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I never claimed SpaceX was the first to launch a self-landing rocket, although they are the first to use such a rocket to actually reach orbit and deliver a payload. So please, before God and this vast court of public opinion, please illuminate my lie...

As for your assertion:

Self landing rockets isn't any better than the alternative, which is why no one else continued making them since they were first introduced 40 years ago.

Based on this: SpaceX Falcon 9 Capabilities and Services

and this:

ULA Atlas V costs.

ULA's cost summarized (emphasis mine):

ULA suggests that customers will have much lower insurance and delay costs because of the high Atlas V reliability and schedule certainty, making overall customer costs close to that of using competitors like the SpaceX Falcon 9.

Close. Not equal, not less. Just "close".

Thus, SpaceX's re-usable rockets continue to beat ULA in price, despite ULA's best attempts to cut costs and appear to be more competitive. Re-usability is a major factor in SpaceX's superior price.

I do not believe you are intentionally lying, although your very strong opinion against SpaceX seems to have congealed from a very different and likely much older organic stock. To each their own.

Does the resulting object have desirable mechanical properties, or is it fragile and useless? Most people want to do something useful with their creations.

I don't care if the printer is slow if it can make an object out of Nylon with 30% glass fiber reinforcement. (or even better, Inconel!) That material has good mechanical properties.

are we SURE that we need the collision energies this new collider will give us?

Yes, if you read the reports they give some examples:

"However, several experimental facts do require the extension of the Standard Model and explanations are needed for observations such as the abundance of matter over antimatter, the striking evidence for dark matter and the non-zero neutrino masses. Theoretical issues such as the hierarchy problem, and, more in general, the dynamical origin of the Higgs mechanism, do likewise point to the existence of physics beyond the Standard Model."

Maybe the money would be better spent on bio-medical research, genetic manipulation of food crops, Fusion energy commercialization or space exploration?

Huge amounts of money are already going towards bio-medical research, both by governments and commercial interests: "Globally, in excess of US$200bn is invested each year in biomedical research." link
There is already a multi-billion dollar international research project on fusion energy (see ITER). Fusion energy commercialization in an engineering challenge and not fundamental research and is already be addressed by commercial investment: Tokamak Energy, Commonwealth Fusion Systems, TAE Technologies, General Fusion, Helion Energy, LPPFusion, Proton Scientific and others.
Space exploration is being funded: "global government investment in space exploration totaled $14.6 billion in 2017" link and space exploration is also going commercial, witness SpaceX, Blue Origin, Virgin Galactic, and United Launch Alliance.

It is because I think the is a scam artist who takes public money to enrich himself which convincing all of his followers he is out to save the planet and take them to Mars.

This argument is just ridiculous and stupid. First off Tesla isn't taking any public money. The got a loan a while back (far less than GM incidentally) which they repaid quickly. The tax incentives for purchasing their vehicles don't bring a dime directly to Tesla and frankly probably don't have more than a marginal effect on sales. People who buy $100,000 cars aren't doing it for the tax writeoff and in any case Tesla has burned through the tax rebates available to their customers and yet people are still lining up to buy them. As for SpaceX, yes he launches government satellites and works closely with NASA. So what? So does every other launch company because governments are who launch such devices and NASA is in charge of that sort of business. Furthermore SpaceX has SAVED public money on such launches by lowering cost to orbit. Would you prefer the tax payers pay ULA's jacked up rates instead? Or maybe you would prefer we pay the Russians instead of a US company? SpaceX also has a large launch manifest of non-government clients too which you conveniently ignore. Furthermore please find me a large company that doesn't take full advantage of tax laws and government contracts whenever feasible for them to do so. I think you are being rather selective in your focus on thinking Musk run companies are somehow unusual in that regard.

I also hate cults.

You keep using that word. I do not think it means what you think it means.

I think he is a disgusting human being.

Maybe he is and maybe he isn't but you seem a little fixated. Did Musk pee in your breakfast cereal or something? Let it go dude. Nobody cares if you like him or don't but at least he's doing something creating value in the world. What have you don't that makes you such a moral paragon that we should give a shit about your opinion of Musk?

The heaviest rocket system in the world, not in history. The Saturn V, for all its merit, is not a current player.

That's not how English works... if you say he's the world's tallest man without further qualifications it's generally assumed to mean the tallest man in history. True, the SpaceX page says "The world's most powerful rocket" as a headline but immediately follows up with "Falcon Heavy is the most powerful operational rocket in the world by a factor of two." and that's fair. It's like using "The world's tallest man" as a headline and "At 251 cm, Sultan Kosen is the world's tallest currently living man." as the introduction. But if you're not going to say anything more then it's a bit dishonest...

Falcon 9 Block 5 can put almost 9,000 pounds to MARS Orbit..

https://www.spacex.com/about/c...

