What was found
DURING TAKEOFF ROLL APPROXIMATELY 50 TO 60 KNOTS, AIRCRAFT FELT LIKE IT NEEDED MORE NOSE DOWN TRIM. A UNIT OF TRIM WAS ADDED, AS AIRSPEED INCREASED MORE PRESSURE WAS NEEDED, MORE THAN NORMAL. IT FELT EXTREMELY TAIL HEAVY AND TAKEOFF WAS ABORTED. *S/D* LOAD IN AFT CARGO COMPARTMENT WAS WITHIN LIMITS. CHECKED ELEVATOR AND STABILIZER RIG, BOTH WITHIN LIMITS. TEST FLIGHT WAS MADE AND OPERATION WAS NORMAL.