Hello science lovers, today I would like to explain something very interesting with what I came across by chance, and that is that yesterday I was watching a documentary about the arms revolution and some of the military powers when I came across something that I found it extremely curious.

For many, it is more than known the enormous power of war that the US has, all due perhaps to the incredible amount of resources and progress that have made throughout its history in terms of the development of technology dedicated to war. Well, it has been precisely these unremitting efforts (and monetary investments) that have earned them the possibility of having one of the most diverse and powerful naval forces in the world.

In fact, the U.S. Navy has a fleet of aircraft carriers so impressive that, to the eyes of the world they are the second largest air force in the world, surpassed only by guess who ... Yes, the United States Air Force.

NASA
Public Domain

Well since I have made clear the incredible power, diversity and other adjectives that can occur when we talk about the U.S. Navy, let's see what this post really is about. And is that despite its incredible power, the US navy was defeated by a Swedish submarine.

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2005 War games.

Every year, a series of strategic tests are carried out among several countries where each one can use his best war machines to win. However, these games are no more than that, a series of military exercises to be able to measure against other countries the advances in war that each participating country has achieved.

Well in 2005 when this series of military exercises were carried out, where the US took one of its best "toys" the aircraft carrier class nimitz USS Ronald Reagan, which has an approximate value of 6,200 million dollars and is powered by nuclear energy. In addition, this colossal aircraft carrier has the capacity to carry almost 200 aircraft between aircraft and helicopters, that is, twice as many aircraft as any other aircraft carrier in the world.

The surprising thing is not the incredible of the USS Ronald Reagan, the unbelievable thing is that it was hard defeated by a Swedish submarine powered by diesel. Specifically, it is the Swedish submarine class Gotland, a submarine that in theory is more modest and should not have been able to sink the American aircraft carrier but that nevertheless did. Giving a little more context the Swedish submarine is so modest that it costs the same as a fighter plane F-35 and that as I said earlier It has a diesel engine.

However, and despite its low cost, (Yes, for many 100 million dollars is little when it comes to military weapons) this Swedish submarine managed to camouflage so incredibly that managed to infiltrate inside the perimeter of the American aircraft carrier to get sink virtually, to Despite all the antisubmarine tactics and forces of the USS Ronald Reagan.

It should be noted that before the astonished that were the officers of the U.S. Navy these could not remain calm and made several rounds of military exercises in order to confirm that what was achieved by the Swedish submarine was nothing but a stroke of luck. But first of all, the results were always the same; the Swedish submarine always won and besides sinking them in all the simulations, this one remained undetectable for the greatest naval force in the world.

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In front of such incredible results, the obvious question is: How could a Swedish submarine defeat the most powerful aircraft carrier in the world?

The Swedish submarine surprised the American officers so much, that they had no choice but to ask the Swedes to rent their submarine for a year in order to make improvements to their entire fleet so that they were prepared to counter the silent threat that the Swedes had created.

Before digging a little deeper we need to be clear that the main instrument used by ships to detect submarine enemies is sonar.

The sonar is essentially a tuned ear that works like whales and dolphins do: Eco-location to create a three-dimensional map of the ocean's surroundings.

Sonars are so efficient and precise making detections that are able to determine the nationality of submarines by analyzing the frequency of operation of the alternating current that enemy submarines use.

American submarines usually use 60 Hz of alternating current, while Europeans use 50 Hz.

Well, the Swedes were able to create a submarine so silent that it is practically undetectable for the sonar of other ships and submarines.

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But how were they able to make such a silent submarine?

Despite the great advances in terms of power generation and new technologies implemented in submarine engines, the Submarine class Gotland against all forecast opt for the reformulation of an old engine and is that the Swedish submarine was the first submarine in the world to use a Stirling engine as the main generator of energy.

Stirling engines were patented by Robert Stirling in 1816, who was inspired by the boilers of the industrial revolution to create a safer machine without high pressures

The Swedish engineers designed the Gotland in such a way that it could hold two Stirling engines so that when these two engines were heated with diesel and liquid oxygen could move almost without problems generators of 75 kW and thus provide power to the entire submarine.

The way in which Swedish engineers implemented the Stirling engines was so incredible that it made it possible for submarine generators to move an electric motor directly or to charge batteries that later could be used to give the submarine a speed boost in specific situations.

Well this apart from being something really incredible because these engines in addition to generating a large amount of energy also allow it to be stored for use in any other kind of situations, also making these submarines stay submerged for 2 weeks without interruption.

In a few words, the implementation of these engines not only makes the Swedish submarine fast but also makes it extremely quiet, since by using two engines that only require the use of a combustion system based on small and contracted explosions make the noise issued abroad is practically zero.

While the submarines used by other fleets are based on the use of engines based on the use of nuclear energy which leads to the use of large pumps that provide the core with enormous amounts of refrigerant, all to prevent the destabilization and subsequent melting of atomic nuclei, but that causes these submarines to emit enormous amounts of noise which makes them easy prey for sonars.

The work done by the Swedish engineers is undoubtedly to applaud, the way in which they coupled the Stirling engines so that they would be efficient not only in the field of power generation but also so that their noise emissions will not affect the performance of the submarine in battle.

In the end, they managed to demonstrate once again that ingenuity and skill are always above how much money you can invest or how big you can make a war vehicle.

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References.

• Did Sweden Make America's Nuclear Submarines Obsolete?
• United States Navy
• Aircraft carrier
• Gotland-class submarine
• Sweden Has A Sub That's So Deadly The US Navy Hired It To Play Bad Guy
• How One Cheap Submarine from Sweden 'Sank' the U.S. Navy in 'Battle