What was found
CREW REPORTED- SHORTLY AFTER FLAP RETRACTION DURING AFTER TAKEOFF, CHECKLIST, COCKPIT CREW NOTED STRONG ORDER OF BURNING AND SMOKE IN THE COCKPIT. FLIGHT ATTENDANT, NEARLY SIMULTANEOUSLY, CALLED WITH THE REPORT OF SMOKE IN THE CABIN AND GRINDING NOISE MID CABIN BELOW DECK. DECLARED AN EMERGENCY, PERFORMED AIR RETURN. NO VISIBLE EVIDENCE OF SMOKE OR FIRE OUTSIDE OF AIRCRAFT WITH EMERGENCY TRUCKS FOLLOWING US IN. CORR ACTION- REMOVED DUAL HEAT EXCHANGER (PN: 815240-3 SN: 9806091) AND ACM (PN:815240-3 SN: 200104377) AND REPLACED DUAL HEAT EXCHANGER (PN: 815240-3 SN: 2008122597) AND ACM (PN:815240-3 SN: 2013100018). OPS CHK GOOD.