A SWISS flight from Zurich to Porto was forced to make an emergency landing back in the Swiss city after an unusual smell was detected by the pilots. This is the second time such an incident has occurred at the airline, with SWISS still unwilling to say what causes the odour.

SWISS flight to Porto makes emergency landing due to smell

On October 10 at 5.13pm, LX2064 took off from Zurich Airport and headed for Porto, Portugal. The plane, an Airbus A220-300 series, had 141 passengers on board.

Unfortunately, almost as soon as the wheels had left the ground, the two pilots noticed a bad smell coming from the cockpit. SWISS were unable to confirm whether the smell was the same as the one detected by pilots on a flight in August, which was forced to divert to Frankfurt due to the bad odour.

Emergency landing in Zurich went smoothly, SWISS confirms

For "safety reasons," the pilots in the cockpit decided to make an emergency landing back in Zurich. According to Flightradar24, reported by 20 minuten, the local fire brigade and other emergency services were stationed near the runway, ready to act if something should go wrong. After just one hour in the air, the plane safely touched down back at the airport. The passengers on board were all rebooked on other connections to Porto.

Speaking to 20 minuten, a SWISS spokesperson confirmed that the plane was indeed forced to make an emergency landing, but that it was smooth and touched down without incident. While the international company could not explain the exact cause of the smell, or the nature of the smell itself, the pilots had been forced to make the landing because of a “technical defect.”