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Comment Re:rocket up and down video (Score 1) 167

I am not a rocket expert but this is not a question to rocket experts, this is an economics question. Taking up fuel instead of cargo and using fuel to bring back the launch vehicle safely as opposed to parachuting the launch vehicle (or its engines, the most complex part) and launching more useful cargo into orbit.

The question is about cost of production of a rocket and cost of fuel and cost of unit of cargo per launch, not about difficulty of a controlled descent. Assuming it's perfectly easy to do a controlled descent (which is probably much more difficult to do from a much higher altitude than a few dozen meters above Earth, given that the rocket also needs to reorient itself and maneuver a much longer distance down to the surface) then the question is: how much cargo are you not taking up because you are taking up a huge amount of fuel to do this controlled descent, so it's not just a question of cost of fuel, it's a calculation of cost of launch of unit of cargo and cost of launch in total, etc.

One thing I don't have to be a rocket scientist to know is that if you do this, you are not being very efficient with your rocket, you are using huge amount of fuel just to haul fuel, you are not launching as much cargo as you can. You are launching and landing fuel. Then why not launch more cargo and a parachute to land some of the launch vehicle and instead work on manufacturing the rocket cheaper, more efficiently with a manufacturing conveyor line, with robots, with fewer people?

Why not use the money to improve efficiency of manufacturing of the rocket?

Musk wants to be in this business end to end, he wants to manufacture rockets and launch them and do everything. I don't need to be a rocket scientist to know for sure that he will not be as efficient at all of these as he can be at just some of it, that's why we have complex supply chains and specialisation.

Maybe he wants to be a total solution, but that would be Apple of space, not Linux of space so to speak. How about concentrating on the manufacturing side, creating the production process that is the most efficient and the cheapest and then mass producing launch vehicles for all who want to launch and operate them?

No, you don't have to be a rocket scientist to look at the overall business model.

Lets say a disposable rocket costs 150 million, thats 150 million per launch.

If a reusable rocket costs 300 million and gets 10 launches thats 30 million per launch, if it costs 600 million thats 60 million over 10 launches, if it costs 1 billion, thats 100 million over 10 launches. A reuseable rocket can potentially save a lot of money even if it is vastly more expensive.

Considering he is figuring out how to make his current rockets reuseable this will make launches dirt cheap. As fuel is only 2.5 % of launch costs even if you double it relative to cargo orbited to make the rocket reuseable, you still save a lot of money. If a rocket costs 200 million, and fuel costs 5 million, if you only launch half as much cargo but get to reuse the rocket 10 times you spend 50 million on fuel to save 800 million on the 10 replacement rockets you would have destroyed if you launched at full capacity on a disposable rocket. Thats 750 million dollars saved if you only launch at 50% capacity. As a rocket is much lighter landing than taking off launch capacity will likely be reduced by less than 20% which means 1.45 billion in savings over the 8 disposable rockets for the same mass orbited. Thats 250 million for 10 uses of a reuseable rocket vs 1.64 billion for 8 disposable rockets and fuel for the same mass orbited. Thats around an 85% reduction in cost per unit of mass orbited.

The only cost between launches will be recertification and refueling, If the rocket is designed right, recertification will be cheap (10-20% of manufacturing cost or less). Reuseable rockets will also increase manufacturing efficiency, as every man-hour spent on the manufacturing line will enable 8 times as much mass orbited as a disposable rocket, which means reuseable rockets increase manufacturing capacity by a factor equal to the number of times a rocket can be reused times the percentage of capacity lost to recovery. A rocket that can be used 10 times to launch 80% of the mass of a disposable will increase manufacturing capacity by a factor of 8 as 1/8 as many rockets will have to be made per unit of mass orbited. If the rockets can be reused more than 10 times it gets even cheaper.

You don't have to be a rocket scientist to look at the overall business model, but having a grasp of basic mathematics really helps.

Comment Re:How about a bullet-proof skull then? (Score 3, Informative) 74

Can someone knowledgeable (i.e. not speculating) or working in the medical device industry explain why we can't use some really hard material like a titanium alloy or Kevlar to make the skull bullet-proof, especially for those in combat?

