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The secret language of ships

CalChris
15 replies
2d1h

The article mentions the Bulbous Bow but it doesn't really explain it.

A ship going through water has hull drag which shows up as a bow wave. This drag is a (decreasing!) function of hull length (sqrt(LWL)). Longer boats have less drag. What the bulbous bow does is it creates a counter bow wave which further reduces this drag. However this magic only works at a specific speed tuned for this hull.

On the San Francisco Bay, for example, a container ship will leave the container port (Port of Oakland) at a slow restricted speed (5 knots) inside the Bay. But once she exits the Bay and the shipping channel and hits the open ocean, she will increase her speed to maybe 25 knots to hit that tuned speed with less hull drag and efficiently cruise across the Pacific.

However, the shipping industry noticed that no one wanted to pay for that speed. Enter Slow Steaming. Boats could be retuned for a slower but more fuel efficient speed, maybe 20 knots. The industry literally took existing ships into dry dock and re-nosed them. This meant transits took longer but also used less bunker fuel, the cheapest and worst fuel which is only allowed to be used offshore. This both saved money and reduced pollution.

https://en.wikipedia.org/wiki/Bulbous_bow

https://en.wikipedia.org/wiki/Slow_steaming

pests
4 replies
2d

It's not an article about ships and their parts. Its an article about how ships communicate things to each other - thus the focus on markings, writings, etc.

gumby
1 replies
1d22h

FWIW I didn't interpret that first sentence of the comment as criticism of the article.

pests
0 replies
1d22h

Oops, I may have too strongly. I agree it's still interesting.

chrisatthestudy
1 replies
1d23h

Nevertheless it's an interesting addition, and I appreciate it.

pests
0 replies
1d22h

Yes me too, I was cranky this morning. Nice addition.

helloooooooo
3 replies
1d16h

Bunker fuel isn’t used anymore.

SoftTalker
1 replies
1d14h

What is done with it? It was my understanding that bunker fuel was basically the remains of crude oil after refining. Has refining improved to where there is no significant remainder in the process?

bluGill
0 replies
1d1h

Bunker is more like unrefined crude. It isn't completely unrefined as they will take out the really valuable parts, but they do minimal refining.

amiga386
0 replies
1d13h

https://www.iea.org/reports/oil-2021

In 2020, due to the Covid crisis and a decline in international trade, bunker demand is estimated to have fallen by 4.3%. As the new IMO rules were introduced, we estimate that higher sulphur fuel oil (HSFO) consumption more than halved, to 1.1 mb/d as ship operators switched to marine gasoil and very low sulphur fuel oil (VLSFO) to comply.

In the same document, it estimates global demand for residual fuel oil is about 6 million barrels per day (compared to around 100 million barrels per day for all oil products). That's a lot of consumption for something that "isn't used any more"

Cthulhu_
1 replies
1d6h

Would actuators on the bow help, or is that too fragile and error prone given the abuse it gets?

CalChris
0 replies
17h53m

The bulbous bow can already get 15%. There are bow thrusters on cruise ships but they're used for maneuvering.

https://www.sciencedirect.com/topics/engineering/bulbous-bow

15457345234
1 replies
1d14h

25kts for a container ship was really flying even before the days of slow steaming, that's passenger speed.

CalChris
0 replies
1d13h

Fast container ships, they still exist with speeds of even 29 knots. But they're for shippers who pay for that speed.

https://www.freightwaves.com/news/maersk-container-ships-big...

fatbird
0 replies
1d

Isn't "slow steaming" just what passenger airplanes do with cruising speed? There's an optimal point on the speed/fuel consumption curve that minimizes fuel use, and this is what ships are doing, isn't it? Or is there some other consideration for ships that makes the slow steam speed optimal beside fuel consumption?

amiga386
0 replies
1d1h

If people are interested in ships, their parts, how they work, and so on, there's a fabulous Youtube channel called Casual Navigation [0] which has simple and informative videos on lots of topics, including bulbous bows [1] and slow steaming [2]

[0] https://www.youtube.com/@CasualNavigation/videos

[1] https://www.youtube.com/watch?v=6FrCusDG41U

[2] https://www.youtube.com/watch?v=VjpGidILzb0

rob74
14 replies
2d2h

See the crew members up on deck, at the far left and right of the photo? They’re actually dummies dressed as mariners, meant to fool pirates into thinking someone is always on watch.

The dummy crew complements the skeleton crew...

bmelton
12 replies
2d

I watched a documentary (I think it was "Stolen Seas") about a cargo ship that had been captured by pirates, held captive for (iirc?) months. After they were eventually released, the documentary captured their passage through the same Somali sea where they were captured last time.

