Infographic: Some Boeing 777s grounded worldwide after engine failure Dozens of jets grounded following an engine failure on a United Airlines plane over Denver Published: February 22, 2021 21:44 Gulf News File photo: United Airlines flight UA328, carrying 231 passengers and 10 crew on board, returns to Denver International Airport with its starboard engine on fire after it called a Mayday alert, over Denver, Colorado. Image Credit: REUTERS Image Credit: Graphic News and Vijith Pulikkal/Gulf News