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Suborbital Spaceflight Picks Up Speed

samzenpus posted about 7 months ago | from the major-tom dept.

Space 51

RocketAcademy writes "The race to develop low-cost, suborbital spaceflight is heating up. On Thursday, Virgin Galactic's SpaceShip Two successfully completed its second powered test flight, reaching a speed of Mach 1.4 and an altitude of 69,000 feet. Meanwhile, XCOR Aerospace has begun posting daily reports on the progress of its Lynx spaceplane, which is expected to begin flight tests sometime around the end of this year. This means one of both companies are likely to begin commercial service by the end of next year. XCOR still plans to move its headquarters to Midland, Texas later this year, but Midland may not be the only suborbital spaceport in the Lone Star state. On Wednesday, the Houston Airport System revealed renderings of its proposed spaceport at Ellington Airport, near Johnson Space Center just south of Houston. Citizens in Space (also based in Texas) has begun training five citizen astronauts to fly as payload operators on the XCOR Lynx and evaluating biomedical sensors for use on the flights. Details of those astronaut activities were also released this week."

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Summary can't make up it's mind (4, Funny)

MrNemesis (587188) | about 7 months ago | (#44773519)

Suborbital Spaceflight Picks Up Speed

...then it'd be orbital spaceflight.

suborbital spaceflight is heating up

...and now it's crashing back down through the atmosphere.

Sheesh, this is elementary physics, make your mind up editors!

Layman here... (1)

cablepokerface (718716) | about 7 months ago | (#44773609)

Seems to me that a plane flying into space and land by itself should be the real race shouldn't it? This doesn't seem very low cost (relatively maybe). Is this a necessary step engineering-wise?

Re:Layman here... (3, Insightful)

confused one (671304) | about 7 months ago | (#44773801)

It's very costly. You have to carry all that weight out of the gravity well and into orbit, up to orbital speeds (~17,000 mph), then get it back down safely (requiring a very expensive thermal protection system). It's why the Shuttle was so expensive to operate and why no one else is doing it that way.

Re:Layman here... (1)

Xicor (2738029) | about 7 months ago | (#44774537)

there wont really be any real space travel until we find some way to get out of the atmosphere without spending billions of dollars on fuel. there are many new prototypes as far as space propulsion go, that are cheap to produce and cheap to utilize, but they just dont have the power necessary to get out of earth's atmosphere. in all the movies, they solve this by taking high powered shuttles to an orbital space station that can hold shuttles and space ships, and really, this is the only feasable solution at this point, it just has to get done

Re:Layman here... (2)

h4rr4r (612664) | about 7 months ago | (#44774881)

Billions on fuel?
Kerosene and LOX are not that expensive. There are a lot of other costs than fuel. Getting out of the atmosphere is easy and relatively cheap, getting up to orbital speed is a whole other ballgame.

Re:Layman here... (2)

nitehawk214 (222219) | about 7 months ago | (#44776041)

Billions on fuel?
Kerosene and LOX are not that expensive. There are a lot of other costs than fuel. Getting out of the atmosphere is easy and relatively cheap, getting up to orbital speed is a whole other ballgame.

But when you throw away the fuel tank and rocket motor every time you fly... it is very expensive.

Car analogy time: Rocketry is like buying a new car and wrecking it every time you want to travel to the next city.

Re:Layman here... (1)

h4rr4r (612664) | about 7 months ago | (#44777467)

Those are expensive, but they are not fuel.

Re:Layman here... (1)

Xicor (2738029) | about 7 months ago | (#44778579)

even the rocket fuel is so expensive you probably cant afford it

Re:Layman here... (1)

Teancum (67324) | about 7 months ago | (#44778941)

even the rocket fuel is so expensive you probably cant afford it

Not really. For the Space Shuttle launches, the catering budget for the press corps covering the launches was usually more than the cost of the actual fuel that went into that rocket. The cost for the amount of rocket fuel needed to get somebody into orbit is about a thousand dollars or so (or at least that order of magnitude). Essentially the price of a first-class ticket on a trans-continental airliner. In order to get to Mars, round trip, (or just about anywhere else in the Solar System) you need about 4x that fuel... and not much more.

