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Comment Re:No Gut no Glory (Score 1) 67

But some of the things they're trying are just so new that unexpected failure modes are bound to appear.

It would have been better for them if detecting the unexpected failure mode of supercooled LOX penetration of the carbon fibre windings on the helium bottle had been done on the ground in a test rig rather than in a complete stack on the launch pad. That's what testing in aerospace is meant to do and part of the reason launches are so expensive.

SpaceX is now required by launch customers to carry out hotfire tests without the payload being integrated -- this means the launch vehicle has to be rolled out to the pad, hotfired then returned to an integration facility, have the payload installed and then the completed stack rolled out to the pad again. This adds extra costs in time and money to a launch. It may be that in the future, after racking up a number of trouble-free launches their customers will opt for the cheaper option of integration/rollout/hotfire/launch but for now the cost of the extended procedure is going to have to be eaten, probably by SpaceX. Thorough testing might have been cheaper in the long run.

Comment Re:No Gut no Glory (Score 4, Insightful) 67

SpaceX isn't doing the rocket business the way other rocket builders do. That's a plus and also a minus on their part.

In this case they tried something new, supercooling the fuel and oxidiser to improve launch performance. Older fuddy-duddy rocket builders, if they decided to try this sort of thing would spend a couple of years and hundreds of millions of dollars trying the concept out, building prototypes, testing them to destruction and analysing the parts microscopically to see what happened to them. SpaceX did the equivalent of compiling the code and running a few unit tests and when nothing broke they beta-tested it with a paying customer's payload on top. Oops.

A previous launch failure was due to a third-party strut failing under load -- again SpaceX cut corners by not testing each and every component, accepting the risk of a failure rather than spending time and money on eliminating a one in a million possibility. This is something the older rocket builders do as a matter of course with the customer paying for it in the launch pricetag.

They're learning their lessons but it's costing them money, time and more importantly reputation. More rigorous testing will push the price of launches up and that eats into their low-cost launch niche while other contenders with proven track records of not cutting corners are pushing down into that market bracket (ISRO for one).

Comment Re:Riiiiight (Score 1) 202

Turn that around. When has Microsoft actively killed a tool that was highly depended upon in enterprise without offering an alternative?

Small Business Server (SBS). It was cannibalising sales of their more expensive low-end server offerings so it had do go despite being just the job for man-and-a-dog companies. Of course some might say that businesses like Joe's Garage isn't "enterprise"...

Comment Re:Not Enough (Score 1) 147

Near as I could figure it, Fraunhofer doesn't do coal, they only offer renewables (solar and wind) so it's not relevant. Here's a result from Google showing in chart form the last ten years or so of German electricity production (2005 - 2014):

http://energytransition.de/201...

Over the ten year period shown in the first chart non-carbon-emitting green nuclear production is down, renewable production is up and CO2-emitting coal and lignite production is not changing very much. The lowest production was in 2008 and 2009 during a world-wide recession.

As I said before, the non-carbon nuclear supply (currently about 95 TWh) is going away totally by government diktat in 2023. The projected increase in renewables will probably cover that loss in generating capacity (although renewables aren't a good replacement for baseload generation without lots of expensive storage or backstop fossil-carbon gas CCGT) but it means Germany will be still burning lignite in ten years time at the same rate it does today to keep the lights on. It's either that or freeze in the dark.

Comment Re:Not Enough (Score 2) 147

There is zero evidence that Germany plans to abandon burning lignite any time this century, never mind 2040 or 2060. There have been lots of fanciful announcements about renewables taking over and the end of fossil CO2 emissions but the facts don't agree. Ten years ago Germany generated about 40% of its electricity from coal and lignite, about 290 TWhrs. In 2015 it generated about 40% of its electricity from coal and lignite, about 270 TWhrs. The increase in renewables generation over that period has been balanced by a reduction in nuclear non-carbon baseload generation, from about 25% to 15%. That 15% is going away totally by 2023 when the last nuclear power station will be closed by government order. Either the Germans spend a lot more on building out their renewable fleet, improving their grid to handle the fluctuating supply, add large amounts of storage and start replacing their first-generation wind turbines and solar installations which are reaching end-of-life, or they burn more lignite. My bet is on the latter.

Comment Re:Not Enough (Score 2) 147

Germany has no intention of eliminating fossil fuel burning in the near or even the far future. At the moment they generate 40% of their electricity demand from coal and lignite. They *hope* to have reduced their coal and lignite consumption by 2050 but it's a big industry and employer, and they have billions of tonnes of extractable lignite resources within their own borders so it's not going to disappear completely. They have legislated the shutdown of their non-fossil nuclear power plants by 2023 and that means they will have to find another 15% or so of replacement generating capacity when that happens. A lot of that coming shortfall could be covered by burning more coal.

Comment Re:What Hollande says (Score 1) 328

So, for the US, reprocessing must not be economical or it would be happening already.

