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Comment Re:wrong premise (Score 1) 200

White: 19,809
Black: 628
Asian: 9,924
Hispanic: 1,428
Hawaiian/Pacific: 61
American Indian: 41

You see, this is the funny bit. If you wanted to make it representative of the general population, you'd need to hire about 5,000 MORE whites and fire about 8,000 asians. But of course, facts are wildly unpopular when people just want to play identity politics and hate on the majority.

Comment Author living on another planet? (Score 1) 726

Did the person who wrote TFA even look for consistency in their article? Who the fuck says you need to build your own? There are tons of options for buying pre-built gaming PCs, so getting into PCs is no more difficult than knowing how to order shit online. And did he just seriously mention gaming and Apple computers in the same paragraph? Just casually browsing newegg I managed to configure a custom pre-built PC in 5 minutes that would absolutely skull fuck anything currently sold by Apple at twice the price in gaming performance.

Comment Re:Sun alumnis (Score 1) 43

The question is: will Samsung integrate those pearls? Or would this Solaris platform be shelved?

Shelving the Illumos core of SmartOS (Joyent's cloud OS platform) would essentially completely destroy all value in Joyent. Its distinctive cloud technology is intimately tied to Zones.

Comment Re:drone vs autopilot (Score 1) 59

The FMS doesn't navigate, it assists pilots in navigating. Yeah, it's cute while flying on the pretty magenta line, but if you've ever flown in real life, you'd know that things rarely go exactly according to plan each time. Diversions, directs, holdings, offsets, vectors, changes in approaches, go-arounds, terrain avoidance, all ultimately end up as decisions by pilots. The FMS is a helpful automation tool, but it's a tool for the pilots. It is in no sense autonomous.
And give me a break on "handle emergencies". The best I've ever seen an FMS do is give you an engine-out SID or max cruise performance adjustment. It won't fly the aircraft for you, it won't solve the problem for you and ultimately it won't decide for you. It is a means, not an end.

Comment Re:drone vs autopilot (Score 1) 59

An autopilot is a relatively straightforward and simple system. It has a small handful of fixed modes and is programmed, adjusted and continuously monitored by a human pilot in flight. If an autopilot starts messing things up (and this happens more often than you'd think), the human pilot takes over and stabilizes things. If an emergency occurs, the human takes over. If a helicopter loses its engine, the pilot judges a safe landing spot and executes an autorotation landing. An autonomous drone is way past these. Besides doing the whole flight without human intervention or oversight, it needs to be able to make decisions when shit starts hitting the fan.

Comment Re:My father flies for Copper Valley Air in AK (Score 1) 216

Unfortunately for section (b)(1) to apply, section (b)(2) has to apply as well (that's why there's an "and" at the end of (b)(1)). Primarily, section (b) is meant for people like traveling salesmen, so that they can fly themselves and possibly their colleagues, but not receive compensation for the carriage of people or cargo, i.e. the flying mustn't be their primary job description. Also, the FAA regs do not care one bit about whether you're working for the USPS (directly or indirectly), employment/contracting details or anything other than whether money has changed hands. Anyway, I wouldn't be surprised if the USPS has some special exemptions in the laws explicitly allowing it to circumvent PPL limitations. Wouldn't be the first time the government put in exceptions to the rules for itself.

Comment Re:Idiotic troll in the summary... (Score 1) 286

If you want to go full-retard, why don't we talk about the amount of energy we can get from nuclear reactions of Lithium atoms versus carbon atoms? It's just as relevant as this spewing crap.

Gee I hope you're not doing nuclear reactions in your fuel cell.

Compared to advanced piston engine airliners of the 1950s, current jet airliners are only marginally more efficient per passenger-mile.

Yes. But the pistons were also a lot slower, noisier, less comfortable and less reliable, all of which are rather important details to airlines.

At lower-speeds, props are much more efficient than turbofans, and props can of course be easily driven by electric motors.

And you know what's most efficient? Not going anywhere. If there's a flight that takes 4 hours and another that takes 8 hours, I'll strongly consider the 4 hour one, even if it costs more. Moreover, the airline sees it like this: how many passenger-miles can I do with this type per year? That equates directly to profit. Slower airplane = fewer seats sold per year = lower profit margin. Even if your shiny new airplane is twice as efficient, if it's half as slow, you've not actually gained anything. Why do you think airlines buy jets for anything above regional?

At lower-speeds, props are much more efficient than turbofans, and props can of course be easily driven by electric motors.

You can also drive a fan using an electric motor just as well.

And electrically-driven aircraft is incredibly simplified, to the point that airlines would want them for their lower maintenance costs and less downtime, even if the efficiency wasn't substantially better

Well, maybe. It depends on the details. For one thing, the FAA won't let you get away with just one fuel cell system. You're gonna need two independent ones, or else you won't be allowed to put any passengers on it. It's unclear if it's gonna be simpler, require less maintenance or be more reliable, as no such aircraft are even on the serious drawing board (I don't mean concepts, I mean actual detailed designs for flight worthy hardware).

Comment Re:Batteries need similar engines for thrust (Score 1) 286

Actually turbine engines vs electrical motors aren't all that much different in terms of power-to-weight ratio. You can design a ultra-high-bypass turbofan that's electrically driven and suffer no loss of speed. It'll just be a fan and the turbine engine core is replaced with an electric motor. It's the battery weights that kill the idea. ATM far too heavy and too many operational complications to be practical.

Comment Re:Energy density per kg (Score 1) 242

You're forgetting how inefficient turbofan engines are at part-throttle conditions.

Proportions matter here. Turbine engines run in cruise at around 95% of rated RPM and about 3/4 to 4/5 of maximum thrust. In those regions, they are pretty much at the efficiency plateau. Those things aren't designed by idiots.
As for idling, yeah, they're inefficient. Everybody knows this, which is why partial-engine taxis are common nowadays and even so the overhead isn't so bad. I just did a quick calculation with my dispatch tool and a 737-800 on a relatively short hop of ~1.5 hours (only about 1 hour actual air time). A 20 minute taxi-out and 8-minute taxi-in (all engines running) comes to only about 9% of the trip fuel (6000 lbs trip, 500 lbs taxi). Would airlines be happy to reduce it? Definitely. But is it some huge environmental saving? Not really. And keep in mind, this is short-haul, so about as high as it gets. On longer routes the taxi falls quite dramatically. On a transatlantic route it's only about 2% of the trip fuel and transatlantic is quite short by long-haul standards (only ~6 hrs flight time).

Comment Re:not going to work (Score 1) 242

A turboprop is basically a very high bypass turbofan with a lower exhaust velocity. The means its propulsive efficiency is best at lower air speeds. Maximizing propulsive efficiency, in the simplest terms, is simply about using as much of the energy provided by an engine to displace the aircraft forward and as little to displace the surrounding air backward - you want to get the aircraft from point A to point B, not the static air in reverse. Hence, propulsive efficiency is best when effective exhaust velocity is as close to true airspeed as possible. Propeller effective exhaust velocity is lower than for turbofans, so they work better at lower speeds than turbofans do. It actually has relatively little to do with altitude and fairly little to do with how the mechanical power to drive a prop/fan is generated.

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