Why do pilots deflect the rudder?

Question

Why do some airline pilots deflect the rudders of aircraft (the rudder is pointed outward almost the entire time the plane is at the gate) when parked/waiting?

Answer 1

It was probably being deflected by wind.  When there is no hydraulic pressure on the flight controls, they tend to kind of flap in the breeze.  A steady crosswind will deflect the rudder fully to one side or the other.

Answer 2

You'll usually see this on a windy day.  The wind will blow the rudder to the side when there's no hydraulic pressure.  If there is a tailwind it'll usually deflect the elevator up.  If you can see both left and right ailerons, they'll be drooping.  As soon as they turn on the hydraulic pumps on just prior to departing, all the flight surfaces will all return to the neutral position.  

Avio, when a plane is taxiing into a gate, they steer using the tiller not the rudder pedals and the tiller is not in anyway connected to the rudder.  If it was towed to the gate, the steering bypass pin will have been installed and will disconnect the rudder pedals from the nose gear steering.

Answer 3

Probably to test that they are working - part of the pre-flight check.

Answer 4

Part of the preflight checklist to check to see if all flight controls are "free and correct"

Some Airplane have control surface pins that lock the control surfaces and landing gear on the ground to keep them from moving when the wind blows and to prevent gear collapses while on the ground,  and this is to ensure that control surface is not pinned and no mechincal problems are present..

Answer 5

It reflects the way the nosewheel steering was used while pulling the airplane up to the jetway.  It just stays the way it ended up.

The "controls free and correct" test as described above is correct, but that test is not performed until after leaving the gate for takeoff.