The flight, which was bound for Glasgow, was climbing at 20,00 feet when the pilot and co-pilot reported feeling light headed, prompting cabin attendants to rush to their aid with oxygen masks. 

“I was on the London to Glasgow flight yesterday, departed Heathrow at 4pm-ish, got airborne, at approx 20mins into the flight a very abrupt and panicked message came over the PA from the pilot,” a passenger on the flight said on a professional pilots website.  

The flight was turned around and the passengers told this was because of a technical fault, however they were greeted at Heathrow airport by a fire crew and paramedics, who were the first on board the plane.

“Still being fed the tech fault line but the first onboard were paramedics???” the passenger wrote. 

“It later transpires that both pilots became lightheaded/dizzy/unwell at the same time, in my book that’s serious.”

A BA spokesman said: “The pilots reported feeling lightheaded so, as a precaution and following normal procedure, put on their oxygen masks.

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

The incident is being investigated by the Air Accident Investigation Branch.

Photo: Getty.