you off the runway. So off the runway you shall go…unless you find another way of creating that competing horizontal vector.

This is accomplished by lowering the upwind wing (the right wing, in this instance). Since aircraft lift only ever points straight up (in relation to the aircraft, not the ground), when you bank the wings you are producing a horizontal component of lift, exactly the horizontal vector we need to counter the wind. So, by simultaneously straightening the nose and dipping the right wing, the horizontal component of lift will counter the affects of the crosswind and bring you safely to earth.

Watch this video of a Northwest A319 which demonstrates textbook-perfect technique. Much like the Lufthansa Airbus, this A319 flies a “crab” angle until just prior to touchdown when the pilot inserts left rudder, straightening the nose with the runway. But watch how the Northwest pilot dips the right wing into the wind, thereby preventing any gusts from picking it up, and making a very smooth landing on the right main landing gear, just as it should be.

How it Happened in Hamburg:

So what happened in Hamburg? Exactly as I described above, you see the aircraft flying sideways in a “crab” to counter the wind. The approach looks textbook as the pilot kicks the left rudder to align the nose with the runway, but one thing never happens. The pilot doesn’t lower the right wing. In fact, he seems to raise it. The effect is entirely predictable, and the aircraft veers sharply left, nearly resulting in an infinitely more exciting video for those two amateur videographers.

“But it was a gust of wind the pilots could have never planned for.”

Rubbish. There are gusts of winds all the time, many stronger than the one that pushed this A320 around like a toy. The pilot is (or should be) trained to handle these gusts closed to the runway without damaging the left wing. In fact, most crosswind wing-strikes happen on the upwind wing (the right wing in this case) because the pilot has compensated for the crosswind with more bank than the ground will allow. So why did this happen on the downwind wing? Because the pilot did not dip the right wing as is fundamental in landing an aircraft in crosswinds. How do we know? Had the pilot dipped the right wing like he was supposed to, and gust of wind would have pushed the wing down, not up. The aircraft would still have drifted to the left with the gust, however this would have been easily corrected by adding more horizontal component of lift with more right bank.

Why did the pilot raise the right wing instead of lower it? I’m going to give the pilot the benefit of the doubt that he did not do the exact wrong thing by raising the right wing. More probably, the wing raised itself because the pilot failed to make the necessary right bank correction. Watch the wings as the left rudder is kicked to align the aircraft with the runway. The left turn of the nose causes the left wing to move slower through the air, and the right wing to move faster. This means the right wing will be producing significantly more lift than the left, and it will want to raise. Once the wing raises, the wind catches it, and the almost-mayhem ensues. It takes the pilot several seconds to lower the wing to prevent the aircraft from drifting off of the runway, but the damage was already done.

Notice the difference in outcome of the first example where the Northwest pilot lowers the right wing into wind and has a nice comfortable landing compared to the Hamburg version. The crab angles are nearly identical which indicates comparable wind (to me the NWA crab looks a little more aggressive which would mean they had a stronger crosswind, but I’ll leave that judgment to the reader.)

What seems obvious to us pilots as a botched landing due to poor technique is apparently not so obvious to the general public. The moral of the story is not that pilots lack the technique like the one that made international news with the Hamburg almost-landing, rather that pilots are so skilled that they make landings in stronger crosswinds than this multiple times a day, without videos making it further than flightlevel350.com. And that this wouldn’t have happened if it was a Boeing… ;)

Edit – For those of you who takes things too seriously to notice the little wink emoticon, or to appreciate the Airbus vs. Boeing banter that inevitibly takes place in the online aviation community, you obviously missed the humor in the last sentence.  Don’t take things so seriously.  Of course it could happen in a Boeing.

But this never would have happened if it was a Douglas… ;)   (<— notice the wink emoticon.  Typically used to demote sarcasm or tongue-in-cheek.)

Topics: Videos | Comments

  • delphin
    you need currage to land like this.
  • delphin
    you must have currege to land in so a situation
  • Airport Dog
    Sorry, but I think this is the 'textbook' example of a crosswind landing in a high performance, swept wing aircraft.

    http://www.youtube.com/watch?v=LAljM7CaY10&feat...

