ARMY UH-1V AND N7053R, A PIPER PA-28, COLLIDED IN MID AIR AT 700 FEET AGL. BOTH ACFT WERE IN LVL FLT. UH-1V WAS OPERATING ON A MEDICAL EVACUATION FLT WITH A CREW OF FOUR, ONE PATIENT AND TWO ATTENDANTS. THE UH-1V EXECUTED A SUCCESSFUL AUTOROTATION WITH SUBSTANTIAL DAMAGE AND NO INJURIES. THE PIPER CRASHED OUT OF CONTROL AFTER ITS RIGHT WING WAS CUT OFF BY THE HELICOPTER'S ROTOR BLADES. THE ARMY PILOTS REPORTED THAT WHEN THE PIPER WAS FIRST SIGHTED IT WAS 45 DEGREES TO THE RIGHT OF THEIR AIRCRAFT'S NOSE. THE HELICOPTER PILOT BEGAN A DIVING LEFT TURN BUT IT WAS TOO LATE. THE CO-PILOT STATED THAT THE PIPER EXECUTED AN EXTREMELY STEEP RIGHT TURN JUST BEFORE IMPACT. THE PILOT OF THE PIPER RECEIVED FATAL INJURIES. BOTH AIRCRAFT HAD THE FORWARD HALF OF THE ROTATING BEACONS COVERED. THE UH-1V WITH TAPE AND THE PIPER WITH BLACK PAINT.