The small Mooney plane went down in the woods at about 5:20 p.m., about a half mile northeast of the airport. It's not clear whether the pilot and passenger were seriously injured, but they were airlifted to Stony Brook Hospital. Their names were not released.
Sag Harbor resident Bill Kirrane and his wife were among about 30 people standing outside the airport to protest the noisy air traffic, and he said he saw the plane flying low over a fence that separates the woods from the airport before it went down. A few minutes later he saw smoke.
"They took a pretty hard hit, I know that. There was a lot of noise when it hit," he said.
Kirrane said a good Samaritan who had been driving nearby got through the fence and appeared to pull both people - and man and a woman - out of the aircraft. Emergency crews arrived moments later.
"He was covered in blood, and at first we thought it was his, but it was the passengers'," Kirrane said. "That guy was a real hero."
Kirrane said he didn't recognize either of the passengers and was not sure how seriously they were injured.
Federal Aviation Administration spokeswoman Arlene Salac said the agency is investigating, along with the National Transportation Safety Board.
The small airport is located about 100 miles east of New York City, in an area frequented by celebrities and the wealthy. According to the airport's website, it serves a mix of private pilots, charter flights and commercial businesses. About 16,000 aircraft use the airport it annually, mostly between the months of May to October.
The airport was temporarily closed during the investigation, halting normally busy Sunday traffic off the island.
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