Thank you for the info, i will try to post this, as you indicate too, in the mean time maybe you might come up with a answer to this frustrating fsx problem. many thanks. ken in Ro.
Default Fsx - inflight aircraft none alignment to any landing strip ?
   After many frustrating months of trying to eradicate a error in fsx, i am asking if possibly there is a answer or correction which can be applied.
   Problem is this, Whilst in flight ,and on approach, any aircraft takes on about 0.8 degrees of nose to the right and will not straighten up to a 360 line ( aircraft viewed from tail to nose ) When well under the 500ft and not far off touchdown, I find I have to apply full left rudder in a effort to keep the a/c on the strip line, however, at this point the aircraft does not accept any controller inputs to follow the runway but proceeds crabbing sideways up screen center. Should i not apply controller inputs when about to land the aircraft will put down to either the right or left of any strip and behave normally. There seems to be a inbuilt bias ? This error also is in being using fsx single or for a online flight.
  Trying to eradicate this problem , I have carried out the following :- tried fsx on 3 other pcs- have tried many new copies of fsx- fs x/de lux & gold, now have 10 copies !- This error happens with bare installed fsx and with or without addon scenery or aircraft. Tried installing with a new download of sp2 direct from ms and with ms acceleration, makes no difference. I ensure that all wx & wind sheer is turned off and set to 0 degrees- as manual wx keeps the weather to basic set up. All constants such as fsinn/fscuip4/ ukmil acars eliminated for each install tried- Prior to any install the hdd was cleared by a full format,to insure a clean install. Finally, built a brand new game pc for Fsx , new m/board supporting 8 ghig ram with 8 ghig shadowed- new hybrid hdd t1000by Seagate- Nvidia 560 gtx ti overclocked video card- New Pc is about a month old and using win 7- all Pc,s tried were with win7. First install of FSX still showed this error of aircraft none alignment. For some years been using the hotas twin and the t1600m by Thrustmaster- in the last 2 years , using X52 & X55 Controllers by Saitek.
   I am not new to flightsim, started armchair flying from when fs 2000 was first available, well used to the ins and outs of 2004 and i thought, FSX ? Funnily, this error only appeared about 18 months ago or maybe a little less. absolutely boffled, hoping for a fix to alleviate frustration.
Many thanks