That was in short tons, and the stage-1-recoverable weight to LEO would be 22.8 tonnes for block 5.

SpaceX keeps changing the figures here as they upgrade, you can look at the older versions on the Wayback Machine.

While block 4 quoted a 22 tonne mission in expendable mode, block 5 does all missions in recoverable mode and quotes that same weight for a recoverable mission. There is a quote here of Musk on the engine difference: The most important part of Block 5 will be operating the engines at their full thrust capability, which is about 7 or 8% - almost 10% - more than what they currently run at. Note that "full thrust" has been used to refer to increases in thrust twice, with different figures each time.

So, block 5 is about twice the power of the original Falcon 9. I think the quoted weight to LEO might be with no boost-back burn, just ballistic re-entry with a retro and landing burn, as they did for the Telstar 19v the other day (to a substationary orbit).

C'mon. Product life cycle theory.

Falcon 9 is currently the cash cow that finances finalizing development of Falcon Heavy, which is now slowly shifting from question mark to star. BFR is deep in the question mark territory, but before it's completed, FH will be funding it.

Also, SpaceX is barely profitable now, because it spends simply outrageous amount of money on R&D. If they decided to reduce the development tempo to more sane levels it would be swimming in money in no time, it's just earning a fortune in commercial launches and spending it immediately. They have 2 launches per month and they definitely scaled back production of new F9s, they regularly reuse!

SpaceX already runs a trash service. The ISS astronauts put trash into the supply capsule for disposal in the South Pacfic.

It depends on what you mean by "this". This was their first prototype tunnel, working to develop their boring tech (the whole point of Boring Company is to get TBM speeds up and costs down by 1/2 to 1 order of magnitude). It's just a tunnel. They'll also be testing out their first Loop vehicles in it. Since it's just one leg, they'll just go from one end to the other.

Now, as mentioned, this tunnel is just a prototype. It's to be extended to form an LA Loop system, they're getting started on a NY/DC Loop system right now, bidding for a Chicago Loop system, and planning to start a LA/SF Hyperloop system later this year (confirmed by Musk last night - with the interesting addendum that they have a straightforward way to branch in and out of the Hyperloop tunnels to serve smaller cities en route).

Loop is underground PRT (Personal Rapid Transit). Relatively small vehicles take either people or cars. People generally - and cars always - go directly to their destination, rather than on fixed routes. At peak traffic times, passenger capsules get routed to optimal paths with a few stops on each end that group together people going from and to the same general areas (ala Uber Pool). Underground, the main routes are limited access (like highways); there's never any stopping or significant slowing down / speeding up in them. Feeder tunnels branch on and off (again, akin to a highway system rather than a subway system). Control is 100% automated. Access to and from the surface is from numerous small pod elevator shafts rather than fewer, larger stations; the surface footprint is 1-2 parking spaces per shaft (the surface footprint use is justified by how many vehicles it takes off the roads - even when people travel by car, as they're off all of the roads between the start and end of their journey).

Hyperloop is a low-pressure variant of Loop, designed for near-supersonic speeds (and with the potential to operate in environments with higher speeds of sound as well). Several orders of magnitude lower pressure than atmosphere, many orders of magnitude higher pressure than a hard vacuum (and thus several orders of magnitude easier to maintain the reduced pressure, per unit surface area). Some air in the tubes is essential, at least to the "true" Hyperloop proposal (Hyperloop Alpha; there are now lots of other things calling themselves "Hyperloop" that are just maglev vactrains). In the HA design, the vehicles are suspended by air bearings (like an air hockey puck or hard drive platter), which is comparable to maglev in terms of energy losses. The air bearings are fed by a battery powered, water-cooled compressor, which also shunts the air ahead of the vehicle past it (preventing it from building up a high pressure zone ahead of it). Acceleration is provided by short accelerator segments. Wheels propel the craft at low speeds (akin to Loop) and in emergencies. (And to head people off, yes, Thunderf00t the Biochemist-Pretending-To-Be-An-Engineer does not know what he's talking about)

For anyone who's curious as to what's actually proposed in Hyperloop Alpha, and what's been addressed, Link. Note that this document is several years old, so there's plenty of work that's been done since then. This predated Boring Company, so boring costs were estimated at then-current (much higher) rates, and thus boring segments were minimized. They also had to stop the route on the edges of town (like an airport) to save money, as this also predated Loop.

He is a little bit long winded but his math is pretty sane and logic is solid.

No, it isn't.

Don't get your engineering information from a chemist.

PS the infrastructure costs are way more than any highspeed rail

Pulling claims out of a hat is not how you budget; a budget is how you budget.

maintenance of a vacuum

Which is why it is a good thing that Hyperloop does not involve maintaining a vacuum. What people generally refer to as a vacuum - aka, a hard vacuum - is many orders of magnitude more difficult to achieve and maintain than the ~1mbar pressure of Hyperloop. Like on the order of 1e-9 mbar (normal air pressure is close to 1 bar)

Thermal expansion is a huge issue.

