NEWARK, N.J. — Investigators have concluded pilot error caused a small plane crash in New Jersey that killed a doctor and two other people last year.

The single-engine plane crashed in July 2010 in Fairfield after aborting a landing at Essex County Airport. Manhattan rheumatologist Margaret Smith as well as Michael Ferguson and wife, Theresa, died in the crash.

The 70-year-old Smith was piloting the plane that had departed from an airport in upstate New York.

Witnesses described seeing the plane touch down and then climb steeply before appearing to stall and plummet straight down.

An investigation by the National Transportation Safety Board released last week concluded Smith failed to maintain control during the aborted landing and had the plane’s flaps set improperly for that maneuver.