Crosswind from right. What rudder to use, and why?
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Crosswind from right. What rudder to use, and why?
Just been lurking around regarding how jets work and what not.
Came across a section that said when the a/c gets a x-wind from the right, the Pilot will use the left rudder.
I don't understand why this is though.
Somebody please explain?
Thank you.
Came across a section that said when the a/c gets a x-wind from the right, the Pilot will use the left rudder.
I don't understand why this is though.
Somebody please explain?
Thank you.
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To track the runway center line you will need to be crabbing with the nose towards the wind.
When you eventually want to land you want to be pointing (heading) as well as tracking the runway center line.
So on approach your heading will be to the right of the runway track and to get the aircraft to also point in that direction you will have to yaw the aircraft to the left which is the left rudder input
When you eventually want to land you want to be pointing (heading) as well as tracking the runway center line.
So on approach your heading will be to the right of the runway track and to get the aircraft to also point in that direction you will have to yaw the aircraft to the left which is the left rudder input
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There are many different techniques for xwind, there's not a lot of ground clearance with transport aircraft, holding a wing down like on a Cessna can get you into trouble. but you generally try to align the aircraft with the runway just before touchdown, with the wind from the right, the nose of the aircraft is pointed to the right, a few feet above the runway, you gently align the aircraft with the runway so there isn't any side load on the gear.
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Most transports want to weather vane, so the nose is trying to turn to the right due to the length of the fuselage, so Left rudder pressure during the TO run.
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Although most answers here are correct, referring to POSITIVE weathercocking, there are a few a/c types that display NEGATIVE weathercocking traits, where an oppsoite reaction is required.
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In the transition though it can be wise to use a little in to wind rudder to correct for the wind dragging you across the runway on the takeoff roll. I do mean a little though.
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Visualize the jet from top down, then visualize the crosswind from the right.
Now think which part of the aircraft offers the greatest amount of resistance to that wind. Correct, it's the bloody great big tail sticking up at the back end of the jet. The wind always tries to blow it around so that the tail is at the back and the nose is pointing into the wind. That's called "weathercocking".
With a right crosswind, that means the nose of the aircraft is trying to pull to the right on takeoff. Hence, you have to use left rudder to counteract it.
Now think which part of the aircraft offers the greatest amount of resistance to that wind. Correct, it's the bloody great big tail sticking up at the back end of the jet. The wind always tries to blow it around so that the tail is at the back and the nose is pointing into the wind. That's called "weathercocking".
With a right crosswind, that means the nose of the aircraft is trying to pull to the right on takeoff. Hence, you have to use left rudder to counteract it.
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referring to POSITIVE weathercocking, there are a few a/c types that display NEGATIVE weathercocking traits,
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Its all to do with the pivot point of the gear and which end of the aircraft produces most moment due to cross winds while on the ground.
But as with all these control inputs if you put the control input in to keep the picture correct you don't as such need to know which input to put in.
Just know what it should look like and deal with it if it doesn't look right.
But as with all these control inputs if you put the control input in to keep the picture correct you don't as such need to know which input to put in.
Just know what it should look like and deal with it if it doesn't look right.
