Koen -- whose boat has been used for rescues that included "Miracle on the Hudson" Flight 1549 -- was out on the water with members of New Square Hatzalah and Monsey Chavirim to search for the body of a Rockland County man who had jumped last week.
Sonar showed something near a buoy, but it was nothing, said Koen, who is a second assistant fire chief in Rutherford.
Two divers had resurfaced there when one saw the 25-year-old Somerset County woman plunge more than 200 feet. Moments later, a New York Police Department chopper arrived.
"They saw the divers getting back into the boat and thought we were a rescue team," Koen said. "Then we saw the helicopter hovering over one spot. I cut the anchor lines and went over.
"I found her floating on her back."
Koen pulled alongside and tried to throw her a line.
"I can't get up," she said. "My legs are broken."
Climbing down the diver ladder, Koen got a line under her arms. The divers and EMS workers then pulled her on deck, and Koen steered the "Lt. Michael T. Murphy" to the Manhattan shore.
"I just nosed up and police and EMS came aboard," he said. "They packaged her up and Marine One transferred her to land."
She was recovering at St. Luke's-Roosevelt Hospital, Port Authority officials said.
"These kinds of things -- it's all very serendipitous," he told Daily Voice. "Not that many people keep an operational boat during the winter, so I get a lot of work.
"Things just seem to happen around me."
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