They turned all their steam exhausts to point out and blast everything on the upper deck. Took giant ropes, wrapped them in barbed wire, and tossed them ashore to bounce around in the seas to discourage any small vessels from coming near. I'm remembering this because I think they had zero people on deck (opposite of the mannequin strategy) -- as due to the steam, it would have been wildly unsafe to be there.

In short, their preparations were considerably more thorough, but I can't help but wonder if they'd have considered mannequins if they'd thought of it.

ok_dad
10 replies
1d19h

They could just secure all the hatches and redesign any above deck elements to be locked down as well, kinda like how a secure door fixed aircraft hijacking’s. Just keep the crew inside behind locked steel doors! You don’t really need windows, a few cameras would be fine to drive with. Pirates can come onboard but couldn’t do anything from the deck in this case.

alexwasserman
8 replies
1d17h

I’d guess here on a boat out at sea, a long way from rescue, you’re more at risk of someone with a cutting tool, explosives, etc breaking in. After all they have days till you can steam to a safe port to break in. They’re armed pirates, they’ll just cut open/blow open a door.

People don’t want to blow up planes while in them, and can’t take heavy tools through security checks. Boarding ships at sea comes without those draw back.

IG_Semmelweiss
7 replies
1d11h

Power tools and portable power may be too expensive for a local, upstart pirate.

guappa
3 replies
1d9h

Weapons cost more anyways… if they can afford weapons they can afford tools.

Cthulhu_
2 replies
1d6h

I dunno if they cost more, I'm reading an AK-47 can go for like $150, and they're built to last.

bergie
1 replies
1d6h

As far as I've understood it, the pirates don't buy their own equipment. Instead there is a "Venture Capitalist" somewhere like UAE funding the trip.

A colleague of mine was on a navy ship that captured a boat full of pirates off Somalia, but it's been a while and my recollection of the details they found out is hazy.

bookofjoe
0 replies
21h47m

Pirates ATTACK The WRONG US Navy Ship and Then THIS HAPPENED...

https://youtu.be/QCqNtLdqXi0?si=7L8WuN8qjn7YT7Nn

vkou
0 replies
1d11h

They aren't. Pirates aren't cavemen equipped with stone knives and bear skins.

acyou
0 replies
21h25m

I don't think they would be interested in Ryobi, they would want to be using oxyacetylene torches. The effect would be something like this: https://www.youtube.com/watch?v=yOgKwKFG4Z0&ab_channel=Quote...

Given the large ship breaking industries in some of these areas, I think these would be pretty easy to come by, and they are very portable (though I wouldn't want to be the one hauling the tanks up a rope ladder over the side of a ship).

Cthulhu_
0 replies
1d6h

These aren't upstarts though, piracy is an established practice and power tools are relatively cheap.

two_handfuls
0 replies
23h28m

Pirates want to negotiate with the boat owner for release, they don’t need to control the boat for that - it’s enough to stop it. Which they can easily do if they have physical unrestrained access and plenty of time.

bookofjoe
0 replies
21h50m
TeMPOraL
0 replies
2d2h

LOL, like an anti-pirate version of a scarecrow. Or that pigeon on the rooftop of a building in my area, that I'm 99% sure is a hidden camera or something, because it's always there and I've never seen it move (and it isn't the anti-pigeon dummy, because those mimic predators).

teddyh
5 replies
2d1h

Now do USB cables.

bookofjoe
4 replies
2d
teddyh
3 replies
2d

Does not cover USB 4, nor does it show any of the symbols or their meanings.

bookofjoe
2 replies
2d

I apologize for failing to provide the information you want. I will try to do better in the future.

bookofjoe
1 replies
2d
teddyh
0 replies
1d23h

Very nice! That’s more like what I was after. I also found these, which seem official:

<https://www.usb.org/sites/default/files/USB-IF%20Integrators...>

<https://www.enablingusb.org/certification>

arethuza
5 replies
2d1h

Where we live we have great view over the Firth of Forth - which is a reasonably busy waterway.

The find the full LPG tankers making their way out to the open sea fascinating as they always have a gaggle of protective tugs around them - including one going backwards behind the tanker with a cable to the stern of tanker - presumably to stop it in a hurry!

NB Yes I do wonder about the BLEVE risk - but the centre of the shipping channel is at least 2km away which you'd hope would be OK... ;-)

closewith
4 replies
1d7h

including one going backwards behind the tanker with a cable to the stern of tanker - presumably to stop it in a hurry!

To act as a brake, which allows the tanker to run higher RPMs pushing more water over the rudder to increase steering authority, and also to directly steer by pulling the stern around in some cases.

NB Yes I do wonder about the BLEVE risk - but the centre of the shipping channel is at least 2km away which you'd hope would be OK... ;-)

After the 2011 Tōhoku earthquake and tsunami, there were five BLEVE incidents with LPG tankers. Ships with up to 5000 m^3 of LPG caused fireballs of up to 500 m in diameter (1).

