Das Boot or the American Fleet Boat

tater · 03-22-10, 12:29 PM

I read in Friedman that the limiting factor on Fleet Type depth was actually the trim pump (which was based on a German design) seeing as it's not just the hull, but also every penetration that might leak. They made a new type of trim pump in 1944, and were much better off. I think the actual crush depth was beyond 675 feet.

It's tough, as I don't think either side destructively tested real boats, it was all sort of theoretical, whereas in practice, skippers on both sides went well below "sanctioned" depths.

You also have to be careful with production stats vs wartime use. US battery specific gravities were changed from the peacetime value upwards, increasing storage capacity, for example. So the time at 2 kts in the manual would be wrong if based on the lower sg. I'm sure there is loads of that on both sides.

03-22-10, 12:29 PM	#23
tater Navy Seal Join Date: Mar 2007 Location: New Mexico, USA Posts: 9,023 Downloads: 8 Uploads: 2	I read in Friedman that the limiting factor on Fleet Type depth was actually the trim pump (which was based on a German design) seeing as it's not just the hull, but also every penetration that might leak. They made a new type of trim pump in 1944, and were much better off. I think the actual crush depth was beyond 675 feet. It's tough, as I don't think either side destructively tested real boats, it was all sort of theoretical, whereas in practice, skippers on both sides went well below "sanctioned" depths. You also have to be careful with production stats vs wartime use. US battery specific gravities were changed from the peacetime value upwards, increasing storage capacity, for example. So the time at 2 kts in the manual would be wrong if based on the lower sg. I'm sure there is loads of that on both sides.