An amazing video of the landing of a Lufthansa jet in Germany in ridiculous crosswinds has got us thinking today:
The pilots tried a standard technique called "a crab," in which the nose is pointed into the wind, then the rudder is used at the last minute to kick the plane's nose straight down the runway. Only in this case, the wind lifted the upwind wing and that was that.
The pilots did a terrific job aborting the landing and avoiding what would've been a disaster.
But, perhaps, lost in the adulation is the fact the pilots tried to land in the first place. According to the Daily Mail, winds were blowing at 155 mph at the time. As told, something's not right with this story (Update: See Aaron's comments below) because the "crosswind component" (the amount of crosswind in which an A320 has been demonstrated to land safely) is in the 40 knot range.
If everything is as reported, it could've been one of those kinds of pilot errors that often leaves people dead.
The story makes sense. The crosswind component refers to the relative amount of crosswind. If the wind was coming directly from the left or the right of the track of the plane, then the crosswind component would be 155mph. More likely, it was landing mostly into the wind. If the wind was at a 45º angle to the plane, the crosswind component would be about 77mph. If the wind was only 10º or 20º crosswind or so, meaning the plane was mostly flying into the wind -- just at a slight angle to it -- it would have been within the demonstrated maximum crosswind component.
I can tell you've landed an airliner, Aaron.
From what I can find, the crosswind component 60 degrees off the nose is 40 knots, but I don't have the specific numbers. The crab angle here looks to be a bout 30 degrees. Just before he lost it, he started to take the crab angle out, and then -- to get back on the centerline -- he increased it to about 45 degrees.
It was at that point, of course, where he should've firewalled the throttle and gotten out of there. And, indeed, he/she might very well have done that; it's difficult to tell, but I'm sure it takes the engines time to spool up. It was not a stabilized approach. And the other aspect of the performance numbers of the plane is they're numbers put together by test pilots. To me, this looks pretty close to have risked so many lives. Why not just land at an alternate airport?
Unrelated, but still a fascinating glimpse into how hard these folks are working (and also because it's one of my favorite blogs) is this one.
I've not landed an airliner, but I've landed smaller planes numerous times in direct crosswind.
I looked up the historical weather data for Munich around that time and the 155mph number is what's incorrect in the story. Winds were 33kts to 49kts at the time, or gusting to about 55mph. So somebody added a "1" in front of that number over at the Daily Mail or wherever they got their story from.
Winds were coming out of 290º. They were landing on runway 23, which is about heading 230º. Wind, theoretically, was hitting the plane at a 50º angle. The runway was chosen because it was the only runway that the airport gave them. After the go-around they landed on runway 33, at about heading 330º, where the wind would theoretically be hitting the plane at a 40º angle instead from the other side.
In either landing, it was within safe limits (30 kts or 38 kts crosswind). What it looks like is that the plane hit some nasty wind shear out of the blue. It happens. From what I've seen and read, I don't think the pilot did anything wrong other than demanding from tower that they get the other runway the first time.
Looking at the video a few more times, it looks like the real problem was after the wheels touched, everything was stable up to that point and then it veers quickly off to the left. It appears that the pilot was initiating to go around at that point.
As for the idea of landing at an alternate airport, I don't think it was necessary. The pilots are trained and the aircraft are created to work in these conditions and what was encountered seems to be an unusual anomaly.
Ah, OK, I *thought* that 155 sounded suspicious. That does change the story.
BTW, I made a landing (several actually) pretty much like this last weekend.
There wasn't a lick of wind at the time. :*(
At 155 mph, he could have just pointed the nose into it and hovered it down.
I've had that inconveniently timed gust myself, or so I like to think, what with the alternative explanation for some of my lesser quality landings being far more damaging to my confidence and self-esteem.
It would be pretty hard to get one of my wingtips all the way to the ground like that, but that's mostly a factor of how short RV wings are.
Philip Greenspun, the Harvard dude, laments on his blog today that "Out of the hundreds of newspaper accounts of this incident, none mentioned the fact that nothing required the pilots to attempt to land at Hamburg in this huge windstorm in the first place."
Had you beat by a day, Phil. :*)
The limitations I have seen for this airplane lists the crosswind componant for the A320 at 29 kts on a dry runway.
The A320 family of aircraft are good, safe airplanes but they can be unpredictable in gusty crosswinds as there is little or no "feel" in this fly-by-wire aircraft and the pilot can frequently run out of side-stick authority without the airplane responding fast enough. In the video it appears a gust lifted the right wing and then the only option was to abort the landing as the Lufthansa pilots did.
The approach did in fact appear stabalized up until the flair and the abort was initiated at the worst possible time (practically speaking not judgementally), the power levers were already retarded to idle to prepare for the touchdown. This would have made the spool up time longer and the go-around trickier.
The safest technique in these conditions is to land "firmly" so wheel spin-up deploys the ground spoilers thus destroying the lift and settling the aircrafts wieght on its gear so it stays on the pavement. In the video it appears the pilots never got the chance the plant the gear, so they did the right thing and went around. Hey, it happens.
Boy, well down the runway, he was getting pushed over to the left and then he tried to "save it" by increasing the crab angle, which did, of course, get him back near the cneterline and THEN the gust lifted the wing.
You know what? I don't think it was a wind gust that lifted that wing. Watching the video again (and again and again and again) it also looks like the left wheel had touched down just before that gust came up. The sideload on those wheels on that side... I think..... is what led to the wing coming up.
BTW, I wonder how it is a person happened to be there with a video camera. I tried that once over at MSP; it took about 45 seconds for the cops to come.