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  • We all know what happened to the Titanic, (and if somehow you don’t know, well, have

  • we got some videos for you!)

  • Anyway, when I was a lot younger, maybe in my 20’s ha, I was wondering every time I

  • heard the storywhy hadn’t they just hit the brakes as you would do with the car?

  • Well, of course, because ships don’t have brakes!

  • Butwhy?

  • The first thing that comes to mind is that ships move in waterduh! – how do you

  • even brake in water?

  • But then you need to remember that even airplanes have something similar to brakes, and they

  • work to slow down a plane in the air!

  • It seems like it’s not that simple, after all.

  • Every kind of brakes out there works because of friction.

  • When you hit brakes in a car, it stops because brake pads tightly grip wheelsrotors and

  • cause a lot of friction, basically restricting them from moving at all.

  • And if wheels stop, they cause friction with the road, and more friction means less speed

  • until the car eventually stops.

  • As you can tell, something like this won’t possibly work in water.

  • Motorized ships are mostly driven either by the motion of propellers or by a jet stream

  • of water shot from the nozzle.

  • Simply stopping those won’t produce nearly enough friction with water to effectively

  • stop the ship.

  • Ships still have brakes, though, they just need a lot more to properly work.

  • To produce more friction, the first thing a ship needs to do is to reverse her thrust.

  • This is much more efficient with jet engines with controlled nozzles and less so with propellers.

  • And if were talking about a big modern ship, you can be almost certain she uses propellers.

  • Reversing the rotation of propellers will start to slow the ship down, but the heavier

  • the ship, the harder it is to stop.

  • They are slow to muster speed, but inertia doesn’t let them decelerate fast enough.

  • It seems the water itself is the main reason why it’s impossible to use brakes on a ship,

  • but in reality, the clever use of water’s properties is the key to stopping it.

  • The friction with water depends on three main factors: the surface of the ship, her velocity,

  • and viscosity of the water.

  • Velocity, viscosity?

  • oh boy!

  • You can’t do much with water viscosity, obviouslysort of the thickness of it

  • -- it will stay the same no matter what.

  • The ship’s velocity, though, is another matter.

  • Imagine a ship with a velocity so huge it almost reaches infinity!

  • Funny thingshe won’t go anywhere fast, because there is a paradox at play.

  • (A paradox is where two ships offload their passengersno not really).

  • The conflict here is that the bigger the velocity, the more the power with which water will drag

  • this ship back because the friction and the water resistance will also almost reach infinity.

  • Meaning, it’s not really useful in stopping the ship.

  • But one thing you still can controlthe wetted area of the ship.

  • Some ships have so-called stabilizer fins.

  • Submerging those underwater will help the ship to slow down.

  • These are actually the closest ships get to having brakes because there is one kind of

  • brakes that operates similarlyair-brakes.

  • Most jet airplanes have a special kind of spoilers that allow them to slow the plane

  • down significantly by increasing the drag of air around.

  • Stabilizer fins don’t stand against the mass of water coming into them, but they expand

  • the wetted surface and slow ship down this way.

  • If you would decide to put brakes like that on a ship, once again the water won’t have

  • it and will show its anger.

  • Ha ha angry ship.

  • Imagine a spoiler coming from the bottom of the shipit will meet an incredible pressure

  • from the water.

  • A mass of water pressing on the brake would be so huge there is simply no way it won’t

  • break off eventually.

  • Even if were able to make an unbendable and unbreakable water-brake spoiler, well

  • meet another problem.

  • Water pressing on the spoiler will simply force a ship down, maybe even submerging her

  • nose underwater!

  • More fantasy than anything, but anyways, you can be sure that maintenance of these things

  • would be too expensive.

  • And you would need to have a whole team of scuba-divers for that at all times during

  • the trip, imagine how inconvenient that might be.

  • A much better decision is to start turning the ship.

  • While propellers provide a reverse thrust, the ship’s inertia is still moving it forward.

  • All ships are made so that they basically cut water in front of them, and their streamlined

  • design lowers the friction.

  • When the ship is turning, she reduces this advantage and the speed goes down.

  • In general, ships don’t even need emergency brakes.

  • There is usually enough space to make a maneuver even without reversing thrust, and to stay

  • on the spot ships deploy anchors.

  • I know what youre thinkingan anchor is the brake stop were looking for!

  • But this strategy is best left for action movies.

  • Should an anchor get a grip on the seabed, it won’t move an inch, and this will result

  • in a huge dunk for a ship.

  • This can quickly turn into a full-blown disaster.

  • The only way to implement that strategy is to combine it with all the previous steps

  • reverse engines, start a sharp turn, and when the speed goes down, the anchor is released

  • on the side of the ship’s turning.

  • It will only work if the cable of the anchor or the chain is not stressed too much, and

  • is more suitable for smaller vessels in general.

  • If everything’s done right, the ship will spin around the point of the anchor drop,

  • but won’t go any further.

  • Still, this way of stopping a ship is awfully -- extreme, and if a mistake were made, it

  • can do more harm than good.

  • Most of the time lesser ships will use a cycling method to lose all the speed.

  • Just laying rudder as far as you can sounds better than risking your ship sinking because

  • of an anchor.

  • You may think things are much better for small yachts and motorboats as they are much more

  • maneuverable, but they also go faster.

  • And the bigger the speed, the more the distance you go before you can stop.

  • An average time one would need to react and slow down the boat is more than 5 seconds.

  • Let’s imagine an average 30 ft long boat that goes on 50 mph.

  • 5 seconds will be enough for this boat to go for another 12 times its own lengths.

  • That’s a recipe for a disaster.

  • If two boats head towards each other at a similar speed, the distance until the crash

  • will cut in half, and the collision will be almost inevitable.

  • Fortunately, an occasion like that is improbable.

  • No one leaves rudder without attention while going at full speed, and most of the time

  • other vessels are clearly visible in the sea.

  • But another thing does pose a great dangerships come in different sizes.

  • That means it’s much harder to tell how far from you is another vessel.

  • It may be a big yacht really far away, or a small boat and already too close.

  • It’s hard to tell in the sea, especially if bad weather comes into play.

  • The lack of an effective way to stop is also the reason why ships have good signaling systems.

  • Few airhorns can be louder than the one of a shipit’s hard not to get startled

  • by one, let alone ignore it.

  • Another way a ship can let everyone around know that it’s here is signaling with projector

  • lights.

  • These can shoot right through the darkest night and the thickest fog.

  • So overall ships can’t stop in place, because water won’t let them do that.

  • But seamen learned how to avoid trouble related to that.

  • Being warned is much better than doing risky moves to prevent trouble.

  • And no, the TV anchor people you see on the news, did not get their starts working on

  • ships, just so you know.

  • Hey, if you learned something new today, then give the video a like and share it with a

  • friend!

  • And here are some other cool videos I think you'll enjoy.

  • Just click to the left or right, either one -- and stay on the Bright Side of life!

We all know what happened to the Titanic, (and if somehow you don’t know, well, have

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