Except that it isn't. At all. Engineers deal with thermal expansion every day, and there are numerous ways to handle it, including increasing bend radii (not particularly practical here), expansion joints (Hyperloop Alpha involves one at each endpoint (aka, where the vehicles are moving slowly, on wheels), with the pylons allowing the entire tube to slide freely along its length), or - what HSR generally does - just simply resisting it. Thermal expansion force is just that - a force. It's not some irresistible property of nature; you can resist it with a force running counter to it. HSR generally uses pretensioned rails - that is, they lay them hot, so that when they cool they want to contract - but the contraction is resisted by heavy concrete sleepers anchored well to the ground. That would be a perfectly acceptable approach for Hyperloop as well.

The following is from http://www.spacex.com/falcon-h...

"Only the Saturn V moon rocket, last flown in 1973, delivered more payload to orbit"

Scroll down a little on that page. Graphic has Falcon Heavy, Space Shuttle, Proton M, Delta IV Heavy, Titan IV-B, Ariane 5 ES, Atlas V551, the Japanese H2B, and the Chinese LM3B. As I've noted before, the Heavy is going to be a fine launch vehicle. Unfortunately the zealots are like SJW's, unless blind religious support is given, they try to turn you into an enemy of Spacex.

I'm a fan of Musk, but if you go to their web page, they conveniently omit the Saturn V in their rocket comparison.

The following is from http://www.spacex.com/falcon-h...

"Only the Saturn V moon rocket, last flown in 1973, delivered more payload to orbit"

From the article you linked: the fairing costs $6m? Really?

You are aware that economies of scale are rather limited here right? It's not at all shocking that something like that would cost $6m in the sort of volume SpaceX deals in. Plus they aren't an "inert chuck of metal". Per SpaceX it is composite structure consisting of a 2.5 cm (1 in.) thick aluminum honeycomb core surrounded by carbon fiber face sheet plies (see section 4.3.7). It will require a huge oven for the carbon fiber which you can be sure is expensive and a lot of fancy tooling.

It has to be light, designed to take quite a lot of pressure, shock, and vibration, and deal with temperatures, and it has to separate reliably. These are hard to make and expensive. In some cases the mission requires a custom fairing.

SpaceX plan to send tourists (and possibly also NASA astronauts) around the moon in a Dragon launched by FH. Unless plans have changed, that means they will be man-rating FH.

What a shitty Slashdot summary for such an important event!

Don't bother reading that shitty article. Just go to SpaceX's website directly, where there is video footage. Or look at the SpaceX tweets.

Colonize a new country of citizens that still believe in common sense, rational thought, and intelligent discourse.

That's already a thing.

Or you could wait for the BFR and move to Mars.

How are they faring compared to international competition, like the Japanese and Chinese? Isn't there a risk that the Falcon Heavy will be somewhat outdated before it gets past its first steps?

Well there's two kinds of competition, maximum payload and $/kg to orbit. In the former, there is no competition or rather the competition would be in-orbit assembly like how we built the ISS. The market is rather unclear because since there's no operating super heavy launch vehicle you don't design payloads that require it. The other is $/kg, well if you look at their prices you see Falcon 9 starting at $62M and Falcon Heavy starting at $90M, note that they list max performance and min price so you can't actually divide those to get $/kg to orbit. What you can tell though is that they plan to deliver ~3x the performance for less then 3x the price making the Falcon Heavy cheaper per kg.

That is quite opposite from the SLS and quite possibly other plans on the board where the rocket is so special and launches so rarely that it becomes a billion dollar launch. Like for example the Iridium launches, SpaceX has been launching those 10 at a time on a Falcon 9. Would they do 30 on a Falcon Heavy instead? That's really the key issue for SpaceX, they need business. You can produce a technical marvel like the Saturn V - which would still be unrivaled - but once the moon missions were over nobody could afford it. And then there's the potential for re-usability, with three F9-class first stages to recover they'll be a lot of the cost. If they can be launched not only two times but fives or ten times... the competition shivers.

Not odd at all. It was planned that way.

The SpaceX Iridium 4 Launch was a full thrust launch to get the Iridium satellites in the necessary orbit. When done the 1st stage would not have enough fuel to make a landing so they didn't attempt it. See the official mission overview:

Official mission overview
SpaceX’s Falcon 9 rocket will deliver 10 satellites to low-Earth orbit for Iridium. SpaceX is targeting launch of Iridium-4 from Space Launch Complex 4E (SLC-4E) at Vandenberg Air Force Base in California. The instantaneous launch window is at 5:27 p.m. PST on Friday, December 22 ...

