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Comment: Re:Baby steps (Score 1) 348

Step 1: research on the ISS focused on biosphere components and food production.

Those aren't baby steps - your step 1 is no lower than about step 5 in any rational plan. We don't even know how to build a biosphere _on the ground_. Baby steps start with the basics, not three quarters of the way up the curve in the most expensive place to perform research.

At the same time, work on high efficiency, low reaction mass propulsion systems.

We already have those. The problem is, they absolutely suck because high efficiency and low reaction mass means absurdly low thrust. (F=MA after all.) Absent new physics, that's not going to change and such drives are going to be useless for manned expansion.

Comment: Re:German illegal? (Score 2) 323

by DerekLyons (#48142775) Attached to: How English Beat German As the Language of Science

And this isn't old news either - that a Presidential candidate (JFK) was Catholic was a divisive issue within living memory.

The problem with knowing the truth of US history is, starting in the 60's the black civil rights movement co-opted the idea of discrimination and painted in simple black-and-white terms. Steadily since then, except for things like the internment of the Japanese that simply couldn't be overwritten, the story of discrimination and persecution in the US has been told solely in terms of antisemitism and Jim Crow.

Comment: Re:The Russian space program was amazing (Score 1) 122

I believe the differences between the two is mostly to the "no nonsense" approach to the Russians, and the fact that they like re-using designs and equipment that work instead of constantly re-inventing the wheel.

Except... they don't re-use designs and equipment. The current mark of the Soyuz (capsule) has almost nothing in common with the early ones other than a reasonably similar moldline. Soyuz has been modified and updated multiple times, not the least as it evolved from a general purpose Earth orbiter into a very specialized station taxi.

Sure, their spacecraft may look "ugly" (or at least, "uglier") than western or American ones, but they get the job done and they are reliable workhorses.

Reliable... is a very shaky claim given the number of near failures and almost disasters suffered by Soyuz over the years. It hasn't killed anyone in a long time, but it's come uncomfortably close an uncomfortably significant percentage of it's flights.[1] And speaking of flights and workhorses... even though it started flying over a decade earlier, it won't match the number of Shuttle flights until somewhere around the end of this decade at the current flight rate. (Last time I looked, I haven't calculated in a while.) In the same vein, while Shuttle suffered two LOCV accidents, it had zero complete mission failures and only one partial mission failure due to an abort-to-orbit placing it in too low of an orbit. Meanwhile, Soyuz had one pad abort, one failure to orbit, and at least two complete mission failures due to an inability to dock with a space station. (As well as several instances of either the orbital module or the re-entry module failing to separate properly.)
All of which is a roundabout way of saying the comparison isn't really as black-and-white as people would like it to be once you compare the actual Shuttle against the actual Soyuz (as opposed the largely fictional Soyuz the actual Shuttle is commonly compared to) and look at the actual numbers.

[1] Here's three accounts just covering reentry and landing failures.

Comment: Re:Ridiculous (Score 1) 139

by DerekLyons (#48075815) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

The point is that Boeing has nothing but mockups, powerpoints, and disastrous wind tunnel tests, so Sierra Nevada doesn't have to do much to have more technical merit.

When it comes to the most important part of it's flight regime, all Sierra Nevada has is "mockups, powerpoints, and wind tunnel tests". Worse yet, that regime is actually an area in which we have very little actual experience (essentially limited to Space Shuttle re-entries).

But go ahead and keep pretending that Boeing won based on the "technical merit" of a less tested, less developed, less capable, and more expensive system.

"Less tested and lest developed" is a relative matter... Boeing has a "less tested and less developed" craft that operates in a (relatively) simple and well understood flight regime. Sierra Nevada has an all but completely untested and undeveloped craft that operates in an extremely complex and little understood flight regime. Their flight tests to date, all low altitude ad subsonic, have nowhere approached the regime where the questions reside, not even close.

That you have to have this pointed out to you *twice*... well, further proof that you're a clueless fool.

