10 USC 8750 - Airmans Medal: award; limitations
(a)
(1) The President may award a decoration called the Airmans Medal, of appropriate design with accompanying ribbon, to any person who, while serving in any capacity with the Air Force, distinguishes himself by heroism not involving actual conflict with an enemy.
(b) Not more than one Airmans Medal may be awarded to a person. However, for each succeeding act that would otherwise justify the award of such a medal, the President may award a suitable bar or other device to be worn as he directs.