Falcon 9’s first stage for the Iridium-4 mission previously supported the Iridium-2 mission from SLC-4E in June 2017. SpaceX will not attempt to recover Falcon 9’s first stage after launch.

The Press kit for this launch:

http://www.spacex.com/sites/sp...

Mission patch:
http://spacexpatchlist.space/p...

Falcon 9 payload to Mars is 4020kg.
Tesla Model S P100D is 2250kg.
Roadster 2020 will be a bit heavier but not twice as much. Falcon 9 has enough power to send the Roadster to Mars, Musk could choose some better demonstration of Falcon Heavy, such as sending a fleet of 5 Teslas.

Anyone considered just throwing it off planet?

Turn it into glassy lumps and simply throw it off planet with a linear accelerator. Take some gravitational influences into account and you could even aim it at the sun. The sun wouldn't notice the whole planet falling into and we're just talking about a few thousand tons of radioactive waste. (wait until we hear the arguments about polluting the sun. :-)

We would only need to send the high level waste into space.
https://en.wikipedia.org/wiki/...
"A typical large 1000 MWe nuclear reactor produces 25–30 tons of spent fuel per year.[4] If the fuel were reprocessed and vitrified, the waste volume would be only about three cubic meters per year, but the decay heat would be almost the same."

Cost of a launch:
http://www.spacex.com/about/ca...
So to put the high-level waste into a high orbit, it looks like each 1 GW reactor would need one Falcon Heavy, which is about $90,000,000.

Electricity is priced by the kWh.
A 1.GW plant produces a million kWh each hour, or about 8,760,000 kWh a year. So a launch each year would add 10 cents to the price of each kWh.
You can adjust for the average uptime being more like 90% for modern plants.

Are you a NASA employee who knows for a fact that there is absolutely no need for the SLS? It is very unusual for a Rocket to be built that there are no projects ever needed to be launced with it. If a single launch will put 130,000 pounds into LEO, you can bet that there will be payloads approaching that.

And if you want to make 2 60,000 launches of payload with the Falcon Heavy (it will probably be 3 because someone is going to have to assemble the objects in orbit, as well as the payloads being designed to be assembled in orbit, your costs are going to go up, and probablity of success is going to go down.

Are you a Lockheed employee? Because if you are, you just missed Mars. Again.

Falcon Heavy Payload to LEO is 63,800 kg (140,660 lb). Falcon Heavy will have a considerably higher lift capacity than Block 2 of SLS.

As of September 2017, Falcon 9 and Falcon Heavy both are slated to be retired. SpaceX will produce enough of the various cores to satisfy their current launch manifest and then stop building them in favor of producing only BFRs, which are projected to have a 100% reusable payload to LEO capacity of 330,000 lbs and an expendable payload to LEO of 550,000 lbs.

NASA may or may not come up with payloads heavier than an unladen 747 Block 8, but SpaceX already has plans for 6 payloads that will push their own limit.

Why in the hell do all the links go to social media or an ad-spam site? Linking to some schmo's twitter post is just poor form. Cant you just fucking link to the SpaceX site instead of perpetuating this incredibly shitty era we have gotten into where all data must include ads? Why is slashdot sending me over to The Verge when spacex has all the relevant info? Just give us the data, fuck off with your partnerships.

http://www.spacex.com/webcast

You're apparently referring to the (very recent) IAC 2017 presentation, but the (one year older) IAC 2016 presentation didn't seem to mention the cargo option. And since SpaceX is very adventurous in this respect, I wouldn't be surprised if unmanned but "non-cargo" version wasn't the first one to fly, to Mars to boot, not just in their current plans but in reality as well. After all, the "better fail early" still applies at this point of the development cycle, and being able to land on Mars (and to get back) is the ultimate goal, so during an attempt to do that, you reach the intermediate targets such as getting to LEO anyway.

The 29 minutes is the travel time, not the loading time. The loading time is to walk in and sit down. Baggage car might come after one for passengers, its not required to carry both in the same vehicle. Baggage transfer would probably be highly automated and therefore very fast.

I believe that these are tubes between 2 points, and each "point" requires getting up and changing vehicles, like hub airports. Vehicles leave whenever they are ready to leave. There should be no interleaving of vehicles running at speed on the tube and those accelerating to speed.

The target speed is around 700 mph.

Here's how it was originally conceptualized:

http://www.spacex.com/sites/sp...

From the original whtepaper:

"By building a system on pylons, where the tube is not rigidly fixed at any point,
you can dramatically mitigate Earthquake risk and avoid the need for expansion
joints. Tucked away inside each pylon, you could place two adjustable lateral
(XY) dampers and one vertical (Z) damper."

Here's the whitepaper:

http://www.spacex.com/sites/sp...

