What happened
During the takeoff initial climb, the flight crew received an aural warning and observed that the number 2 smoke detector sensor light had illuminated in the cockpit. Following this alert, crew members noted a strong odor, described as similar to lacquer and varnish, emanating from the cargo area.
The investigation
Upon inspection, no evidence of an in-flight fire or any hazardous cargo spill was discovered within any cargo containers. Investigators identified wood panels located in cargo bin 5 that had been painted earlier on the same day. These panels featured a base coat (Kem-Flash E61A45) and a topcoat (Production Lacquer L61XX Lead-Free Custom).
The ramp agent responsible for loading the boxes into the cargo container reported no noticeable smells or fumes during the loading process. It was noted that painted panels may emit a paint-like odor during the curing process; however, once applied to the panels, the material is not considered a hazardous or flammable substance while in its curing stage.
Technical examination of the smoke detector (Part No. 7740-01, Serial No. 2024) determined that the unit was operating within the manufacturer's specified operational parameters.