Dear Charlie, I had the same problem with disappearing arcs, but not with straight lines.I solved it adding a "break" command before the straight section in front of the arc and after the straight section following the arc, as follows:......SSL -10 10BREAKSSL -10 10SSL -12 12ARCSSL -15 15SSL -17 17BREAKSSL -17 17......I mean that even if You could draw a continious line that includes arcs, You'd better "BREAK" it before and after the arc section This way I solved the problem, but another way is to draw all the arcs, in a continous line, (without BREAK) all from right to left or all from left to right: this is not always possible, that is why I adopted the above mentionned way, by which does not matter which way you do it.Hope this helps.RegardsCekko

Thanks for your reply.I solved my fugitive lines problem. Seems I didn't check to see that my RefPoint was at the same altitude as my runways/taxiways. Boy, do I feel stupid!Regards,Charlie