As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STUDENT PILOT STATED THAT RIGHT RUDDER PEDAL BROKE (ON START-UP). CHECKED TO FIND THE RIGHT PILOT'S MASTER CYLINDER HAD BROKEN. ALL HYDRAULIC FLUID WAS GONE AND RIGHT RUDDER PEDAL WAS AT 90 DEGREE ANGLE. THE PISTON ROD HAD COME OUT OF THE UNIT BECAUSE OF A BROKEN SNAP RING.