A diminutiveflightattendant carried injured passengers piggyback to safety while two passengers worked to free another flightattendant pinned by an inflated emergency slide, all racing to escape Asiana Airlines Flight 214 minutes before it burst into flames.

Such quick-thinking heroics in the minutes after the plane's spectacular crash at San Francisco International Airport, combined with technological enhancements in recent years that have made jetliner accidents more survivable, likely prevented Saturday's disaster from being far more deadly, experts said.

The crash left pieces of the Boeing 777 strewn about the airfield and triggered a fire that burned away much of the plane's roof. Of the 307 passengers and crew aboard the flight from Seoul, two died, both 16-year-old girls from among a Chinese group of students and teachers headed to the U.S. for precollege exchange programs. More than 180 others were taken to hospitals with injuries. Two local hospitals listed 30 people still admitted as of Sunday afternoon, eight of which were in critical condition and two paralyzed.

The crash occurred with little warning for passengers. Eugene Anthony Rah, a frequent flier on Asiana who was sitting in business class, said he noticed the plane was approaching too low over San Francisco Bay, then he heard an engine noise that made him think the pilot was trying to gain elevation.

'We hit hard and bounced up. People were screaming,' he recalled. The plane seemed to careen out of control, skidding sideways, before stopping. Then there was 'total silence,' he said.

Mr. Rah noticed that an evacuation slide had inflated inside the plane, pinning a flightattendant against the interior cabin wall. He and another passenger tried to free the attendant, looking for something sharp with which to puncture the slide. Another passenger eventually found a way to let the air out of the slide. Mr. Rah said he has been in touch with the flight attendant's husband, who said she sustained serious injuries but is improving.

The captain soon started screaming on the loudspeaker for everyone to evacuate. As other passengers began exiting the plane and emergency crews arrived, Mr. Rah saw another flight attendant, whose name he gave as Jiyeon Kim, carrying injured passengers down the aisle to get them off the plane.

'She was a hero,' he said. 'This tiny, little girl was carrying people piggyback, running everywhere, with tears running down her face. She was crying, but she was still so calm and helping people.'

Meanwhile, San Francisco police officers at the scene had entered the plane from near the back and made their way to the front, amid worsening smoke, said Lyn Tomioka, deputy chief at the San Francisco Police Department. When they got to the front, male crew members trying to help passengers called out for knives, and the officers tossed their own knives to the men to help them cut seat belts off passengers who were struggling to get out, Ms. Tomioka said.

Aviation-safety experts said the human toll of the crash was almost certainly reduced by efforts of jet makers, airlines and regulators to reduce the deadliness of air accidents