And no, properly designed vacuum tubes 1) are not particularly prone to accidents (you want to try to make an "accidental" hole in inch-thick steel?)

Firstly, not particularly prone is still miles away from being good enough for a transit system that will be paralyzed by vacuum failure. Secondly, we don't have vacuum tubes of the size and scope proposed by Hyperloop & al in existence, anywhere, let alone above ground or with actual high speed traffic going through them on an hourly basis, so there is in fact no way of knowing the exact failure rate of such tubes. I remind everyone that the test track built by Hyperloop for their pod-design competition earlier this year was less than a mile long and still managed to be the 2nd largest vacuum chamber in existence after NASA's.

Secondly, even if it is true that the failure rate of such tubes is almost nil, that does not account for the fact that it's still possible for anyone with malicious intent to disable the system at any times with ease. As long as it's above ground it won't take much thinking from someone to find a way to puncture the tube, so security-wise it's a nightmare. Even if it's designed safely enough (as one would hope) that vacuum failure will not cause life-threatening danger to passengers, it will certainly cripple the entire route for an extended period of time.

2) do not suffer any form of "propagation" from accidents.

Even so that does not address the other issues. Some of the stuff Hyperloop has currently no answers or numbers for:

1) What is the estimated failure rate?
2) How much does the maintenance of the system cost? (the white paper on Hyperloop by SpaceX includes no maintenance cost estimates whatsoever and the actual building cost estimates themselves are pretty overly optimistic to put it mildly and are lacking on any hard data to back them up).
3) How will physical security of both the tube and the capsules be arranged?

When you consider the fact that without any kind of security the whole system is easily crippled by a single malicious actor, and that with security costs go up as does the travel time, the purported advantages when compared to flying don't seem too good.

I've quoted this article from 2 years ago before on /. when it comes to Hyperloop, but it is still relevant:

The biggest issues are speed and scale. The Hyperloop was pitched as faster and cheaper than alternatives like cars and trains, but even small shifts in those numbers can dramatically change how it stacks up. It's easy to imagine safety concerns limiting Hyperloop speeds to just a fraction of its theoretical top speed or right-of-way issues keeping stations far from urban centers. Would we still be excited about the Hyperloop if a 30-minute trek became a three-hour one? What if it cost $60 billion instead the promised $6 billion? After enough setbacks, it might not be worth developing the technology at all. Those deployment details are life-or-death issues for the Hyperloop, but as long as the tests are focused on small-scale loops, it's not clear we'll ever get answers to them.

SpaceX's latest round of tests doesn't seem likely to change that. The test track is only 5 miles, nowhere near the distance it would take to reach 700 miles per hour. Another test track built by Hyperloop Test Technologies will have the same problem, aiming at a 200mph top speed. For the same reason, these test tracks can’t address the unique safety issues that come with near-supersonic travel. The result is just a tube-powered version of conventional transportation tech like maglev and rail. That doesn't mean that useful work can't be done on this round of test tracks, but it means the central question of the

Go see it for yourself http://www.spacex.com/webcast

if you knew anything about Hyperloop and had read the Alpha document you'd realize that not only is it not "a vacuum transport tube"

I think it's worth quoting the alpha document to get an idea what Musk has in mind.

The approach that I believe would overcome the Kantrowitz limit is to mount an electric compressor fan on the nose of the pod that actively transfers high pressure air from the front to the rear of the vessel. This is like having a pump in the head of the syringe actively relieving pressure.

It would also simultaneously solve another problem, which is how to create a low friction suspension system when traveling at over 700 mph. Wheels don’t work very well at that sort of speed, but a cushion of air does. Air bearings, which use the same basic principle as an air hockey table, have been demonstrated to work at speeds of Mach 1.1 with very low friction. In this case, however, it is the pod that is producing the air cushion, rather than the tube, as it is important to make the tube as low cost and simple as possible.

http://www.spacex.com/sites/sp...

Whether it works and is economically viable... Well, I am not the one with a few successful multi-billion dollar companies that turned the impossible and uneconomical into reality.

http://www.spacex.com/webcast but the landing isn't quite visible because the feed failed for a few seconds.

That's not in the slightest "how they're selling it". Read the design document. To reiterate that which for some inexplicable reason has to be repeated in every thread about Hyperloop: the Hyperloop Alpha design:

  * Is not a pneumatic tube
  * Is not a vacuum train
  * Would not even work in a hard vacuum
  * Is not maglev
  * Is a ground-effect aircraft / air-bearing suspended vehicle in a highly rarified atmosphere, utilizing a battery-powered compressor to shunt the air built up ahead of the vehicle to the suspension and behind the vehicle.

Your failure to read anything about how it works is nobody's fault but your own.

