All, Yes the data burst are position fixes. SYSCOM uses a system called "flight-follow" to track each of the Helo's positions. 44.74 is used for SYSCOM - Medevac dispatch/coordination. 47.66 is called heli-med and is used by the Medic on the helicopter to consult/update patient status to/for the receiving facility. 123.05 is also commonly used for pilot to pilot coordination. Mike