How a Single Swedish Submarine Defeated the US Navy

This episode of Real Engineering is brought
to you by Brilliant, a problem solving website that teaches you to think like an engineer. The US military has the strongest and most
diverse navy in the world. The US militaries fleet of aircraft carriers
is so large, it makes the US navy the second largest airforce in the world, second only
to the actual US Air Force. A single Nimitz- class aircraft carrier like
the USS Ronald Reagan, a 6.2 billion dollar nuclear powered ship, can carry the twice
aircraft as any other foreign carrier, which makes it even more shocking that it was sunk
by a single diesel powered swedish submarine during war games in 2005. A single submarine that cost the same as a
F-35 at 100 million dollars managed to sneak by an entire carrier task force, with anti-submarine
defences to enter the red-zone and score multiple torpedo hits on the USS Ronald Reagan, sinking
it virtually, before shrinking back into the vast ocean undetected. This was just one of many exercises where
the Swedish Gotland class submarine proved too stealthy for the world’s strongest navy. The new submarine proved so threatening that
the US military leased the Swedish sub for an additional year to develop strategies to
counter the silent threat. So what set the Gotland apart from other subs. Submarines’ primary instrument to detect
enemy subs is sonar. Sonar is essentially a finely tuned ear that
works like a whales or dolphins echolocation to create a 3D map of ocean around it. There is active sonar where the submarine
will send out a sound pulse called a “ping” and listen for the reflections, but in warfare
this isn’t a sound strategy, as that ping is detectable by enemies to give your exact
location, so passive sonar is used where no ping is emitted and instead you simply listen. These electronic ears are so accurate that
the nationality of submarines can be determined based on the operating frequency of the alternating
current used in it’s power systems. The 60 Hz alternating current of a US sub
could be differentiated from the 50 hz of European subs, if the transformers and other
electronics were not adequately insulated from the hull. The Swedes managed to create a submarine so
silent that it was practically undetectable by passive sonar, so how did they do this
at such a low cost? The Gotland was the first submarine in the
world to use a stirling engine as it’s power generator. Stirling engines are not a new concept with
the first being created and patented by Robert Stirling in 1816. Inspired by a series of high pressure steam
boiler explosions at the beginning of the industrial revolution, Stirling wanted to
create a safer engine that did not require such high pressures. I can’t be arsed trying to animate this
old drawing, let’s go for something simpler. He did this by creating a closed cylinder
containing a fixed mass of gas permanently sealed within. Here one side of the piston cylinder has a
large buffer space, which allows for a relatively constant pressure on this side of the piston,
while the other side fluctuates in pressure due to alternating heating cycles. When heat is applied to the outside of the
cylinder, the pressure increases causing the piston to move until the pressure equalizes. Now, if we cool the outside of the cylinder
with a heat exchanger, the pressure will drop and once again the piston will move. This is our basic pressure cycle to create
mechanical work. But, this is an insanely inefficient system,
as most of the energy we put into the system as heat is lost during the cooling cycle,
not to the gas, but to the actual cylinder wall, which provides no mechanical work. Robert Stirling solved this by adding a displacer
piston, which can drive the gas from one end of the cylinder to the other. Allowing this end to be permanently hot, and
the other permanently cold. So the cylinder wall is no longer experiencing
a temperature cycle. The pressure cycle here works slightly differently. First the air in the hot end expands and causes
the displacer to move into contact with the power piston, displacing more air from the
cold end to be heated and expanded, allowing work to be done on the power piston. The air on the hot end now has nowhere to
go, and so is driven to the cold end, where it is cooled and contracts causing work to
be done once again on power piston. This is our new pressure cycle. The efficiency of this system can be increased
further by placing what is essentially a heat battery in the tubes between the hot and cold
cylinder. This conserves a huge amount of heat that
would otherwise be wasted during the cooling cycle, and gives the heat back to the air
as it travels back to through. Robert Stirling dubbed this the regenerator. Now we have the foundations of a useful engine. By incorporating a coolant system and a heating
chamber we create a larger temperature differential to drive the engine, and the efficiency can
be future increased by increasing the number of tubes connecting the hot and cold spaces,
along with the number of regenerators, and adding fins to increase the surface area of
these tubes to allow for heat transfer. Did I say simplified? Sorry I meant easier to read. Maybe I like the misery” Stirling engines ultimately fell into obscurity
as stronger steel became available to make steam engine boilers safer, but have seen
a resurgence in recent decades with the Gotland being the most famous implementation. The Gotland uses two Stirling engines that
use diesel and liquid oxygen to provide heat, which in turn runs it’s 75kw generators. These generators can run an electric motor
directly, or charge batteries that can provide a huge boost in speed when needed. All the while the exhaust is compressed and
stored on board, allowing the sub to stay submerged for up to 2 weeks vastly longer
than any other diesel power submarine. So why is it so silent compared to other submarines,
it doesn’t require much explanation as to why using an internal combustion engine using
tiny controlled explosions for power tends to cause some noise. While the the multi-billion dollar nuclear
powered submarines need to pump huge volumes of coolant to their reactors to prevent a
meltdown, causing enough noise to be detectable by passive sonar within a certain range. On top of this, recently declassified intelligence
suggest that Russian subs are using these instruments to detect the faint trail of radiation
left in the wake of these nuclear powered submarines. Giving the swedish submarine another way of
avoiding detection. This is a fascinating application of the laws
of thermodynamics. Understanding and applying the laws of science
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100 thoughts on “How a Single Swedish Submarine Defeated the US Navy

