by Kris Osborn
And technical adjustments to the sub-launched Trident II D5 nuclear weapon such that it can serve for decades well beyond its current service life extending to 2040.
The Navy has already been working on technical upgrades to the existing Trident II D5 in order to prevent obsolescence and ensure the missile system remains viable for the next several decades.
The US Navy is accelerating upgrades to the nuclear warhead for its arsenal of Trident II D5 nuclear-armed submarine launched missiles — massively destructive weapons designed to keep international peace by ensuring and undersea-fired second-strike ability in the event of a catastrophic nuclear first strike on the US.
Navy Vice Adm. Terry Benedict, director of Navy Strategic Systems Programs, told lawmakers about a long-term sustainment of the triad’s sea-based leg.
“While our current life-extension efforts will sustain the D-5 [Trident submarine-launched ballistic missile] system until the 2040s, the Navy is already beginning to evaluate options to maintain a credible and effective strategic weapon system to the end of the Columbia class service life in the 2080s,” Benedict said.
The Navy has modified an existing deal with Charles Stark Draper Laboratory has to continue work on the missile’s MK 6 guidance system, an agreement to continue specific work on the weapon’s electronic modules. The modification awards $59 million to the firm, a DoD statement said.
As part of the technical improvements to the missile, the Navy is upgrading what’s called the Mk-4 re-entry body, the part of the missile that houses a thermonuclear warhead. The life extension for the Mk-4 re-entry body includes efforts to replace components including the firing circuit, Navy officials explained.
Navy and industry engineers have been modernizing the guidance system by replacing two key components due to obsolescence – the inertial measurement unit and the electronics assembly, developers said.
The Navy is also working with the Air Force on refurbishing the Mk-5 re-entry body which will be ready by 2019, senior Navy officials said.
Navy officials said the Mk-5 re-entry body has more yield than a Mk-4 re-entry body, adding that more detail on the differences was not publicly available.
The missile also has a larger structure called a release assembly which houses and releases the re-entry bodies, Navy officials said. There is an ongoing effort to engineer a new release assembly that will work with either the Mk-4 or Mk-5 re-entry body.
The Trident II D5, first fired in the 1990s, is an upgraded version of the 1970s-era Trident I nuclear weapon; the Trident II D5s were initially engineered to serve until 2027, however an ongoing series of upgrades are now working to extend its service life.
The Navy is modernizing its arsenal of Trident II D5 nuclear missiles in order to ensure their service life can extend for 25 more years aboard the Navy’s nuclear ballistic missile submarine fleet, service leaders said.
The 44-foot long submarine-launched missiles have been serving on Ohio-class submarines for 25 years,service leaders explained.
The missiles are also being planned as the baseline weapon for the Ohio Replacement Program ballistic missile submarine, a platform slated to serve well into the 2080s, so the Navy wants to extend the service life of the Trident II D5 missiles to ensure mission success in future decades.
Under the U.S.-Russia New START treaty signed in 2010, roughly 70-percent of the U.S.’ nuclear warheads will be deployed on submarines.
Within the last several years, the Navy has acquired an additional 108 Trident II D 5 missiles in order to strengthen the inventory for testing and further technological development.
Trident II D5 Test
Firing from the Atlantic Ocean off the coast of Florida last year, a specially configured non-armed “test” version of the missile was fired from the Navy’s USS Maryland. This was the 161st successful Trident II launch since design completion in 1989, industry officials said.
The missile was converted into a test configuration using a test missile kit produced by Lockheed Martin that contains range safety devices, tracking systems and flight telemetry instrumentation, a Lockheed statement said.
The Trident II D5 missile is deployed aboard U.S. Navy Ohio-class submarines and Royal Navy Vanguard-class to deter nuclear aggression. The three-stage ballistic missile can travel a nominal range of 4,000 nautical miles and carry multiple independently targeted reentry bodies.
The U.S. and UK are collaboratively working on a common missile compartment for their next generation SSBNs, or ballistic missile submarines.
The 130,000-pound Trident II D5 missile can travel 20,000-feet per second, according to Navy figures. The missiles cost $30 million each.
The “Bulletin of the Atomic Scientists” futher describes the weapon — “The Trident D5s carry three types of warheads: the 100-kiloton W76/Mk-4, the 100-kiloton W76-1/Mk-4A, and the 455-kiloton W88/Mk-5 warhead, the highest-yield ballistic missile warhead in the U.S. arsenal.”
