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Re:Suez Canal says traffic in channel resumes after stranded... by HeyLaughingBoy on Monday March 29, 2021 @12:18PM (#26624110)
>the hydrodynamic effects of these large ships in relatively shallow and narrow canals is underappreciated

I'm really surprised I haven't seen this mentioned. A long time ago, I was trained as a merchant ship's navigation officer. One of the things we were taught (but unfortunately had few opportunities to practice), was using "bank cushion" or "bank suction" to use the hydraulic interaction between the hull and a narrow body of water like a river to navigate tight curves. These days, there are simulations that I'm sure capture these effects to it's easier to get some experience with them.

Of course, in the case of the Ever Given it seems that the grounding was mainly due to not compensating for the strong cross winds.

Re:Suez Canal says traffic in channel resumes after stranded... by EricE on Monday March 29, 2021 @02:16PM (#26626000)
That and going ridiculously fast during a sandstorm.

Juan Brown/Blancolirio channel has a good overview and he touches on hydronic interactions you reference too: https://m.youtube.com/watch?v=5iyn2q6s1Sk

Re:Suez Canal says traffic in channel resumes after stranded... by SPACE_LAWYER on Monday March 29, 2021 @11:06PM (#26630902)
I learned about the bank effect from this article

https://www.ft.com/content/171c92ec-0a44-4dc5-acab-81ee2620d...

Re:Suez Canal says traffic in channel resumes after stranded... by kalium-xyz on Tuesday March 30, 2021 @06:22AM (#26632948)
There is one thing I cannot find an answer for: Why did it draw a penis?
Re:Suez Canal says traffic in channel resumes after stranded... by shadowgovt on Tuesday March 30, 2021 @10:14AM (#26634823)
Boredom. Because of covid-19 and the fact that no particular nation is required by maritime law to take on shoreleave-seekers, crews have been at sea for between 2 to 3 times a standard rotation. You find your own way to make your fun.

It is pretty funny though. I have to imagine the captain realizing his track had been discovered is every developer who ever put a comment like /* this is stupid but I'm doing it because my boss is also stupid */ somewhere in a million lines of code, thinking it would never come up in an audit.

Re:Suez Canal says traffic in channel resumes after stranded... by rswail on Tuesday March 30, 2021 @12:49AM (#26631357)
> ... not compensating for the strong cross winds.

Not compensating or not being able to compensate? One implies negligence, the other unavoidable.

Re:Suez Canal says traffic in channel resumes after stranded... by willyt on Tuesday March 30, 2021 @03:53AM (#26632144)
> Unavoidable

Not really, weather forecasts are readily available and windage calculations are a thing.

Re:Suez Canal says traffic in channel resumes after stranded... by Jenk on Tuesday March 30, 2021 @07:34AM (#26633378)
Oh gosh why didn't the expert sailors whom all have many years of experience think about this trivial matter?

Or could it be that navigating a 400mx60m, 220,000 tonne, 60m tall ship through a canal that is barely double the width with only 4m clearance is just a tad more difficult than that?

Re:Suez Canal says traffic in channel resumes after stranded... by willyt on Tuesday March 30, 2021 @09:40AM (#26634472)
Well quite, that's why they might have waited for more favourable conditions instead of trying to take such a big ship through in force 7 'near gale' with poor visibility due to a sandstorm. Seems like a risky thing to do, no? Here's the risk assessment: Can you see where you are going? No. Is it harder to go in a straight line than normal? Yes. Is there anything nearby to hit? Yes.

But the crew of the ship never do close quarters manoeuvring anyway it is the job of the local pilot to get the ship to near to the dock and tug crews who berth it. Maybe in the future the canal will change their risk assessment to hold ships this large when the weather conditions are unfavourable. Or maybe this is at the pilot's discretion already, but there was a 'human factors' issue as there is a post elsewhere suggesting that there might have been some friction with the pilot who was meant to be giving helm orders but was refusing to do so? Who knows?

Re:Suez Canal says traffic in channel resumes after stranded... by InitialLastName on Tuesday March 30, 2021 @09:59AM (#26634669)
I don't know if you read this account that was posted here last week [0], but you'll note that there is quite a lot of "pilot's discretion" going on, mostly their discretion to say "that's enough cartons of cigarettes". They do mention wind conditions delaying them, but it's not clear what the threshold might be (or whether a sandstorm might kick up suddenly).

[0] http://www.sailsafely.com/suez_canal.htm

Re:Suez Canal says traffic in channel resumes after stranded... by HeyLaughingBoy on Tuesday March 30, 2021 @05:48PM (#26640997)
As long as we're idly speculating...

Vessel has a schedule. Has to arrive at a certain berth at a certain time and is expected to only stay there for a certain maximum number of hours because another vessel will be arriving to take its place. Especially if they're already running late, there will be a lot of pressure to keep that schedule and that can lead to doing things that are usually safe, right up until they aren't.

The history of transportation, hell, the history of Mankind, is full of examples.

Re:Suez Canal says traffic in channel resumes after stranded... by ArnoVW on Tuesday March 30, 2021 @06:32AM (#26632993)
I believe the ft article says that they had 30 kts wind, and steered 'into the wind' to compensate. And since they were in a narrow canal, a sudden lull in the wind was enough.

That doesn't contradict the 'going too fast' though. Just like we don't drive 55 mph in a residential neighborhood, thinking 'if a kid runs into the street that is not my fault, it was unforeseeable'.

Re:Suez Canal says traffic in channel resumes after stranded... by Red_Leaves_Flyy on Tuesday March 30, 2021 @06:55AM (#26633124)
With a ship of this size couldn't they have the same problem if they go too slow?
Re:Suez Canal says traffic in channel resumes after stranded... by op00to on Tuesday March 30, 2021 @07:43AM (#26633440)
Yes. The ship needs to have a certain amount of water going over the rudder to effect steering.