I have created an airport using AFX and although the a/c moves from the parking spot up to take-off, it just sits there I have checked all the details of a similar airfield - but cannot for the life of me see where there is a difference I have created many AFX files before but this is really screwing with my brain cell(s) any clues will allow me to return to sanity Mike

Will you send it to me? I could check it for you.

I have created an airport using AFX and although the a/c moves from the parking spot up to take-off, it just sits there I have checked all the details of a similar airfield - but cannot for the life of me see where there is a difference I have created many AFX files before but this is really screwing with my brain cell(s) any clues will allow me to return to sanity Mike

You have to make sure the start point radius is within range of the hold short line, and of course you need a hold short line. I had this problem with Cloud 9 KMCO, there wasn't a hold short line for Runway 17R and Ai just entered the runway and sat there until they timed out and disappeared.

Now here is a surpriseIt all comes down to NOT using HOLD SHORT but use HOLD SHORT NO DRAWa simple answer but wow, what a long time to sort it out.thanks to all for respondingMike