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3 Recent Flights Make Unscheduled Landings, After Disputes Over Knee Room

calidoscope Re:Today's business class is the 70s' economy clas (814 comments)

In 1972, SAN to OAK was $24.50 on PSA with no restrictions. Equivalent fare on Southwest is ~$260, cheaper fares are available but come with restrictions.

about two weeks ago
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3 Recent Flights Make Unscheduled Landings, After Disputes Over Knee Room

calidoscope Re:cram lots of people in a confined space (814 comments)

Hmmm, "Get them out by Friday".

A bit OT, but I was surprised to learn that "Attack of the Giant Hogweed" was mostly based on fact.

about two weeks ago
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Hitachi Developing Reactor That Burns Nuclear Waste

calidoscope Re:Good (200 comments)

Electorate, schmectorate, decisions like this are based on who provides the most campaign donations.

about two weeks ago
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Hitachi Developing Reactor That Burns Nuclear Waste

calidoscope Re:Good (200 comments)

The proposed reactor design sounds a bit like the EBR-II at INEL, formerly the National reactor test site, with the design also referred to as the Integral Fast Reactor. This program got shut down in the 1990's, though stories have been told about people who were sent out to Idaho to shut it down came back as converts to the cause.

about two weeks ago
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Power Grids: The Huge Battery Market You Never Knew Existed

calidoscope Re:Yes, we know that. (245 comments)

With solar power, you get peak power and peak air conditioning load around the same time.

Not quite. Peak demand in California is between 6 to 7PM, peak solar production is approximately 12 noon. Peak load does not drop signficantly until well after sunset.

about two weeks ago
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San Onofre Nuclear Power Plant Dismantling Will Cost $4.4 Billion, Take 20 Years

calidoscope Not surprising (343 comments)

Decommissioning costs are still a lot less than it would cost to build the plant now. Letting the plant cool down for a few years makes the process simpler and safer, though the reactor vessel is going to be a challenge.

about a month and a half ago
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Perlan II Project Aims To Fly a Glider To the Edge of Space

calidoscope Re: 100km (44 comments)

Something on the order of 97% of the atmosphere's mass is below 90,000'. 100km is an arbitrary value for the start of space, as the air at 100km is too thick to orbit and too thin to fly in (except dynamic soaring?). In imperial units, 100,000' seems to be the upper limit for flying and 100 miles is about the lower limit for orbiting.

The Perlan II sounds like it will handle like an unpowered U2 - where the planes ceiling will be defined by the "coffin corner" were the low speed stall (classic stall) approaches the high speed stall (Mach tuck from transonic airflow). Perhaps they will be using a more refined airfoil than the U2 to increase the Mach number for high speed stall.

IIRC, the pre-Perlan I sailplane altitude record of approx 47,000 feet was set sometime in the 1960's, surprising it took that long for someone to break that.

about a month and a half ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

I first heard about use of series capacitors in an electric power systems class, 1H 1975, so they have been around for quite a while. It would seem to me that the caps should be able to withstand the DC potential set up by a Carrington event.

about 2 months ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

Any component for a high voltage transmission line is going to be gigantic. Google term "power transmission line series capacitors" should get you started.

about 2 months ago
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The Truth About Solar Storms

calidoscope Re:The failure mode is transformer core saturation (91 comments)

An alternative way of minimizing the effects of a severe solar storm on the grid would be placing series capacitors on the long AC transmission lines. This is done already to increase power transfer capacity of some lines.

Since the solar flare is visible many hours before CME hits, the utilities should have time to configure the grid for the storm. The oerative word here is "should".

about 2 months ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

calidoscope Re:Is that a lot? (190 comments)

Not that much. A typical Tc99m scan involves injection a bit over a billion (10E9) bq per person, albeit half life is only 6 hours. Reminds me of a "warning sticker" for a CB radio - "Danger 5,000 milliwatts".

about 2 months ago
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Rocket Scientist Designs "Flare" Pot That Cooks Food 40% Faster

calidoscope Re:Wow. (204 comments)

I agree wholeheartedly that the pot is more similar to the Jetboil in principle than different. There is a difference in details in that the Jetboil is designed for lighter weight and better heat transfer efficiency than the pot at the expense of a more fragile design.

about 2 months ago
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Today In Year-based Computer Errors: Draft Notices Sent To Men Born In the 1800s

calidoscope Re:dmv (205 comments)

I don't there is anyone in the US who was born in 1897 or earlier.

about 2 months ago
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New Chemical Process Could Make Ammonia a Practical Car Fuel

calidoscope Mid 1960's Army research (380 comments)

There was an article or two in the likes of Mechanix Illustrated or related magazine about the US Army experimenting with ammonia fueled engines. Reports indiacted that engines would function, but had not been developed to the point of practicality. Shudder to think what kind of NOx levels are present in the exhaust.

about 3 months ago
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Scientists Measure Magnetic Interaction Between Two Bound Electrons

calidoscope Newton's ???? inverse cube law (26 comments)

I remember Newton's inverse square law, but magnetic dipoles were more than two centuries after his time.

about 3 months ago
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Astronomers Solve Puzzle of Mysterious Streaks In Radio Images of the Sky

calidoscope Re:Cyclotron Radiation? (66 comments)

That sounds like a reasonable guess as to what is going on. The hot plasma is conductive and the Johnson noise may produce enough current to emit detectable radiation. My recollection was that the sky noise temp at 50 MHz was on the order of 3,000K, and the plasma from the meteor trail is likely to be considerably hotter than that.

about 3 months ago
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The Major Theoretical Blunders That Held Back Progress In Modern Astronomy

calidoscope Error in first example (129 comments)

TFA had the 200 inch Hale telescope on a fictional geogrphical location, Mt. Palomar. The real name is Palomar Mountain. A minor detail, and very common error, but it is the same kind of error the author was complaining about.

about 4 months ago
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New Semiconductor Could Improve Vehicle Fuel Economy By 10 Percent

calidoscope Re:Fuel economy? (119 comments)

The benefits in the modest increase in efficiency are not so much from reduced energy usage, but the higher efficiency reduces the amount of waste heat that has to be removed from the PCU. The higher junction temperatures allowable with SiC makes the cooling task even easier. What has Toyota excited is that the PCU with SiC is much smaller than the PCU with standard silicon power devices.

about 4 months ago
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The World's Worst Planes: Aircraft Designs That Failed

calidoscope Re:Stupid (209 comments)

Except that Boeing, Convair, Douglas and Lockheed figured out how to put windows on pressurized airliners before the Comet flew.

about 4 months ago
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Toyota Describes Combustion Engine That Generates Electricity Directly

calidoscope Re:Efficiency? (234 comments)

The transmissions on current GE and EMD diesel electric locomotives are about 94% efficient from the output of the prime mover to the driving wheels. I would expect electric car motors to be on the order of 90 to 95% efficient, so this should compare favorably with a mechanical tranny.

Speaking of locomotives, the free piston gasifier was being heavily researched in the 1950's as a more efficient realization of a gas turbine and something that could compete with diesel engines as prime movers.

about 5 months ago

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