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HeathrowAirport
8th Jan 2009, 21:21
Hello,

First off this is a General Question but can help within a Flight Sim Enviroment and also will help in my studies for my PPL.

Less of the explaining of why I am flying UAE1 into Heathrow in flight Sim this Sunday but the winds forecast are Winds 360 at 13 Gusting 37, later changing to Winds 360 at 18 gusting 44mph.

Thats probably just averages but forecast by the met office and I was wondering what direction I trim the rudder and how much? Thats an extreme crosswind and I have not experienced that strength. I use Active sky so its nearly realistic so a bit of Professional Aviation help would be useful.

Regards,

R..

Eff-Ohhh
8th Jan 2009, 22:09
For the purposes of your PPL and subsequent studies...

No rudder trim should be used for normal cross wind landings for a mult-engined jet. For such aircraft rudder trim is used to balance thrust asymmetry as in the case of "one engine inoperative" situations, or very fine adjustments to compensate for small airframe aerodynamic variances at different speeds.

On a propeller aircraft (particularly single engined aircraft) any time you change the thrust or propeller pitch, a rudder trim adjustment will need to be made.

Whether it is a cross wind or not doesn't make any difference to "rudder trim" required because as far as the aircraft is concerned it is going through the air in a straight line (no cross wind). It is only when the wheels meet the runway is the cross wind a factor, and the technique for the cross wind landing in a large airliner (particularly with a low wing) is to flare, then just before touch down gently apply rudder towards the direction of the runway alignment, using enough aileron to keep the windward wing from lifting (much more marked in a swept wing aircraft). Then touch down fast before you drift off the centreline.

Good luck with the PPL studies, and subsequent ATPL studies if you so decide.

HeathrowAirport
9th Jan 2009, 17:11
Eff-Ohhh,

Thanks very much. So in the case of Sundays winds I use more rudder and also would I plant it on slightly to the left or right, depending on X-wind component direction, of the Runway Centerline? And do i point the wing into the crosswind?

And thanks, I hope your luck gets my dream :)

Regards,

R..