Transfer of Kinetic Energy. If you just used a hard bullet proof material the kinetic energy would pass straight through and liquefy the brain.

To make a bullet proof skull you would have to use a hard outer shell, a collapsable inner filler to absorb the kinetic energy and a hard inner shell to prevent spalling from shredding the brain. With current materials science it would be ridiculously thick and heavy and cause more problems than it would solve unless you could reinforce the spine and neck muscles, and it would have to be replaced/rebuilt after every impact.

Take a look at the size and thickness of current combat helmets to see what I mean, and remember that current helmets will not stop a high caliber round or an armor piercing one in a direct impact. They only protect against shrapnel, glancing blows from assault rifle rounds and some light pistol rounds under the right conditions. They have to be discarded after one serious protective use as they are designed to stop the damage by sacrificing their structural integrity (they only stop one hit in the same spot).

Comment Re:Scientologists have been doing this for decades (Score 1) 110

I was 15 years old at the time I read those books, 3/4 of my social circle was into various drugs, L Ron Hubbard's books kept me sober not from the message, but simply because he was serious. That he wasn't trying to write a parody or comedy, that he actually thought he was writing a serious work of literature is something that haunts me to this day. In writing those novels Mr. Hubbard created the most potent warning against drug use that the human race has ever known, the mere fact of their existence is a warning to all mankind of the dangers of drugs. The epic and colossal amount of fail which those novels contain is beyond the ability of words to convey.

20 years later I still have nightmares about the suckage contained within those books. At the mention of Hubbard's name I am compelled to warn others of the horror contained within those pages, a compulsion that is not sated until I find a library copy of his books, steal them, and burn them while screaming DIE DIE DIE as I bludgeon the embers with an axe. For weeks afterwards I mutter curses and deprications against his name, ocassionally screaming them at passerby as I walk down the street. Eventually I forget about the horror until somone mentions his name and the cycle begins again.

The psychological trama those books inflict on their readers is permanent, please don't let my suffering go to waste -- DONT LET KIDS READ HUBBARD.

I admit it, I need help, but I'm too scared of drugs to see a shrink.

Comment Re:Scientologists have been doing this for decades (Score 4, Funny) 110

How do you think all those gods-awful L. Ron Hubbard books got on the best seller lists? The cult members were ordered to buy as mony copies as possible of *every single book*, then they would return them to the book store a week later. And if the stores refused them, they'd "contribute" the stores to libraries.

This explains why the public library I visited when I was a kid had the entire Mission Earth series. It was quite possibly the most horrible thing I have ever read. I read the entire 10 book series in 2 days because it was so utterly insane, so incredibly bad that I couldn't stop reading. It was obvious that copious quantites of powerful mind altering substances were used in the creation of those novels.

I remember thinking to myself as I read :

This is a product of mind on drugs...

lots and lots of drugs...

very powerful drugs... "

If this is what LSD does it is very very very bad.

It was because of L Ron Hubbard and his Mission Earth series that I resolved never ever to use LSD or any other hallucinogen. Anything that could inspire the type of warped, demented and utterly insane thought that went into those books and the poor judgement that resulted in releasing those books for public consumption was clearly a bad thing to be avoided at any cost.

Comment Re:Fix acquisitions (Score 1) 484

I never said anything about public versus private. I think defense is an industry that needs both. What I said is simply to make those that bid for a program to actually be held accountable for and adhere to the terms of the bid that they propose. If we do that, we will save a lot of money.

The problem is twofold, military contracts are often on technology that is brand new or theoretical and proven only by a prototype. Turning new science into a finished product that can handle sustained operations in wartime conditions is expensive and prone to cost overruns. Second, the lead time on military contracts is such that technology changes between the time the contract is issued and delivery. These technological changes can make the product as initally specified obsolete unless changes are made, which leads to cost overruns. Even in an honest system new development of military equipment is expensive.

