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- - Flight Patterns (http://www.peachparts.com/shopforum/showthread.php?t=118545)

Quote:

Originally Posted by dmorrison

Watch a A320 the next time it lands in a cross wind. They have to pump the control stick, in aileron movement, to create the crosswind technique.

That's an interesting response to what, if you think about it, amounts to a pretty significant change in the way an aircraft is controlled.

Quote:

Originally Posted by tangofox007

And all these years I thought it was "roll." I reckon I need to study up on them there erodynamik principuls.

Ahh yes fingers typing faster than the brain can engage. Sorry about that. I wasn't an english major I was a meter--meaterr--meteorioklt--weather major.

I also have a bad habit of typing "woudl" instead of "would". Been doing that ever since the typing class in High School. You know back when we had manual typewriters and walked 5 miles to school, up hill , both ways :D

Dave

Quote:

Originally Posted by Brian Carlton

That's just amazing. I've never seen anything that severe.

I don't see how the 747-200 ever could possibly align itself with the runway centerline without taking the gear right out.

The 747-400 look as though it dropped in the runway like a brick. Unbelievable that the airplane took that abuse with no damage.

No kidding. Kai Tak International was one of the worst places on the planet for an airport.

Crazy stuff happens inside too! I 'arrived' at LAX once when there must have been a substantial crosswind. At the instant of touchdown, I honestly thought we'd crashed into something. The side loading was so severe that almost every left-facing overhead bin on that MD-11 popped open and spewed their contents out on top of the pax.

A321 x-wind landing at Lisbon

B52's don't have a problem with crosswind.

Quote:

Originally Posted by Jim Anderson

B52's don't have a problem with crosswind.

They do have the crosswind landing gear. But it does have a limit. And what thre do if the crosswind limit is exceeded I'm not sure. Low wing technique could be interesting in the B52. Can't really dip a wing to much. And that would be the only option if the crosswind was beyond the normal limit. Or land in a crab.

When I had to land with the 50kt cross wind in Lajes. You first hold on because with those winds it was continuous moderate turbulence, sometimes sever. And land in a crab with all the rudder in.

Thoughout my years of flying I have found that the worst crosswind is 3 kts, yea 3 kts. I think we relax and allow the aircraft to land in a slight crab which gars you. The times I have had to land at the limits its been a greaser. Guess were working hard and it works out.

Dave

Quote:

Originally Posted by dmorrison

We find 2 kinds of ex military pilots in the airline industry. And this is not always a hard and fast rule. Those who flew fighters and those who flew tranport aircraft or large bombers. Fighters are designed to land in a crab. Their gear is designed for the sideload and it works well for them. They also don't use an extensive flare technique. Large aircraft pilots are taught wing low landing technique. You approach in a crab. At the point that you are comfortable ( and this varies by pilot from 30-200ft above the runway) you apply the rudder to align the aircraft with the runway. To counteract the aircrafts tendancy to drift off the runway you apply, or drop the upwind wing slightly. This cross control manuever will allow the crab to be eliminated. With high winds you may touchdown on the upwind main wheel first ant then the downwind wheel will touchdown with spoiler deployment. All aircraft up to the An225 should be flown this way.
A few, and I mean very few pilots think the aircraft should be landed in a crab. I personally dont' like it. And I dont' think the aircraft likes it either.
( the C-5 and the B52 had crasswind landing gear, you rotate the gear to align them with the runway while the body is still crabbed. I understand this was removed inthe C-5B model.

I know that civilian trained pilots are taught this techique from day one. So it is natural for them.
An interesting sidenote. The newer Airbus aircraft that use computer controled flight controls are landed differently. The side stick controller when applied gives a "certain role RATE". Not a control input. Boeings give you a actual aileron movement depending on the amount of control input. When we apply the cross control techniques we input the controls and then maintain the input. But the airbus is giving you a role rate. Watch a A320 the next time it lands in a cross wind. They have to pump the control stick, in aileron movement, to create the crosswind technique.

Heres a few "non standerd landings"

http://www.airliners.net/open.file?id=229317&WxsIERv=Obrvat%20747-2W6OZ&WdsYXMg=Nve%20Puvan&QtODMg=Ubat%20Xbat%20-%20Xnv%20Gnx%20Vagreangvbany%20%28UXT%20%2F%20IUUU%29%20%28pybfrq%29&ERDLTkt=Puvan%20-%20Ubat%20Xbat&ktODMp=1993&BP=0&WNEb25u=Qnely%20Punczna&xsIERvdWdsY=O-2450&MgTUQtODMgKE=Lrg%20nabgure%20aba-fgnaqneq%20ynaqvat%20ng%20Xnv%20Gnx.%20Guvf%20jnf%20gur%20svefg%20cvpgher%20V%20rire%20tbg%20choyvfu rq.&YXMgTUQtODMgKERD=19469&NEb25uZWxs=2002-04-14%2000%3A00%3A00&ODJ9dvCE=&O89Dcjdg=&static=yes&sok=JURER%20%20%28nvepensg_trarevp%20YVXR%20%27Obrv at%20747%25%27%29%20NAQ%20%28cynpr%20%3D%20%27Ubat%20Xbat%20-%20Xnv%20Gnx%20Vagreangvbany%20%28UXT%20%2F%20IUUU%29%20%28pybfrq%29%27%29%20NAQ%20%28ZNGPU%20%28nve pensg%2Cnveyvar%2Ccynpr%2Ccubgb_qngr%2Cpbhagel%2Cerznex%2Ccubgbtencure%2Crznvy%2Clrne%2Cert%2Cnvepen sg_trarevp%2Cpa%2Cpbqr%29%20NTNVAFG%20%28%27%2B%22ynaqvat%22%27%20VA%20OBBYRNA%20ZBQR%29%29%20%20beq re%20ol%20cubgb_vq%20QRFP&photo_nr=38&prev_id=247814&next_id=223246