Comment: Re:Maybe affects Boeing, not SpaceX (Score 1) 139

by DerekLyons (#48074799) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

I really doubt SpaceX is going to stop work on a vehicle they were developing before they were awarded the contract.

If they don't, then the costs of work they perform cannot be reimbursed under the contract. Further, not doing so may also result in significant penalties being levied for breaking the terms of the contract.

So SpaceX may or may not stop work entirely, but they *will* stop any NASA specific work and may have to stop work that's not necessarily NASA specific but is being paid for under the contract. (It can actually get pretty complicated at this level.) Your faith in SpaceX is touching and charming, but it utterly at odds with the real world.

Comment: Re:Ridiculous (Score 1) 139

by DerekLyons (#48074729) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

I interpreted Firethorn's first point to be that the shuttle was designed to retrieve and bring back to Earth a large object, but none of the objects it actually did return to Earth were that large.

The Shuttle was generally limited more by CG than by weight or physical size. That being said, STS-32 did return the LDEF, which pretty much filled the payload (but was actually pretty light for it's size). Any number of ISS flights returned a Spacehab or MLPM at pretty much the maximum weight the Shuttle was capable of boosting to the that orbit.

I'm not sure why that capability was included in the original design; if it was included in case a bad but still reasonably possible scenario happened then retroactively removing it from the design seems like a bit of 20/20 hindsight.

If you take off with a payload - then you need to be able to land with that payload in an abort scenario, whether it's as (relatively) benign as an ATO or the screaming horror of the RTLS. Once you've certified the design to return with a full payload under the worst case abort scenario, that you now have the capability to do so in normal operations is pretty much axiomatic.

That being said, there were actually three payload return weight limits;

  • Normal processing - the loads were below that which would damage the shuttle.
  • Special processing - the loads could damage the shuttle and would require a mandatory OMDP on return in order to conduct an inspection and analysis of the structure.
  • One time - the loads would almost certainly damage the Shuttle and while it could land safely and intact there would be a significant chance of the vehicle subsequently being written off. This option was actually exercised once, for the Chandra X-Ray Observatory, which was the heaviest payload ever boosted by the Shuttle.

Comment: Re:Ridiculous (Score 1) 139

by DerekLyons (#48074429) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

I agree that it's not as obviously gamed as everyone says.

Very few people actually discussing this issue (here on Slashdot and other geek/fanboy fora) have the knowledge to actually evaluate these proposals. Add in a strong anti-corporate bias, a strong anti-NASA bias, and the geek cool factor of having a space plane that avoid the "obvious" flaw of the Shuttle's parallel mounting... and you have people essentially making judgements on the process on what amounts to religious grounds.

I'm as cynical as the next guy when it comes to politics, but there is certainly more to it here.

Which is pretty much my point... the answer lies in the technical issues, which are *MUCH* thornier than most people grasp.

Comment: Re:Ridiculous (Score 1) 139

by DerekLyons (#48074337) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

One some planet where the aerodynamics of a winged craft are in any way comparable to a ballistic re-entry... your comment would make sense. In the real world, where the Dream Chaser hasn't been flight tested in anything even remotely close to the most difficult portion of it's flight regime... you just come off as clueless.

Seriously, you have no clue what you're talking about if you think the equivalent of turning the engine over "proves" that a car will be the fastest and best performing in the Indianapolis 500.

Comment: Re:Ridiculous (Score 4, Insightful) 139

by DerekLyons (#48071081) Attached to: NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

A space plane isn't inherently unreliable. Placing said space plane below the level of cryogenic fuel tank insulation, with ice subject to crashing into it at hundreds of miles an hour is, in retrospect, pretty silly. Dream Chaser (DC) sits at the top of the rocket stack - it's smaller than the space shuttle, so this is feasible.

