The designation of Rwy 25L with part of the runway as 26L was an experimental designation for higher runway usage.
The plan was that small aircraft could land on 25L while other aircraft were taking off on 26L at the same time. This would effectively allow the runway to almost double its capacity.
There was also a test of aircraft landing long on 26L while other aircraft were lining up to takeoff on 25L. They could start their takeoff roll as the 26L aircraft touched down. This would increase the runway capacity by about 25-30%.
This layout of the airport was in effect in the fall of 2002 - which is when FS2004 airports were set. The designations were active in April 2005 when FSX airports were set. Google Earth shows this runway configuration in the May 31, 2000 view - up thru 2005 images. The latest image - 12/31/2008 - shows the Rwy 26L markings are no longer on the 25L runway.
The end result of the test was that the use of one runway with two designations was not really effective in increasing runway capacity, and greatly increased the potential for conflicts.
Flight Simulator cannot replicate the runway markings when two runways are placed together. The draw engine isn't designed for the literally "One in the World" configuration.
And of course, hundreds of people has viewed this setup of EDDF in FS2004 and FSX as a 'bug', or sloppy work on the part of the ACES development team - not realizing it was actually a real world configuration.
Last edited by ReggieF5421; 07-11-2012 at 02:05 PM.
@ PawPaw's house - near KADS, Addison, Texas, USA