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Comment Re:What are they up to? (Score 5, Informative) 73

Coaxial helicopters still have a tail due to the controls on the empennage. Helicopters are a bit odd in that the pilot is basically flying the rotor disk, and the fuselage is kinda just "along for the ride". So, if you wanted to rotate or adjust the pitch of the fuselage, you'd need some sort of controls on the fuselage to do so. (Some adjustment can be made with the rotors, but the standard tail controls are a bit simpler.) So, while coaxial helicopters are more inherently stable and don't need a tail rotor, they'll still have a tail. (See the Ka-50, X2 and Ka-27 among others, as examples.)

The reason you want controls at the aft end of the the tail is because for things like the elevator, you want as big a moment arm as possible to reduce the force required to adjust the pitch of the aircraft. Similarly, the vertical stabilizers are there to help reduce sideslip at higher speed, since a helicopter can fly in any direction, regardless of the orientation of the fuselage. (Generally for lighter helicopters, the vertical stabilizers are fixed, though the larger ones can have a movable rudder.)

Additionally, having a tail will help you if you need to do an autorotation, as it will help prevent the rotors from impacting the ground at the rear when you flare it right before landing. (Here are some examples:

Disclaimer: While I'm a helicopter engineer, I don't work on the controls, so this may be a bit of a simplistic explanation. :)

Comment And the free market always finds a way... (Score 4, Interesting) 473

You can already get around the restrictions if you want an old fashioned light bulb, they're just called Heatballs instead. Two guys in Germany started marketing them as "heaters that fit into a light socket" last year after a similar law went through in the EU.

Comment Re:Easiest new tech for football: RFID in balls (Score 1) 257

A system like this was proposed for the 2006 World Cup, but Adidas and FIFA opted not to use it because they found some issues with it. I also heard somewhere that a few teams tried it in a few exhibition games (not sure if it was this same system), and the fans didn't like it because they couldn't argue with one another about whether someone actually scored or not! And since pro sports is just entertainment, you certainly don't want to alienate your fan base...

Minnesota Introduces World's First Carbon Tariff 303

hollywoodb writes "The first carbon tax to reduce the greenhouse gases from imports comes not between two nations, but between two states. Minnesota has passed a measure to stop carbon at its border with North Dakota. To encourage the switch to clean, renewable energy, Minnesota plans to add a carbon fee of between $4 and $34 per ton of carbon dioxide emissions to the cost of coal-fired electricity, to begin in 2012 ... Minnesota has been generally pushing for cleaner power within its borders, but the utility companies that operate in MN have, over the past decades, sited a lot of coal power plants on the relatively cheap and open land of North Dakota, which is preparing a legal battle against Minnesota over the tariff."

Living In Tokyo's Capsule Hotels 269

afabbro writes "Capsule Hotel Shinjuku 510 once offered a night’s refuge to salarymen who had missed the last train home. Now with Japan enduring its worst recession since World War II, it is becoming an affordable option for people with nowhere else to go. The Hotel 510’s capsules are only 6 1/2 feet long by 5 feet wide. Guests must keep possessions, like shirts and shaving cream, in lockers outside of the capsules. Atsushi Nakanishi, jobless since Christmas says, 'It’s just a place to crawl into and sleep. You get used to it.'”

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