What do you want to know about the United Airlines Flight UA770 Emergency Diversion today? The United Airlines Flight UA770, a Boeing 787‑9 Dreamliner carrying 257 passengers and 12 crew, declared a general emergency (squawk 7700) mid-flight from Barcelona to Chicago due to a cabin pressurization anomaly at approximately 37,000 ft. The pilots immediately diverted to London Heathrow—selected for its proximity and robust emergency infrastructure—landing safely on Runway 27R at around 4:55 PM BST. No oxygen masks were deployed, and there were no injuries.