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  1. Re:redundant aircraft on Radical Dual Tilting Blade Helicopter Design Targets Speeds of Over 270mph · · Score: 2

    There are 3 other entries in this competition: http://en.wikipedia.org/wiki/Future_Vertical_Lift#Competitors, two of which are tiltrotors.

    Bell Helicopter's entry into this competition is more of an incremental upgrade to their V-22 tiltrotor technology: http://bellv280.com/ The Army also wants something smaller than the V-22 (the V280 will end up being probably 1/3 to 1/2 the size) and it will presumably be correspondingly cheaper per aircraft. (Of course with the way these programs usually turn out, who knows how much budget overrun it'll see...)

    Karem Aircraft is also proposing a tiltrotor, and is partnering with Lockheed, though I don't think either has experience with tiltrotors.

    Sikorsky and Boeing teamed up to build an upgraded version of the X2.

    Interestingly, AVX also has a lot of former V-22 engineers and management working for them, so they may have had their reasons for opting against a tiltrotor arrangement, such as a simpler drive and control system.

    Personally though, I'd bet that either the Bell or Sikorsky/Boeing proposal will get selected, simply because they've had experience with comparable aircraft, which will give them a better handle on the estimated performance, rather than just making paper helicopters. They're also the big names in US military rotorcraft, and currently have the facilities to ramp up to that kind of production (4000 helicopters is a helluva lot of aircraft).

  2. Re:What are they up to? on Sagita Displays Hot Air Powered Helicopter · · Score: 5, Informative

    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: http://www.youtube.com/watch?v=T-5ARzqF3R4)

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

  3. And the free market always finds a way... on Edison Would Have Loved New Light Bulb Law, Says His Great-Grandson · · Score: 4, Interesting

    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.

  4. Re:Easiest new tech for football: RFID in balls on NFL: National Football Luddites? · · Score: 1

    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. http://www.rfidjournal.com/article/view/2029/ 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...

  5. Re:Idea for a better source of energy on UCLA Engineers Create Energy-Generating LCD Screen · · Score: 1

    Someone proposed this concept last year, but unfortunately I don't think anyone's actually selling it: http://www.wired.com/gadgetlab/2010/02/cork-mouse-charges-itself/

  6. More Details here... on Aerial Video Footage of New York Taken By RC Plane · · Score: 5, Informative

    According to this earlier article, the police and TSA talked to him, but surprisingly didn't charge him with anything. He said they were "more curious than confrontational."

  7. Re:Alternative, natural energy source solution. on GM Loses Money On Every Volt Built · · Score: 1

    Nope, but there *is* enough for a Christmas Tree. :) http://www.reuters.com/news/video?videoId=72584

  8. Re:NASA sure is going downhill fast... on NASA's Stunning Close-Up Photos of Comet Hartley 2 · · Score: 1

    You're probably just joking around, but there is at least one pretty advanced carbon-epoxy spacecraft, the White Knight. Plus, there have been a couple of new American carbon-epoxy aircraft in production the past few years:

    Bell-Boeing V-22 Osprey
    Boeing 787
    Lockheed Martin F-22 Raptor

  9. Re:Who's idea... on Water Main Break Floods Dallas Data Center · · Score: 1

    the most devastated in just about any natural disaster

    But it would be the most protected area during a tornado, which is the most common natural disaster in North Texas.

  10. Re:No way it was the worst on Battlefield Earth Screenwriter Accepts Razzie · · Score: 1

    Sounds like they took a page straight from The Producers.

  11. Re:A simple plan on Breaking the Squid Barrier · · Score: 1, Insightful

    You could also keep it as a defense for your island fortress against James Bond a la Dr. No! (The novel, not the movie.)

  12. Re:Star Trek on Skydiver To Break Sound Barrier During Free-Fall · · Score: 1

    My first thought was the Mobile Infantry from Starship Troopers (the book not the movie), even though he's jumping from a balloon, and not from orbit.

