Both the Dictionary of American Naval Fighting Ships (at http://www.history.navy.mil/danfs/o3/ono.htm) and NavSource Online (at http://www.navsource.org/archives/12/170128.htm) give the boat's speed in "miles per hour", implying statute miles per hour. This is unusual for a boat or ship, and may be a mistaken reference to 15 knots. However, if the boat's speed really is given correctly in statute miles per hour, the equivalent in knots would be 13.
navy.mil
history.navy.mil
Both the Dictionary of American Naval Fighting Ships (at http://www.history.navy.mil/danfs/o3/ono.htm) and NavSource Online (at http://www.navsource.org/archives/12/170128.htm) give the boat's speed in "miles per hour", implying statute miles per hour. This is unusual for a boat or ship, and may be a mistaken reference to 15 knots. However, if the boat's speed really is given correctly in statute miles per hour, the equivalent in knots would be 13.
