A Boeing 777-200ER operating British Airways flight BA295 from London-Heathrow to Chicago performed an emergency descent over the Irish Sea on Monday, October 5, 2026, with oxygen masks deployed for passengers. The flight had departed from London-Heathrow at 12:15 local time and was en route across the Atlantic when the pilots initiated an emergency descent. During the descent, the crew activated transponder code 7700, a signal used to indicate a general emergency to air traffic control. The aircraft was at an altitude of 36,000 feet, about 40 nautical miles south of Dublin, when the pilots began descending due to a loss of cabin pressure. Oxygen masks were deployed for passengers, and the plane stabilized at approximately 9,000 feet seven minutes later. The emergency descent involved a decrease in altitude of 27,000 feet, or about 8,200 meters, with an average descent rate of nearly 3,800 feet per minute. According to available information, the pilots initiated the descent intentionally, and the aircraft did not experience a free fall or loss of control. In cases of cabin pressure loss, the objective is to quickly reach an altitude where the outside air is breathable without the need for additional oxygen. The masks protect passengers during this transition to a safe altitude. Passenger Tom Nicholls reported that the plane changed its attitude during the descent, but he did not feel it was descending rapidly. He mentioned that the captain announced the aircraft had descended below 10,000 feet, and the oxygen masks were no longer needed. After stabilizing at a lower altitude, the Boeing 777 turned back and extended its flight off the southwest coast of Britain, particularly in the Bristol Channel area. The plane finally landed at Heathrow at 17:00 local time, nearly five hours after its departure. Sources indicate that the aircraft had reduced its fuel load before returning. The Mirror reports that the plane consumed fuel while waiting off the Welsh coast, and AeroInside mentions fuel jettisoning in the Cardiff area. These details have not been officially confirmed by British Airways in the statements cited by the media. The waiting period before returning to Heathrow was due to a constraint specific to long-haul flights: an aircraft departing for an Atlantic crossing carries a significant amount of fuel, and an early return may require reducing the plane's weight before landing. The observed flight paths are consistent with the preparation needed to return to Heathrow after the emergency descent. British Airways confirmed the return of the aircraft but remained cautious about the cause of the event. "The safety of our customers and our crew is always our absolute priority, and the plane landed safely after our highly qualified pilots returned to Heathrow following a technical issue," said a company spokesperson. "The customers disembarked normally and our teams are working to allow them to continue their journey as quickly as possible," added British Airways. A passenger interviewed by a British daily newspaper indicated that he had been rebooked on a flight scheduled for the following day.