Good aft' simmersI have a long time wondered how to "re-align" (even if I know it s not possible in flight but it's a way to say so) the IRS, because while overflying non vor/dme's areas, position is updated by the IRS only (..no vor/dme, not even gps..), but if the "IRS will drift" option is selected in "767pic realism settings", the aircraft seems to drift until it totally losts its position and finaly gets into big troubles. Have you ever experienced that?How should we deal with it?Could someone send to me a little tutorial on oceaniq flights and the way to manipulate irs, if exists?thakns a lot to everyone for your help.MichaelParis, France

You won

"Have you ever experienced that?"The crew of a real b747-400 thought they could re-align the IRS's in flight.... They couldn't, not even using the GPS's... and had to dump lots of expensive fuel and return to their departure airport (Fortunately, they made it before the sun went down). Your only option is to use the ATT mode, but this won't help you navigate or use the autopilot. You must enter your magnetic heading on the FMC POS page at regular intervals to get a functioning compass card.Hope this helps.Cheers.Ian.P.S. Those of you with Lee's new TCAS/IVSI may notice that you can now use the IVSI with the (selected) IRS in ATT mode ;-)