http://www.airliners.net/open.file?id=047556&WxsIERv=Obrvat%20747-4...&WdsYXMg=Puvan%20Nveyvarf&QtODMg=Ubat%20Xbat%20-%20Xnv%20Gnx%20Vagreangvbany%20%28UXT%20%2F%20IUUU%29%20%28pybfrq%29&ERDLTkt=Puvan%20-%20Ubat%20Xbat&ktODMp=Whar%201997&BP=0&WNEb25u=Fnzhry%20yb&xsIERvdWdsY=&MgTUQtODMgKE=Penml%20ynaqvat %20nf%20lbh%20pna%20frr%20fcbvyref%20naq%20gur%20gver%20genpx%20pyrneyl.%20Shyy%20senzr%20naq%20gnxr a%20sebz%20Ornpba%20Uvyy%20jvgu%20800%20zz%20yraf.&YXMgTUQtODMgKERD=817601&NEb25uZWxs=1999-09-19%2000%3A00%3A00&ODJ9dvCE=&O89Dcjdg=&static=yes&sok=JURER%20%20%28nvepensg_trarevp%20YVXR%20%27Obrv at%20747%25%27%29%20NAQ%20%28cynpr%20%3D%20%27Ubat%20Xbat%20-%20Xnv%20Gnx%20Vagreangvbany%20%28UXT%20%2F%20IUUU%29%20%28pybfrq%29%27%29%20NAQ%20%28ZNGPU%20%28nve pensg%2Cnveyvar%2Ccynpr%2Ccubgb_qngr%2Cpbhagel%2Cerznex%2Ccubgbtencure%2Crznvy%2Clrne%2Cert%2Cnvepen sg_trarevp%2Cpa%2Cpbqr%29%20NTNVAFG%20%28%27%2B%22ynaqvat%22%27%20VA%20OBBYRNA%20ZBQR%29%29%20%20beq re%20ol%20cubgb_vq%20QRFP&photo_nr=90&prev_id=047761&next_id=NEXTID

Dave

I wonder if they had to air out and clean all the seats after that one......

KaiTak was the worst - the approach was, in my opinion, downright dangerous. They called it the "checkerboard approach". There was a giant "checkerboard" on the hillside that pilots would use on a visual approach. I have seen several widebodies "crab" on the runway.

In another previous thread someone mentioned how a plane used sideslip until the gear made contact with the runway - don't know if this was intentional or not. Glider pilots use this technique a lot to bleed off speed.

Quote:

Originally Posted by R Leo

I flew into Kai Tak a few times and it was always scary knowing that if anything went wrong there's highrise buidlings on one side and HK harbor on the other. :eek: I think one MD-11 wasn't so lucky and slid into the harbor but floated somewhat due to the cabin pressurization. The new airport is much bigger (and hopefully safer for pilots and passengers). :)

Quote:

Originally Posted by dmorrison

For a crosswind my aircraft has a 30Kt "demonstrated" croswind. They design the aircraft with a rudder for 3 reasons. 1, you need a control on the yaw axis if you want complete control of the aircraft. 2, in a multi engine aircraft, you need the rudder to counteract the yaw tendency if you loose an engine. and 3, during a crosswind landing ( the wind is perpendicular to the runway) you use cross controls to align the aircraft with the runway.

Now in the New York airport area the flight patterns for all three major airports (LGA, EWR, JFK) is complicated. When the runways are changed at one airport it effects which runways can be used at the other airports due to the arriving and departing flight paths.

Dave

Incredible! So if it's this complicated to keep a big plane on course and oriented correctly, could somebody explain it to me again how a bunch of terrorists with no real flight experience, and with navigation transponders switched off, managed to hit three targets so accurately on 9-11? The Pentagon one is especially mind-boggling as it needed such a long run-in at nearly ground level. Who was doing such a good job at compensating for wind direction on that one? :confused:

Quote:

Originally Posted by coldwar

It wasn't windy that morning at the Pentagon..............I was on the roof of my building 5 minutes after that happened that morning 1/2 mile away ( I can see the pentagon from there). and there was no wind.

Quote:

Originally Posted by coldwar

Well, my take is as follows: the VAST majority of the time pilots get their landings right, so while it's very difficult and nerve-wracking, I'm sure, it's far from impossible. Plus, those 9/11 goofs weren't landing airplanes, they were crashing them, so whether they were "crabbed" approaches or not didn't much matter.

One of the pilots in this thread will chime in and set us straight, hopefully. They're the ones to ask. I can tell you about flap overspeed inspections and servicing landing gear snubbers, rigging flight control cables, etc..., but none of the exciting stuff. 8^)

Chris

Quote:

Originally Posted by coldwar

First, they did have real flight experience. Second, transponders are not used to navigate. Transponders allow an aircraft to show up on radar electronically; they are for the benefit of air traffic controllers, not the aircrew. Third, wind compensation during landing is quite different from wind compensation during other phases of flight. During landing, it is important that the longitudinal axis of the aircraft be parallel to the direction of travel (unless the aircraft is equipped with crosswind landing gear.) This is not necessary (or desirable) during other phases of flight.

Quote:

Originally Posted by cscmc1

I can tell you about flap overspeed inspections and servicing landing gear snubbers, rigging flight control cables, etc..., but none of the exciting stuff. 8^)

Chris

And it is because of people like you-attending to those mundane but important little details-that flying does not get exciting in a bad way. So don't think for one second that what you do is not important just because it is not all that exciting.