  1. Jeaaa bla bla bla the German u 32 did it all so like the French Submarine. The US Marine are not so smart to find this New Class of Submarines. And the have NO Sterling Engine for Underwather travel. Stupid Bullshit. The 2 Submarines how deliver a Fake Torpedo to the Aircraft Carrier has good Fuel Cells and a Elektrik Engine. The Diesel is only für Over Wather Travel. The Electric Motor is a Brushless Engine wiith a diameter over 2 Meter. Its Rotate Slow and has a direkt Drive to the Prop. No Gears nothing. Yea and the Gorland Class from Sweden have got a Sterling Engine but the only work Surfaced. Dived the use the Same Electric direct Drive like the French an German Sub´s.

  2. Many of the pics you show in the video (for example 1:23 and 2:07) are not the Gotland Class, they are of the new swedish model that will be even better, the A26.

    You can read more about it on Saabs webpage:

  3. The video didn't cover any attack tactics on how the Swedish sunk our ship in war games? Only how the Swedish used a diesel engine which is quieter than most engines. Which was very smart and not only silent ,but leaves no trace of radiation like most subs which can be detected? The real answer they are getting across is? "If it works don't mess with it". They just out smarted modern technology and won with a lower price tagged submarine proving that a $12.998 billion dollar Air Craft Carrier can be sunk with no problem using only one submarine. Imagine what 4-5 subs could do to an entire armed escort of the United States Navy in a real battle? "If done right we wouldn't stand a chance a against them".

  4. Except a single Swedish submarine didn't actually sink one single ship, much less defeat the U.S. Navy. What a load of shit.

  5. Musk is building a methane rocket/sub that will orbit earth and then travel to the ocean floor using methane and refuel at the under water volcanoes.

  6. Strange insults from a fake US SAILOR some hours ago … PS Here in Rionero In Vulture, someone (corrupted one) is just spying my connection. Vittorio Brienza must be arrested. Potential National/Global Security issues. Thanx for your attention.

  7. Australia’s 30 years old Collins class sub also sailed undetected under a US carrier battle group sinking the carrier in a war games exercise

  8. So what's the trade-off with the sterling engine vs nuclear? power output, fuel capacity, engine size?
    I imagine if the Swedish model was universally superior the US Navy would've started making these exclusively.

  9. Almost every Nation in Europe did that…..Carrier are totally overrated I mean OK if you are in War with a 3rd World Country it's nice

  10. Now ask yourself why there would be as I write this statement 9.8 thousand dislikes for this video. Its not offensive to anyone, its interesting, it's totally fact based and presented very well. So why as I speak nearly 10 thousand dislikes?
    I'm just speculating here but I bet at least 9.7 out of the 9.8 thousand are Americans believe everything their media says about their country being the best in the world at absolutely everything. In my opinion this is more embarrassing than a great piece of intelligence and engineering hitting an US navy Aircraft carrier. Surely credit where credit is due, the Gripen isn't bad either by the way. It'll be good to see how the fighter that the UK, Sweden, Canada also looking like Japan is coming aboard as well develop this new fighter aircraft. 4 nations with proven Stella aircraft designs in their own right.

