U.S. Navy nuclear submarines can travel around the world under water, generating a supply of breathing oxygen as required. Virginia-Class subs generate oxygen utilizing what is called the Integrated Low Pressure Electrolyzer (ILPE), an electrolytic system made by Hamilton Sundstrand (a unit of United Technologies Corp. (UTX)).The heart of the ILPE involves proton exchange membrane (PEM) electrolyzer technology (right), which uses electricity and distilled water as inputs to create high purity breathing oxygen (and byproduct hydrogen). In 2009, Proton Energy Systems announced it would provide electrolyzer stacks to Hamilton Sundstrand for the ILPE.
When the electrolyzers have been integrated into complete ILPE systems, they look like an arrangement of individual tan cabinets that have been bolted together (left). This is because the sections must be transported in pieces through the narrow passageways on a sub, until the ILPE undergoes final assembly in place.
On March 19, 2011, the USS New Hampshire (below), a Virginia-class attack boat that entered service in 2008, was on ICEX 2011 arctic maneuvers. While approaching the Applied Physics Laboratory Ice Station, a floating ice station north of Prudhoe Bay, Alaska, its ILPE oxygen generator failed. According to NAVSEA, the sub switched to its backup oxygen system — using sodium chlorate “candles” — and continued normal operations.
According to a 3/21/2011 Reuters article:
"Daniel Coulom, a spokesman for Hamilton Sundstrand, confirmed late Monday that company staff would travel to the ship to help repair the oxygen generator, but said it was too early to speculate on what caused the problem."
A 3/28/2011 article in the NavyTimes states:
"The technicians arrived at Prudhoe Bay late March 24, according to Kevin Copeland, spokesman for Submarine Force Atlantic. They flew to the ICEX base March 25 and were to be taken by helicopter to the sub March 26."
No word on if any repairs were conducted, or even if the mode of failure has been discerned.