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Comment Flaws in Liquid Solid Engine (Score 4, Interesting) 112

I have been reading lately that there has been serious concern about the liquid-solid hybrid engine used in Spaceship 2. In 2007 there was a nitrous oxide explosion that killed three people.

On 26 July 2007, during the early rocket testing phase, an explosion occurred during a propellant flow test at the Mojave Air and Space Port. The test included filling the oxidizer tank with 4,500 kg (10,000 pounds) of nitrous oxide, followed by a 15-second cold flow injector test. Although the tests did not ignite the gas, three employees were killed and three injured, two critically and one seriously, by flying shrapnel.[12]

parabolicarc.com is a pretty good source of information on New Space. Here are some tweets:

Parabolicarc.com @spacecom Oct 31

I had deep concerns over both the new plastic/nitrous oxide engine and so did other sources familiar with the testing. #SpaceShipTwo

The concerns were three fold. One, that it wasn't being tested sufficiently on the ground before it was flown. #SpaceShipTwo

Second: that modifications required to ship to accommodate the new engine introduced additional complexity and failure modes. #SpaceShipTwo

Third, handful of test flights they were doing with new #SpaceShipTwo engine before putting Richard and Sam Branson aboard were insufficient

Let me stress2 things: one, we don't know what happened yet, so I'm not making a snap judgment about what caused the accident #SpaceShipTwo

Second, these concerns about the new engine were not mine alone. Folks much smarter and knowledgble than me were worried. #SpaceShipTwo

I predict you will be hearing a lot more about these concerns and the problems they were having in the days and weeks ahead #SpaceShipTwo

Scaled's Kevin Mickey called the engine change "a minor nuance". He rushed out of the press conference once it was over.

Mickey claimed "minor nuance" engine change thoroughly tested on ground. Tried to ask for details, but presser ended quickly & Mickey left.

Ken Brown was taking photos through the entire incident. Tracked one large piece of debris down to the lakebed. #SpaceShipTwo

I heard Ken say, "They're in trouble." And then "They're tumbling. Ken's pictures will be very crucial to understanding it. #SpaceShipTwo

Just talked to Ken Brown. Pictures show Engine fired fine, then there's a white plume. He thinks the nitrous oxide tank blew. #SpaceShipTwo

I am a huge supporter of commercial space, most especially Space X. But I think that accidents like this give the whole sector a bad name. Virgin Galactic/SC have been building this ship for 10 years, and they still don't have a viable engine. That is not a good sign.

Contrast that with Space X, which in about the same amount of time has built the Falcon 9, which has a string of 13 straight successes (touch wood). It seems to me that not all space companies are created equal.

Comment Re:Elon Musk Called it Two Years Ago (Score 1) 443

The engines were probably fine, chances are it's something to do with the fuel delivery system that caused the explosion.

The Russians built good engines, and they built a lot of them because they anticipated needing many to get to the moon. Rather than a few big engines like the Saturn V they were using 30 odd smaller ones to do the same job. They had some problems but eventually got it working, just because they abandoned the idea of manned moon missions.

My guess is that it was a turbo-pump that failed. Those are a part of this Soviet engine, and were also likely made in the 1960's.

Comment Elon Musk Called it Two Years Ago (Score 5, Insightful) 443

Elon Musk called it two years ago in this interview.

Musk: The results are pretty crazy. One of our competitors, Orbital Sciences, has a contract to resupply the International Space Station, and their rocket honestly sounds like the punch line to a joke. It uses Russian rocket engines that were made in the ’60s. I don’t mean their design is from the ’60s—I mean they start with engines that were literally made in the ’60s and, like, packed away in Siberia somewhere.

Comment Re:All very sad (Score 1) 443

NASA spent many years developing processes and vehicles that, initially, had a very high failure rate. Today we are conditioned to expect that these launches will go off safely, but do we need to give the private sector 20 years or so to sort itself out before we start allowing people to fly in their rockets?

Almost all the US space program is ALREADY private. The dominant US launch platform is United Launch Alliance, which was created by a merger of Lockheed Martin and Boeing when the US tried to bring in competitive bidding for Air Force launches. Their merger allowed them to become the sole bidder on most launches, allowing them to continue to receive their cushy "cost plus" bids. These "cost plus" bids allow them to pretty much charge whatever they want for costs, and then receive on top a guaranteed profit margin. There is no incentive for efficiency. In fact, ULA has almost no international customers because their costs are more than double their competitor's prices. They grow fat at the teet of the US Air Force.

Space X is a relative newcomer, but since its first generation rocket (Falcon 1) had three failures, the last of which was caused by a timing error in stage separation, it has had a nearly perfect launch record. The Falcon 9 rocket has never had a significant failure (ie. one that prevented orbit of the primary payload). Touch wood. Their rockets have been designed in house with the eventual goal of re-use. Their rocket engines are designed to be simple and failure resistant. And their rockets have nine engines, so that even if one fails the flight can continue. I wouldn't write off competition yet.

Comment Re:Horrible track record (Score 1) 443

I seem to remember a SpaceX rocket accidentally self destructing recently. And people have died serving NASA missions. Tell me who has this illusive awesome track record you are looking for?