That said, the current system is horribly inefficent because in order to even get a contract approved contractors have to play games with the inital costs and jump through hoops in order to get congress to approve it. Many ovveruns are caused by contractors later adding in the real costs that wouldn't have been approved if they were known in advance.

As long as the procurement system requires corruption in order for ANY contract to be approved only corrupt contractors will bid and taxpayers will be stuck with outrageous bills.

Comment Re:Look at the Pentagon suppliers (Score 1) 484

The real markup is taxation, companies that take government contracts have to pay taxes on that income and on the income of the employees that work for them. As every dollar spent on a government contract comes from taxes, the prices the government pays are inflated by the amount of taxes the company has to pay back to the government. If we passed legislation exempting government employees, contractors and the employees of government contractors from taxation in direct proportion to the amount of tax dollars they recieve as income we would reduce the cost of government services and contracts by about 25 -30 % without affecting the amount of services delivered.

Comment Re:I say cut the F-35 (Score 1) 484

Yeah, you were proved wrong the past five years, after a "free-market" economy fell flat on its face, and WE got the bill. Please, just shut up with that asinine argument that history has, again and again, proven WRONG.

Calling the current economic conditions in the United states a "Free Market" is utterly absurd. In a free market the government doesn't place artificial barriers to entry in the form of corupt regulations, it doesn't mandate that companies make sub optimal buisness decisions then bail them out when they go under, It doesn't pick winners and losers by placing punitive fees and taxes on activities it doesn't like and redistribute those funds to activities it does like.

While some regulations are absolutely necessary to maintain a free market and restrain the worst abuses of capitalism, what we have now is not a free market economy. The current conditions are closer to crony capitialism and a centrally planned economy than a true free market, and crony capitalism and central planning is what doesn't work.

Comment Re:For the life of me (Score 5, Informative) 525

I don't understand why everyone is so gaga over these Tesla's. Is it a beautiful car? Yeah. Is it well made? Yeah. But, the base price remains at $57,400. This is not a car for the masses. It's like writing about an all-electric Mercedes. Who cares?

As I understand it Tesla's buisness plan is to first make a high performance sports car (Roadster) to work out the bugs in the technology, then make a cheaper sedan to scale up production of components as the more components that are made the cheaper they get. Once enough production capacity is built they can then make cheaper cars using what will then be off the shelf components.

It's the chicken and the egg problem - if nobody mass produces electric cars they will never get cheap, so by mass producing lots of expensive high performance cars they build up the infrastructure to support making cheap ones.

Everyone is going gaga over Tesla because they are succeeding, and with each car they sell we get that much closer to having a cheap yet powerful electric car.

Comment Re:Some insulation sure would help (Score 1) 215

As a lifelong rural inhabitant, I've always been amazed, whenever I've visited NYC, at just how energy-inefficient many of the buildings are. Single-pane windows, little insulation, baseboard heaters, drafty weatherstripping, the works. I've been there when it's been blazingly hot, and again when it's been bitterly cold, and in both cases the standard solution seems to be to just crank the environmental controls to max. When you split wood in the summer for heat in the winter you quickly develop a respect for how quickly those little inefficiencies add up, and you do something about them. Apparently New Yorkers don't have a similar feedback loop between their effort and their energy usage. Either that, or they're making so much money packaging derivatives their power bills are below the monthly bill noise floor.

New York has rent controls, harsh building codes and corrrupt building inspectors.

When you build a new residential building you know that the first rent you offer will be all that you are likely to get as you are prohibited from raising it and people avoid moving as much as possible to save money on rent via the controls. You also have to bribe the inspectors whether or not you follow the codes so skimping on materials is also common as you are bribing the inspectors anyway you might as well get something for it. As you cannot adjust your prices in the future to cover improvements you build using the simplest and easiest to maintain technologies you can get away with and you do as little to maintain it as possible - maintenance comes directly out of your constantly shrinking profits.

New York landlords are very corrupt because only the corrupt can stomach the crap you have to put up with to be a landlord. Rent controls ensure that there is limited new construction as only the rich can afford to live in a new building, and buildings decay quickly as landlords can't afford to maintain older buildings with long established residents.

