B-777 Landing Gear Question

jwp_145

jwp_145

GhostRider in the Sky
I've noticed in many videos of 777s in crosswind landings, and it appears to me like the gear tilts off of the vertical plane so that it is angled and not perpendicular to the ground.
[video=youtube;dd9NM9vsGD8]http://www.youtube.com/watch?v=dd9NM9vsGD8[/video]

It very well could be an optical illusion... I know that the gear trucks themselves are tilted in regard to the aircrafts longitudinal axis, with the front set of wheels sitting higher and the rear trails lower below the axle, and I know the reasons for that. So I'm thinking that the tires don't tilt left to right, and that the bogie itself tilting fore and aft is just causing an optical illusion.
However, what it looks like to me is that the wheels "lean in" to the crab before the pilot kicks the rudder to straighten her out.

Your thoughts?
 
This video shows it good too in the segments with the 777.

[video=metacafe;39256/crosswinds/]http://www.metacafe.com/watch/39256/crosswinds/[/video]

Looks like the bogies tilt sideways like a person standing on the ground leaning into the wind. I kow the B-52 bogies turn into the wind to align with the runway, but I cannot find any documentation about the 777.
 
Yes I know it is swept back... I said that in my original post... I'm trying to account for the side-to-side tilting, or at least the illusion thereof.
 
From what I've been told, the MD-80's (I'm assuming other MD-, DC-9, 717,) main gear actually pivot independently a few degrees side ways. Maybe the 777 does the same?
 
I don't know anything about the 777 main get but I do get to watch the 777-200 CAL flies all the time in EWR. When they push back often times they will spin the aircraft pivoting around one main. I am pretty sure the gear doesn't move and its just the massive tires flexing, but it is more than enough to give one the illusion that the whole gear truck moves
 
The main gear on the 777 do indeed "steer" when taxiing, (the rear set will castor actually, not really steering) but they also are locked straight on takeoff, you will actually get a "main gear not locked" EICAS warning and message if you push the power up for takeoff before rolling foreward far enough to allow them to straighten out and lock...don't ask me how I know!

BUT, they remain locked straight for landing, at least until the ground sensing squat switch tells the airplane it's on the ground and power is at idle, then they will castor again as you taxi in.

So if you are seeing them 'turned' on approach, something is wrong, or it's an optical illusion. On the preflight walk-around the main gear lockout bypass lever is something we have to check, to be sure they are not locked straight via the bypass lever being in the wrong possition.
 
Timbo said:
The main gear on the 777 do indeed "steer" when taxiing, (the rear set will castor actually, not really steering) but they also are locked straight on takeoff, you will actually get a "main gear not locked" EICAS warning and message if you push the power up for takeoff before rolling foreward far enough to allow them to straighten out and lock...don't ask me how I know!

BUT, they remain locked straight for landing, at least until the ground sensing squat switch tells the airplane it's on the ground and power is at idle, then they will castor again as you taxi in.

So if you are seeing them 'turned' on approach, something is wrong, or it's an optical illusion. On the preflight walk-around the main gear lockout bypass lever is something we have to check, to be sure they are not locked straight via the bypass lever being in the wrong possition.
Click to expand...

DUDE, You're ALIVE!!!
 
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