Masks down. The cabin air got thinner.
BA295, 777-200ER G-VIIA, London to Chicago. Over Ireland cabin altitude hit 10,500 ft. Crew squawked 7700 and dropped to about 9,000 ft. Masks are down in the cabin.
Cabin altitude is not how high the jet is. It is how thin the air inside feels. On a 777 that normally stays at 8,000 ft or below while the aircraft is up near 37,000. Air comes in from the packs. Air goes out through the outflow valve. If more leaves than comes in, pressure drops and the air left inside gets thinner. That is 10,500.
A stuck outflow valve, a weak pack, or a real leak can all do it.
They are 30 tonnes over max landing weight and the crew said no means of jettison. So no dump.
— Fahad Naim (@Fahadnaimb) October 5, 2026
