The National Transportation Safety Board is investigating two separate Orange County plane crashes, including one that killed a New Jersey pilot.State police say 79-year-old Frank Holland, of West Orange, New Jersey, was the lone occupant of a twin-engine Cessna 310 that crashed into a marsh in Montgomery. Airport officials say Holland?s plane took off about 1 p.m., but failed to gain significant altitude. It crashed and burned moments later near the runway. Police say Holland drove to the airport to check on the plane, which was being serviced. Holland?s son, who officials say was at the airport with his father, called police after noticing his father was having trouble taking off. The National Transportation Safety Board investigation could take more than a year for an official determination on what caused the plane to go down.According to police, a separate Orange County plane crash Thursday resulted in a 71-year-old pilot being taken to the hospital with head injuries. Investigators say the pilot, whose name hasn?t been released, took off from Randall Airport in Middletown, overshot the runway and crashed. The pilot is recovering at Arden Hill Hospital. That crash is also under investigation.