What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS ON TAKEOFF, GEAR WOULD NOT RETRACT. RAN QRH, MANUAL EXTENSION DOOR VERIFIED CLOSED. RECYCLED GEAR RETRACTED. MAINTENANCE ACCOMPLISHED JACKING PROCEDURES IAW AMM 07-11-01, ACCOMPLISHED FIM 32-30-00 LANDING GEAR SYSTEM. OPS CHECKS NORMAL.