Putting the space plane on top of the stack isn't without it's own problems though... mainly in the form of huge aerodynamic issues because the wings are now where they can exert the greatest leverage. (Read among other things: in the exact right spot to cause the most control problems and to tear the stack to shreds if there's only a small problem with the angle of attack.) That's why the Dyansoar's Titan booster had suchhuge fins, simply gimbaling the engines did not provide sufficient control authority to offset the resistance of the wings.

For the record, as a huge fan of Spacex, I don't think the DC needs to be trashed on - it was a good (not great) proposal stuck between the big PR darling and the politically best-connected contractor in the business.

You forgot: "and was the most technically difficult proposal and submitted by the contractor with the least experience of any kind". Sierra Nevada has no substantial grounds for complaint, their solution may have been competitive on price, but contrary to popular belief these types of contracts are NOT awarded solely on the basis of costs. Technical factors also play a huge role. Which also explains the award to Boeing, it wasn't political connections, it was because SpaceX has a damm poor track record when it comes to delivering on time.

Comment: *Sigh* Once again, the half truths. (Score 5, Interesting) 125

by DerekLyons (#48065597) Attached to: How President Nixon Saved/Wrecked the American Space Program

Logsdon and Callahan, for reasons best known to themselves and like so many others, continue to mythologize the space program... to the detriment of the facts.
They forget, as so many do, there's a third President (Johnson) and a number of years between President's Kennedy and Nixon. Nixon's policy decisions were shaped largely by decisions made by and during the Johnson Administration by the President and Congress. Most notably, in the budget battles of '65-'67 Apollo's budget was sharply cut, capping hardware production (and thus limiting the number of landings) and all but cancelling the follow on Apollo Applications program. During the same period, both NASA management and the Administration began to concentrate on the Shuttle as an Apollo follow on as cheaper access to space began to loom as a more important national priority than flags-and-footprints stunts. Nixon was thus caught between a rock and a hard place - inheriting (as every President after him has) a rudderless, directionless mess that would take far more money to fix than the public would stand for and far more political capital than the returns could possibly justify.
And really, Apollo has screwed us up in space pretty much for all time... Because it's lead too many people to believe that progress is only made by Great Leaps Forward. Because it stuck us (as a nation) with a bloated and inefficient NASA bureaucracy. Because it's blinded too many people to the fact that it was an accident of history and a detour from any rational path of space development.

Comment: Re:Faraday Cage / Tempest (Score 1) 142

by DerekLyons (#48042727) Attached to: Boeing Told To Replace Cockpit Screens Affected By Wi-Fi

First, I would hope that the avionics themselves were shielded and tested before deployment and use. I mean, we don't want the altimeter interfering with the artificial horizon, do we? (stupid, simple, but real example)

They are shielded and tested before deployment. But no testing is 100% effective, ever. And EMI is a tricksy thing to test and shield against.

Second, the whole cockpit and supporting avionics and other fight critical systems are in an enclosed conductive vessel, ie the cockpit and support area. It's a Faraday cage within a larger Faraday cage (the aircraft)

First off, the cockpit and other systems are not in an enclosed conductive vessel - they're part of the main fuselage, just like the passenger cabin. Second... the aircraft is not a Faraday cage, or at least not a very effective one as a broad range of frequencies can be received in the passenger cabin.

Polite language: you haven't a clue what you're talking about.

Comment: Re:net metering != solar and 10% needs new physics (Score 1) 488

by DerekLyons (#48025381) Attached to: Energy Utilities Trying To Stifle Growth of Solar Power

The utility company already has a lot of the hardware anyway.

Um, no. They have precisely none of the hardware.

I'm not talking about what it would cost me to build my own battery buffer - I'm talking about the incremental cost to the power company to include me in their power buffer.

Well, no. The power company has all the other costs I mentioned as well. Failing to include them is misleading.

That I'm doing so with consumer-oriented prices should be taken as evidence that I haven't a clue what I'm talking about

There, fixed that for you.

"The only way for a reporter to look at a politician is down." -- H.L. Mencken