It was a test vehicle that self-destructed, and not a full rocket. The test vehicle did not have all of the redundancies of the production rocket. A single sensor failure stopped the rocket. In the real rocket, there are multiple redundant sensors from which the control systems constantly poll...if one goes, the computer ignores it in favor of the other working sensors.

Comment Obligatory Socrates Quote (Score 1) 306

When I left him, I reasoned thus with myself: I am wiser than this man, for neither of us appears to know anything great and good; but he fancies he knows something, although he knows nothing; whereas I, as I do not know anything, so I do not fancy I do. In this trifling particular, then, I appear to be wiser than he, because I do not fancy I know what I do not know.

From Socrates, The Apology (399 B.C. or so)

Everything old is new again.

Comment Re:Left one out (Score 1) 306

The problem here is that Prof. Dunning's principle could apply to anybody, including college professors. So how does he know he is correct? --- "Science is the belief in the ignorance of experts." -- Richard Feynman

Are you sure about that?

Comment Re:Satellites were Once Considered Crazy (Score 1) 352

Elon Musk is in many ways like Werner Von Braun

You mean he's a mass murderer who used technology to rain down death onto the allies? Wow.

Von Braun risked his life to even think about using his rockets for space travel while working under the nazis. He almost single-handedly dragged the Americans into the space age. He is not perfect. But he did change our world in a positive way.

Comment Satellites were Once Considered Crazy (Score 2) 352

This article argues that Elon Musk is in many ways like Werner Von Braun or the Soviet scientist Sergei Korolev (who pushed the Soviets into space). One thing I got from this article was that the original and primary motivation for building rockets was to make weapons. Von Braun and Kovolev almost singlehandedly pushed their own countries into building rockets to put people into space. Without them, we might not have had satellites as quickly or at all. Placing satellites into orbit and putting humans into orbit was once considered crazy. American government officials considered Von Braun to be eccentric, but they didn't care as long as he gave them better ICBM's. Now our entire civilization is built around satellite technology, and our moon shots have brought us technology advances such as the microchip.

When we talk about putting more humans it can sound a little crazy. However I don't think it is any more crazy than having people climb Mt. Everest, having bases in Antarctica, or sending three small ships westward into the unknown ocean to find a new world. We humans have an inbuilt desire to explore. To ignore that is to go against our fundamental nature.

Comment Re:Other things they said couldn't be done... (Score 1) 571

At any rate, when I become annoyed enough, I respond with evidence oriented responses. I find references to uphold my position, and include quotes and links. Now someone may disagree with me, but at least I am not making assertions based solely on my individual position. I am generally disappointed because very few people respond with their own external references.

Agreed. Thus my signature. Sometimes I feel like slashdot is like this:

O: Yes it is!

M: No it isn't!

(pause)

M: It's just contradiction!

O: No it isn't!

M: It IS!

O: It is NOT!

M: You just contradicted me!

O: No I didn't!

M: You DID!

O: No no no!

M: You did just then!

O: Nonsense!

M: (exasperated) Oh, this is futile!!

(pause)

O: No it isn't!

M: Yes it is!

(pause)

M: I came here for a good argument!

O: AH, no you didn't, you came here for an argument!

M: An argument isn't just contradiction.

O: Well! it CAN be!

M: No it can't!

M: An argument is a connected series of statements intended to establish a proposition.

O: No it isn't!

M: Yes it is! 'tisn't just contradiction.

O: Look, if I *argue* with you, I must take up a contrary position!

M: Yes but it isn't just saying 'no it isn't'.

O: Yes it is!

M: No it isn't!

O: Yes it is!

M: No it isn't!

O: Yes it is!

M: No it ISN'T! Argument is an intellectual process. Contradiction is just the automatic gainsaying of anything the other person says.

O: It is NOT!

M: It is!

O: Not at all!

M: It is!

Comment Re:Sounded real promising right up to.... (Score 4, Insightful) 571

Sounds real promising right up to "operational within a decade" that's code for we have an idea that on paper sounds like it might possibly work. Please give us lots of money.

Oh puleeaze. This is Skunkworks. Thomas McGuire did his PhD thesis on fusors at MIT. This isn't just some investment scam. Do some research.

Comment Re:Other things they said couldn't be done... (Score 1) 571

Yeah. I'm somewhat disappointed that shallow dismissive/mocking comments seem to outnumber more engaged comments by three to one. We are supposed to be geeks. How many of us have heard about this reactor? It was announced many months ago. How many of us have searched the term "high beta reactor"? This development is potentially world-changing. It would solve the world's energy problems. It would make human deep space travel feasible. And the announcement is coming from a credible scientist from a credible laboratory.

I am beginning to suspect that slashdot is getting spammed by agenda driven posters.

Comment Re:Amazing if it works (Score 4, Interesting) 571

But plenty of fusion reactor designs have worked in theory; making them work in practice, though...

Yes, but this is Lockheed Martin. And we live in the age of computer aided design, where we can simulate much of an object before building this. In addition, I'm fairly sure that they have built smaller versions of this as proofs of concept. And now they have Thomas McGuire making the announcements, who is the lead scientist on the project, instead of the project manager doing presentations. He wrote his PhD thesis at MIT on fusors.

I am inclined to believe that this is the real thing. My main question is this: They use radio frequency radiation to heat the plasma; how have they overcome the rf shielding effect caused by hot plasma?

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