San Francisco, CA — Video footage emerged Wednesday of the out-of-control sightseeing bus that crashed last week in San Francisco’s Union Square, critically injuring several people after it careened through street barricades and plowed into construction scaffolding. In the video, the double-decker, open-air bus, operated by City Sightseeing, is shown barreling down Post Street on Friday just before 4 p.m. as frightened pedestrians jump back from the runaway coach. The bus can be seen crashing through a number of orange, water-filled barricades in what the driver’s attorney says was a desperate attempt to stop the bus after a small explosion crippled the vehicle’s hydraulic brake system. […] the bus was not on an official listing of the company’s fleet of 27 vehicles, said the California Public Utilities Commission, which regulates tour buses. […] CHP officials said the agency had not looked at the bus, even though state rules require tour operators to notify the utilities commission within 10 days of adding a vehicle to a fleet, allowing the CHP to do an inspection.