What was found
(CAN) A/C HAS 15120.6 T.AT. TIME ON PART UNKNOWN, MAY BE ORIG. UPON TAXI TO HOLD LINE, PILOT TURNED FULL LEFT THEN FULL RIGHT TO CHECK BRAKES & STEERING. PILOT APPLIED FULL POWER AFTER T/O CLEARENCE & HAD TO KEEP GREATER THAN NORMAL RIGHT RUDDER TO KEEP A/C STRAIGHT. WHEELS LEFT GROUND AT 70K A/C IMMEDIATLY YAWED HARD LEFT. PILOT PUT IN FULL RIGHT RUDDER & AILERON TO COMBAT, RUDDER STAYED JAMMED HARD LEFT. A/C LANDED ON GRASS & HIT DITCH CAUSING EXTENSIVE ENGINE, PROP & FUSELAGE DAMAGE. AME & TSB DISCOVERED THAT RT STEERING PUSH-PULL ROD COULD HAVE JAMMED IN SHORTENED POS&AS OLEO EXTENDED, IT PULLED LT RUDDER PEDAL IN, IN TURN DEFLECTING RUDDER FULL LEFT. WASHER THAT USUALLY SLIDES FREELY IN S TEERING TUBE