SWISS diverted its Chicago to Zurich Boeing 777 to Lajes Airport in the Azores on Tuesday after crew reported an unidentified pungent, chemical-like odour in the economy cabin. The aircraft landed safely on Terceira Island, and the airline arranged a replacement service for passengers while the jet, registered HB-JNF, was taken out of service for inspection.
All 222 passengers and 16 crew members disembarked normally after the unscheduled landing. Five passengers and one crew member underwent precautionary medical checks after briefly reporting symptoms including eye irritation, nausea and headaches. The crew declared an emergency over the Atlantic to secure priority handling for flight LX9, which had departed from Chicago O’Hare for Zurich.
The source of the odour had not been identified when the aircraft arrived, and SWISS did not speculate before maintenance and safety checks were complete. The diversion disrupted the planned transatlantic rotation, with the return Zurich to Chicago service cancelled and a replacement aircraft sent from Zurich to bring passengers back later the same day.