Re: Campaigns

At 5:40 AM -0700 8/23/01, David Griffin wrote:
>
>Well, you have to be careful as to what you learn
>on the history channel, but according to them, they
>were cheaper, using welding instead of rivets (and
>so were less resilient to storms and easier to sink.
>At one point the shipyards were competing to see
>how fast they could build them. The winner was just
>about 4 days!

Welding is actually stronger and lighter. It just has different crack 
propagation issues. Cracks stopped at riveted seams, but the stress 
could be transferred through the welded seam. There were also issues 
in the metal composition due to issues with manganese imports. The 
metallurgy had been changed to include a higher content of carbon 
which was stronger but more brittle. The once the nature of the crack 
formation was discovered short term fixes (crack arrestors) and 
repairs allowed for the existing ships to be used. This problem of 
high probability of crack formation in ships (especially the #3 cargo 
hatch cover on the Liberty Cargo ships) affected a large number of 
vessels. For example, "On Feb 1, 1946 there were 2212 liberty ships 
in operation, 2,047 had had corner's modified, 1854 had had crack 
arrestors added." (pp 213, Naval Engineering and American Seapower, 
Rr Adm King)

>
>They did basically the same thing in WWII for
>escort carriers. So I suspect the same trick might

And for LSTs, DEs and PT boats.

>be possible in FT. Perhaps it would be possible
>to design a light carrier (4 squadrons) with a
>fragile hull at a very cheap price. Since fighters
>are so effective in FT, it might work out well.
>Fighters, unlike warships traditionally, tended
>to be built on assembly lines. Indeed it was this
>assembly line mentality that resulted in ships
>like the liberty and the escort carriers.

It was prefabrication. Not assembly lines that allowed the liberty 
ships. One allows the other, but they are not the same.

--
- Ryan Montieth Gill		DoD# 0780 (Smug #1) / AMA / SOHC -
- ryan.gill@SPAMturner.com  I speak not for CNN, nor they for me -
- rmgill@SPAMmindspring.com	     www.mindspring.com/~rmgill/ -