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Comment Re:what happened with computers? (Score 1) 333

"Computation" may be massless, but "Computers" are not, they are real physical devices that used to be the purview of governments and large corporations due to their high cost. Once cost dropped to the point where the market began to expand, it attracted additional investment in tools and technology that have put us on the virtuous cycle that is Moore's Law. Fabs and chips are still real physical objects that cost real physical money. Building a new fab costs 8-10 $billion these days, 10x as much as what SpaceX spent to develop the Falcon 9, but consumer/enterprise electronics is a trillion dollar business so its a drop in the bucket. If space were to become a trillion dollar business, we'd likely see dramatic leaps in performance and drops in cost. The trick of course is to bring those initial costs below the tipping point where large scale consumer and corporate become interested.

Comment Re:Data data everywhere and not a drop to think (Score 0) 366

. A load sensor installed on each landing gear would easily gather the current weight of the aircraft ( as an example). I'd transmit the data to the flight computer using the ARINC 429 data bus or AFDX used to connect flight peripherals. Does that mean you need to STFU?

Comment Re:Um, it's pretty much over, dude (Score 1) 99

One specific example of the indirect benefits of Apollo, in 1969 the Mothers Club at Lakeside School were debating what to do with the proceeds of rummage sale. One option was a new scoreboard for the school, but the other (which was chosen) and due to all the focus on the space race at the time was to purchase a Model 33 ASR teletype and a block of computer time. This was the computer that Bill Gates and Paul Allen became enamored with.

Comment Re:Not so fast (Score 1) 226

SpaceX has computer model of Falcon 9. It originally showed that they'd be able to recover the second stage. Then reality settled in, once they had real performance numbers and actual flight data, they revised their models and like that it wasn't viable to recover it anymore. SSTO models are insanely sensitive to changes in assumptions. All it takes is 1 or 2 technologies to not pan out exactly as expected and you've got zero payload. X-33 isn't the only one to suffer from this, same thing happened to the X-30, X-34, Kistler and Rotary Rocket, of course then again REL is "just so far head of anyone else". A computer model is exactly that, a model, entirely based on assumptions of material properties and masses. These assumptions don't always line up with reality. The $500/kg number doesn't include amortized R&D costs, which when its going to cost $12B or more (again these are 2004 numbers, with inflation it's now $15B), these are the costs that kill your economics. Skylon themselves have quoted $1000/kg when these are included (as I said, even over 1000 flights, amortized R&D just by itself is almost a quarter of the cost of an expendable Falcon 9). When you factor that in, Skylon isn't much better than Falcon 9

