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Old 03-07-2008 | 12:12 PM
  #46  
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Adolphus Coors
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Joined: Aug 2007
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From: 7ER B
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Originally Posted by BalloonChaser
I think you're missing the technique of "de-crab." The "de-crab" is also known as the "Crab and Kick" and basically the technique should be flown as - you fly the approach in a crab and "prior" to touchdown you input the rudder to align the longitudinal axis with the runway and the bank angle into the wind to prevent the drift. Not just align the longitudinal axis and maintain wings level and wait for impact! Effectively you transition from a "crab" to the "Side-slip" method; you're just doing it very late into the approach - Some pilot's will do it prior to the flare, some in the flare, some pretty much at touchdown (that variation WILL cause a sideload if you wait for impact.) But, the "De-crab" will not cause a side-load as you inferred it would, provided it's implemented prior to touchdown.
The whole reason to use the "de-crab" rather than the sideslip method is simply - drag (and the engine scraping the runway factor too!)
Keep in the mind, the side slip method called that because effectively that's what it is, a side slip - uncorrdinated flight creating more drag and you will typically need more power to maintain that attitude, however, if you fly the crab, you're flying coordinated until the last moment until you transition to the sideslip AND you won't have to reduce all that power you carried in the sideslip (which may cause you to float if you're late getting it reduced!) Anyway, just my two cents?

PS - The 737 does not have a castoring main gear for the one who asked? Not sure about whether it can take a landing in a crab anyway though?
Not according to our manuals. The de-crab method is aircraft parallel to center line with enough aileron to land with the wings level. It maybe different for your company or fleet. I have never seen anyone fly an approach in a side-slip which as you stated would require more power. I have seen the majority of the pilots I fly with apply a side-slip just prior to the flare which does not require more power. Your de-crab method is what we call the side-slip method.

I'm pretty sure I'm not "missing the technique of the de-crab," as yoy say.

Last edited by Adolphus Coors; 03-07-2008 at 12:25 PM.
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