People get used to using the Heat and A/C to make up for the deficiencies in the sometimes 100 year old buildings which are uneconomical for the owners to upgrade due to rent controls. As proper construction is expensive to maintain, few new buildings get any but the most basic features unless they are being built for rich people. Crappy living conditions and high heating and cooling costs are a negative externality of the rent controls.

Comment Re:It's all about technology (Score 2) 215

How much of that time is idling in traffic? Electric cars should have a very low draw when idle. It's not so much the duration of your trip that matters but the distance. If you're driving an hour to and from work at the speed limit, then you're not within Melbourne's city limits, you're coming in from the suburbs.

Stop and go eats batteries, having to constantly accelerate to get back up to speed is much more draining than crusing. Crowded cities devour batteries. Distance matters but traffic matters more, an hour in stop and go traffic will wipe your charge and refilling a battery is still not as simple as filling a tank.

Comment Re:The next step is WiFi calling (Score 1) 102

While we are at it, can we make cell phones support WiFi for phone calls?

The phones already have the hardware to do this. People could make calls from places where cell reception sucks but they had Wifi internet. It would also reduce the burden on cell towers as people eliminate landlines and use their cell phones at home, where they probably already have WiFi routers. It also would eliminate the need for those stupid microcells: you could just use your regular wi-fi router for calls without needing to pay for their box.

T-Mobile USA already does this - They call it WiFi calling and it is present on almost all of their internet enabled phones at no extra charge. It is the best reason to buy a T-Mobile branded smartphone rather than an unlocked one like a Nexus if you are going to use T-Mobile prepaid as it is only baked into their branded roms. They do however charge you for minutes or text at the same rate as your regular plan (they treat WiFi calling the same as connecting over a cell tower) if you have an unlimited plan it's free. It works fairly well, and in theory even allows you to connect to their servers from an international WiFi router to make calls to the US without roaming charges.

Comment Re:because we learned nothing from Fukushima (Score 1) 596

Edited Repost of an earlier comment I made

Nuclear power is only expensive because of the coal and enviromental lobbists

http://news.google.com/newspapers?nid=886&dat=19890326&id=dOdSAAAAIBAJ&sjid=KYEDAAAAIBAJ&pg=6879,6110878

Palo Verde Nuclear Generating Station

Inital proposed costs 2.8 Billion

Final Cost 5.8 Billion, 9.3 Billion with Financing added in

1.8 million Manhours wasted

Unreasonable costs attributed to APS management from the post construction independent audit:
50.34 Million

I talked once with a senior security administrator at APS who started out back in the day working security at the construction of that plant and he told me this story.

Due to regulations each contractor had to have the contents of their tool bag inventoried before they were allowed to begin work or leave work and had to log each item used and where it went.

Each item brought into the plant had to be listed on a sheet with each Item getting a line.

Example 1 box of screws
1. cardboard box screws with plastic window 50 count
2. plastic window from box of screws 50 count
3. 1 screw - from box of screws 50 count
4. 1 screw from box of screws 50 count
5. 1 screw from box of screws 50 count

I could go on but you get the point

This was in the days before computers were everywhere so it had to be hand written. At the end of the shift the same procedure was followed and the lists were compared and if there was any discrepency between the two and the contractors work log which recorded each item used and where it was used, a security guard had to accompany the contractor to locate the missing item and recover it.

Initally contractors were put on the clock before they entered security and taken off the clock after they exited security, so there was incentive for workers to pad their hours by bring in unnecessary boxes of screws, and ocassionally leaving an item in the facility so that they could milk overtime. eventually it was sorted out but the contractors constantly found ways to abuse the regulations to justify extra pay.

The plant at the time of the above story had no nuclear material present and the above work area that the contractors were being let into would never be exposed to nuclear material during operation (office building), but the regulation was in place purportedly to reduce the amount of potential nuclear waste by limiting and controlling the amount of material that went into the plant.

