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Personal Submarine Cruises SF Bay
LandSonar writes "Graham Hawkes, the guru of the submarine design business, tried out his new submersible sea plane yesterday in SF Bay. Called the 'Deep Flight Aviator'. Article and cool pictures. This craft doesn't use ballast like traditional subs. Flys more like a plane. 'It looks like something NASA might build or the Blue Angels might fly.'"
I was a little disappointed to see that the term "fly" seems to describe how it moves through the water, rather indicate the capabilities of a submersible flying boat... Now that would be cool!
When I'm in a submarine, I don't want anything exciting to happen.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
Bernoulli's principle still applies, in fact, water behaves alot like air, except that it's more dense. you have to have the right airfoil shape thought
A cheap, small, personal submarine, capable of carring two people--or one person and 200lbs of drugs from Mexico or Canada into the U.S.A. (or 200lbs of explosive, or ...)
Watch the U.S. Coast Guard build lots of sonar installations. Watch the ecologists sue the Coast Guard for what all that sonar does to the sea life.
Watch Congress outlaw personal submarines.
*IANAEngineer*
As I understand it, The Bends occur when the body of a diver is subject to the pressures exterted by water at depths. Breathing air is regulated by SCUBA gear such that the pressure increases to offset water pressure on the lungs. This increases the pressure of nitrogen gas in the blood, which expands when the pressure is released.
I have a feeling The Bends would not be a problem in a submersible, depending on one condition - internal air pressure is not raised to reduce pressure stress on the hull. At any great depth, water pressure is so great as to make the benefit of any reasonable air pressure increase negligable.
I think that the hull would simply be made strong enough to withstand the water pressure with internal air pressure remaining at sea level air pressure or thereabouts. In this case, the human body would not be subjected to pressure increases/decreases as the sub dives and ascends.
IIRC, military submarines do not change internal pressure when changing depth. Therefore the Bends are not the limiting factor of dive rate - what limits the rate for military subs is that the steel pressure hull cannot withstand rapid pressure changes without contorting dangerously.
If someone made a deep-sea diving sub with a pressure hull made of a material very resistant to rapid change in pressure, there would be no theoretical limit to dive rate, even with a human inside. *As long as the hull is strong enough to allow constant internal pressure*
I may be very very wrong, but this is my observation.
What's happening is that when a comment moderation is reported to you (and also immediately after you submit a comment) the moderation total will reflect the +1 score that you get for being logged in, but the +1 (for a total of +2) karma bonus doesn't show up.
The moderation tallies are actually correct when you look at the lists of comments--you get the bonuses to which you're entitled. If you check your user profile, the correct values are reported there as well. So the system isn't really 'horribly broken', it's just a bit flaky. Someone will fix it eventually. In the meantime, you're not just here for the karma, are you? You just want to contribute in a positive way to the discussion, so don't sweat the totals.
I've noticed this as well. Perhaps the ol' Slashcode isn't up to snuff anymore? Or maybe the number of users is starting to put a strain on the system. I don't have to make multiple retries; I find that waiting a minute for the submission to go through works. If it's not worth waiting a minute to say, it's not worth saying, right?
Aside: I know this is offtopic. I am posting without karma bonus so I'm a smaller target for moderators. ;)
~Idarubicin