HMS Eagle was a British 64-gun third-rate ship of the line of the Royal Navy, launched on 2 May 1774 at Rotherhithe.

[1] On 7 September 1776, the experimental American submarine Turtle, under the guidance of army volunteer Sergeant Ezra Lee, was alleged to have attacked HMS Eagle, which was moored off what is today called Liberty Island, but was unable to bore through the hull.

British naval historian Richard Compton-Hall stated that the problems of achieving neutral buoyancy would have rendered the vertical propeller useless.

The route Turtle would have had to take to attack HMS Eagle was slightly across the tidal stream which would, in all probability, have resulted in Ezra Lee becoming exhausted having only 20 minutes of air.

[2] In the face of these and other problems Compton-Hall suggests that the Turtle got nowhere near HMS Eagle and the entire story was fabricated as disinformation and morale-boosting propaganda, and that if Ezra Lee did carry out an attack it was in a covered rowing boat rather than Turtle.