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dmorrison · #9 03-22-2005, 09:23 PM

Quote:

Originally Posted by Brian Carlton

One of the scariest things I witnessed was a DC-8 (IIRC) landing in St. Lucia.

Same deal, one runway and the need to use the controls to hold the aircraft parallel to the runway in a crosswind.

However, this fellow chose to use a crabbed approach for whatever reason and he held it all the way to touchdown. The aircraft instantly twists and the tires align themselves with the direction of flight (down the runway). It had to be just brutal on the gear, and, I'm sure the passengers didn't appreciate it one bit.

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%27Obrvat%20747%25%27%29%20NAQ%20%28cynpr%20%3D%20%27Uba t%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%20gnxra%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%27Obrvat%20747%25%27%29%20NAQ%20%28cynpr%20%3D%20%27Uba t%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