The $422m figure is for a Delta Heavy launch, which makes the comparison with the Falcon 9 laughable

It's actually a valid comparison. The latest versions of the Falcon 9 (full-thrust) can deliver 50,300 lb to LEO and 18,300 lb to GTO (ref)
The Delta IV Heavy can deliver 63,470 lb to LEO and 31,350 lb to GTO (ref).

- it should be compared with a Falcon Heavy launch, which SpaceX ain't giving launch cost figures for yet.

The Falcon Heavy is going to be in a much higher league - 140,700 lb to LEO and 58,900 lb to GTO (ref). And SpaceX has been providing launch costs for the Falcon Heavy for a quite a while ($90M). Falcon Heavy is going steal the little bit of market that remains for the Delta IV Heavy.

of course musk keeps saying that somehow hyperloop would be cheaper

You know, you could actually RTFM (in this case, TFM = Hyperloop Alpha) rather than being bewildered as to why.

The short of it: it's basically a pipeline, so you start with base pipeline costs for the given diameter. Compared to a pipeline:

Advantages:
* Far lower mass loadings
* Does not carry things that could "leak" and contaminate the ground (much easier environmental permitting, less NIMBY)
* Simpler thermal management
* Much lower pumping requirements (just to head this off: it's a mild vacuum, not a hard vacuum. The energy required (and pump sizes) to pump fluids through a pipeline is far more than is required to simply maintain a mild vacuum)
* Usually periodic branch points

Disadvantages:
* Far greater straightness requirements
* Requires an internal orbital polisher
* Periodic emergency exits

Both share infrastructure requirements at their endpoints, just of different kinds, both require a leak detection process, both require regular sensors, both require earthquake protection, etc. In general, however, pipeline construction is not very expensive, even at large diameters, relative to rail construction. The ready-made pipe segments are brought to the site and an orbital welder connects them together.

Versus rail, Hyperloop offers far lower peak mass loadings. This is because (and feel free to do the math yourself, I have) in both cases, the "track" - whether continuously-welded steel rails or orbital-welded pipe, is well lighter than the vehicles on them, but Hyperloop vehicles - being small with frequent launches rather than heavy with infrequent launches - provide far lower mass loadings. The cost of elevating a structure is directly proportional to its peak mass loadings, and hence the order of magnitude lower peak mass loadings translates to an order of magnitude lower elevation cost, as well as smaller cross section pylons which are easier to locate in tight spaces.

This in turn enables the practical location of it in road medians (with proper crash barriers as needed), if you have government buy-in to the concept. Hyperloop Alpha assumes that you will. I have to concur, it's hugely to the advantage of the government to do so, as the government has to spend huge amounts of public money building transportation infrastructure regardless. Road medians are already permitted for far more onerous environmental and noise conditions (road traffic) than Hyperloop would provide, which should make permitting much easier; the only new thing you're introducing is visual, which you have to introduce for any transportation system construction.

Due to the straightness requirements, the system cannot just stay within road medians. Varying bend radii depending on the speed planned for the segment require various deviations from medians. This requires private land acquisition - budgeted at typical rail rates for private land acquisition - and various tall pylons and/or short tunnel segments (budgeted at typical pipeline tunneling rates) where the landscape dictates it in order to maximize curve radii. And yes, they are typical rates, I've crosschecked the numbers in the document, and encourage you to as well.

Now as for the rest as to why it's so much cheaper than rail, they do cheat on that. There's three main ways. The first is simple: it doesn't carry as many people as California's HSR (it's roughly halfway between HSR and air travel on a logarithmic scale in terms of passenger capacity). That's not really a cheat on the per-passenger cost, but it is a cheat on th

Yeah god forbid people spend money on making something real that sometimes creates a whole new industry. I mean look at all those other failures. Damn them for creating businesses that provide gainful employment and research into something new.

I mean there's so many better things to spend money on.

https://en.wikipedia.org/wiki/... says the solar panels have a peak production of 4kW, and in orbit they can probably pull peak production pretty continuously.

And while I couldn't find anything with a quick search on the time between separation and landing, this press release http://www.spacex.com/sites/sp... says it took about two days between launch and docking with the space station, so it might not be completely unreasonable to expect something similar for the return.

As for solar panels versus batteries - if the return flight only takes hours, batteries might indeed be a better solution - except for one thing: You already need the panels for that long flight up, so they're a sunk weight/cost. And you only need enough batteries to supply power before solar panel deployment and during infrequent maneuvers (orbital flight is mostly a matter of coasting between high-efficiency burn points) - the rest of the time you can be in an optimal solar-gain orientation. So the real question is, would adding enough additional batteries to fly back on battery power alone be worth the added weight?

Well that, and the question of whether it's worth the risks and difficulty of performing an EVA to transfer the panels to the ISS, despite the fact that they aren't really designed with ISS requirements in mind anyway, and would only increase the ISS's 120kW peak generating capacity by ~3%, while adding clutter that would complicate more well-conceived future upgrades and other EVAs.

