CLARENCE CENTER, New York (CNN)  -- The pilots of a commuter airliner that crashed late Thursday about 6 miles from a Buffalo, New York, airport discussed "significant ice buildup" on the plane's wings and windshields before the plane plunged to the ground, killing 50.





Only a few pieces of the Continental Connection Dash 8 turboprop were recognizable after the crash.





Continental Connection Flight 3407 was en route from Newark, New Jersey, to Buffalo Niagara International Airport when it went down about 10:20 p.m. ET Thursday.





Preliminary information recovered from the flight's cockpit voice and data recorders indicated that the plane underwent "severe" pitching and rolling motions after the landing gear was lowered and wing flaps were set for the approach, Steve Chealander of the National Transportation Safety Board said Friday afternoon.





"The crew discussed significant ice buildup, ice on the windshield and leading edge of the wings," Chealander said.





"The crew attempted to raise the gear and [reset] flaps shortly before the recordings ended," he said. iReport.com: Are you there? Let us know





The plane crashed into a home in Buffalo, killing all 49 people aboard and one person on the ground. Firefighters brought under control a blaze at the crash site on Friday, blaming a natural gas leak for the fire's persistence.





Two occupants of the house survived -- a woman and her daughter -- and were released from a hospital after treatment for minor injuries, authorities said. Read about the escape





The first sign the air traffic controllers had of trouble was when Flight 3407 went off the radar.





Before that, it had been business as usual. The first officer, who was the co-pilot, had no sign of stress in her voice as she talked with air traffic control. The plane was cleared for approach.





About a minute later, the air traffic controller said that contact with the plane had been lost and asked whether crews in other aircraft could see anything. No one responded. The controller then said there might be a plane down.





Although there was a mix of sleet and snow in the area, other planes landed safely at the airport about the time the flight went down.  Watch what weather was like when disaster happened »





The crew of a Delta flight reported rime icing, a condition in which ice quickly builds up on the leading edge of the wings. A US Air flight also reported icing.





CNN meteorologist Chad Myers noted that there was "icing all over western New York" at the altitude the plane was flying.  See how ice affects airplanes »





"Almost every minute of their flight was in an ice event," he said.





The NTSB's Chealander said the flight crew reported that visibility was about 3 miles and there was snow and mist as they descended.





The voice and data recorders indicated that the plane's internal de-icing was on during the landing approach, he said.  Watch report from witness: "All I saw was flames" »





"A significant ice buildup is an aerodynamic impediment," Chealander said.





Tony Tatro was on his way home from the gym when the plane flew about 75 feet above him. The craft's nose was lower than usual, and and the left wing was tilted, he said.





"The engines didn't sound typical, didn't sound normal," he said.  Watch witness describe how plane went down »





The plane was loud as it came in, as if for a takeoff rather than for a landing, said David Luce, who lives 300 feet from the crash site.





"The engines sounded like they were revving at very high speed, an unnatural sound," Luce said. "Then the engine cut out -- stopped. And within a couple of seconds, there was this tremendous explosion.





"It was an enormous explosion. It sounded like it hit, frankly, right in our backyard. ... The house shook; the windows shook; the ground shook," he said. "It was a real blast."  Watch Mary Jane
how many died abroad what did ntsb say Officials say all 49 aboard the plane did what? what were the number of casualties Crew attempted to raise gear and reset flaps before what? what did the crew attempt to do Tapes indicate crew discussed ice buildup on what?
49 people Preliminary information recovered from the flight's cockpit voice and data recorders indicated that the plane underwent "severe" pitching and rolling motions after the landing gear was lowered and wing flaps were set for the approach, killing 50. the recordings ended," raise the gear and [reset] flaps the plane's wings and windshields
question: how many died abroad, answer: 49 people | question: what did ntsb say, answer: Preliminary information recovered from the flight's cockpit voice and data recorders indicated that the plane underwent "severe" pitching and rolling motions after the landing gear was lowered and wing flaps were set for the approach, | question: Officials say all 49 aboard the plane did what?, answer: killing | question: what were the number of casualties, answer: 50. | question: Crew attempted to raise gear and reset flaps before what?, answer: the recordings ended," | question: what did the crew attempt to do, answer: raise the gear and [reset] flaps | question: Tapes indicate crew discussed ice buildup on what?, answer: the plane's wings and windshields