Russia is sending China the second of eight new Kilo class submarines this month. All eight boats are expected to be in service by next year. This is somewhat faster than expected. The Kilo is the best diesel-electric submarine the Russians have ever produced. Developed at the end of the Cold War (the 1980s), the design has undergone improvements since then. The Kilo is a 2,300 ton (surface displacement) boat with six torpedo tubes and a crew of 57. It is  very quiet, and can travel about 700 kilometers under water at a quiet speed of about five kilometers an hour. Kilos carry 18 torpedoes or SS-N-27 anti-ship missiles (with a range of 300 kilometers and launched underwater from the torpedo tubes.) The combination of quietness and cruise missiles makes Kilo very dangerous to American carriers. The SS-N-27 has a half ton warhead, which wont sink a carrier, but could easily shut down aircraft operations for a while.