SAN FRANCISCO (KGO) -- Video, captured Thursday afternoon, showing smoke rising near an airplane.
United Airlines says there was no fire aboard an out-of-service aircraft.
The smoke began rising while the jet was being pushed outside a hangar where United performs maintenance work.
United also tells us smoke can rise from a plane due to residual oil in its engines.
A spokesman for SFO tells ABC7 News the incident is not affecting flights and that the airport is operating normally.