The largest LPG tankers into Grangemouth carry ~40,000 m^3, so if you see one on fire, I wouldn't hang around.

(1) https://www.sciencedirect.com/science/article/abs/pii/S09504...

arethuza
2 replies
1d6h

"pushing more water over the rudder to increase steering authority"

Thanks - that is fascinating - I had thought that the tug was actually pulling backwards while the ship was moving forwards.

"I wouldn't hang around"

Thanks for the advice :-)

closewith
1 replies
1d5h

I had thought that the tug was actually pulling backwards while the ship was moving forwards.

They might be doing that at very low speed, but in general an aft tow is very dangerous for a tug as it can be pulled under very easily, especially if it goes abeam/side-on to the direction of travel. Also in shallow water like some ports and estuaries, the force from the tug's props/thrusters can push against the vessel under tow cancelling out much of the force from the tow (one of the many reasons that tugs prefer to push than pull).

When a large vessel performs an emergency brake, it does so by pushing the rudder hard to one direction to use the additional drag from the hull during turning followed by going hard over the other direction to return to the original heading (it's rare a ship will have to perform an emergency stop anywhere where it has room to continue the turn - otherwise it would just continue on the new heading). This trades speed for lateral displacement and is extremely effective (although very hard on the steering gear).

However, in a congested TSS/shipping lane or river/estuary, that lateral displacement may not be available. In that case, you counter intuitively will see a tug that has an aft tow line assisting the vessel to brake by pulling 90 degrees to the side of the direction of travel/braking. This is to allow the ship to rotate in the water to push more of it's hull into the direction of travel which increases drag. Normally the resulting force would also turn the ship (ie, change the Course Over Ground, not just the heading/direction of the bow), but the tug can minimise this by pulling the stern in the opposite direction. This allows the ship slow very quickly with little lateral movement.

arwineap
0 replies
23h47m

recreational sailor here - Any resources to learn more from the commercial side like this?

Very interesting

kitd
0 replies
1d1h

Visible here too (the tug on the left of picture):

https://photos.app.goo.gl/eeLNWRk7H8WvUkBt9

Obscurity4340
5 replies
2d2h

I want to see a treatment of The Secret Lives of Huge Ships,

Edit: and maybe assorted biopics on their Kap'ns. It would amazing to have a workplace comedy of Huge Ships equivalent to The Office, the Taliban too

UniverseHacker
4 replies
1d4h

The sea can’t be fooled by BS, unlike a lot of white collar jobs, mariners that don’t know what they are doing don’t survive. So I doubt The Office style situations are happening much at sea.

Obscurity4340
2 replies
1d3h

I agree but how funny would it be to have the mariner equivalent of that? Does anythingeven approach the awkwardness of being at sea and having the absurd potential for "Nautical office politics"?

Imagine bro. Thats why I mentioned the Taliban. There was an article about how mundane life is for the fighters now they they have to be bureaucrats and actually run the damn show. They ran all the damn actual bureaucrats in Kabul that were nominally running the show and now they have to fill that power/responsibillity vacuum and the whole article was beyond surreal on account of its stranger-than-fiction palpabillity or implications

Edit: its like everyone just dropped the criminal cases with Trump or he accepted some mega omnibus plea deal with everyone with the criminal penalty being he needed to work at the DMV if the most MAGA state so he actually had to deal with the day to day negative effect he's had on governance and the constituent bodies that are required for its provision of necessary services and functionz, no pay and no golfing. Golfing == prison

Edit: the SCOTUS would need to work their Magick and ensure it wasn't ruled as "cruel and unusual punishment" and thats pretty hard to ensure unless the government "legally" bribes Thomas and Alito and possibly Barrett to shut the fuck up and take the L

UniverseHacker
1 replies
1d1h

That would be hilarious

Obscurity4340
0 replies
23h16m

Everybody just wants closure and for The Donald to shut the fuck up and accept hes poor now. He'll be fine

oh_sigh
0 replies
22h1m

There are a few important roles that need to be filled by competent seamen, but the rest can just be goof balls. Check out "Whale Wars"

throwawayForMe2
3 replies
2d

They should add a section on the language of a ship’s lights at night.

Animats
1 replies
1d9h

Here's the U.S. Naval Academy's guide to the rules of the road.[1] Section C has the lights. For most ships and boats, it's reasonably simple - red, green, and white visible in 120 degree arcs, with white visible from the rear, plus a high white masthead light for some vessels. The complicated cases mostly involve work boats doing something - fishing, cable-laying, towing, etc.- where there is a hazardous area around the vessel and movements are restricted.