Not really. Although the bulk of the cost of launching is the cost of the Stages the cost of the fuel is not insignificant

Bzzzt, wrong answer

SpaceX's Falcon 9 rocket currently carries a list price of about $54 million. However, the cost of fuel for each flight is only around $200,000 - about 0.4% of the total.

Inform yourself before commenting, it would stop you looking like an idiot. I would suggest you read this first. As from your ill-informed comments you clearly haven't.

as "we will have a man on Mars in 20 years" for the past 50 years. Now it has been extended to infinity. This only trumps up the Mission To Nowhere as everyone loves to talk about Mars because you can defer costs to build real hardware to some other smucks 20 years into the future. Unlike if Moon is the goal then gotta come up with some real money now to build a lander, transfer stage, etc.

But wait, there are some people talking about the Moon besides Spudis and Wingo. Maybe we get some action before we are all dead of old age:
http://www.spacex.com/news/201...
https://www.washingtonpost.com...

And Spudis blog has some interesting comments, http://www.spudislunarresource...

But good luck getting Elon Musk to focus on the practical and eminently desirable target of the Moon. He isn't interested. It's only Mars for Elon.

The SpaceX launch manifest begs to differ. Elon Musk may have Mars as his ultimate goal and be developing the hardware to do it, but in the mean time he is busy launching communication satellites, Iridium satellites, space station resupply, military payloads - anything and everything that people will pay him to launch. If NASA were to foot the bill, he'd be more than happy to land on the Moon.

Or to put it another way, you don't need luck, just money.

People are already looking at solutions to that "problem"
http://www.spacex.com/mars

Is there THAT much shit being sent into space?

Yes. And that's just Spacex, there are a 7 other providers with their own full launch manifests. SpaceFlightNow does a pretty good job tracking upcoming launches.

Some quick searching shows there are about 4500 satellites in orbit, 1500 or them operational. Looks like we are putting about 200+ more per year up there. source So yeah, there is plenty of "shit" to send up there.

It's a thin-walled tube. It doesn't do much constraining at the dynamic forces you're talking about.

It's 20 to 25mm of solid steel. "Thin-walled" is very much a relative thing.

You still have to constrain the tube.

That's what the $2.5 billion in steel-reinforced concrete is for. Also the stringers on the outside of the tube (omitted from all the concept art but mentioned in the text).

Land acquisition and permitting is often the most expensive.

Not solved by Hyperloop.

Solved by Hyperloop insofar as the government of the state of California can be convinced to play ball. The majority of the proposed route is on existing public land. I've said before that this is the reason why Hyperloop won't happen, and not any technical reason. The HSR project allows the Right People to get rich from land speculation. The Hyperloop does not.

But to continue...

In order for it to be a suspension, it needs to absorb the lateral deviations in the track/tube to even out the reaction forces, and it needs to do this at all the required frequencies. At higher and higher speeds, those frequencies correspond to longer and longer track/tube wavelengths over which you have to control or attenuate the deviations.

So design a suspension system. And don't forget, you have quite a lot of room to play around in. Per the document, the capsule only occupies 36% of the cross-sectional area of the tube. People have this persistent notion that the Hyperloop capsule is jammed into its tube like the carrier in a bank's pneumatic system. It's not. There's plenty of room for as sophisticated a suspension system as necessary.

Viaduct costs are minimized by a key design feature of Hyperloop - minimizing peak loadings by having frequent, small vehicle launches rather than infrequent, large vehicle launches. Viaduct costs tend to track their peak loading.

Why don't trains already do this?

Because trains haul freight, everywhere in the world. Passengers are an afterthought, and an ill-considered afterthought at that.

As for land acquisition, the costs in Hyperloop Alpha are kept down by a combination of design and cheating. As per design, it's designed to be small enough to fit elevated into highway medians, with the low peak loadings, making overhead suspension an affordable option. Such places are state land, and already permitted for far more environmentally harmful activity (road traffic).

Why don't trains already do this?

Because trains haul freight. It doesn't have to get there quickly, but when it does, there sure is a lot of it.

the Hyperloop Alpha document (at least the one I read on the Space-X website) "highly addresses" precisely nothing. It's envelope calcs and napkin sketches.

Well no, it's more than back-of-the-envelope calculations. Somebody went to the trouble of putting together a solid model of the tube and the pylons and running it through the simulator. But yes, the document is not sufficient for some guy with a hammer to go out and start slapping one up. It's a proposal. It's been sanity-checked fairly well, by people who understand just as much about static and dynamic loads as you do, and it's been mathematically demonstrated to be not insane. No, the capsule suspension system has not been worked out. Nor has the capsule door seal, which must stay air-tight in the face of dozens of unsealings and resealings a day, not to mention foot traffic. Nor has the exact nature of the system that ties the tube to a pylon been worked out.

