Max demonstrated crosswind definition please
Joined: Jul 2001
Posts: 486
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From: Belgium
"Demonstrated Crosswind Component" is NOT a limit unless it is listed in the limitations section of the POH. Since the certification must be flown 'as an average pilot', I have heard from reliable sources that the test pilot is not supposed to make any compensation for the crosswind and just plunks it down. A test of the landing gear strength really if you think about it. With good pilot skills you should be able to handle at least up to the DCC,
Joined: Jul 2008
Posts: 157
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From: Gone to my "Happy Place".
I can't seem to get a definitive answer to this. What does "Max demonstrated X-wind" actually mean?
Is it:
A) Most crosswind the aircraft has been landed in without kicking off drift (crab technique).
B) Most crosswind the aircraft has been landed in with drift kicked off (crab technique).
C) Most demonstrated using wing down method.
D) None of the above.
Is it:
A) Most crosswind the aircraft has been landed in without kicking off drift (crab technique).
B) Most crosswind the aircraft has been landed in with drift kicked off (crab technique).
C) Most demonstrated using wing down method.
D) None of the above.
....Using the maximum crosswind available during the certification phase for the aircraft, and, using the cross-wind landing technique as described in the Aircraft Flight Manual / FCOM.
Joined: Mar 2007
Posts: 420
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From: Right here
"Demonstrated Crosswind Component" is NOT a limit unless it is listed in the limitations section of the POH.
Joined: Jul 2011
Posts: 55
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From: Somewhere
The most x wind at a 90 degree angle that you can be assured of maintaining control-ability of the aircraft during take off and landing.
Certainly this number is well below the test pilot max numbers, given they have to assume a variety of pilot experience and ability, not to mention runway conditions, gusts, weight of aircraft, etc.
Certainly this number is well below the test pilot max numbers, given they have to assume a variety of pilot experience and ability, not to mention runway conditions, gusts, weight of aircraft, etc.
Joined: Dec 2002
Posts: 2,776
Likes: 351
From: UK
whenrealityhurts re “…you can be assured of maintaining control…”
There is no such assurance in a max demonstrated crosswind; you have no idea how much margin there is from a limit condition – primarily because the manufacturer has not been there.
In addition the test only assumes an ‘average’ pilot, a task which does not require undue skill or strength – experience and ability are not defined. How do pilots judge themselves before a max crosswind landing, how many times have they done it before, and what is their currency? Not known, and often misjudged.
Furthermore, the manufacturer does not have to consider runway conditions, but most do now publish guidance for wet conditions. The manufacturers’ tests may not record the type of runway surface – lateral friction characteristics; this might affect the ability to stay on the runway; as might tyre conditons.
Also, the manufacturer may measure the wind speed with a more sensitive system than used by ATC, thus the ‘tower’ wind might be differ, and in operations the accuracy of wind reporting can be ‘significantly’ different.
Then there are gusts … !
See #10 to #13.
There is no such assurance in a max demonstrated crosswind; you have no idea how much margin there is from a limit condition – primarily because the manufacturer has not been there.
In addition the test only assumes an ‘average’ pilot, a task which does not require undue skill or strength – experience and ability are not defined. How do pilots judge themselves before a max crosswind landing, how many times have they done it before, and what is their currency? Not known, and often misjudged.
Furthermore, the manufacturer does not have to consider runway conditions, but most do now publish guidance for wet conditions. The manufacturers’ tests may not record the type of runway surface – lateral friction characteristics; this might affect the ability to stay on the runway; as might tyre conditons.
Also, the manufacturer may measure the wind speed with a more sensitive system than used by ATC, thus the ‘tower’ wind might be differ, and in operations the accuracy of wind reporting can be ‘significantly’ different.
Then there are gusts … !
See #10 to #13.
Joined: Sep 2002
Posts: 2,188
Likes: 6
From: La Belle Province
wrh
please give a specific example in the post by safetypee where you note an error allowing you to make that statement. I'm curious.
and, by the way, max demonstrated means precisely that - the maximum demonstrated value. no margin, no pad, no "test pilot extra", nada.
please give a specific example in the post by safetypee where you note an error allowing you to make that statement. I'm curious.
and, by the way, max demonstrated means precisely that - the maximum demonstrated value. no margin, no pad, no "test pilot extra", nada.