Until the regulations governing nuclear power plant construction are rationalized there will be little nuclear plant construction in the US and it will always be expensive and over budget. Nuclear is cheaper than current solar technologies and coal but its the ridiculous unnecessary regulations that drive up the cost. Corner cutting is a logical outcome of excessive and unnecessary regulation. Regulations need to be in place, but they need to make sense too.

Comment Re:The 100% claim is essentially correct (Score 5, Interesting) 409

Nuclear power is only expensive because of the coal and enviromental lobbists

http://news.google.com/newspapers?nid=886&dat=19890326&id=dOdSAAAAIBAJ&sjid=KYEDAAAAIBAJ&pg=6879,6110878

Palo Verde Nuclear Generating Station

Inital proposed costs 2.8 Billion

Final Cost 5.8 Billion, 9.3 Billion with Financing added in

1.8 million Manhours wasted

I talked with a Senior Security employee at APS once who started out back in the day working security at the construction of that plant and he told me this story.

Due to regulations each contractor had to have the contents of their tool bag inventoried before they were allowed to begin work or leave work.

Each item brought into the plant had to be listed on a sheet with each Item getting a line.

Example 1 box of screws
1. cardboard box screws with plastic window 50 count
2. plastic window from box of screws 50 count
3. 1 screw - from box of screws 50 count
4. 1 screw from box of screws 50 count
5. 1 screw from box of screws 50 count

I could go on but you get the point

This was in the days before computers were everywhere so it had to be hand written At the end of the shift the same procedure was followed and the lists were compared and if there was any discrepency between the two and the contractors work log which recorded each item used and where it was used, a security guard had to accompany the contractor to locate the missing item and recover it.

Initally contractors were put on the clock before they entered security and taken off the clock after they exited security, so there was incentive for workers to pad their hours by bring in unnecessary boxes of screws, and ocassionally leaving an item in the facility so that they could milk overtime. eventually it was sorted out but the contractors constantly found ways to abuse the regulations to justify extra pay.

The plant at the time of the above story had no nuclear material present and the above work area that the contractors were being let into would never be exposed to nuclear material during operation (office building), but the regulation was in place purportedly to reduce the amount of potential nuclear waste by limiting and controlling the amount of material that went into the plant.

Until the regulations governing nuclear power plant construction are rationalized there will be almost no nuclear plant construction in the US and it will always be expensive and over budget. Nuclear is cheaper than current solar technologies and coal but its the regulations that drive up the cost.

Comment Re:Too many bodies, too few incentives. (Score 1) 487

But it's ok if we spend a trillion dollars a year on the military?

I believe the GP's point is, if we're going to spend that kind of money, how about spending it on better ways of living that blowing shit up?

Where would we be if we hadn't funded defense in the past, lets see:

Nuclear Power - some of the first nuclear reactors were built as a part of a weapons research program

Computers - original research into computers was funded in a large part by the military for codebreaking

Internet - development largely enabled by military research

Global Positioning System - originally a military system

Cellphones - Enabled by military research into compact and low power radios

Jet Aircraft - Developed by military research

Aircraft in general - benefited from a large amount of military research throughout their entire history

Medicine - The treatment of trauma, infection, disease and various re-constructive surgeries have been greatly improved due to military research.

I could go on, but you get the point. Just about every technology that is used in modern society can trace some part of its lineage to military spending without which it may not have been invented, or invented as quickly or put into general use as the early research was too expensive and had such a poor ROI for anyone but the military to fund.

By all means lets stop funding military research as it has no practical use other than blowing stuff up.

Comment Re:The Duke ain't PC (Score 1) 344

The most any studies have been able to 'prove' is that violent media can be linked to temporary violent thoughts that almost never amount to anything (not even in children).

Albert Bandura and the Bobo Doll experiment was the first to document a link between observing violent behavior and copying it, if you need more proof just look at the number of kids hospitalized from imitating Pro Wrestling and those Jackass shows.

http://en.wikipedia.org/wiki/Bobo_doll_experiment

http://www.youtube.com/watch?v=hHHdovKHDNU&feature=related

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