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Comment Re:If there was a criteria for safe unlocking (Score 1) 83

but this sandwich very likely isn't as expensive as you think, unless the plane is truly purely mechanical (unlikely).

As a former Scaled engineer, I can tell you, the plane is almost purely mechanical. SS1 was completely mechanical, except for an electric trim mechanism for the horizontal stabilizer. SS2 was identical, except the horizontal stabilizer was boosted by a self-contained electromechanical system that took a long time to design with failure modes that were controllable. That means pushrods and cables/pulleys to the control surfaces, large springs for gear extension, and mechanical actuators for the feather and feather locks. Aside from the avionics, one of the few electrical flight controls was the switch to arm and ignite the rocket.

Comment Re:A "safety feature" (Score 1) 83

They do have precise procedures about this. Its called the flight test card. The test pilot flies the procedures exactly as they are written on the card. They do nothing else unless some other anomaly during the flight requires them to fall back to basic flight training and just fly the airplane. They brief to that card before the test flight. The practice and train to that card on the simulator. If you know that the cockpit environment is going to be busy, you train your muscle memory to follow that card even if you can't look at it to check off each step.

We've all had things we've done a hundred times in a row, and for no particular reason, that one time, we forgot a step. Mike's muscle memory may have failed him this time and he ended up doing a procedure on the card out of order.

Comment Re:I don't believe it. (Score 1) 83

Like every test pilot at Scaled, Mike was a competent engineer in his own right, in addition to being a test pilot. I guarantee that everyone knew that if the loads were high enough the feather would move if it was unlocked, including the pilots. Like I said in another comment, I also guarantee that Mike flew the procedures on that test card plenty of times on the simulator and threw the feather unlock at the Mach 1.4 callout correctly every time. But in a high workload environment, no matter how much training you go through, sometimes the muscle memory that you're trying to train can fail you and you end up doing steps out of order.

You can't design out *all* the failure modes. If you try to, you end up with computer flying the plane and you still end up with some failure modes you can't work around. You can argue that's why spacecraft shouldn't be human piloted, but in this case, there were pilots there for a reason. Developing all that software for the computers takes time and money to write and to design out those failure modes. Scaled is good at flying experimental planes, and good at training pilots to do so. They applied that experience to spacecraft pretty successfully over the course of 17 flights for SpaceShipOne and 54 flights for SpaceShipTwo and did so much more quickly and cheaper than it would have been done if it were all controlled by computers.

Comment Re:What the NTSB actually said (Score 1) 83

As a friend of Mike, a former Scaled Engineer, and one that was directly involved in a previous Scaled accident, I have to completely disagree with your statements.

The culture at Scaled has been and will continue to be focused on nothing but safety. This was the first flight accident that Scaled ever had in its existence since 1982, with dozens of first flights of new aircraft designs and hundreds of follow up test flights. There had been engineering mistakes on many flights previously (I certainly made some), but the safety culture that Burt Rutan instilled in everyone focusing on "Question, Never Defend" was prevalent and always managed to get the aircraft home. The report mentions that no one ever thought about what would happen if a pilot pulled the unlock lever early. I guarantee you, everyone did. But just like a pilot knows not to put the gear down above max gear speed, or do full control movements when faster than the max maneuvering speed because things will break (and there are no interlocks on those things either), it could easily be expected that a pilot would never throw the feather unlock except when they are supposed to. Test pilots fly the test card and nothing but the test card. They are highly trained to follow the procedure on the test card. I'm certain Mike did that card over and over on the simulator and threw the feather unlock at the Mach 1.4 callout correctly every time. For some reason he uncharacteristically did the steps out of order on this flight. The result was catastrophic.

Your analogies don't hold up. If I'm in a car at 60mph and I turn a little too early, directly into a tree instead of on to a highway exit ramp, it can be pretty catastrophic to the car and its occupants. Until our autonomous cars show up, you can't design out the steering wheel. If you don't have time to look at the checklist for your next step because of the environment or because the workload is high and your muscle memory fails and you end up doing steps a little too early, it might also be catastrophic. If the procedure or checklist isn't followed exactly, catastrophic things can happen even on highly automated airlines.