Freshly-mined uranium is cheap and plentiful and a once-through cycle of mining, enrichment and consumption is less expensive than fuel derived from current spent fuel reprocessing systems, in part because they are based on military-style weapons-grade plutonium production (the PUREX process) since that was the first method developed to deal with spent fuel. There is some research going on into lower-cost and simpler spent fuel reprocessing but it's not a priority given the low cost of fresh uranium and yellowcake production at the moment.

France and other nations such as Russia, Britain and Japan reprocess spent fuel for other reasons -- it vastly reduces the volume of material needing to be stored for long periods of time, for one thing. The Russians are working on advanced fuel cycles to burn spent fuel in fast reactors like the BN-800. Japanese have a breakout capability to make nuclear weapons if they decide to -- The Monju breeder, the reprocessing plant at Rokkaisho and they even have the small Epsilon orbital launcher to repurpose as an ICBM if they choose.

Comment Re: it estimates will be worth 250 billion euros (Score 1) 68

Accuracy per se isn't the real advantage of adding Galileo to the existing Navstar and Glonass global positioning satellite networks since better fix data is more dependent on correction overlay services like WAAS in the US and EGNOS in Europe, using fixed ground stations to provide extra accuracy information to GPS receivers allowing, for example, safe automatic landing of aircraft and shipping movements through restricted waters.

The main benefit of having a lot more GPS satellites in orbit is in places such as cities and mountainous regions where the skyview is restricted and it is possible to lose simultaneous line-of-sight to the four satellites required for a correct position/altitude/velocity result. More satellites means fewer blackouts for a given receiver in such situations.

Submission + - ESA launches four Galileo satellites (esa.int)

nojayuk writes: From the ESA website: An Ariane 5 rocket has launched four additional Galileo satellites, accelerating deployment of the new satellite navigation system. The Ariane 5, operated by Arianespace, lifted off from Europe’s Spaceport in Kourou, French Guiana at 13:06 GMT (14:06 CET, 10:06 local time) carrying Galileo satellites 15–18. The first pair was released 3 hours 35 minutes and 44 seconds after liftoff, while the second separated 20 minutes later. The Galileos are at their target altitude, after a flawless release from the new dispenser designed to handle four satellites.

This was the first flight of a heavy-lift ES-variant of the Ariane V since the ATV resupply missions to the ISS. Previously Galileo satellites have been launched in pairs by Soyuz-Fregat craft from French Guiana. Two additional Ariane 5 launches each carrying four Galileo satellites are scheduled in 2017 and 2018. The full system of 24 satellites plus spares is expected to be in place by 2020.

Comment Re:WTF? (Score 1) 107

Technically, a uranium tamper is still fissioned with fast neutron flux

Not quite. Uranium-238, the main component of depleted and also naturally occurring uranium doesn't fission. It WILL breed up into Pu-239 through neutron capture via an intermediate product and that will fission and produce energy if hit by neutrons.

Natural uranium has about 0.6% U-235 which will fission so it's a better tamper than depleted uranium which is usually about 0.2%-0.3% or so, providing more bang for your buck as it only takes one neutron to cause an atom of U-235 to fission whereas the U-238->Pu-239 breeding and fission process requires two neutrons. This all has to happen in a short period of time, too before the expanding bubble of fissionable material gets too large.

Comment Re:Wake up call - Jobs is dead (Score 1) 299

Jobs hated holes in his Precious. There are few holes in the current generation of Apple hardware. Jobs adored slim, the new laptops and phones are slimmer than ever. The legacy is being carried on all too well, with a dead man at the helm.

Comment Re:So... (Score 1) 156

ESA have already put two space observatories, the Herschel infrared telescope and the Planck cosmic microwave background telescope into the L2 location. The JWT is being launched and deployed by ESA so it's not an absolute first for them.

ESA is paying for the launch and that entitles European scientists access to the instrument and data collected by it.

Comment Re:Good, then we can scrap that stupid f-35 (Score 0) 325

And those forward operating bases need to be protected from enemy raids so adding hundreds of troops, vehicles, fuel, logistics etc. to the front lines. The backfield bases operating planes like the F-15SE are usually already in place in friendly territory or on carriers and they can do the same job or better than the A-10 without the frontline logistical load.

Basically the A-10 is an older weapons system in a world which has moved forward. The F-35 is a sniper picking off targets from beyond light AA range (MANPADs, heavy machine guns and rapid-fire cannon) while the A-10 conducts hand-to-hand combat with the enemy if it tries to use its Big Stupid Gun. It's not like it can fly without the BSG either, the entire airframe is built around it. Other aircraft can carry guns with similar capabilities in terms of rate of fire in conformal packs or underwing if the mission requires it but they don't HAVE to cart them around if they're not needed.

The A-10 is stiffy-inducing like battleships. They're obsolete like battleships and a waste of manpower and effort like battleships. There are folks who think battleships should be in the armoury today, for no real reason other than the stiffy they induce. The A-10 is a flying battleship, basically.

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