[bouncing this to flightgear-devel from flightgear-flightmodel] David Megginson wrote: > Curtis L. Olson writes: > > [about sloping runways] > > > Depending on how much we trust the underlying DEM data, they may or > > may not be deliberate ... > > We shouldn't trust our DEM data at all even at 3 arcsec for > something as accurate as the slope of a runway. It would probably be > a better idea to flatten airports completely until we have a better > way to enter runway data.
True enough. Although the NASD database (for the US airports, at least) has elevations for both ends of the runway. So with a little work, we could get "straight" runways with the appropriate slope. That still doesn't work for some airports, like Catalina, that have a "hump" in the middle. Another option would be to "heuristically" trust the DEMs. That is, use the elevations as given, but (1) make sure the lateral axis is flat out to 100 ft. beyond the runway edge and (2) the longitudinal slope doesn't go beyond some theshold value. This could be done without too much difficulty -- just write code that pretends to be a land fill engineer and raises the land around the runway by the appropriate amount. Andy -- Andrew J. Ross NextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com "Men go crazy in conflagrations. They only get better one by one." - Sting (misquoted) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
