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Spider-Like Catamaran Travels 5,000 Miles On One Tank
Lucas123 writes "Proteus, a Wave Adaptive Modular Vessel that looks like a spider, is so fuel efficient that it can travel 5,000 miles on one load of diesel fuel. The 100-foot-long, 50-foot-wide boat rides on metal and fabric pontoons that have hinges and shock absorbers to flex with the motion of the waves, which helps it to skim over the water at a max speed of 30 knots. It made its debut yesterday in New York harbor."
http://www.wam-v.com/
with some stats:
http://www.wam-v.com/characteristics.htm
still didn't see tank size though...
@AlexSheive
According to http://en.wikipedia.org/wiki/Proteus_(WAM-V) a "load" for this boat is 2,000 gallons.
http://en.wikipedia.org/wiki/Proteus_(WAM-V)
"Her outriggers store the 2,000 gallons of fuel that power the two Cummins Marine Diesel Quantum Series QSB5.9 355 horsepower engines at their sterns."
Actually, according to the link yo provided, the fuel tank is 2,000 gallons.
Remember this relatively recent slashdot article? I couldn't find the article quick enough but I did find the article it was about. http://www.topgear.com/content/news/stories/1832/ Yup, that would be the fabulous electric car that is so LIGHTWEIGHT that it's not classified as a car anymore.
And no, I didn't catch the answer to your question, I just love watching that car crumple in such amazing ways.
My grandfather was a stevedore (longshoreman) and I actually phoned and asked him. He said smaller coastal ships could go about 2,000 to 2,500 nautical miles, while larger cargo and container ships could go 5,000 NM or more, depending on how much fuel they took on. Obviously, transatlantic container and cargo ships have to hold enough fuel to get themselves across the Atlantic.
These "feel good" kind of stories are really annoying, because they leave out so many details that most people end up with a completely skewed perception of the facts.
I did a quick search to get an idea if 2.5 MPG was good for a boat. Here's an article that tested the fuel efficiency of some standard boats - ie boats with normal hulls that sit down in the water, with regular screw propeller propulsion. So they should be pretty poor compared to many other style hulls, etc.
One particular boat has a V8 350 cubic inch engine that can do 51 MPH. So that's pretty fast. At that speed the boat gets 2.4 MPG, which is basically the same as the boat in the story. At a slower speed of 26.9 MPH it gets 3.6 MPG, which is almost 50% better than the "spider boat". Now obviously the range of these boats are vastly reduced - it's like rocketry, where the more fuel you carry to gain distance, the more weight you have to haul, so the actual gain in distance is only small (or perhaps even negative). So these boats can't begin to touch 5000 miles on one tank.
So perhaps the significance of this story is ratio of the range to fuel efficiency? If so, it would have been nice if the author would have simply said that.
Dan East
Better known as 318230.
A mid-range recreational yacht (Say, $60k and 28 feet) will get anywhere from 0.5 - 4mpg. Usually towards the lower end of that scale.. considering the size and speed of that catamaran, it's really not too bad.
My trawler yacht has a 130 ton displacement with a 24 litre diesel engine .
At 1000 rpm (cruising) it does 9 knots which gives it 12000 miles range on
10,000 US gallon tanks or 1.23 gallons per mile. However my payload is 10 people
and 25 tons of equipment.
Boats typically have rotten fuel efficiency compared to cars. You're lucky to get 2 gallons/mile out of most of them.
Understanding the scope of the problem is the first step on the path to true panic.
Most people refuel in Bermuda and the Canary islands when sailing across the Atlantic. That's pretty close to the middle of the ocean. Nuclear powered aircraft carriers go 20 years on a fillup.
moox. for a new generation.
Personal safety in a crash is only related to total energy dissipated in that total energy dissipated places a hard cap on total energy dissipated through you. Vehicle safety design is centered entirely around dissipating as much energy through all parts of the vehicle except the passengers as possible. Greater vehicle weight is only an automatic lose if you're strapped to the exterior of the vehicle at the impact point.
A better example that illustrates the above principle in a more intuitive manner is running into a rock face at 25mph strapped into the driver's seat of a hummer vs hitting that same rock face at 25mph strapped into a pair of Nike shoes. Total energy dissipated in the first case more than an order of magnitude greater than the second, yet the first is going to be much safer than the second because less energy will actually be dissipated through the passenger.
Lighter cars can actually be far more dangerous in a head-on—even with other light cars—than two heavy vehicles. The problem is that very light vehicles simply do not generate sufficient forces to crumple the frame of the vehicle unless the frame is deliberately weakened to allow for this to happen. This presents a serious safety dilemma with very light vehicles, as crumpling the frame is one of the best ways to minimize forces exerted on passengers in a crash. Optimize for head-ons with other light vehicles (much weaker/easily crumpled frame) and you will be absolutely destroyed in a collision with a heavier car. Optimize for collisions with heavier vehicles (stronger frame) and you will be more likely to die in collisions with other light vehicles as the frame fails to crumple and your internal organs nearly explode out the front of your body due to the massive deceleration.
The further the weights of the vehicles involved in a head-on diverge, the greater the degree to which someone will be subjected to one of the undesirable scenarios above. Unfortunately for light vehicle enthusiasts, all other things being equal, the guy in the lighter vehicle always gets the shorter end of the stick. An otherwise walk-away accident may have been made lethal because one guy was driving an F350 rather than a light pickup, but it's the guy in the Geo Metro who dies.
You're looking at the classical prisoner's dilemma here. Do you raise overall safety by driving the lightest vehicle that meets your needs, or do you make the roads more dangerous but maximize your personal safety by driving a massive SUV?
All types of accidents considered, light vehicles may be safer overall but they're definitely not safer for anyone except the people in the other vehicle when you're looking at a head-on.
Except that ton-miles per gallon is a better indicator of fuel efficiency.
Approximate fuel consumption numbers are (from various sources):
Inland Waterways: approx 500 ton-miles/gallon
Rail: 70-200 ton-miles/gallon
Interstate Trucking: 40-100 ton-miles/gallon
Airfreight: 5-35 ton-miles/gallon