  11. Real submariner here. Served 1999 to 2003 on USS Florida SSBN-728 and USS Asheville SSN-758. Rank/rate STS3(SS).

    We are all required to become Qualified in Submarines (the "SS" part of my rank/rate), an intellectually rigorous certification requiring months of study (while you are doing a highly stressful job, staying awake for 24-48 hours at a time is typical) and a 2 hour board interview by a nuclear trained officer, a nuclear trained senior enlisted person, and a non-nuclear trained senior enlisted person. I was enlisted, so my Dolphins are silver, but I was required to know the same things in order to earn my Silver Dolphins that an officer must learn to earn their Gold Dolphins. (the main difference is that an officer, in addition to becoming Qualified in Submarines, also has to be trained in operation of the nuclear reactor, which requires going to Power School, and requires calculus. But that's beyond the scope of being Qualified. I do know a lot about the reactor just by virtue of having become Qualified.)

    The main problem with diesel boats is range. They can stay submerged for weeks or a month, but only if they are going very s-l-o-w-l-y.

    A diesel boat couldn't cross an ocean in an any reasonable length of time (or in most cases at all) while remaining submerged. They would have to come to periscope depth and snorkel to charge the batteries. At which time, everyone in a 20+ mile radius knows where they are. Yes, this includes "air independent propulsion", to which we in the nuclear Navy say "lmao"….air INDEPENDENT propulsion is nuclear….we can stay submerged, theoretically, for 20 years. In practice it's 90 days because we usually only bring about 90 days of food aboard. I personally have been underwater for 87 days.

    My point is that, while it is possible for a small battery powered submarine which was already in the area to attack a USN battle group and sink a ship or two…they aren't going to be able to leave Iran (for example), go all the way to San Diego (for example) and remain undetected. We would hear/see them coming and kill them. If you guys only knew half of what we do on submarines and what is prevented every day…but, "as a matter of national policy, the United States Navy does not discuss submarine operations", hence the nickname "The Silent Service". So, yeah, diesel boats are a joke in the modern world.

    Think about it…the countries that rely on diesel boats don't have what we call "blue water Navies". They instead have "brown water Navies"…which means that they're largely just defending the area around their coast.

    They don't have the vast power and global reach of the United States Navy.

    The US, French, and British Navies will never return to diesel powered submarines because we want to be able to go anywhere in the world and remain undetected. We want to stay underwater for months at a time. This requires a nuclear reactor. In World War II, we had diesel boats. But back then, there weren't nuclear boats to worry about. A French submarine is quite capable of going from Toulon Navy Base (near Marseilles), all the way to the Iranian coast, remaining underwater and remaining undetected for the entire journey. The same is NOT true of a diesel boat from Iran's Navy.

    Nuclear is green, by the way. It does not emit any air pollution and it produces a LOT of power for a small land area. If you reprocess the waste and use breeder reactors, it is basically a renewable resource.

  12. So Australia buys shitty french subs, that have to be converted from nuclear to diesel when we could lease some swedish subs instead!!!

  13. US state: SWEDEN GO DIE
    Sweden:u CAnT dEFeAt kInGd0m oOf bÖrK
    US goverment:d0nAlD TRuMp iS c00l
    bÖrK eMpIrE:i have conquerd Afro-euroasiaoceania.s.america boi

  14. A very key piece of information that’s missing from this video is that any sub, from any country, can do this to any other country’s fleet. While it is cool that this submarine uses technology that was forgotten by time, this submarine wasn’t doing anything that other submarines can’t do.
    This video was released 3 months ago and is referencing information from almost 5 years ago. It would be interesting to see if anything has changed in these war games since.

  15. I find it funny how all of the people watching this from America are roasting the UK and vice versa. You guys know we are allies, right?

