GLENVILLE, N.Y. (AP) -- Investigators say there was no mechanical failure or malfunction in a small plane that crashed in an upstate New York river, killing two men and a boy.

Witnesses told the National Transportation Security Board that the pilot barely got off the ground before stalling and falling tail-down in the Mohawk River near the Schenectady County Airport on June 14.

The NTSB found the Piper Cherokee Arrow's flaps were retracted rather than partially extended for a short-field takeoff and the landing gear was extended.

Krishnan Raghavan, Mathai Kolath George and George's 11-year-old son, George Kolath, all drowned. The NTSB's preliminary report says Raghavan was a certified flight instructor and George was his first student. It's still not known who was at the controls.

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