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Tallguy

how does one crab with the 737?

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...or anyplane for that matter, but since I only fly the NGX I'd like to know this.Does one turn the nose into the wind with the rudder and steer the plane via the yoke to the runway or vice versa? Does this also work in the NGX with the autorudder turned off?

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A crab is just a different fuselage angle to runway heading in coordinated flight to adjust for crosswind component on approach, but, if your talking about a slip then......You cross control the ailerons and rudder. So, Left sustained rudder and Right Sustained Aileron, or visa versa.It works well on the NGX, bleeds speed and increases descent rate for those times when your late and your approach is hot and or high.Not sure if a slip is certified for the 737's, LOL, but who cares it's fun. :)JB

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As JB inferred, I don't think slips are permitted in the most modern commercial airliners (either due to mfr limitations or SOP). But, why not.

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I don't think that he is talking about slipping a 737. A slip is not a very known maneuver under Flight simmers, so let's assume he's talking about normal crosswind landings.For those you would have to turn the aircraft into the wind using a normal bank. You'll then fly the aircraft until you're almost down and just in the last moment you'll use the rudder to turn the aircraft's nose back into the runway heading. But you should ask you FCTM for that, there's a chapter about crosswind operations in it I think.


Greetings from the 737 flightdeck!

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Maybe he is just talking about a crab.But for shits and giggles if he is talking about a slip to wheels down (Wing low crosswind landing) then you drop the wing thats on the crosswind side into the wind and push opposite rudder to maintain aircraft heading to runway heading. So your low wing is fighting the crosswind component and your rudder is keeping the nose straight down the runway. This landing is a slip to wheels down and will avoid sideloading the gear in a heavy crosswind. I know this is not permitted in large aircraft with low wings as too low of a wing will cause it to strike the runway. The Crab to rudder is usually used in large aircraft as the inertia of the aircraft track will keep it traveling straight down the runway and a quick kick of rudder will straighten the gear out to prevent sideloading. If you kick the rudder too early the aircraft will drift off the centerline.Fun stuff.JB

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I'm actually noticing the exact oposite when slipping. Always when I slip my aircraft wants to go upwards a little. Also when I decrab, which is performed in pretty much the same way as a slip (crosscontrols), my aircraft wants to go upwards. So I have to account for that by not really pulling back because the decrab will make my plane flare also. Quite difficult to master this imo.

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There is a reason that not a single pilot in the world ever started flying in a jet.... basics 101 :-)


Jay

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If you have any of the RealAir or A2A addons, practice your slips in them. They seemed to have set up the Flight Dynamics to represent the effects of a slip pretty well. The Scout or the Cub comes to mind.Heres an old video, where I'm trying to get the J41 into a little strip. You don't have to watch the whole video, you can see the slip to descend and slow over some trees at frame marker 5:00. Almost held the slip all the way to touchdown.

JB

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Check out youtube for 'scary landings', you'll see pilots doing all of the above to get it on the ground, and some that choose discretion over valour :)Kai Tak is a favorite and there's a KLM 747 at Kai Tak that is 'the' classic imho.

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I don't think that he is talking about slipping a 737. A slip is not a very known maneuver under Flight simmers, so let's assume he's talking about normal crosswind landings.For those you would have to turn the aircraft into the wind using a normal bank
Right. But the first technique the OP described was a slip.And what?Make it simple guys:A crab is when wings are LEVEL. Nose of the aircraft "towards" the wind. Longitudinal axis of the aircraft is not parallel to the direction of flight over the ground.Essentially you are "looking towards the side window" towards the direction of the wind.

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This thread just reminded me of something from a few years ago. I was a passenger on a USAir express flight to Tampa on a Beechcraft 1900. The wind was something like 220/25, Tampa was obviously landing to the south (one of the 18's). The cockpit door was open (good old days before 9/11) so we could see the flight deck and out the cockpit windows. On final approach, the plane's nose was pointing off to the right, the runway ahead of us, but visable from the side window. This elderly couple was sitting in front of me. The Beech has 1x1 seating, so they were "aisles across". I was laughing, as this couple looked outside, saw the plane pointed to the right, saw the runway to the side, looked at each other, looked outside again, looked at each other again, and then held hands (for what they probably thought was going to be the last time). Of course, the pilot de-crabbed and landed perfectly. I still recall the terrified looks on their faces!!

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I'm actually noticing the exact oposite when slipping. Always when I slip my aircraft wants to go upwards a little. Also when I decrab, which is performed in pretty much the same way as a slip (crosscontrols), my aircraft wants to go upwards. So I have to account for that by not really pulling back because the decrab will make my plane flare also. Quite difficult to master this imo.
In real world you would even have to pull the nose up during a slip, but if you don't the nose will dive. At least that's how an ASK21 is behaving. One of the Bugs in FSX is that you can't really do a slip well, because in FSX you can't pull the nose up without loosing speed (and stalling after a while) which is not realistic. In reallity you wouldn't even have a speed indication in a slip...

Greetings from the 737 flightdeck!

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Check out youtube for 'scary landings', you'll see pilots doing all of the above to get it on the ground, and some that choose discretion over valour :)Kai Tak is a favorite and there's a KLM 747 at Kai Tak that is 'the' classic imho.
The one in the water? :Whistle:Bert Van Bulck

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Here's one of my favorite crosswind landings ever, landing at KPHL. Notice the FPV (Flight Path Vector) is embedded on the speed tape, was quite the challenge to keep my eyes on it during the final moment before flare!

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...or anyplane for that matter, but since I only fly the NGX I'd like to know this.Does one turn the nose into the wind with the rudder and steer the plane via the yoke to the runway or vice versa? Does this also work in the NGX with the autorudder turned off?
You don't have to do anything! Especially if you are on the glideslope with autopilot on, in approach mode.If you are heading toward the runaway, on the correct heading, in a crosswind... then the aircraft will already be crabbed.If you're nose were pointing toward the runway, on the correct heading, in a crosswind, you would be drifting downwind, away from the runway. So you would obviously steer toward the runway, and thus be crabbed.When you get to the flare, power back at 30 feet, raise the nose a few degrees, while simultaneously applying rudder to decrab. Aileron may be required to keep the wings level.If the iarcaft is on the right approcah heading, then the crab is a natural consequnce of a crosswind.Press the FPV button in the cruise with AP on, and look on the PFD, or look at the Hud... you will see the aircraft crabbed in a crosswind.

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