Swiss International Air Lines: earbud case sparks smoke scare on Zurich–New York flight

A simple earbud case became wedged inside a seat.

On Monday 27 July 2026, a Swiss International Air Lines flight from Zurich to New York suffered a frightening incident at cruising altitude. As the Airbus A330, carrying 208 passengers, flew calmly at 32,000 feet above the Atlantic, thick smoke suddenly began filling the front section of business class.

With the precise cause still unknown, the pilots took no chances. They promptly began a dramatic descent, losing more than 22,000 feet (around 6,700 metres) in just 10 minutes, before diverting to Bangor International Airport in Maine, United States. The aircraft landed safely, and all 208 passengers were looked after without injury.

The culprit identified

Following a detailed inspection by the airline's technicians, the source of the suspicious smoke was quickly established. It was a small wireless-earbud charging case with a power-bank function.

The device had accidentally slipped into a gap in the seat, where it became trapped and damaged. The pressure caused its small lithium battery to overheat, producing heavy smoke in the cabin. The episode underlines how these everyday gadgets can become hazardous when they are knocked, crushed or handled improperly.

Swiss International Air Lines safety rules to remember

“It was ‘only’ a small charging case with a relatively low battery capacity. ‘Proper’ power banks have a considerably higher capacity. In such circumstances, damage or a malfunction may have far more serious consequences,” the airline said in a statement.

“Passengers may still bring power banks on board, but no more than two per person,” it added, specifying that the device must not be used during the flight. It must also be kept “on the passenger’s person, in the seat pocket or in hand luggage stowed beneath the seat”, and is strictly prohibited in checked baggage or overhead lockers.

It is worth noting that if a device overheats, is damaged or is lost beneath a seat, travellers must notify cabin crew immediately, as they have special fire-resistant bags designed to contain any danger.