A "flying" museum, like the Cold War Air Museum must exercise their aircraft, or at least the engines and systems on a regular basis.
Miguel for this outstanding picture. This picture and a number of others can be found as a desktop display on the "wallpapers" page at the museum main web site.
L-39's at the museum fly regularly.
MiG-23 instructor who is currently employed at a major flight training center at DFW. He is a big help with systems knowledge and practical experience in the MiG-23.
The massive R27-F2M engine in the MiG-23 makes a wonderful, unmistakable howl as the power comes on.
Mud Today! Just lots of happy noise from turbines turning and burning, consuming Jet-A.