What was found
DURING THE CRUISE PHASE, CA + FO SMELLED A SMELL OF HOT PLASTIC OR A HOT IRON. BOTH PACKS WERE ON WITH ENGINE BLEED. AFTER LANDING FA'S IN FORWARD PART OF THE AIRCRAFT SMELLED AN ODOR OF UNKNOWN TYPE WITH BOTH PACKS ON APU BLEED. NO SMELL WAS NOTICED IN THE COCKPIT. PER TSM 05-50-00-810-831-A RAN BOTH ENGINES IAW AMM 71-00-00. OPERATED ENGINE 1 + 2 BLEED INDEPENTLY IAW AMM 36-11-00 AND APU IAW AMM 36-12-00. NO SMELLS NOTED DURING ISOLATION OF BLEED AIR SYSTEMS. HAD OUTBOUND CREW ONBOARD AIRCRAFT TO VERIFY NO SMELL IN AIRCRAFT. AIRCRAFT OK FOR CONITNUED SERVICE