An oxygen leak forced Lufthansa passengers heading to Brazil to take an 8-hour flight from Frankfurt to Frankfurt
- Lufthansa passengers spent more than eight hours in the air before returning to their original airport.
- Flight 500 had taken off from Frankfurt, Germany on December 27, and was on its way to Rio de Janeiro in Brazil when the crew detected a leak in the emergency oxygen system.
- The plane was off the coast of West Africa when the pilots decided to return to Germany as a "precautionary measure" - and the 373 passengers on board ended up back in Frankfurt more than eight hours later.
- A spokesperson for the German airline told aviation news website Simple Flying that the plane landed with no issues and passengers were put on another flight to Rio.
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Passengers on a Lufthansa flight from Frankfurt, Germany, ended up spending more than eight hours in the air before returning to the airport they took off from after a leak was detected in the plane's emergency oxygen system.
Lufthansa flight 500 took off from Frankfurt Airport at 10.55 p.m. on December 27 - an hour later than planned. But around four and a half hours into the flight to Brazil's Rio de Janeiro, the crew discovered the leak, aviation news website Simple Flying reported.
The pilots brought the airline's altitude down to 14,000 feet, where oxygen masks would not have to be used in the cabin if the cabin lost pressure, the airline told Simple Flying.
Once the pilots reached the altitude, they decided to fly the 373 passengers on board back to Frankfurt.
Passengers were then put on another flight to Rio de Janeiro.
Data from flight tracking website FlightRadar24 shows that the plane, a Boeing 747, had flown over Europe and was off the cost of the Western Sahara when it turned around.
The flight landed at 7.23 a.m. local time, according to FlightRadar24's data.
A Lufthansa spokesperson told Simple Flying that "the cockpit crew noticed a leakage in the Emergency Oxygen System for the passengers."
They said that there were no issues with the system during pre-flight checks: "This leakage only appeared during the flight, as it was already checked and approved okay before take-off."
The spokesperson for the German airline also noted that: "This system is used only in the rare case when the cabin pressurization system has a failure."
They said that the decision to turn back to Frankfurt was taken as a "precautionary measure."
"The passengers flew to Rio with a replacement aircraft, departing the same morning."
"The safety of this flight for passengers and crew was not in danger at any time."
The flight was Lufthansa's second similar incident in 10 days. On December 17, a New-York-bound flight took off from Frankfurt only to end up doing a u-turn over the Atlantic because of an issue with the plane's hydraulics, and ended up landing 85 miles away from Frankfurt Airport eight hours later.
A KLM flight in November also ended up spending hours in the air before returning to its original airport. The flight to Mexico ended up being an 11-hour flight from Amsterdam back to Amsterdam.