British Airways flight from London Heathrow declares emergency after plunging 28,000ft

The terrifying ordeal occurred around 34 minutes into the near-nine-hour flight.

A British Airways flight was forced to make an emergency landing after dropping thousands of feet shortly after take-off.

The aircraft, en route from London Heathrow to Chicago, was forced to declare an emergency and abandon its transatlantic route after plunging from 37,000 to roughly 9,000 feet.

The terrifying ordeal occurred over Irish waters, around 34 minutes into the near-nine-hour flight.

The Boeing 777-200ER departed Heathrow Terminal 5 at 11.15am on Monday, bound for Chicago O'Hare.

It comes just days after a Flydubai flight bound for Tel Aviv was forced to make an emergency landing in Saudi Arabia, after the pilot nosedived the aircraft and repeatedly stabbed his co-pilot in an attempted hijacking.

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By 11.50am, the aircraft had reached its cruising altitude of 36,000 feet when it suddenly began to descend, dropping to just 9,000 feet within seven minutes, Flightradar24 data shows.

At 12.10pm, the plane made a sharp U-turn and was redirected to Heathrow.

The exact cause of the sudden descent remains unconfirmed, but British Airways said the plane turned around after a "technical issue".

Footage circulating online shows oxygen masks hanging from the ceiling.

The plane spent around four hours zigzagging over the Bristol Channel, before landing back at Heathrow at just after 5pm.

A spokesperson for the flag carrier airline said: “The safety of our customers and crew is always our top priority, and the aircraft landed safely after our highly trained pilots returned to Heathrow following a technical issue.

“Customers disembarked the aircraft normally and our teams are working to get their travel plans back on track as quickly as possible.”

The aircraft, registration G-VIIA, is reportedly the oldest in British Airways’ fleet, having been delivered in July 1997.