What was found
IN FLIGHT AIRCRAFT COULD NOT PRESSURIZE IN AUTO OR MANUAL AFTER TAKEOFF. ALL DOOR LIGHTS WERE OUT, PACKS OPERATING NORMALLY, CARGO HEAT OUTFLOW VALVE HAD LITTLE EFFECT. FOUND L-1 DOOR BOTTOM HINGE BOLTS LOOSE, TOP GUST LOCK 'C' CLIP OFF. TIGHTENED BOLTS, RE-INSTALLED 'C' CLIP. (M)