What was found
AT FL90 WITH AUTOPILOT ENGAGED ACFT HAD AN OVERSPEED OF 10 KTS AT THE SAME TIME F/A CALLED SMOKE IN CABIN. HAD AN UNEVENTFUL LANDING, DECLARED AN EMERGENCY. INSPECTED ACFT EXTERIOR STRUCTURE, AFT FUSELAGE, BULKHEAD, STAB FITTINGS, JACKSCREW AREA NO DAMAGE FOUND NO BUCKLES OR CRACKS. EXAMINED ENGINE PANELS, DOORS AND LOWER SURFACES IAW MM 05-51-04-212-019 UNABLE TO DUPLICATE THE SMOKE IN CABIN. CHECKED BOTH PACK BAYS, ALL CARGO BAYS, LAVS, E/E COMPARTMENTS NO SIGNS OF HEAT. AIRCRAFT OK FOR SERVICE. (K)