WATCH: A United Airlines Boeing 757-200 lost a main landing gear wheel shortly after taking off from Los Angeles on Monday. Despite the potentially hazardous situation, the aircraft, carrying 174 passengers and 7 crewmembers, successfully landed in Denver without any reported injuries. The wheel has been recovered in Los Angeles, and the airline is investigating the cause. This marks the second time this year United Airlines has experienced a similar incident, the previous one involving a B777-2