Are US Navy's super carriers a relic of wars past?

Budget pressures at the Pentagon have renewed a debate about the value of the United States Navy's giant aircraft carriers, with critics arguing the warships are fast becoming costly relics in a new era of warfare.

With the Pentagon facing US$500 billion in cuts over the next decade, a navy officer has dared to question the most treasured vessels in his service's fleet, saying the carriers are increasingly vulnerable to new weapons and too costly to operate.

"After 100 years, the carrier is rapidly approaching the end of its useful strategic life," wrote Captain Henry Hendrix in a report published this month by the Centre for a New American Security, a Washington think tank with close ties to President Barack Obama's administration.

Changes in naval warfare mean that carriers "may not be able to move close enough to targets to operate effectively or survive in an era of satellite imagery and long-range precision strike missiles", Hendrix wrote.

Under US law, the military is required to maintain 11 aircraft carriers. Ten are currently in service after the retirement of the USS Enterprise, which is due to be replaced in 2017 with the USS Gerald Ford, the first of a new class of "big decks".

The new carrier carries a prohibitive price tag of US$13.6 billion, double the cost of the last aircraft carrier. And that does not count the US$4.7 billion spent on research and development for the new class of carriers.