    The idea is to stay in the crab until you feel like you are about to touch down. Then, and only then, to you kick in the rudder to align the aircraft with the runway. This reduces the need to lower the upwind wing (if not eliminating the need completely). Landing in a full side slip may be an option in a C172, but in a swept wing airplane like a Citation X or a Boeing 727, it won't work. In the Citation X, the wing sweep is so significant that too much bank while in a nose high (flare) position will surely cause a wing tip strike. On the 727, the problem is not so much striking the wingtip as it is the outboard flap. If I remember correctly, we were taught in both aircraft that somewhere in the neighborhood of 10 degrees of bank will put metal on pavement. Ten degrees of bank is not much to work with at all. Now in the Luftansa Hamburg and the Northwest videos it seems the pilots may have started the round out and flare a little too soon and thereby put themselves in a vulnerable position of having to add some major bank angle to correct. That said, when the wind is really choppy (not just gusty), airspeed variations of plus or minus 15 or more knots in addition to large changes in crab and pitch angle make it difficult to judge the flare. On top of that, you may judge it correctly but a gust of wind (or the cessation of a gust) will change things in short order when you are already committed to the round out. All you can do is the best you can do at each split second of variability that mother nature throws at you. Remember too, a 20 knot crosswind can be very different from one airport and weather system to another. Terrain and other obstacles play a large part in changing things up. It would be foolish to assume every landing (crosswind or not) is the same; on the contrary, they are almost all unique for one reason or another. On another note, I have to agree with Blu Yonder. As professionals, we need to learn from mistakes, including our own. Granted, the media may not accurately report on aviation, among other topics, but talking down about an incident like this is immature. By the way, a crab is not a side slip as you state early in your comment. You go from a crab into a side slip to align the aircraft with the runway for landing (unless you're flying a B-52). Stay safe everyone and good flying.
  • Blu Yonder
    I read your blog and I really find it hard to believe you are actually an airline pilot. Words like ".. rubbish.." regarding something like a crosswind landing sound very immature and unprofessional. Firstly we should NEVER judge without a proper DFDR report. Secondly you should NEVER consider yourself a know-it-all and the macho attitude" this can never happen to me" is very unbecoming to an airline pilot. I was always trained to learn from errors happening around us to prevent it happening again. So i fail to understand your smart Alec blog explaining vectors and crab angles during a crosswind landing.
    Finally your comment "...and this would have never happened in a Boeing..." is the last nail in the coffin. Never further from the truth!
    On a lighter note, while landing in Hamburg some months ago in similar conditions, my first officer spotted camera crew shooting approaches just before the runway! Someone looking for a scoop maybe!!

    regards
  • Paul
    Pardon me if I seem ignorant, but I still disagree about this. (For what it's worth, I'm a beginner pilot, and have been around planes my whole life)

    For one, I find the comparison between the NW and LH quite poor.

    1) It seems as though, after the NW straightens out, he hangs out for quite a while with level wings, just dipping the wing a second before touchdown. This almost makes me wonder if the wing dip itself was in fact an error (just a wing-low landing) or even a corrective action, rather than a preventive action

    2) The NW also was much higher above the runway when it straightened out, and even when it dipped it's wing, as opposed to the LH straightening out. I am also aware that some of this thought may be distorted by poor depth perception given the end-of-runway shot and a noticeable dip in the runway, but I still think that's a fair statement.

    3) The winds are clearly...crappy, to say the least, in the LH video. In the NW vid, they seem to at least be steady, and weather isn't too degraded, as shown by the sky. Now, that being said, I understand the wing-low is the preventive action for crosswind, but you can only go so far down with one wing low. This video looks to me almost as if it picked the plane off the runway as it was about to touchdown, rather than pushing it out of the air.


    In any case, this is an amazing video to watch, I find.
  • Boeing7xx
    Naked eye analysis (youtube'ing the whole thing) can never replace the DFDR, so unless you really had your hands on the DFDR its quite unlikely that you'd be able to figure out what were the winds gusts and what was the reason for the angle correction, and why the dead rudder applied did not bring out the results you'd expect.

    PS: The last line is really messed up. No pilot worth his salt makes such comments.
  • J. Nabrand
    Well explained, just wrecked by the last sentence. I sence some frustration there.
    I reckon Airbus and Boeing are just as safe, reliable and well built. So I do not see any added value to the story mentioning "And that this wouldn’t have happened if it was a Boeing… " It may just as well have been a Boeing in the hands of the same pilot.
    He still managed to keep it together though and correct his "mistake
  • Dave
    No mention of dutch roll? Heavy metal...the swept wing kind...will roll sharply with abrupt rudder inputs. Big iron usually have rudder movement limiters during high speed flight, but full authority at landing speeds. Smooth coordinated control inputs are the key.
  • LLL
    Can't see any flaps, was this guy really trying to land?
  • Mike
    I'm a pilot as well and it is clear what happened. Journalists are stupid, they should get proper information before publishing rubbish. Any pilot will tell you that it was a clear and elementary pilot mistake. This stuff is tought at the very beginning of any flight course. Whoever flies knows this, even just a freshly winged pilot.
  • davin
    I'm only a gamer and I know I need to dip my wing into the wing when I kick the nose with the rudder on landing...
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