September 4,
2008: The U.S. Navy is getting its fifth
Virginia class SSN (nuclear attack sub) eight months ahead of schedule, and
under budget. The SSN New Hampshire cost $2.21 billion and took 72 months to
construct. The New Hampshire will be commissioned at the end of October.
Another new Virginia class SSN was commissioned this year, the first time in
twelve years that the navy put two nuclear subs of the same class into service
in one year. The navy expects to be doing that regularly in four years, as many
of the old Lost Angeles class SSNs reach the end of their useful lives and are
replaced by the Virginias.
The U.S. currently
has three classes of SSN. Most are the 6,900 ton Los Angeles-class SSNs.
Sixty-two of these submarines were built, and most are still in service. Armed
with four 21-inch (533-millimeter) torpedo tubes, they carry twenty-six weapons
for those tubes (either the Mk 48 torpedoes or BGM-109 Tomahawk cruise missiles). The last 31
Los Angeles-class SSNs added the Mk 45 vertical-launch system (VLS), which
carries another twelve Tomahawks. If built today, these late model Los Angeles
class boats would cost about $1.5 billion each.
The twenty-nine, 9,000 ton Seawolf-class SSNs
were supposed to replace the Los Angeles boats, but they proved too expensive. Only
three Seawolfs were built. The Seawolf was designed for the Cold War, carrying fifty
weapons for its eight 26-inch (660-millimeter) torpedo tubes. Seawolf was fast (top speed of over 60 kilometers an hour), and
much quieter than the Los Angeles boats. To replace the un-built Seawolfs,
the 7,800 ton Virginia-class was
designed. Think of it as a Los Angeles size hull with a lot of Seawolf
technology installed. The Virginia-class boats ended costing about half as much
as the Seawolfs. But that was largely possible because the Virginias used a lot
of the new technology developed for Seawolf.