Similarly, since a car's crumple zone, seat belt or airbag probably won't save an occupant that crashes into a tree at 200mph (lets up the speed since Mach 1+ is quite a bit higher than most average planes), you can probably understand that at certain speeds, you can't design in similar safety systems. This is called tradeoff analysis and is part of engineering, not malpractice.


Controlling GNOME 3 With Skeltrack 18

dartttt writes with an excerpt from Ubuntu Vibes: "Skeltrack is a Free Software (GPL3) library by Igalia for tracking the human skeleton joints from depth images. It is implemented with GLib and uses plain mathematics to detect the human skeleton and although it does not use any database, it was inspired by Andreas Baak's paper: "A Data-Driven Approach for Real-Time Full Body Pose Reconstruction from a Depth Camera" Skeltrack devs have recorded very cool videos showing Gnome Shell and Linux games being controlled through gestures."

Big Dipper "Star" Actually a Sextuplet System 88

Theosis sends word that an astronomer at the University of Rochester and his colleagues have made the surprise discovery that Alcor, one of the brightest stars in the Big Dipper, is actually two stars; and it is apparently gravitationally bound to the four-star Mizar system, making the whole group a sextuplet. This would make the Mizar-Alcor sextuplet the second-nearest such system known. The discovery is especially surprising because Alcor is one of the most studied stars in the sky. The Mizar-Alcor system has been involved in many "firsts" in the history of astronomy: "Benedetto Castelli, Galileo's protege and collaborator, first observed with a telescope that Mizar was not a single star in 1617, and Galileo observed it a week after hearing about this from Castelli, and noted it in his notebooks... Those two stars, called Mizar A and Mizar B, together with Alcor, in 1857 became the first binary stars ever photographed through a telescope. In 1890, Mizar A was discovered to itself be a binary, being the first binary to be discovered using spectroscopy. In 1908, spectroscopy revealed that Mizar B was also a pair of stars, making the group the first-known quintuple star system."
The Almighty Buck

Economic Crisis Will Eliminate Open Source 753

An anonymous reader writes "The economic crisis will ultimately eliminate open source projects and the 'Web 2.0 free economy,' says Andrew Keen, author of The Cult of the Amateur. Along with the economic downturn and record job loss, he says, we will see the elimination of projects including Wikipedia, CNN's iReport, and much of the blogosphere. Instead of users offering their services 'for free,' he says, we're about to see a 'sharp cultural shift in our attitude toward the economic value of our labor' and a rise of online media businesses that reward their contributors with cash. Companies that will survive, he says, include Hulu, iTunes, and Mahalo. 'The hungry and cold unemployed masses aren't going to continue giving away their intellectual labor on the Internet in the speculative hope that they might get some "back end" revenue,' says Keen."

Dead Goldfish Offered The Vote In Illinois 216

Election officials in northern Chicago want to know why voter registration material was sent to Princess, a dead goldfish. "I am just stunned at the level of people compromising the integrity of the voting process," said Lake County Clerk Willard Helander, a Republican, who said she has spotted problems with nearly 1,000 voter registrations this year. Beth Nudelman, who owned Princess, said the fish may have got on a mailing list because the family once filled in her name when they got a second phone line for a computer. When will we recognize a goldfish's right to vote?

Comment Re:SpaceDev, the engine designer will reuse the te (Score 2, Informative) 282

I know this because I work at Scaled, but if you read all of the info on the Scaled website about SpaceShipOne, you'll know that SpaceDev only provides a small portion of the rocket to us. The rocket is actually a Scaled design with assistance given to us by SpaceDev on the bulkhead between the nitrous tank and the solid rocket and a lot the hardware and valves. We also manufacture the rocket casings, using a nozzle made by a supplier, and send them to SpaceDev to mold the solid fuel in place.

Wait till you see some of our future projects which could put a 200lb satelite into orbit for until $750k.

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