British Airways jet turn back after both pilots report feeling unwell IMAGE SOURCE: Open.edu

Not long after take-off a British Airways flight was forced to return to Heathrow after both pilots reported feeling “light headed” and needed to be fitted with oxygen masks to land the plane safely.

The Air Accident Investigation Branch has been investigating the incident which involved flight A321 from London to Glasgow on the 20 December, the Guardian reported.

A British Airways spokesperson said that both pilots on board Airbus A321 reported being “unwell” and as a precaution they fitted oxygen masks and followed instruction to turn the aircraft back to Heathrow.

"The pilots reported feeling light-headed so, as a precaution and following normal procedure, put on their oxygen masks,” a British Airways statement read.

"Our pilots are highly trained to deal with such circumstances. The aircraft landed safely and customers continued their journey after a short delay," the statement continued.

A person claiming to have been a passenger on the aircraft posted on a professional pilot’s website their account of what happened saying "a very abrupt and panicked message" calling for a senior flight attendant to the flight deck had come over the PA system.

"At this point there were defined worried faces across all of attendants, next thing was an o2 cylinder and mask taken forward and we were heading back to Heathrow at great speed,” the passengers reported.

"No announcement for a long time then the expected technical problem line was posted to all.