Comment Re:Not so fast (Score 1) 226

The X-33 was also supposed to dramatically reduce the cost of access to space. People had checked "the sums" Of course the problems started to arise when they actually started building the thing. Suddenly it wasn't as easy to build composite conformal LH2 tanks as they thought and the program went from "the SSTO future of cheap space travel", to a rusting curiosity. For Skylon to work, it requires everything to go just right, if 1 or 2 technologies don't pan out, or turn out to weigh more than originally expected, you suddenly have a vehicle that can't carry a useful payload. Every single SSTO project has turned out this way, brilliant on paper, but much harder once metal is bent. Maybe Skylon will be different, but they have a long, long, long road before the first one flies. I can understand the national pride angle (hey I'm Canadian, so I don't even have a bird in the fight), but I'm confident that Skylon will never fly. SpaceX by luck or good planning has stumbled onto a virtuous cycle that puts them on the most viable path to reliability and to reducing the cost of access to space. How: 1. They built a heavily over-engineered largely conventional rocket that has a viable path towards reusability. They can build a little, test a little, get missions under their belt and learn how the Falcon 9 flies and where they can optimize performance (Falcon 9 "full thrust" launches later this year). However even if all these reusability experiments fail for some reason, they still have a profitable launch vehicle. If Skylon fails, they've got nothing, except maybe a very very expensive ballistic transport. 2. All of the R&D flights are on someone elses dime. By building the Falcon 9 larger than what is needed for most LEO payloads, it can fly those payloads at a profit, and then, once the second stage is away, do what ever experiments they wish to test out various recovery options. They are running a viable business while building up the experience and expertise they need to reuse a stage. Most launch vehicles are built to the smallest possible size and then scaled with SRBs so any flight test incurs additional costs (even if its just for the SRBs). Skylon requires $12 billion up front to build a vehicle, someone needs to be willing to invest that money on a vehicle that may or may not work. 3. Development costs, to 2014 SpaceX has invested ~$1 billion to develop both Dragon and Falcon 9 (both their money and NASA's). The initial Falcon 9 version took $300 million to develop (less than what was spent to just develop Skylon's heat exchanger). For argument sake, lets say it will cost SpaceX $1 billion in R&D on the Falcon 9 before they can start recovering stages, and over the lifetime of the vehicle they fly 200 times. That's $5 million per flight in R&D costs. Skylon at $12 billion (and those were 2004 numbers), even it if flies 1000 times, is $12 million a flight in amortized R&D costs per flight (almost a quarter of the price of an expendable Falcon 9). Skylon estimates amortized launch costs at $1000/kg, SpaceX is hoping for $1100/kg, so while operational costs of Skylon may theoretically be much cheaper. when you account for the R&D costs, the differences are negligible (and Falcon 9 is far lower risk than Skylon) 4. Scaleability. To scale Falcon 9, you can stretch the tanks, upgrade the engines, or in the case of Falcon Heavy, stack cores . With the exception of Falcon Heavy, all of these have already been demonstrated. To scale Skylon requires the entire vehicle to be redesigned. In 3 years when REL starts looking for investors to fund the rest of the development of Skylon (even if they now have a demonstrable engine), are those dollars going to flow to a high risk, high cost proposal, or to SpaceX who by routinely recovering and reusing stages has just quartered the cost of launch

Comment Re:Marketing Opportunity (Score 1) 162

WOW, it definitely looks like you know you're talking about. You of course know that the F-35 total program costs include building 2,500 aircraft, upgrades, parts and maintenance for the estimated 53 year lifetime of the aircraft. Lets break it down and assume the most inefficient process possible. We'll use the SLS "Pork launcher", $10B to develop through 2017. Lets assume they spend another $10B to finish the Block II design, and cost it out at $1 billion per launch. NASA's current baseline projects 10 launches per manned mission. We'll assume 7 manned missions (same as Apollo). So we're at $90 billion for launch vehicle development the launches themselves Mars Lander, Hab module and propulsion , lets say another $40Billion to develop and $4 billion a pop per mission. So that's another $68 billion. (Or 2.5 times what it cost to build ISS not including launches). Another $2 billion a year in operational costs over 20 years. This brings us pretty close to $200 billion over 20 years without including any potential cost savings coming from commercial space operators like SpaceX. I'd like to the "delusional thinking" that leads to a spending more than $1.3 trillion to go to Mars

Comment Re:Marketing Opportunity (Score 1) 162

A manned Mars mission would never cost a trillion. Perhaps you're thinking of the whole SEI debacle in the early 90's, this is where we would return to the Moon, build a base, establish a significant amount of space infrastructure and then conduct a mission to Mars. This was costed out in detail and included projected overruns for an estimated cost of $250billion over 20 years ($12 billion a year). However someone in the OMB got the number and decided that "since NASA always has overruns, lets double that to $500billion". Then some Congressional staffer got the $500billion number and decided to double it again to produce the famous Trillion dollar number that the media ran with. Of course like every President since Johnson, George Sr. wasn't willing to spend any political capital on space besides the usual press conference that every president uses to extol the virtues of NASA, change their goals so they have to start all over again, and then never pay it a second thought.

Nothing will ever be attempted if all possible objections must be first overcome. -- Dr. Johnson