What was found
F/D TEMP CONTROL ISSUE, RTFL. FOUND A MIX MANIFOLD FLOW STRAIGHTENER FIN LODGED IN THE FLIGHT DECK SUPPLY DUCT APPROX 21 INCHES DOWNSTREAM OF THE DUCT SPLIT, LT PACK TO MIX MANIFOLD. FIN WAS ACROSS THE DUCT BLOCKING APPROX 80 PERCENT. REMOVED FIN, OPERATED BOTH PACKS AND MARKED IMPROVEMENT IN FLOW OBSERVED IN FLIGHTDECK VS YESTERDAY WHERE FLOW WAS NONE. SATISFACTORY COOLING WAS OTBD SERVED. IN FLIGHT DECK.