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Comment by briancp | Hacker News Reader

I was in St. Simons a few months ago, and was able to see this ship first hand. It’s enormous, sitting on its side in what looks like just a few feet of water. It’s close to the shore, maybe a thousand or 1500 feet out. A temporary information placard had been put on the fishing pier explaining what it was.

At the time it was all in one piece, but you could see them attaching the lifting equipment along the length, and it was clear it was going to be cut into pieces.

It must take an enormous amount of work to build an internal framework that can support the cut section being lifted from the side. I’m not surprised it’s taking so long so salvage.

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>It must take an enormous amount of work to build an internal framework that can support the cut section being lifted from the side. I’m not surprised it’s taking so long so salvage.

Ships have to be able to withstand substantial side forces (in both tension and compression) as part of torsional loading in normal operation. There's no internal framework needed. Even if there was that would require a stupid amount of effort compared to just adding more lifting points.

It's stupid easy to figure out lifting solution in this case because this is a new enough ship that CAD models exist. If the owner doesn't have the CAD files you pay whoever you need to to get them (you just need a low detail model of the hull and bulkheads, not the high detail models that include plumbing and whatnot, those would be needlessly expensive), then import the models and then run numbers until you get numbers you like (e.g. section sizes the crane guys won't complain about and a safety factor corporate won't complain about). Then you tell the intern to use the CAD models to whip up a set of matching plates for lifting. If they have extra time on their hands maybe they'll make some random feature dong-shaped. Then you forward that attachment to the sales guy at the steel supplier you usually use.

All this stuff is routine business for the parties involved.

Until the intern decides that running a nut up 30 feet of threaded rod is silly, uses two rods, and you have the Hyatt-Regency. :-)

Context for those who don't know: https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse

Years ago, I was a computer science major at Tulane University. At the time, Tulane put CS in the school of engineering, so every first year had to take a mandatory engineering safety class. The first day of class, they turned off the lights and played a home movie that was recorded during the dance at the Hyatt-Regecy. The video cuts out right before the disaster, but there is audio from one of the musicians, and they played that.

Sitting in a dark room listening to a huge crash followed by screams of pain and terror fully instilled the importance of engineering safety in me. This was 20 years ago and I still remember it clearly.

Often I wish everyone had some mandatory class like that to teach them the seriousness of the consequences of our actions.

Your resume says LSU though...

I dropped out of Tulane after a few months.

We've made some changes since then if that's any consolation

Havens Steel Company had manufactured the rods, and they objected that the whole rod below the fourth floor would have to be threaded in order to screw on the nuts to hold the fourth-floor walkway in place. These threads would be subject to damage as the fourth-floor structure was hoisted into place. Havens Steel, therefore, proposed that two separate and offset sets of rods be used: the first set suspending the fourth-floor walkway from the ceiling, and the second set suspending the second-floor walkway from the fourth-floor walkway.

Investigators concluded that the underlying problem was a lack of proper communication between Jack D. Gillum and Associates and Havens Steel. In particular, the drawings prepared by Gillum and Associates were only preliminary sketches, but Havens Steel interpreted them as finalized drawings. Gillum and Associates failed to review the initial design thoroughly and engineer Daniel M. Duncan accepted Havens Steel's proposed plan via a phone call without performing necessary calculations or viewing sketches that would have revealed its serious intrinsic flaws—in particular, doubling the load on the fourth-floor beams.

-- https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse

When someone tries to tell my hypothetical intern about the Hyatt Regency I'm gonna use that to teach them a lesson about bike shedding. The gist of the lesson will be that "had the person who brought it up actually meant to be helpful instead of just showing off about how much they care about Safety(TM) they would have brought up that jet liner that kept falling apart because of the square corners in the hatch or some other more relevant failure story even if it is a less flashy one. We've all seen this kind of ass-kissing behavior. Some jerk does a reply-all to something with a low effort (and usually obvious) comment about how approach X would be better for <insert corporate initiative or buzzword of the month here> and everyone else has to try and hold their tongue.

I'm afraid I have no idea what you're trying to say.

("[T]hat jet liner that kept falling apart because of the square corners in the hatch" is the DeHavilland Comet, BTW.)

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