  16. is not the only case, several other countries have "sunk" US carriers with diesel subs, most during exercises, some by chance…

  17. Finally! Sweden was so fucking borring that i was embarressed to be born in sweden, our fucking king goes to strip clubs and the country is lead by communists, now i'm proud!

  18. Ok, so Sweden is now in war against the US? That's what I got out of this whole thing. Anyways. Good luck Sweden if your trying to go to war against the US, you may have the sea… BUT we have nukes and the marine Corps that will get you by land. We also have hornet jets sooooo good luck with that Sweden I hope pewdiepie is safe there.

  19. There's a video saying why you will never be able to sink a U.S. carrier. I wonder how long my post will stay up before being deleted if I posted a link to this video there?

  20. Swedes are no NATO member but neutral, thus don't play wargames with U.S. ships. In fact it was a German submarine, and the Germans use to build their own submarines. Hope that helps.

  21. (CVN-76) USS Ronald Reagan has never sinked, he is still in active service and is still operational. Do you for real think a Carrier can be sunk that easy?

  22. not since the 2nd world war has the us military won anything. . . year after year, they just are very good and killing innocent people and destroying their cities, to justify their trillion dollar budget. the very worst kind of parasites.

  23. When does a carrier group stop near a coast? This is not a real war scenario as a carrier group can easily outrun a diesel powered submarine.

  24. That's a bad graphic of stirling engine, though to be fair he did give a disclaimer. Also it was just a paintball game, it wasn't really sunk.

  25. There was a los Angeles class real close, in a shooting war it would never get close enough…the video left that part out

  26. 4:45 To provide heat or cold depending on their needs, it just needs a temperature gap so both extreme can work as well.
    Therefore, it's a fuel-powered electrical submarine without battery?

  27. This is nothing new.. An italian sub A212 Todaro class did the same..Also an Australian Collins class did it..And even a Portugues sub did it..Portugues!!! WTF!!!

  28. This is how the swedes won:
    Swedes Submarine: We give 5 boxes of toblerone if you surrender.
    US aircraft: We surrender.
    Swedes: Gives 5 boxes of Marabou chocolate.
    US: This is not toblerone.
    Swedes: We are not Switzerland.

  29. USA and China too, believe too much in big surface ships, not the russian marine doctrine who keep on to believe in silent submarines.

  30. Very impressive. And grand strategy can further enhance the utility of this and other
    American and allied military assets.

    The American Canal between Brownsville and San Diego, hard by the GREATEST OIL
    STRIKE IN HISTORY, will vastly improve global trade routes between Asia and
    Oceania on the one hand and Europe and Africa on the other. A significant part
    of this improvement will be a reduction in traffic through South China Sea and
    the Persian Gulf, Strait of Hormuz, Gulf of Oman and the Red Sea. Their
    strategic significance will be correspondingly reduced.

    The American Canal will be a sea-level seaway like the Suez Canal, with no need for locks.
    Transit will be much faster than through Panama's canal with its 12 locks. Submarines can
    transit submerged. Fuel can be taken on at Brownsville, San Diego, and other nearby points.

    The American Canal will compound the utility of American and allied military assets
    by greatly facilitating their deployment and redeployment world-wide. It can be accessed
    by going to San Diego or Brownsville, or from the Port of Quebec City through the Saint
    Lawrence Seaway, the Welland Canal and the Great Lakes, and through major rivers and
    inland canals to the Port of New Orleans, thence to Brownsville.

    Panama’s canal has been key to the American world order for a century, but it’s now
    under the control of PRC.

    Further see website
    It can be accessed by simply clicking on the name.

  31. I was in the sub service , this was common for us.We were to test aircraft carriers defense against submarines. The captain of one carrier did not believe we were sitting under the carrier until we fired a flare. We laubhed watching there fire control crew chase the flare around on there flight deck.

  32. Mistake if you rely on passive sonar when you know you have silent enemy in the vicinity. Nothing is as concerning to a sub captain as active sonar. Impossible to hide from unless you’re concealed by another vessel or bottom structure. Anything else and you’re toast.

  33. All aircraft carriers all vulnerable to submarines, which is why they never go anywhere without a carrier group consisting of destroyers, attack submarines, etc. Subs are always a threat to any vessel. That's why they are referred to as the silent service

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