What was found
THE PILOT STARTED THE AIRCRAFT ENGINE, THE AIRCRAFT STARTED TO ROLL, AT WHICH TIME THE PILOT APPLIED THE BRAKES. THE LEFT BRAKE WAS OPERATIONAL BUT THE RIGHT WAS FLAT. THIS CAUSED THE AIRCRAFT TO SWERVE TO THE LEFT HITTING A CESSNA CARAVAN DAMAGING BOTH AIRCRAFT. THE BRAKE SYSTEM WAS INSPECTED, RESERVOIR FOUND TO BE FULL, NO LEAKS FOUND. SUSPECT AIR IN THE BRAKE SYSTEM.