[1] https://www.usna.edu/Sailing/_files/documents/2019_OSTS_Docu...

oakmad
0 replies
1d7h

I love there is a slide for WIG - wing in ground effect

_whiteCaps_
0 replies
22h2m

Weems and Plath make a nice tool for that: http://www.weems-plath.com/LIGHTrulesandROADrules/Lightrule....

newsclues
1 replies
2d

Technical language isn’t really secret and is a great way (social engineers) people can fool others that they belong, simply by talking the right way.

scubbo
0 replies
1d22h

A less cynical way of putting this would be - it's delightful that even non-experts can enjoy learning about technical jargon and the underlying processes they reflect!

NoboruWataya
1 replies
2d2h

Very good article, no BS just clear and comprehensive explanations of the various features and symbols.

alfredpawney
0 replies
1d21h

I also liked this article which goes deeper no pun intended into the invention of the Plimsoll Lines https://www.linkedin.com/pulse/story-samuel-plimsoll-develop...

Cthulhu_
1 replies
1d6h

I'd love an article like this but about techies and the turbo language we use. Things like "in the cloud doesn't literally mean in the clouds", "serverless doesn't actually mean it doesn't run on a server", or "rtfm means read the f**ing manual"

laszlojamf
0 replies
1d3h

Reminds of a non-techie friend who had a shirt which said 503, which apparently was a brand name for some vaping liquid. Wasn't my first guess.

pivo
0 replies
2d2h

For years my wife and I would run around the piers near us. Occasionally we'd speculate about what these ship marks meant and I'd promise myself I'd look them up when I get home, but I never actually did. Very happy to have all those questions answered so clearly!

owenversteeg
0 replies
20h12m

One of the most awesome experiences of my life was sailing close to a cargo ship and hearing the full blast of the horn, crashing through the bow waves and marveling at the size of the ship. The size and power of these monsters is impossible to describe. Many people have seen one sit still but seeing them move from up close is completely different. The power and energy with which these massive objects move... it is as if an entire mountain sprung to life. The largest cargo ships are in fact even larger than the Empire State Building. Imagine the largest of the skyscrapers charging forward at you, churning water, pushing forward at incredible speed.

A warning to those who want to try this at home: You typically don't want to get too close to a moving cargo ship (or a stationary one with a moving propellor) as they have incredible suction power that will rapidly draw you closer like your boat weighs nothing. This power can easily capsize you or slam you into the hull with incredible speed. My boat is ten thousand pounds of steel with a powerful diesel engine, oversized for its class. Container ships move it to and fro as if it was weightless, a mote of dust on a sunbeam rudely sent zigzagging by a passing gust. Underestimate these monsters at your own peril.

kopirgan
0 replies
1d14h

Very good article. Thanks!

kazinator
0 replies
1d15h

Curious about those yellow-green, fortune-cookie-shaped objects along the lines? They’re anti-rat devices, foiling rodent attempts to scrabble from dock to line to ship.

Ah, so that's where Open Source Initiative got their logo!

jairuhme
0 replies
1d2h

This was a very nice read. One of those articles where I now have some new fun facts to spout the next time I'm by friends near a harbor. I live in Cleveland and see many ships entering the rivers to drop off cargo, will be looking for some of these markings!

hasoleju
0 replies
1d20h

I like the simplicity of the symbols. They really are international and it's interesting to see how they all have a clear purpose.

1. White rectangle above red rectangle with yellow borders: Pilot, please board here to guide us into the harbor.

2. Horizontal line through a circle: You should see this line above the water, otherwise the ship is overloaded.

3. Sketch of a bulk under water: Be careful, this ship has a bulbous bow that might be beneath the water surface.

fotta
0 replies
22h27m

Anyone that’s interested in the machinations of the tugboat industry might be interested in TimBAtSea on YouTube. He’s a tug captain in the New York Harbor and Puerto Rico moving large oil barges and his videos are fascinating to me.

andyjohnson0
0 replies
1d8h

For those interested in ships and naval architecture/history, The Lore of Ships by Tre Tryckare is an informative and (to me, at least) beautiful book. As far as I know it is long out of print, but the Internet Archive has a scanned copy for loan [1], and second-hard copies are available from the usual places. The quality of the illustrations in the IA preview is representative of the whole ~280 pages. A fascinating book.

[1] https://archive.org/details/loreofships0000unse

SandraBucky
0 replies
1d1h

I wonder how shipping industry is gonna change in coming decades. Especially in the context of more countries opting towards renewables and fully-automated ships.

Duanemclemore
0 replies
1d23h

Thanks OP - I love whenever this article comes back across the waves and give it a read when it does. While not directly related, if you want another lyrical look in to the world of containerized shipping, check out Sekula and Burch's The Forgotten Space. Well worth the watch. https://theforgottenspace.net/ Looking just now, apparently a lot of reviewers had a problem with how polemical it is. I didn't. But even if you disagree with the top line message, it's still a fantastic look in to a world (or worlds) 99% of humans will never get to see into.