Beyond Design Basis
The Marine Version
Current Events
Fukushima and North Anna are technical
historical markers of unique circumstances of
seemingly low probability events that can hold
significant consequences with respect to nuclear
power plants.
The circumstances involved showed an inherent
resiliency built into the structures of the
buildings and components.
Current Events
Recent at-sea accidents involving US Navy
submarines are worth looking at in the same
light as the nuclear power plants.
The power plant and submarine are very similar.
Both represent superior technology in systems,
structures and components and perform very
reliably for many years.
Emergency Blow
Incident One
• On 8 January 2005 at 02:43 GMT, San
Francisco collided with an undersea mountain
about 675 kilometers (364 nautical miles, 420
statute miles) southeast of Guam while
operating at Hi speed and more than 200 feet
(61 m) deep. The collision was so serious that
the vessel was almost lost — accounts detail a
desperate struggle for positive buoyancy to
surface after the forward ballast tanks were
ruptured.
USS San Francisco-SSN 711
USS San Francisco-SSN 711
USS San Francisco-SSN 711
Aftermath
• 23 crewmen suffered injuries
• One fatality. Petty officer died of head injuries on
January 9th due to abrupt contact with ship’s internal
structure.
• Crew performed well to save ship.
• Cause determined to be improper navigation and
failure to consult ship’s instrumentation.
• Ship inspected. Foundations. Rx Plant, Engine Room,
Hull circularity
• San Francisco repaired with a bow from a
decommissioned ship (Honolulu). Completed in 2008.
Incident Two
• On 20 March 2009 Hartford collided with
amphibious transport dock USS New Orleans
(LPD-18) in the Strait of Hormuz, slightly injuring
15 sailors on board.
• New Orleans (new ship) suffered ruptured fuel oil
tank. Lost 25,000 gallons of oil.
• Sub rolled 90 degrees port and starboard after
collision.
• Both ships continued under own power. Sub
crew responsible for collision.
USS New Orleans
USS Hartford-SSN 768
USS Hartford-SSN 768
USS Hartford in Open Sea
In Thames River to Sub Base Groton
Consequences
• Hartford repaired by Electric Boat.
• Hull circularity determined to be satisfactory.
• New sail fabricated. Had to be redesigned as
original plans not compatible with modern
construction methods.
• Retirees called back to help.
• Final cost about $120 Million. Sub returned to
service in February 2011.
Happy Ending
• Hartford recently completed a 6 month patrol
and accomplished tasking not attempted in
over 15 years according to the COB (chief of
the boat). Ship performed as expected which
considering what it is designed to do is rather
impressive.
Summary
• Fukushima survived the earthquake and
tsunami after almost 40 years of service.
Earthquake was about 10 times greater than
design basis.
• North Anna survived an earthquake stronger
than it’s design basis and has returned to
service.
• Both submarines survived to be repaired and
return to service.
Summary-cont’d
• Platforms that push the envelope exact a cost
both monetarily and on operators. Nuclear ships
and power plants are hard on their people. No
industry is more introspective save NASA.
• These incidents serve to prove that the design,
material specifications, building techniques,
operational protocols, and maintenance of these
unique structures have been accomplished well.
Our collective efforts are clearly worthy.
• These results allow evolution with confidence!