The Navy’s Nimitz-class aircraft carrier was ‘destroyed’ by an old French submarine

What you need to know: In a 2015 war game, the French Rubis-class submarine Saphir demonstrated surprising prowess by “sinking” the U.S. supercarrier USS Theodore Roosevelt, highlighting the vulnerabilities in the U.S. Navy’s anti-submarine defenses.

– Similar to Sweden’s Gotland’s success against the USS Ronald Reagan in 2005, the Saphir’s stealth and agility allowed it to evade the Carrier Strike Group’s defenses.

-While these incidents highlight the potential of relatively modest submarines, they also underscore the challenges supercarriers face, especially as smaller, low-cost threats such as drones and missiles continue to evolve. The lessons learned will be critical to U.S. strategy in the Indo-Pacific.

The Navy’s Humbling Lesson: French Submarine Defeats US Aircraft Carrier in 2015

The American aircraft carrier is the most expensive and advanced warship ever built. The modern supercarrier costs several billion dollars and can accommodate many thousands of sailors and does not have to be vulnerable to smaller, cheaper ships.

At least not in theory. But as a relatively modest French submarine proved in a war game in 2015, the American supercarrier is not invincible. Almost not.

A humiliating loss for the US Navy

The 2015 interaction between the French Rubis-class submarine, the Sapphireand the American Nimitz-class submarine, the USS Theodore Rooseveltwouldn’t have been a total surprise. The Sapphire managed to “sink” the ship. Roosevelt in the war game, which on paper is a surprise, yes.

But the incident took place just ten years after another similar incident involving the Swedes Gotland.

In 2005, the Gotland successfully ‘sunk’ the USS Ronald Reagan during a wargaming exercise. The Sapphire incident ten years later was quite similar; the Sapphire snuck past the Carrier Strike Group, which the Ronald Reaganand suffered a fatal blow.

The Sapphire incident, and the Gotland incident, served as a harbinger of the problems America’s aircraft carriers face today in the Middle East, where the relatively ungainly Houthis disrupt the operations of US airlines with the use of low-tech drones and missiles.

The French Navy is obviously not a mess. But the Sapphire is hardly a machine with the range or sophistication of a Nimitz-class aircraft carrier. So the reality that the Sapphire could cause significant damage to the Roosevelt was probably worrying and embarrassing.

To curb bad press and intelligence that would have emboldened adversaries like Russia and China, the U.S. Navy Sapphire incident, hoping to contain news of their poor anti-submarine capabilities.

Rubis-class submarine A smaller opponent

The Rubis class submarine isn’t exactly the adversary you’d expect to “sink” an American supercarrier. At the time of the Saphir-Roosevelt war game, the Sapphire was already a thirty year old ship, hardly a modern submarine. Smaller and lightly armed than most NATO submarines, the Rubis is not known for its destructive capabilities.

The Sapphire was built with modest dimensions.

The length is 73.6 meters, the width 7.6 meters and the draft 6.4 meters. By comparison, the US Ohio-class submarine is 170 meters long. The Sapphire displaces 2,400 tons and relies on a CAS-48 pressurized water nuclear reactor, an electric motor and an auxiliary single-shaft diesel generator. The propulsion system can generate a maximum speed of twenty-five knots. The Sapphire can operate at depths of up to 300 meters. And like other modern nuclear-powered submarines, the Sapphire can technically operate for twenty to twenty-five years at a time, although the submarine usually requires forty-five days of travel.

Hopefully the Sapphire incident allowed the US Navy to gain valuable insights into their anti-submarine warfare shortcomings. And hopefully those insights led to reforms. Because any future conflict in the Indo-Pacific will depend on the survivability of the aircraft carrier.

About the Author: Harrison Kass

Harrison Kass is a defense and national security writer with a total of more than 1,000 articles on issues relating to global affairs. Harrison, an attorney, pilot, guitarist and minor professional hockey player, joined the United States Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. Harrison listens to Dokken.

Image credits: Creative Commons and/or Shutterstock. The main image is of a Ford class aircraft carrier undergoing a shock test.