A 43-year-man and 39-year-old woman were both wearing life vests when their plane plunged into the water.
The crash happened around 5:30 p.m. Sunday. The Piper PA-32 had departed from Trenton-Robbinsville Airport in Robbinsville, New Jersey.
On the 911 recording, the passenger is heard shouting into his cellphone: "The plane is filling up!" The dispatcher tells him they have to get out to avoid being trapped.
The man then calls to the pilot, "Get out! Get out! ... We're going down!" Once he escapes, he yells, "The water's freezing!"
Authorities have identified the pilot as 39-year-old Denise De Priester, of East Windsor, N.J., and the passenger as 43-year-old Christopher Smidt, of Colonia, N.J.
Eyewitnesses saw the aircraft go down and become submerged in the river. The two victims were in the water for about 20 minutes before they were pulled to safety by an off-duty Yonkers police detective and his 12-year-old son, who used a boat from the Hudson River Pilot House to save the couple.
"They were drifting pretty quick," rescuer Danny Higgins said. "And if we didn't get out there quick enough, well, let's just say we're glad to get there quick."
"The lady was mumbling some stuff, I don't know what she was mumbling about," Danny Higgins, Jr., said. "They were both very stiff. They were numb, very cold."
De Priester and Smidt were listed in stable condition at Jacobi Medical Center in the Bronx on Monday. The plane was flying under visual flight rules, so the pilot was not receiving air traffic control services.
The National Transportation Safety Board is investigating the cause of the crash.
In 2009, Capt. Chesley "Sully" Sullenberger safely landed US Airways Flight 1549 on the Hudson River in New York after striking a flock of geese. All 155 people aboard survived.
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