The new Airbus A350-1000 has an inbuilt safety feature - it can automatically descend to a safe altitude if the flight crew are incapacitated because of depressurisation.
The loss of oxygen through rapid depressurisation has been responsible for several crashes and is one theory behind the disappearance of Malaysian Airlines' MH370 in 2014.
New A350-1000s are fitted with automated emergency descent, or AED, a system that engages the aircraft's autopilot function to automatically and quickly bring the aircraft to a lower, safer altitude in the event of in-flight cabin depressurisation.
The AED mode is triggered when the cabin pressure falls below a predetermined limit. After alerting the flight crew, the system engages the autopilot to bring the aircraft to a safe altitude if there is no crew reaction within 15 seconds.
The AED's use on the A350-1000 is the first application of its kind in a large commercial aircraft. Work is being done to fit the system to the earlier model A350-900.