Superspeedy Underwater Weapon

Superspeedy Underwater Weapon: BLOG: SciAm Observations: "You may have seen recent news reports about Iranian tests of a new high-velocity underwater missile. The New York Times (April 2) said that the new subsurface weapon is among the world's fastest and can outpace an enemy warship. Gen. Ali Fadavi of Iran's elite Revolutionary Guards stated that 'even if an enemy's warship sonar can detect the missile, no warship can escape from this missile because of its high speed.' Fadivi added that it took six years to build and that 'only Russia had a missile that moved underwater as fast as the Iranian one, which he said had a speed of about 225 miles per hour.'
This story may ring familiar to long-term SciAm readers, who may recall an article the magazine published some five years ago on supercavitating weapons--unusual devices that can travel underwater at surprisingly high speeds because they are surrounded by large, friction-cutting air bubbles. ['Warp Drive Underwater'; Scientific American Magazine; May 2001; by Steven Ashley, pages 70 to 79].
The scenes from the Iranian state television video broadcast of tests (available here) almost undoubtedly depict a supercavitating torpedo, likely similar to the Russian 'Shkval' underwater rocket described in the article. "