'There are no ambulances out here': 911 calls detail horror of Asiana crash

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SAN FRANCISCO -- Shortly after Asiana Airlines Flight 214 crashed in San Francisco, passengers and witnesses pleaded with 911 responders to send help -- some frantically, some insistently.

"I'm reporting an airplane crash at SFO (San Francisco International Airport)," an early witness said in calls released by the California Highway Patrol.

"An airplane crash at SFO?" a dispatcher asked.

NTSB investigator Bill English and agency Chairwoman Deborah A.P. Hersman examine the wreckage of the Asiana Airlines jet that crashed Saturday in San Francisco. (National Transportation Safety Board / EPA / July 9, 2013)

"Yeah. We were hiking on a trail outside Pacifica and we heard a giant explosion and ... an airplane had crashed right there at SFO."

Another caller dialed 911, thinking the response was taking too long.

"We still don't see any firemen or anything," another witness said.

"We are responding, trust me," the operator responded.

Moments before, the Boeing 777's main landing gear slammed into a seawall between the airport and San Francisco Bay, spinning the aircraft 360 degrees as it broke into pieces and eventually caught fire.

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