What was found
(CAN) DURING FLIGHT TEST AFTER MAINTENANCE THE LANDING GEAR WOULD NOT FULLY RETRACT AND THE C/B DEACTIVATED THE DRIVE. THE EMERGENCY EXTENSION LEVER WAS FOUND TO BE ENGAGED, THE LEVER WAS DISENGAGED THE LANDING GEAR WAS SELECTED TO DOWN AND C/B WAS RESET. THE LANDING GEAR EXTENDED AND LOCKED DOWN THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED THE LANDING GEAR AND RETRACTION SYSTEM AND REPLACED THE GEARBOX ASSEMBLY.