I heard container ships have been getting bigger over the years, is that true?
100âs of ships pass the Suez canal every day and all do 7-9 knots and steer peacefully between the buoys at the canal sides. In a sand storm they all slow down and drift against the canal side. If a ship speeds up to 15 knots during a few minutes and turns into the canal side, some thing is wrong and strange. It is a pity we donât know why the ship increased speed and turned.
I sometimes think some of the old farts around here arenât really appreciative of how large container ships have become even in just the past ten years.
As said above, âthis isnât your fatherâs Oldsmobileâ. Itâs not just added length - everything is larger, including sail area, which grows exponentially with length and stack height. It doesnât take much wind to put a serious transverse force on ships this size and the extra length and beam further compound the problem when swept path needs to be taken into account (as when in a narrow channel/waterway). You canât just drive out of these situations and youâre not going to lay it alongside a canal bank.
With larger ships come larger engines, higher pitched props and very fast dead slow bells (often 6-8 kts). Steerageway can be maintained a touch below that but not by much.
Also mostly no longer relevant with todayâs mega ships: dredging anchors and warping on/off docks using spring lines. These ships are not the same machines of 20, 30, 40, 50 years ago. The waterways, in many areas, havenât gotten any bigger in that same amount of time either.
And we can take a very educated guess on why it âsped up and turned into the canal sideâ - the high winds developed a serious crab angle with a large swept path. A way out of that is to increase speed which is no problem in more open water. Excessive speed in a narrow, shallow channel can lead to bank effects, the end result of which can be a shear across the channel.
What happened to the ship itself is actually a pretty textbook case. The real rooting out needs to come in the decision to make the transit in the first place and what, if any, standards were in place to mitigate the risk.
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Werenât you talking about the rock the Evergiven was obviously stuck on causing monumental damage not long ago? So, before the ship was freed, canal side bad. Now that she is free, canal side good.
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No, I just wonder why mv Ever Given increased speed and turned starboard in the Suez canal. It is > 25 m deep without rocks. Why change speed? Why turn? Why run up on the side? Why would any ship do that?
Since you seem genuinely confused for once, Iâll try to explain:
First off, everything seems to indicate that the inital turn was to port, and that bank sheer put her hard over starboard. Having experienced this phenomenon myself (albeit in a much smaller boat of only 29m LOA), I can attest that the resultant yawing motion is quite violent, and not something you put right with a touch of counter rudder. The effect is more pronounced the bigger the ship (because the rudder is smaller in relation to the wet surface).
The initial turn was probably due to directional instability, again due to squat. When a ship squats with too little underkeel clearance, it develops a tendency to exacerbate any yawing motion. This is because when the ship rolls out of the turn, the low pressure zone at the stern gets lopsided, exerting a strong suction force on the side presented to the bottom.
This is taught in basic ship handling classes, and summarized elsewhere in a format you should be able to get your head around. Most of the people here will be able to expalin it in far greater detail than my limited undertanding permits, so itâs almost a bit embarassing to be the one pointing it out 
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I think KC put it pretty well:
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??? ms Ever Given enters the Suez canal at 8 knots, but due to squat ship yaws to port after a few minutes and to avoid hitting the port side, speed is increased to 15 knots, while turning to starboard, with result hitting the eastern canal side.
This is taught in basic ship handling classes!
A seafarer who was on a ship further ahead in the convoy told anyone wanting to listen that he experienced gusts of wind that day of up to 50 knots. The master of an LNG carrier the day prior had taken the decision to delay transiting, fearful of the inclement conditions.
But ms Ever Given entered the canal anyway on SCA pilotsâ orders.
âŚand who was I to think that I could pit my limited understanding against your limited willingness to understand?
*sigh*
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