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News: Precision Simulator update 10.87 (15 September 2019) is now available

Author Topic: X-wind landings  (Read 476 times)

Simonijs

  • Join date: Oct 2014
  • Location: Amsterdam
  • Posts: 104
X-wind landings
« on: Thu, 22 Aug 2019 10:16 »
Morning,

Any thoughts on the first landing in this video (https://www.youtube.com/watch?v=JwgDl02z5Mc&t=58s)? The photographer makes a remark on the left wing outboard spoilers panels, that seem to be malfunctioning. If so, the left wing would still be producing more lift than the right wing.
Another three 747 aircraft are filmed as well, where you can clearly see these spoilers deflecting upwards.

A still of this video is now shown on FR24 as the photograph for PH-CKC.

Regards,
Simon

Hardy Heinlin

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  • Join date: May 2009
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    • Aerowinx
Re: X-wind landings
« Reply #1 on: Thu, 22 Aug 2019 11:42 »
Morning,

I think the spoilers #1 through #5 are down because the pilot is holding the right wing down with the aileron -- against the crosswind coming from the right. Not a malfunction, probably.


Regards,

|-|ardy

Jeroen Hoppenbrouwers

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  • Join date: May 2009
  • Location: KTMB
  • Posts: 3530
  • Hoppie designs avionics equipment for airliners.
    • http://www.hoppie.nl/
Re: X-wind landings
« Reply #2 on: Thu, 22 Aug 2019 11:57 »
The landing on the 7 minute mark; they hold the nose wheel off for quite a bit (intentionally or by accident). It seems that on main gear touchdown the outer spoilers deploy and only after firm nosewheel down, the inner spoilers. True?

Hoppie

Avi

  • Join date: May 2009
  • Location: LLBG
  • Posts: 760
Re: X-wind landings
« Reply #3 on: Thu, 22 Aug 2019 12:23 »
Definitely not a malfunction.

After landing the pilot turns the control wheel all the way to the right. You can see the right inboard aileron up before the aircraft crosses the photographer and both right ailerons fully up after it passes him.
This, as said, causes spoilers 1-5 go down but notice that spoiler 6 is still up (the control wheel doesn't affect it).

Cheers,
Avi Adin
LLBG

Hardy Heinlin

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    • Aerowinx
Re: X-wind landings
« Reply #4 on: Thu, 22 Aug 2019 15:11 »
The landing on the 7 minute mark; they hold the nose wheel off for quite a bit (intentionally or by accident). It seems that on main gear touchdown the outer spoilers deploy and only after firm nosewheel down, the inner spoilers. True?

That's a 748. It may be true on that type.


|-|ardy

localiser

  • Join date: Aug 2009
  • Posts: 39
Re: X-wind landings
« Reply #5 on: Tue, 10 Sep 2019 12:07 »
The 744 wing is really big and generates a lot of lift. In a crosswind, the into wind wing is generating enough lift to cause roll. Combined with decrabbing it can be a handful and you can really see the roll in your peripheral vision even when the wind isn’t that strong. More than smaller jets, the 744 needs into wind aileron on both take off and landing and frequently you have some crossed control in both phases which is then smoothly neutralised.

Interesting to see how close pods 3 and 4 get to the ground on the KL/MP landing.

Traffic

  • Join date: Apr 2019
  • Posts: 1
Re: X-wind landings
« Reply #6 on: Wed, 11 Sep 2019 10:33 »
It's not just the size of the wing, it's the sweep! Much more than on the 777 for example. This has the effect of lifting the upwind wing after takeoff and after touchdown when the spoilers come up, requiring more into wind aileron to keep the wings level. For the very reason localiser says: the engines are much closer to the ground than eg the 777. Maybe in the first 744 they applied too much into wind aileron: you apply enough to keep the wings level.

Re the nose being held up. Spoiler deployment also generates a pitch up so you're meant to fly the nose onto the ground and not hold it off. No idea what happened to them obvs and a rough old day!

Cheers

Robbie
« Last edit: Wed, 11 Sep 2019 10:43 by Traffic »