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Comment Re:This is such a tree hugger article (Score 1) 496

It's more that today's diesels are especially bad; at least potentially.

The general trend behind this is that people want to reduce CO2 emissions & use less fuel. Now, diesels can be made very efficient, particularly with high pressure combustion.

Trouble is, high pressure combustion gives high temperatures which are certainly more efficient, but boost the levels of NOx. Now NOx is a fairly horrible pollutant; it kills people. But the older, less efficient diesels didn't run so hot/at such high pressure, and didn't produce much of it, but produced particulates and higher CO2.

Now, some cars can do both; not produce much NOx and produce less CO2 as well as low particulates; but the way they normally do that is with urea injection which acts as a catalyst.

For various reasons VW wanted to avoid the catalyst tank, and yet also produce less CO2, but their (expensive) attempt to make an engine that did this using exhaust recirculation failed; and then they faked the tests.

So yeah, basically diesels tend to make worse NOx now.

Comment Re:Cars (Score 1) 496

It's not true that cars are inherently bad for your health. Electric cars don't have to burn anything; you can run them off wind, hydroelectricity, nuclear, solar; no particulates.

And they don't take such a lot of electricity either; only 10kWh per day to do the average 30 mile range, easily made with solar panels or wind turbines.

Sure, there may well be some particulates produced in their manufacture, but as the grid becomes greener, even that may become less; steel can be made from recycled metal using arc furnaces for example.

Comment Re:make it user-selectable (Score 1) 235

That's what I think too. The manufacturers will write code that will keep THEM out of trouble with the local legal system. In most cases it will avoid killing the driver as well, but there's no way that they're going to make the car software swerve off the road and mow down a queue at a bus stop to preserve the life of the driver.

People are saying: it's an ethical issue, no, it's primarily a legal issue, the programmers/company execs will keep themselves out of prison, everything else is secondary.

Comment Re: Sakura Battery (Score 1) 209

Not so much. Mainly, Teslas can charge fast, just because they have an enormous battery; so it can handle proportionately more power, and it turns out that having a big (heavy) battery doesn't affect the energy efficiency that much, so they can get lots of range as well.

Main downside: $$$$

That's also why Teslas accelerate so fast: the battery can output proportionately more power and Tesla can fit huge motors. If you put the same motor in a Nissan Leaf, the battery would explode- it can't safely supply the juice.

Of course the bigger battery makes the car heavier, which slows it down a bit, but adding battery is still a net win.

Cooling is also important, and smaller batteries DO help, but a lot of it is just having the massive battery pack.

Comment Re:Typical of those poorly trained... (Score 1) 226

Maybe it's related to the AF crash. In that, they pulled back on the stick and the stall warning went away. They pushed forward, and the stall warning came back.

Apparently, the stall warning system didn't believe the angle of attack readings (which were unusually high, but basically accurate) and that automatically silenced the alarm, even though: stall.

Comment Re:Typical of those poorly trained... (Score 1) 226

> But there's something weird going on here. The first officer apparently pulled his stick all the way back and made the plane climb at a rate of more than 10,000 ft/min before it stalled. That's a pretty insane maneuver and I can't find a rational explanation for it no matter what his training was. It's not an "inappropriate response" but rather a completely unprovoked action for no good reason whatsoever.

Maybe it would make sense if everything was working properly.

With modern fly-by-wire, you're not flying the aircraft, you're telling it what needs to be done. Pulling back all the way on the stick means 'go up, as fast as possible', and the aircraft will go up as fast as it can, and it won't let it stall.

In a degraded mode what will it do?

At that point a lot of the fly-by-wire will have shut down; and it may well let you stall it (looks like it does, two aircraft have been lost that way.)

So maybe the aeronautics have been implicitly training the crew to use over-the-top stick inputs, and that leads to crashes in these kinds of situations.

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