"The USS Taurus was part of the US Navy's PHM program (Patrol Combatant-Missile Hydrofoil) which was intended to be the most mobile Navy unit in history. These boats were heavily armed, carrying a 76 mm gun mount and eight harpoon missiles, and they were incredibly fast and agile, topping out at 51 knots (58.7 mph). They were powered by a gas turbine engine similar to the one used on the DC-10 jumbo jet. They were most succesful intercepting smuggled shipments of drugs, because of their speed. The drug smugglers would call them, "the grey terror that flies," and even a rumor that the PHM craft were present was enough to keep the smugglers away."

http://www.aae.uiuc.edu/cetan/