What was found
AFTER TAKEOFF AND GEAR RETRACTION, GEAR 'UNSAFE' LIGHT STAYED ON. SELECTOR INDICATED THAT THE RIGHT MLG DOOR WAS NOT LATCHED. ON THE THIRD GEAR RECYCLE 'UNSAFE' LIGHT EXTINGUISHED AND GEAR DOOR INDICATED UP AND LOCKED. FOUND LOOSE STRIKER PLATE AT RIGHT MLG DOOR PROXIMITY SWITCH. TIGHTENED STRIKER. MLG GEAR UPLATCH AND DOOR CLOSED PROXIMITY SWITCH TEST OPS CHECKED GOOD IAW DC 8 MM CHAPTER 32.