Hello Volonteer,I didn' t see your post ! Shame on me. That' s it, it works. I am very very glad...Many thanks for your precious help and many thanks to all the others for their comments trying to solve my INS unit misuse.Best regards,Guy

Thanks for the tips from me as well, Volonteer. I finally got the INS to align properly and drive the autopilot tonight using your steps, and once I figured out that the green "NAV" button below the VSI is the key to getting the INS and the AP to talk to each other. Thanks again also to the TMII team for this package - it's a blast!John Gilding