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Comment by munificent | Hacker News Reader

You say that like they just got unexpectedly lucky, but all mariners are well aware of and take tides into account in their planning.

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I’d be surprised if they aimed for their ship to arrive n days before the spring tide in case it got stuck. That just doesn’t sound like an efficient operation. In this case the luck was that the high tides were relatively high when it was stuck. If we were in a neap tide, we might have had to wait longer for a high enough tide to get the ship out. (But maybe if tides were lower it wouldn’t have gotten so stuck)

P.S. it isn’t exactly clear what you mean by mariner, but plenty of sailors in the Mediterranean don’t really need to care about tides as they don’t really get them there. Indeed, you shouldn’t trust any of the early modern Greek or Italian treatises attempting to explain tides as their authors didn’t really know how tides actually behaved outside the Med.

> I’d be surprised if they aimed for their ship to arrive n days before the spring tide in case it got stuck.

That's not what I'm saying. I'm saying that after the ship got stuck, they certainly incorporated the tides into their plan for how to unstick it. If the tides had been less amenable, they would have come up with a different plan.

So their plan didn't get "lucky", their plan was predicated on the tides being part of the solution.

Without the high tides the amount of material needed to be removed would have been dramatically higher.

That’s the point and the absolute bit of luck. Without the high tides they likely wouldn’t have been able to get it unstuck as quickly. Search for slope/fill volume calculation charts - the amount of fill required to be removed as you go deeper is logarithmic, NOT linear.

It was VERY lucky they had the highest tides possible.

Did the ship crash during high tide or low tide? The tide 6 days ago when it got stuck compared to today is more important.

What? Tide mattered more now because it had a significant impact on getting it out quickly.

Luckily it wasn’t nearly as high when it beached itself - but if it had beached itself on the downslope of the peak tide instead of the upslope it very likely would still be stuck!

Tide when it crashed was not nearly as significant as when it got free.

I disagree, i think you got that backwards - the tide level at the time of the beaching has surely had an effect on at what point it started plowing and was being decelerated and subsequently how far in absolute numbers evergreen went into the rim.

Imagine getting stuck during spring tide vs low tide hich is more than 2m lower and would have decelerated the ever given earlier

Sure but the luck here is the number of days until a sufficiently high tide. Imagine a simple model where every 28 days you get a sufficiently high tide and every other day is not sufficiently high, and the ship gets stuck (after high tide) on a uniformly random day. Then the expected time until the ship is unstuck is 14.5 days and the luck is how close you are to the time the ship can get free.

It's even shorter timing than that. Spring tides occur at the full moon AND the new moon. So you get two chances every lunar cycle.

The "spring tide", the highest of the high tides, naturally occurs twice every 28 days. This is when the Sun, Earth and Moon are in a line. So the average wait would have been ~7 days.

That's not what he said.

Ship captains who sail on open ocean are well aware of tides. It is not too difficult to imagine somebody did 2+2 and figured out the tides are getting higher so in couple of days there is going to be better chance of freeing it.

Obviously they did not plan it. It is just an opportunity they used.

You talk about planning about an article about a container ship piloted by professionals ran aground.

So your saying they planned to only crash the ship during the high tide?

You do realize the canal operates during all tides?

So yes, it was absolute luck this accident happed right before the highest tides of the month.

I think you and the other poster are saying different things. You are saying it’s fortunate that a spring tide was coming and you are right. I think grand parent is saying that sailors are well aware of tides and as soon as the ship got stuck they would have been racing to meet the spring tide, which was planning and not luck.

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