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The commercial ships are very simple and cookie-cutter[1], unlike military ships that are almost always new designs and involve complex, integrated systems such as communication, defense, hospitals, refueling, etc, etc.

So, subsequent hull numbers for San Antonio class ended up being cheaper than 100% over budget? Likewise, is it customary for STX or Chantiers de l'Atlantique or Fincanterei to have to double-check the status of every single weld in ship they've delivered, or are the owners of cruise lines tolerant of massive cost overruns && late delivery?

Generally, the first ship of any class suffers the most issues. Similar to the first version of any major OS/software release. I don't remember the per-ship costs off-hand but I'd be surprised if they were higher than the first.

Unfortunately the Navy doesn't have much choice in who builds their ships. They must be built in the US, and there are very few capable shipbuilders still left in this country. It's a terrible business to be in, so there's no incentive for companies to jump into the market because the margins are razor-thin. In fact, Northrop Grumman got out of the market a few years ago (http://investor.northropgrumman.com/news-releases/news-relea...).

(As an aside, cruise ships are still cookie-cutter compared to military ships.)

To borrow a quote from Churchill, "[the current ship procurement process] is the worst form of [procurement], except for all those others that have been tried."

Cruise ships are cookie-cutter designs relative to military ships due to...more ships per class (model)? Lack of armament?

They are still made of steel, are welded/riveted together in modules, and must be watertight. Is the knowledge of how to properly weld a hull-section for a commercial ship utterly nontransferable to military work?

One of them is a war machine made by the world's richest country to defeat the war machines of other very rich countries.

The other is a floating hotel.

At the very least the floating hotel can theoretically be built out of several nearly identical sections, since hotel rooms are largely all the same fore to aft. Cargo ships have the same benefit.

That said, most of the cost savings is probably just economies of scale. Civilian fleets are much larger than military fleets.

Does a machine's purpose change how the welding for that machine is done?

Probably because of different alloys used, different thickness. You don't expect a commercial ship to be shot at with missiles.

Yes.

I learned a couple of afternoon's worth of welding (TIG and MIG, with a dash of spot) and looked at some books regarding it. I realized that I was staring into a piece of craft that would take years to actually master the nuances of, if I were even capable of it.

Very much, yes. Yes because of the probably different steels in a cruise ship versus a battleship, yes because of lifetime expectancies, yes because of stresses expected, yes because of inspection schedules. I probably don't have even a good enough sense of what is required to come up with half of where the differences would lie.

Why is building a house cheaper than building a ship?

How many people try shooting at your house?

I completely agree with you (15kt and 22kt are very different, for one thing), but...

"If the mechanical linkage fails, hook a chain to both sides of the rudder and pull in the direction you want!"

How many people does that take? Can you really do it with a crew of 13?

You'd use chain pulleys. I work for a company making (among other things) rudder steering machines, and they are typically engineered to never fail.

As a first-order approximation, that holds true. (In the event of a black-out, there are redundant power supplies and mechanical fallback controls (think big, geared control wheel) - or also hand-crank pumps and hydraulic valves.

It is far more common for the rudder to fall off than for the steering machine to fail catastrophically.

In WWII it wasn't uncommon for rudder assemblies to jam when struck by shells or torpedoes, but that era is long since over.

Given sufficient force, anything fails - but the steering gear is typically fine even after the rudder has fallen off; replace bearings, new rudder stock, new rudder, off you go.

(Or, as the C/E on a vessel I attended once put it - there are two machines on this vessel which CAN NOT FAIL. The steering gear and this one. (As he poured me a coffee from the engine control room Moccamaster...)

Hello PMS 317 support! The reason we checked ALL of those welds is one of the many many reasons why U.S. ships will remain afloat and remain 'in the fight' in time of war while other's won't. Protecting your country isn't always glamorous and often a thankless task.

Also, I'm not saying government program offices are perfect. There are certainly lazy, incompetent, and ignorant people. However, these types of people are in every industry. For the most part, I've worked with several very talented folks who are patriots and vigorous stewards of tax payer dollars (because guess what - we are all tax payers). Not all great talents, but there is a fair amount.

The subject paper isn't worth the handful of photons that scorched my retinas when I read it.