That is clearly something affordable by anybody in a 1st world country... and you wouldn't even need to mortgage your house. Yes, you could even pay for this on a minimum wage salary working part-time but perhaps making a few sacrifices and doing without luxuries... but still something that could be done. You'd be surprised at how cheap you can live if you care. I'm not saying that people from Somalia or Ethiopia are going to be able to afford this, but I would say that likely a majority of the people from around the world could most certainly afford the rocket fuel needed to get into space and actually do stuff once you get up there.

The huge expense for traveling into space is the cost of the vehicle itself, and the fact that it is amortized over exactly one flight each time, not to mention that the launch pad costs are usually covered only by a dozen or so flights as well. On top of that, when you have a full-time and permanent army of about 30k-100k people involved with the prep-work and deployment of that vehicle on every launch (which was true even for the "reusable" Space Shuttle), those salaries start to add up real quick. For the Apollo flights, there were typically not just one but two carrier task forces that were assigned to perform search & rescue (in the event of a mishap) or recovery on every flight including two weeks prior to each flight and even a week following the flight. There is a reason why it cost about a billion dollars for each launch.

No, it isn't the fuel that is the problem. Much cheaper launches can certainly happen and there is at least the possibility that travel into space can be affordable for mere mortals. If you can make the spacecraft reusable and only needing a dozen or so people on the launch pad in order to "turn around" the vehicle from a landing to launch, it would most certainly be affordable. That is the reason why you can afford to travel by air to most places around the world... because British Airways doesn't throw away their aircraft after each flight.

Re:Layman here... (1)

khallow (566160) | about 7 months ago | (#44779333)

there wont really be any real space travel until we find some way to get out of the atmosphere without spending billions of dollars on fuel.

Currently, we spend on propellant at worst hundreds of dollars per kilogram of what gets into space. A billion dollars of propellant covers several thousand tons of stuff, up to around ten thousand tons for diesel/LOX burning rockets like the Proton or Falcon 9.

Re:Layman here... (1)

cjameshuff (624879) | about 7 months ago | (#44779529)

In fact, 1 billion dollars would fuel around 5000 Falcon 9 launches, each lifting 13 metric tons of payload to LEO, for 65000 metric tons total. For the Falcon 9 (one of the lowest cost launchers), propellant is about 0.4% of the launch cost.

The real costs are in the hardware and in operations. The problem is that there really hasn't been a huge amount of incentive to reduce costs. Especially in NASA's launcher programs, where things like Constellation and the SLS are specifically intended to keep Shuttle personnel employed and funds going to the important Congressional districts. This is just not an approach that will reduce costs.

The COTS effort is shaking things up a bit. SpaceX's prices are a lot lower than the competition's, and they are working on recovery and reuse of as much of the vehicle as is economical.

Re:Layman here... (2)

h4rr4r (612664) | about 7 months ago | (#44774865)

I think a lot of this space plane stuff in the minds of civilians misses that last point. When you don't understand what is really happening you might well assume just getting high up is enough.

Turns out though it is fine for suborbital space flight, which is great for tourists.

Re:Layman here... (0)

Anonymous Coward | about 7 months ago | (#44773831)

The Air Force thought so in the 1960's when they designed the X-20... which looks an awful lot like the Lynx illustration. Rockets were easier and quicker to get right, so Mercury got funding and the spaceplanes didn't. Now that rocket motors are commodity items and high-performance composites are commonplace, why not revisit spaceplanes?

Re:Layman here... (2)

istartedi (132515) | about 7 months ago | (#44774791)

a plane flying into space and land by itself should be the real race shouldn't it?

Sometimes the sci-fi vision is prescient. Sometimes it isn't. A flip-phone looks like the original Star Trek communicator. Yay! The new phones don't. Oh well. The 3.5 floppy looked just like the storage used on the original series also. The floppy also came and went.

The Space Shuttle was the closest we've come yet to the sci-fi vision of the space plane to which you refer. It still had to drop a lot of stuff before reaching orbit. I've always wondered to what extent our problems there came because we allowed ourselves to be lead astray by the sci-fi vision. Meanwhile, the Russians continued to perfect un-glamorous but relatively reliable rockets and long duration space flight.

The sci-fi vision is a double-edged sword. It inspires us and stimulates ideas. It can lead us astray if we obsess over achieving objectives that match it in some particular way.

