Throughout history, nations have used demonstrations of their military capabilities and prowess to garner the respect of allies and opponents alike. Even in today’s world of political statements and nuanced diplomacy, few things can impress on the world stage quite like a show of military strength, and even within that scope, even fewer are as daunting and formidable a demonstration of a nation’s might than deploying a new nuclear asset.

Unfortunately for India, however, those same opportunities to impress the world can also be incredibly embarrassing.

Last year, India had just fielded the nation’s first ever nuclear ballistic missile submarine, an important part of any nation’s nuclear deterrent strategy. By maintaining a nuclear missile submarine somewhere around the globe, it eliminates an opponent’s ability to destroy your nuclear response capabilities. Nuclear submarines account for a third of America’s nuclear triad, and when operational, India’s nuclear submarine promised to do the same. A nuclear capable ballistic missile submarine ensures India could launch a 2nd strike response if ever attacked… provided the submarine remains functional.

“Arihant is the most important platform within India’s nuclear triad covering land-air-sea modes,” the Hindu, an Indian national news outlet, reported.

But then something went wrong. An issue referred to as “human error” left India’s nuclear sub, the Arihant, in need of significant repairs just as it was about to enter into service. That human error, it turns out, was a rather embarrassing one… someone left the hatch open while the sub was docked, allowing water to flood the submarine’s propulsion compartment and causing serious damage to the vessel. Just like that, the nearly $3 billion submarine was suddenly out of commission for nearly a year. According to Indian officials, the submarine saw nearly six months of service prior to the accident, but there is currently little evidence to corroborate that claim.

The laundry list of repairs the submarine required following the incident included having pressurized water coolant pipes cut out of the submarine and replaced, likely because being exposed to sea water could lead to corrosion and eventually a failure in the lines. Those pipes funnel coolant and water into the submarine’s 83 megawatt nuclear reactor, meaning a leak in one could result in a total meltdown of the submarine’s power plant.

The Arihant is a modified version of the Russian Akula-class attack submarines, with changes made to accommodate a variety of ballistic missiles, including India’s K-15 short-range and K-4 intermediate-range nuclear platforms, long seen as a deterrent against aggression from India’s diplomatic and occasional military opponent, Pakistan.