...Paul Allen and submarines, I've read somewhere he intensd to order one of these.



I bet not.

After looking over the description and specifications, I'm thinking this thing looks pretty bogus.

There is no way they can cut a bunch of seven foot diameter holes in a 26' diameter pressure hull, fill those holes with plastic windows, and then take the thing down to it's rated operational depth of 1000 feet. At least, not with any expectation of ever bringing it back to the surface! Anybody know how many PSI water pressure would be on those windows at 1000 feet? Each window would have 5541 square inches...

The electric motor specs are a bit suspect as well.

We're looking at a total of 3280 KWH of electrical storage, but assuming that these are lead-acid batteries (and I don't know of any other technology suitable for such a large-scale application) at best you will only be able to use two-thirds of that capacity without risking irreparable harm to the batteries. So call it 2150 KWHs available. The motors themselves have a maximum output of 740 KW, that's almost exactly 1000 HP.

They're claiming a maximum submerged speed of 10 knots, which I assume would require all 740 KW. They claim a six hour endurance at that rate, which would require 4440 KWH, more than double the amount of onboard capacity availabale.

Further, they claim a 140 hour submerged endurance at 2.5 knots. To get 140 hours from 2150 KWHs would be a continuous draw of about 15 kilowatts, or about 20 horsepower. I would be very surprised if 20 HP would propel a 213 foot long 26 foot diameter craft with all the protrusions shown for bridge acoutrements etc. at a speed of 2.5 knots -- while submerged! In fact, I'd be surprised if basic life support (lighting, heating, air circulation, cooking, oxygen generation) could be done on 15 kilowatts, leaving nothing left for propulsion.

There is also a discrepancy in maximum claimed speeds submerged vs surfaced. On the surface they are claiming 16 knots, from two 1100 horsepower diesels. Submerged they are claiming 10 knots from 1000 horsepower. Just guessing here, but my gut feeling is that total drag submerged would be about two times the drag experienced on the surface. It's been a while since I knew these things for sure... but I think power required for the same speed goes up as the cube of the drag (double the drag requires 8 times the power for the same speed.) So if that is right, and 16 knots on the surface requires 2200 horsepower, that same speed submerged would require more than 17,000 horsepower. It doesn't seem reasonable that if it could theoretically go 16 knots submerged with 17,000 horsepower, that it could go 10 knots (60% of that speed) on just 6% of that power.

I've decided that I'm not going to send them my $78.000,000 unless they can answer these discrepancies. Of course, the real deal breaker might be if I demand they install an empeg at no additional charge.

tanstaafl.








"There Ain't No Such Thing As A Free Lunch"