On to the Next Block
Designers look forward as Navy funds next Virginia-class sub version
By RICHARD R. BURGESS, Managing Editor
Design for Affordability
have built four Block I submarines
and built or are building six Block
II versions.
The contract immediately provides $2.4 billion to fund construction this fiscal year of the first
Block III submarine, North Dakota.
A key cost-saving feature of the
Block III is a redesigned bow section that replaces the spherical
sonar with large aperture sonar
and the 12 single-cell Tomahawk
cruise missile vertical-launch tubes
with two large-diameter tubes
capable of carrying the Multiple All-up-round Canister
(MAC), which houses cells for Tomahawks.
“We’ve done everything we can with this tube to
make it common with the [Ohio-class guided-missile
submarine] SSGN tube,” said Kurt A. Hesch, director
of design and engineering for the Virginia-class submarine program at Electric Boat. “Its interface with payloads is the same. We have a very credible way for us
to bounce back and forth with the SSGN and the use of
payloads.”
Each MAC features seven cells — six for Tomahawks and one for service access, hence no loss of missile capacity.
Electric Boat avoided the temptation to increase capacity — and cost — with the redesigned bow to use all 14
cells for missiles. The Navy required only 12 missile cells.
“We potentially could have seven Tomahawks [in
each MAC], so we made a conscious decision working
with the Navy to minimize the cost and maximize the
affordability,” Holmander said.
Electric Boat is acquiring a spare MAC from the
SSGN program to demonstrate on its prototype large-diameter tube later this year.
Holmander said the redesigned bow “would save
$40 million per ship, an $800 million program savings” over the 20 Virginia SSNs in Blocks III, IV and V.
Designers are looking at new capabilities for the fourth block of
Virginia-class submarines.
■ Block III improvements will be leveraged for expanded capabilities.
■ Design opportunities include payload options, a redesigned sail
and electric actuation.
■ Life-cycle cost savings are essential to fund an increased production rate.
The ink is hardly dry on the Navy’s multiyear contract for Block III of the Virginia-class nuclear-powered attack submarine and designers are
busy preparing for the next version, Block IV, which will
include new features and cost-saving measures.
“Even though we just got a contract and there’s been
a lot accomplished, there’s such urgency on my behalf to
get something going as quickly as possible on what we’re
calling a DFA II — Design-for-Affordability II — in support of the Block IV,” said John D. Holmander, General
Dynamics’ Electric Boat vice president and Virginia-class
submarine program manager.
The Navy expects to release a request for proposals for
Block IV no later than January 2013, according to a
spokesman for Naval Sea Systems Command (NAVSEA).
An earlier effort, DFA I, was instrumental in achieving the cost savings necessary to allow the Navy to
reach a goal of building a Virginia SSN for less than $2
billion (in fiscal 2005 dollars). That threshold was necessary to allow the Navy to increase production from
one to two SSNs per year during Block III production.
On Dec. 22, the Navy awarded the $14 billion contract for eight Block III Virginia SSNs to Electric Boat
and Northrop Grumman Shipbuilding, which build the
submarines under a teaming arrangement. Production
will increase to two per year in 2011. The two shipyards