But none of these things are physical or financial impossibilities. Analogs can be found in existing products and structures.

You can also read SpaceX's status updates about it here: http://www.spacex.com/news/201...

Musk is a Space Nutter.

You throw around the phrase "space nutter" as if that actually means something every time an article about Musk is posted. Let it go. If you want to make an evidence based case that going to Mars is not possible then fine. Ad-hominem attacks do not in any way bolster your case. They just make you look like a jerk.

There is no way ANYONE is going to Mars.

If you want to claim that people aren't going to be on Mars in the near future I would agree with you. Any such mission is going to take a while before it happens. If you are going to claim that it is categorically impossible that humans will ever set foot on Mars then you have no evidence to back you up. Present some actual and irrefutable evidence that putting humans on Mars is irreducibly impossible or shut up about it. So far your argument consists of calling anyone who is interested in solving the problem a "space nutter".

The trip alone would kill you with radiation.

And you of course have irrefutable proof not available to the rest of us that there is no possible way to mitigate that problem? Rhetorical question because of course since you don't and we know you don't. It's a known problem with numerous potential solutions. We aren't going to Mars tomorrow. If/when we do try to go it will be among the engineering challenges we face and one of the risks along the way. There is no evidence that it is a problem without any feasible solution given enough research and funding.

This guy is a scam artist and is trying to get taxpayer money to fund it, so he can siphon it off to pay for his other projects.

I'm not sure you know what the word means. Building at last count 4 successful and industry changing companies, three of which have nothing to do with space nor rely on any direct tax dollars, is a peculiar means of scamming people out of tax dollars. Furthermore most of the SpaceX mission list has private companies as clients as of today so basically no tax dollars are at work there either. Additionally SpaceX is actually SAVING tax dollars by reducing the cost to orbit over what NASA can do themselves. You might want to actually use some facts in your argument at some point. They tend to help.

SpaceX will be streaming Elon Musk's presentation live on their website.

What? They launch for several countries and companies. http://www.spacex.com/missions

Your analogies are total BS, and i do know what I'm talking about.

Until you've actually read the proposal, which thusfar you have demonstrably not read, then you don't know one iota about the subject, and I'm not going to read another word you write. For the simple reason that I'm not going to waste my time arguing with a person about a subject that they can't be bothered to learn even the most fundamental aspects of..

Let me know when you've actually read it in its entirity, then get back here and we can talk.

The anomaly originated around the upper stage oxygen tank and occurred during propellant loading of the vehicle.

They don't go so far as to say that it was a pad issue separate from the Falcon. This could still be a problem with the rocket or with external equipment.

The first stage and the second stage disconnect.
The first stage flips around end to end, and makes a burn to kill most of its velocity.
Then as it is entering the thicker parts of the atmosphere and it would be destroyed by drag and heating otherwise, rapidly slows at high G using the engines to around mach 1, and turns the engines off.
It is at this time steering using fins attached to the top of the rocket.
Once it gets ~10-20 seconds before landing, it lights an engine or three (details vary) and uses the thrust from these vectored in order to precisely land on the barge (along with the fins in the initial portion).

http://www.spacex.com/sites/sp... is a nice diagram.

This payload was light enough, and the upgraded F9 grunty enough, that it could do it, but larger payloads will require an ocean landing.

A barge landing can use the atmosphere for braking, but that means that you re-enter halfway across the Atlantic. Returning to the launch site takes a honking great boost-back maneuver. The booster accelerated to 6000 km/h (1 mile per second) before staging. While some part of that is vertical and gravity will help, for orbital insertion the majority is lateral, and the booster has to cancel all of that velocity propulsively before it can start backtracking to the launch site.

The fundamental job of a rocket is to supply kinetic energy to a payload. Energy consumed in boost-back is not delivered to the payload.

As Elon Musk explains, return to launch site is much more expensive than return to barge. F9 can deliver 300 GJ of energy to the second stage and return to a barge. Or it can deliver 120 GJ to the second stage and return to the launch site. That's 40%. Return to launch site is throwing away 60% of the booster.

Notice how much they talked about the performance increases. Higher engine thrust, densified LOX to fix more fuel into the first stage, a stretched second stage. Even though the net payload mass is one third of the Dragon capsule on CRS-7.

(Dragon has 6000 kg payload capacity, plus the pressurized capsule and orbital maneuvering system isn't light. 12×172 kg of Orbcomm satellites is 2064 kg, plus a fairing and deployment bus.)

Although it's >90% of the weight, the cost of kerlox rocket fuel is so tiny compared to the rest that it's worth burning more fuel for a higher-probability of recovery. But not all payloads give you that option.