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Comment: Re:I'm all for abolishing the IRS (Score 1) 208

by jcr (#49374655) Attached to: Sign Up At Before Crooks Do It For You

I'm trying to come up with a good argument that taxing production is more easily made progressive than taxing consumption, but now I'm not sure that's right.

That's because it isn't right. If someone's spending a million bucks a year, they get taxed on a million bucks a year. If they're earning a million bucks a year and living like a monk, then the funds they've earned aren't out there competing with yours for goods and services. A miser is an ideal neighbor.


Comment: Re:Still photos (Score 1) 431

by Znork (#49368563) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

Hopefully an autonomous system would be designed so well that no human pilot could think that. See for example NASA's Adaptive Control tech; even if that's made to assist human pilots, the fact that it can actually bring some semblance of control to a plane that has lost function and form in many ways shows what can actually be done.

And as Air France Flight 447 shows, pilots may very well do the completely wrong thing, ignoring every correct procedure intended to prevent disaster.

But the most important, and often overlooked, part of such a system would be that you cannot skimp on the electronics. With an autonomous plane, if there's a problem with frosting over on sensors, you're grounded. There's no 'but the pilot is human so he can fly blind if the autopilot fails'. It has to be 100% reliable, all the time, and with massive enough over-redundancy that the plane would essentially already have to be falling apart into pieces for the overall control systems to fail. That would of course be a significant help to human pilots as well, as it sometimes seems they're being used as an excuse to live with flawed instruments and quality deficiencies in the planes.

Comment: Re:Wrong Focus (Score 4, Informative) 117

by jcr (#49365325) Attached to: SpaceX's New Combustion Technologies

As it happens, back in the '80s I worked at a company (Commonwealth Scientific) that built ion-beam guns based on the Kaufman duoplasmatron, which was the basis of the mercury-vapor thrusters that NASA had developed in the 1960s. The company was trying to make the aperture of the guns as wide as possible, and the difficulties included neutralizing the ion beam on the way out, keeping the plasma inside the gun stable, and keeping the beam density even. Basically, the bigger the gun, the harder it was to make it run steadily. When I was there, they had 8" apertures and were working on scaling them up to 12" apertures.


Comment: Re:Still photos (Score 2) 431

by Znork (#49365201) Attached to: Why the Final Moments Inside a Cockpit Are Heard But Not Seen

Yeah, a better compromise is removing the pilots. If it's possible to build an autonomous car, building a completely automated plane is a simple exercise in comparison. Run it on cargo for a few years, leave an option for remote control, but frankly, between terrorists, suicidal pilots, drunk pilots and pilots doing the completely wrong thing, it's time to look for a more long term solution.

The clearest way into the Universe is through a forest wilderness. -- John Muir