The Southwest Airlines plane that crashed at New York's LaGuardia Airport on Monday landed on its front nose wheel before its main landing gear touched down on the runway, U.S. safety investigators said on Thursday, according to a Reuters report.
A witness described the Boeing 737's landing gear as looking "out of shape" as it approached the runway.
Investigators said the the plane's nose was pitched slightly upward, at an angle of 2 degrees mere seconds before landing, but landed while pitched three degrees downward.
Planes typically touchdown on their main landing gear before landing on their front landing gear.
The plane slid for 19 seconds, travelling roughly halfway down the runway before coming to a rest in a grassy area off the side.
Nine passengers were injured, and reported injuries to their necks and backs.
A Southwest spokeswoman said the landing was "not in accordance with our operating procedures".