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Comment Re:redundant aircraft (Score 2) 103

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).

Submission + - What site would you recommend to replace Slashdot? 1

koreanbabykilla writes: Now that it looks like I'm no longer going to be able to use Slashdot due to beta.slashdot.org, I need somewhere to kill a few hours a day at work. Any suggestions?

Submission + - Kim Jong Un, Ghost of Hitler, Announce Approval of Slashdot Beta

An anonymous reader writes: The Supreme Leader of the Democratic People's Republic of Korea and the ghost of the former leader of National Socialist German Workers' Party have approved of the new Slashdot Beta site in a rare instance of agreement amongst the two. The two strong personalities have a history strong disagreement of the most mundane of things but united today outside the Great Pyongyang Unicorn Lair with Slashdot Editor Samzenpus to show support. "Morale at Dice [Slashdot's parent company] is at an all time low, but the show of support from such great world leaders is an encouragement to the entire team", said Samzenpus.

Submission + - Ask Slashdot: Opinion of slashdot beta? 9

An anonymous reader writes: What are your thoughts about slashdot beta? Post your complaints here so that I don't have to see them elsewhere. Additionally, if the beta is so bad that you don't want to stay, what other news website do you recommend?

Submission + - Slashdot beta sucks 9

An anonymous reader writes: Maybe some of the slashdot team should start listening to its users, most of which hate the new user interface. Thanks for ruining something that wasn't broken.

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: 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. :)

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. 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...

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