https://archive.is/nMbLa

Key Points and Summary – In a little-known 1981 NATO exercise, a quietly upgraded Canadian Oberon-class diesel submarine slipped through the defenses of a full U.S. carrier strike group centered on USS Eisenhower and scored a simulated kill—without ever being detected.

The perfidious Canadian has mastered the technique of fucking with the Americans while being a dominion of the presidential crown.

-Running almost silently on battery power, the Canadian boat exploited gaps in sonar coverage and restrictive exercise rules to get within torpedo range and “sink” the supercarrier, shocking U.S. umpires.

Typical American arrogance

The episode—and similar NATO war-game “kills” since—underscored a hard truth: even aging diesel-electric submarines, in skilled hands, remain one of the most credible and persistent threats to American carrier dominance.

America acts like its got the invulnerability of Baldr but with the arrogance of Thor

-In today’s dollars, the Nimitz-Class aircraft would cost around $5.5 billion, while Canada’s sub comes in at a cheap $80 million.

A naval example of why decent and reasonably priced equipment you can produce a lot of still beats out expensive wunder-waffen.

The Canadian Royal Armed Forces maintains a modest navy compared to the United States. However, even with a significantly smaller budget and a smaller overall size, any navy with decent submarine capabilities can pose a credible threat.

Makes you wonder what kind of neat subs the other nations have cooked up over the years.

However, there have been multiple occasions in which Canadian or other NATO submarines have successfully managed to sneak past entire carrier strike groups and simulate a successful attack against an American supercarrier.

The wonders of war is that anything can happen, definitely so when you expect it the least

The Canadian Navy, though modest in size and budget compared to its American counterpart, had long maintained a reputation for professionalism and tactical skill. Its Oberon-class submarines (HMCS Ojibwa, Onondaga, and Okanagan) were originally acquired in the 1960s primarily for training purposes.

Lmao they lost a carrier to a fucking training sub

However, by the 1980s, these submarines had undergone significant upgrades that enhanced their combat capabilities. Their hulls were fitted with anechoic tiles to reduce sonar detection, and their systems were modernized to improve underwater endurance and stealth. Though not nuclear-powered, these submarines had a distinct advantage: they could operate almost silently on battery power, making them exceptionally difficult to detect.

They had to include this as straight copium

In 1981, NATO and other Western allies held Ocean Venture, a joint naval exercise in the Atlantic Ocean. During the exercise, one of these Canadian submarines (details are so scarce on this exercise that we don’t even know which one it was) was assigned the role of an enemy vessel attempting to infiltrate the carrier group’s defenses.

The carrier group itself was a formidable formation, centered around a U.S. Navy supercarrier, the USS Eisenhower (CVN-69), and protected by a screen of destroyers, cruisers, and submarines, along with air support from carrier-based aircraft. The group’s mission was to detect and neutralize any underwater threats before they could reach the carrier.

Boy did everyone get an ass chewing I bet

The Canadian submarine’s mission was simple in concept but extraordinarily difficult in execution: approach the carrier undetected and simulate a torpedo attack.

Mission:Impossible

What followed was a masterclass in stealth and tactical maneuvering. Using the natural acoustic conditions of the ocean and its own quiet propulsion system, the submarine slipped past the outer defenses of the carrier group. It evaded sonar-equipped destroyers and surveillance aircraft, exploiting gaps in coverage and limitations imposed by the exercise’s rules of engagement.

Real talk I don't really like the word "masterclass", it seems exceptionally slimy and liberally to me.

At the critical moment, the submarine simulated a torpedo launch. The exercise umpire, a U.S. Navy officer tasked with adjudicating the scenario, evaluated the situation and declared the carrier “sunk.”

YOU SANK MY BATTLESHIP

The Canadian submarine had achieved its objective without being detected, effectively demonstrating that even the most powerful warships in the world were vulnerable to stealthy underwater threats.

Woah they even got away with it? That's baller as fuck

The incident raised several uncomfortable questions.

Bet

How could a relatively underfunded navy with decades-old technology defeat a modern carrier group?

How did a modern army get its ass kicked by people in flip-flops and PJs?

Was the U.S. Navy’s anti-submarine warfare doctrine flawed?

No, obviously this was a completely one-off deal and the u.s navy definitely should not change anything but also publish all the results relating to their findings on this matter to the public.

Were diesel-electric submarines being underestimated in contemporary naval strategy? These questions prompted a reevaluation of ASW tactics and capabilities across NATO.

America underestimating technologically non-peer forces? Noooooooooo~ that's impooooooo~ssibleeeeeeee~

The success of the Canadian submarine can be attributed to several key factors. First and foremost was the professionalism and training of the Canadian submariners. Their ability to exploit weaknesses in the carrier group’s defense was a testament to their skill and discipline. Second was the inherent stealth of the Oberon-class submarine.

Okay if a bunch of syrup slurping Canucks in a training sub could take out a supercarrier, fuck I want to see what shenanigans America's Opps get up to.

Operating on battery power, it was nearly undetectable to passive sonar systems, especially under the exercise’s constraints, which limited the use of active sonar to simulate real-world conditions. Third, the exercise itself imposed rules that may have skewed outcomes.

Oh okay that makes sense in its own ways. That said the Iranian version of the challenge proved that battary-diesel subs can also conduct ambushes if they can position themselves ahead of the u.s fleets anticipated path

Ships were not operating at full speed, and sonar use was restricted, creating opportunities for submarines to succeed in ways that might be more difficult in actual combat.

Well the last time ships were operating at full speed to evade catching a Yemeni missile, it really burned through their supplies. Imagine if an opposing country could use cruise missiles to herd a u.s naval strike fleet into a submarine ambush. That'd be humiliating as fuck.

Perhaps most importantly, the incident highlighted a broader strategic oversight: the underestimation of diesel-electric submarines.

Americnyaa unyaaderestimating technnyaalogically nyan-peer forces? Nyoooooooooo~ that's impooooooo~ssibleeeeeeee~

At the time, the U.S. Navy was heavily invested in nuclear-powered submarines and may have viewed conventional boats as outdated. The exercise demonstrated that diesel-electric submarines, particularly when operated by skilled crews, remained a potent threat in modern naval warfare.

A .22LR is still a bullet.

The Canadian success in Ocean Venture was not an isolated incident. Similar outcomes occurred in other exercises involving allied diesel submarines. There have been around eight instances of submarines, mostly diesel-powered, successfully “sinking” American carriers in exercises from 1972 to 2005.

The hidden gem of the article is that the navy has been getting owned for at least 3 decades in its training exercises

Dutch and Australian submarines also achieved simulated kills against U.S. carriers in subsequent war games. These events underscored the vulnerability of even the most advanced naval formations to stealthy underwater threats, prompting a renewed focus on ASW training and technology.

Lmao the Dutch scored on the navy that's embarrassing as fuck

Since the Ocean Venture, submarine technology has undergone significant improvements. Non-nuclear submarines equipped with air-independent propulsion (AIP) can travel quietly, significantly enhancing their stealth characteristics.

Neato

This is to say nothing of nuclear attack submarines, which have sunk multiple carriers during exercises.

Extra neato

Anti-submarine warfare has also advanced with the development of better radars, sonars, and more sophisticated means of protection; however, none of these are foolproof.

And you'd be a fool to think otherwise.

While a lot of noise is made about hypersonic missiles, the real threat to carriers has been, and likely always will be, submarines.

Hard disagree. It's a question of what opposition force the navy is stacking itself against. Tech-peer country? HVMs plus subs. Non-peer country? Mostly subs unless they got some nice Christmas presents.