What was found
FLIGHT # 3723 MDT. UPON GEAR RETRACTION, THREE CAUTION LIGHTS VISIBLE AND RIGHT MAIN RED WARNING LIGHT VISIBLE. MOTORING SOUND NOTICED AND GEAR WOULD NOT RETRACT. IN TRANSIT LIGHT IN HANDLE. MAINTENANCE INSPECTED AND FOUND RIGHT NACELLE AFT ACCESS PANEL CRUSHED BETWEEN GEAR AND WHEEL PIN CUT-OUT PREVENTING RIGHT HAND GEAR FROM FULLY GOING INTO UPLOCK POSITION. PANEL REPLACED, GEAR RETRACTION TEST PROVED SATISFACTORY. AIRCRAFT RETURNED TO SERVICE.