As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX/JFK - FLT 290 - AIR TURNBACK, PANEL 911KT LOCATED ON TOP OF LT WING NR 1 ENGINE PYLON DEPARTED AIRCRAFT DURING TAKEOFF. PANEL WAS IMPROPERLY SECURED. AIRCRAFT RETURNED TO PHX LANDING UNEVENTFULLY. OVER WEIGHT LANDING INSPECTION C/W. PANEL REPLACED AND AIRCRAFT RETURNED TO SERVICE. (X)