Re:Layman here... (1)

Teancum (67324) | about 7 months ago | (#44779093)

The Space Shuttle was the closest we've come yet to the sci-fi vision of the space plane to which you refer. It still had to drop a lot of stuff before reaching orbit. I've always wondered to what extent our problems there came because we allowed ourselves to be lead astray by the sci-fi vision. Meanwhile, the Russians continued to perfect un-glamorous but relatively reliable rockets and long duration space flight.

The problem with the Space Shuttle is that it was a 1st generation prototype. Not only was it a prototype that never really evolve into subsequent generations, it was a lousy design in the first place which had explicit design constraints to meet missions that were rarely or even never actually used. By far and away the best possible use for the Space Shuttle, to give an example, is to bring heavy objects down from an orbital flight profile back to the Earth. I think that was done precisely twice in the roughly 150+ flights that were made. It was also designed to fly from Vandenberg AFB in a polar orbital configuration.... something it never accomplished at all in practice. Other design compromises were made which basically made the Shuttle into a bastard child of ideas and clearly made by a committee with political motivations other than actually trying to get people into space... and certainly not to make it cheaper to go into space.

I wouldn't write off the concept of the Shuttle, and clearly the fact that it flew at all should be a reason to at least consider some of the aspects of the Space Shuttle for future spacecraft designs. Jeff Greason of XCOR has used some (not all) of the ideas that were developed for the Space Shuttle in the design of the Lynx. None the less, there are reasons why the Shuttle design ought to be full of warnings as well and mistakes that shouldn't be made.

I'll also note that the real innovation in rocket design is happening in America... but not through NASA contracts.

Re:Layman here... (1)

plover (150551) | about 7 months ago | (#44779237)

So assuming the Star Trek communicators inspired flip phones, carry that one out the rest of the way. They made us think of communication systems with tiny electronics and no wires. Those are still the identifying characteristics of cell phones regardless of the form factor. Uhura had her non-Bluetooth earpiece, and now we have Jawbones. Yeoman Rand had Kirk signing a tablet, and while William Shatner could have signed on a Palm Pilot fifteen years ago, you can do even better on your iPad Mini or your Kindle HD today.

So here we are, still 250 years away from the future portrayed in the show (and 46 years after the sci-fi tech was shown), and we already have fourth or fifth generations of some of their tools. I am not disappointed that someone obsessed on achieving those technologies exactly - I celebrate that we've surpassed them.

What we really need are more inventors inspired by the science fiction writers, and more science fiction writers creating more ideas. It's even OK if we try to turn them all into reality, yet chase down a lot of dead ends. Most are no doubt doomed to languish forever on untended wiki pages, while others will be destined to become the ubiquitous tech of tomorrow.

Re:Layman here... (3, Interesting)

joe_frisch (1366229) | about 7 months ago | (#44775001)

A single stage to orbit vehicle is very difficult. The amount of fuel a rocket needs to carry increases exponentially with the ratio of the required velocity change to the exhaust velocity. The options are very limited.

Solid propellants have much too low exhaust velocity for this to be workable.

Kerosene / Oxygen is a typical rocket propellant, but the exhaust velocity is low enough that a single stage to orbit would require an unreasonable ratio of fuel to rocket mass. I don't remember any design concepts for kerosene / O2 rockets for single stage to orbit.

Hydrogen / Oxygen has higher exhaust velocity but liquid hydrogen is very low density so the fuel tanks become enormous, and heavy. There have been design studies for Hydrogen / oxygen single stage to orbit, but it doesn't look very practical - you basically have an enormous flying fuel tank.

The more exotic chemical fuel mixes don't improve things a lot and are too toxic and expensive for atmospheric use. Fluorine / Beryllium / Hydrogen tri-propellant has good specific impulse but is insanely deadly in multiple ways.

Nuclear thermal (like NERVA) could probably do it, but people are understandably unwilling to put 100GW class nuclear reactors in rockets and launch them.

Airbreathing rockets (like ram-jets / scram jets) don't need to carry their own oxidizer and in principal do much better. The problem is that hypersonic ram-jets are very difficult to build and wind up heavy and inefficient. (Mach ~8, only 1/3 of orbital speed, 1/10 orbital energy) is the highest speed ramjet that I am aware of. For various fundamental reasons you expect the performance of ramjets to drop with velocity. Since ramjets also don't work at low speeds, you wind up needing a 3 stage rocket: conventional, scram-jet, conventional, and it ends up not having any advantage over just conventional rockets.

