Aug 10
The McDonnell Douglas Model 199-VS100 was one of several variable-geometry (swing-wing) concepts studied internally during the company’s design work for the U.S. Air Force’s F-X (Fighter Experimental) program in the mid-1960s. The studies explored different configurations for achieving the required air-superiority performance. Ultimately, the heavier swing-wing designs were rejected in favor of a simpler fixed-wing configuration, which better met the USAF’s requirements. This approach evolved into the Model 199 proposal, selected in December 1969 and later developed into the F-15 Eagle.