  13. Re:Octopus & the Goldfish on Aussie Scientists Find Coconut-Carrying Octopus · · Score: 2, Interesting

    There was an incident where an octopus didn't like a light shining on him, and started shorting it out by climbing out of the tank and squirting it with water. I definitely wouldn't be surprised if one figured out how to get a little extra food.

  14. Re:really?? on Great White Sharks Visiting San Francisco · · Score: 1

    Yep, there have been a number of biologists studying great whites for a few decades near the Farallon Islands off the coast of San Francisco. There's even a book, The Devil's Teeth, detailing a shark season with the biologists.

  15. Re:419 Scams on Why a High IQ Doesn't Mean You're Smart · · Score: 1

    A good book about actual millionaires in the US is The Millionaire Next Door. It has some interesting trends (like millionaires are more likely to drive an F150 than a luxury car) and shows that most millionaires get there through hard work, investment, and most importantly, don't spend it on a bunch of crap they don't need. The American dream is still alive and well, but most people aren't willing to put in the time, elbow grease and self-restraint to actually get there.

  16. The Blob! on iRobot Introduces Morphing Blob Robot · · Score: 1

    If it gets much bigger, we'll have to call Steve McQueen for help!

  17. Re:This is so important ... on French Deputies Want Labels On Photo-Altered Models · · Score: 1

    That's one thing that has always bugged me. There's always a big commotion about anorexic models, but they don't consider that they are only a small percentage of population, with only 3% of the population having a binge eating disorder, and roughly two thirds of the population is overweight or obese. Don't get me wrong, anorexia is a serious medical condition and people need to be informed about it, but I think its been way over publicized because of all the celebrity gossip that's going around today, so people think it's more prevalent than it actually is.

  18. Re:Please read up before commenting, on Dell Buying Perot Systems For $3.9 Billion · · Score: 1

    The whole story of Perot's rescue was documented in a book by Ken Follett called "On Wings of Eagles".
    At one point, Perot actually flew in to Tehran pretending to be a courier for a news service so he could actually visit the two guys in jail. Pretty ballsy, and while there might be few executives who would organize a rescue attempt, he's probably the only one willing to do that for their employees.

  19. Re:It's Not About Safety, It's About Macho on Nissan Gives Electric Cars Blade Runner Audio Effect · · Score: 1

    Well, I know I love the smell of ozone in the morning.

  20. Re:Water Safety? on NASA Testing Breakthrough In Water Safety · · Score: 1

    Consuming too much silver can turn your skin blue, kinda like this guy. It's not really harmful, but since most people don't want to look like smurfs, you don't want too much of it in your water.

  21. Re:Obvious bullshit on Chinese Clinic Uses DNA Tests To Predict Kids' Talents · · Score: 1

    There's already a company in Boulder, Colorado that tests kids' DNA for a "sports" gene. Apparently there is some sort of link between the ATCN3 gene and athletic ability (like running speed or endurance). This just looks like they're looking at other genes that have a tenuous association with other abilities. That being said, even an overall sports ability is probably based on more than just that gene, so I don't think any of these types of tests are detailed enough to give much of a good result. There was also an article about Atlas Gene in the NY Times last year.

  22. Re:Will it be a Web2.0 site? on Obama To Launch Website For Tracking Tax Expenditures · · Score: 1

    The sad thing is, there already is a website devoted the sewer rat control efforts in New York City, complete with an interactive map showing general rodent population trends: NYC Rat Information Portal

  23. Re:Not a new model on Bats Inspiring Future Micro Unmanned Aircraft · · Score: 2, Informative

    Yeah, they looked at that in WWII . Apparently it worked a little too well, burning down some buildings at the nearby Army base in addition to the test buildings they set up when some bats decided to roost there instead.

  24. Re:white knight 2 looks too fragile on VASIMR Plasma Thruster To Be Tested Aboard ISS · · Score: 1

    The margin of safety for the majority of commercial aircraft is actually 1.5 in the US. When the military releases the RFP for new aircraft, they'll specify the margins they want, but it's typically 1.5. They'll also sometimes add in requirements for no permanent deformation at 115% of load in key components of the structure. Since this would be the first commercial passenger space plane, I imagine Rutan will be pretty conservative on the margins.