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0 pointsconnorlu5y ago0 comments

Ships in reverse behave in ways that are non-intuitive (https://en.wikipedia.org/wiki/Propeller_walk). Depending on the direction of the prop walk it could compound the problem.

Another artifact of traditional (non-azimuth) propeller driven ships in reverse is that they have very little steering control if they are moving slowly as steering requires water moving over the rudder. In forward water is actively being pushed over the rudder due to its position behind the prop, but in reverse this flow is not as strong.

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ChuckMcM5y ago· 2 in thread

I don't disagree, the paper talks about torques as opposed to steerage.

That said, apparently this particular ship has a couple of 60MWatt bow thrusters so presumably one would use that given it has an even better lever arm with respect to the CG than the props do.

All in all, canal pilot is a highly skilled job, and I'm surprised the two pilots on this ship had this sort of accident.

elcritch5y ago

Given the enormous costs of blocking the canal I'm surprised it's not almost entirely automated similar to autopilots. Simulating the hydrodynamic and forces from local weather seem tractable to do in real-time with a few higher end Nvidias. At least to a high enough grid resolution that'd exceed pilot intuition and training.

ChuckMcM5y ago

I think you could do that on new ships. But there are a LOT of ships out there that still have like 10 people in the loop to drive them.

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