I thought I knew all this and I have had it working previously! This is from a tutorial someone kindly put together a little while back for Cold and Dark startups "1. Switch both rotary selectors first to OFF then to NAV. When the IRS's have finished aligning the white ALIGN lights will begin flashing and you will have a FMC message saying "Enter IRS position". - Log on to the FMC on the CDU. This will get you to the IDENT page. On the lower right corner on the screen you will have "POS INIT" press the key next to it.2. Now you are on the POS INIT page. -Press CLR on the CDU a couple of times if you have any messages like "Enter IRS Position" and "Dual FMC restored" -Enter the ICAO designators for the airport you are at and click the key next to "Ref Airport" -Press Next page one time -You will see GPS R and GPS L and their positions. Click one of them and the position will be copied to the CDU scratchpad. -Press Prev page -You should see some square boxes below "SET IRS POS", click the key next to it on the right side. - Voila, you've set the aircrafts IRS position, the aircraft now now exactly where it is and the PFD and ND display come alive" As I said I did have this working previously when I followed these directions but now when I go to page 2 of the POS INIT section as described there is no position data next to GPS R or GPS L to paste into the SET IRS POS boxes on page 1. Assistance appreciated. Bruceb

I have had similar issues too. When I then look back at the IRS panel then the align lights are flashing. To get round this I just set the knobs to off again and then nav and usually they align properly 2nd (or 3rd) time of doing this.Like you say, I am sure I didn't have this issue before. Perhaps a hotfix3 issue?Graeme

First of all, you don't need to wait until align is complete, just after turnign both IRS in the NAV position go to the POS INIT page and wait few seconds just to let the IRS goes to the align mode after its initial bite tests.The position can be entered in many ways, manually by FMC or dirrectly on IRS panel (ISDU), or you can select an airport, or load the last position, or use the GPS position if satellites are already captured and GPS is ready (maybe it takes seconds to minutes to fix the position)I don't know if the pmdg simulates a delay in the GPS position detection.I'm loading FS right now to check this.I have GPS position just few seconds after power up, so I don't know why you don't have.

I heard somewhere that it takes some time for the GPS' to get a fix.

You can adjust the FMC to have realistic IRS alignment times or fake immediate alignment. Is that what you are discussing?

Thanks guys for your thoughts on this. There are now some more in depth tuts available on cold and dark starts I will have a look at those. Geez so much traffic on this forum I posted this less than 18 hours ago and it is down to page 4 (ie before this reply). Bruceb