3 ms·

Are you sure they make them out of titanium to save weight? I have two anecdotal pieces of evidence: 1. I have a friend who does welding for the navy and was c

Are you sure they make them out of titanium to save weight? I have two anecdotal pieces of evidence: 1. I have a friend who does welding for the navy and was called in to replace part of the hull of a nuclear sub due to a very hilarious design flaw. It was >6" thick and took days to fill in... with steel. 2. I've read "Concepts of Submarine Design" which goes into great detail on the principles and systems of military sub design. The authors make the case that getting more weight is often a problem. This makes sense because every foot or air space needs to be displaced by more weight in the steel of the sub. So if they had a problem with subs weighing too little, they could just make them more spacious. And they're not very spacious.

DickingAround 11y ago
Third anicdote; titanium is pretty expensive stuff. Online metals is selling a 3"x12"x12" piece for $1.7k. If your hull was 200' long, 15' in diameter you'd need $486M just for the raw titanium on the hull. That seems high just for the hull, even for a nuclear sub. Google is saying the whole thing is probably about $2B and I'd expect all the other stuff in there to cost a lot.
- paulmd 11y ago
  A naval yard is not paying small-lot retail prices for their materials.
- restalis 11y ago
  The supply has something to do with the price and the USSR had no shortage of titanium, so the accounting in your example would have been valid only for one side of the iron curtain.
gnarbarian 11y ago
What was the design flaw?
paulmd 11y ago
Making a sub bigger increases drag, particularly if you are making the frontal profile bigger.