The basic technology for getting things into orbit hasn't changed in over 50 years, and really isn't likely to change - just no clear path. The best approach is probably what Space-X is doing, optimizing the design, and working to make each of the stages recoverable to reduce costs.

The "tourist" sub-orbital rockets don't seem to me to be developing technologies that are applicable to orbital flights. They may attract a few people who are willing to spend $100K for a few minutes of zero-G, but I suspect that most wealthy thrill-seekers will quickly find that a ride in a MIG-29 is a lot more fun and less expensive.

Re:Layman here... (0)

Anonymous Coward | about 7 months ago | (#44776511)

A single stage to orbit vehicle is very difficult.

Not so difficult as all that, actually. The original Atlas was essentially single stage to orbit, except that it jettisoned it's two outboard engines (but no tankage) when it no longer needed them. It could probably have taken them to orbit if it weren't carrying payload. As a thought exercise, replace the 5 J-2 engines on the Saturn V second stage with a single SSME (and move the LOX/LH2 bulkhead to accomodate the different mix ratio) and the thing could do ground to orbit.

Of course, none of the above configurations would survive reentry and landing, so aren't reusable ... which kind of defeats the purpose of SSTO. But it's proof of concept. We just need to be a bit smarter about materials and systems integration, ie designing parts to serve multiple purposes to save weight, or propellant mixtures optimized for weight taking into account tank mass (which rules out LH2 which has such low density it requires huge tanks).

Re:Layman here... (1)

joe_frisch (1366229) | about 7 months ago | (#44797709)

I was considering a SSTO to include return, since as you say it doesn't do much good to get the entire rocket into orbit, but then need to throw it away.

I don't think it is completely impossible, but so far it hasn't been practical. People have worked VERY hard on materials for spacecraft, and they do adjust the H2, LOX mixture to include tank weight (and engine temperatures). One indication of how well launch vehicles are optimized is how little the technology has changed in 40 years. The LEO payload to launch weight ration of a saturn V was 24:1 to 30:1 (sources vary). Its 37:1 for an Ariane 5 and 32:1 for a Falcon 9.

Re:Layman here... (0)

Anonymous Coward | about 7 months ago | (#44801315)

Aerospikes help as well. The Linear Aerospike was designed at Stennis for use in the x33 and the engines did very well in testing. The plans for the craft were scuttled in 93 because of political shenannigans and the fact that composites tech just weren't up to snuff until about 2010 with the 787. A traditional rocket using Aerospikes could very well go single stage to orbit, or at the very least two stage with each stage reusable.

Re:Layman here... (1)

sahonen (680948) | about 7 months ago | (#44794721)

What do you think of SABRE?

Re:Layman here... (1)

joe_frisch (1366229) | about 7 months ago | (#44797619)

The concept of a combined air-breathing engine / rocket is reasonable - and has be around since the 60s. One very serious technical difficulty is the need to slow the input air to sub-sonic speeds without creating too much drag. Their design airbreathign speed of about mach 5 is probably limited by this.

Then the question is whether carrying all of the extra weight of the more complex engine into orbit loses more energy than you gain from using air-breathing to get to mach 5.

It might be a better fit as an engine for a first stage of a 2-stage reusable. If you are only accelerating the heavier engine to say mach 10, then staging it might be a win. Maybe not.

Still not holding my breath. (0)

Anonymous Coward | about 7 months ago | (#44773641)

SpaceShipOne finished flights in 2004, 9 years ago. The original schedule had commercial operations beginning in 2006, 7 years ago.

Wake me up when they launch the first commercial flight. I'm not expecting it this decade.

The ad.. (0)

Anonymous Coward | about 7 months ago | (#44773667)

HI, I'm Sarah Brighman, let's talk about suborbital spaceflights..

Re:The ad.. (0)

Anonymous Coward | about 7 months ago | (#44777149)

HI, I'm Sarah Brighman, let's talk about suborbital spaceflights..

If you want your heart back, you gotta get it back from the trooper who stole it ;)

Suborbital is not Orbital (1)

confused one (671304) | about 7 months ago | (#44773851)

It's a tourist trap. They're not entering orbit, not even close. Wake me when SpaceX and Boeing get manned commercial orbital flights off the ground.

Re:Suborbital is not Orbital (0)

cusco (717999) | about 7 months ago | (#44775325)

Hooray for Virgin Galactic! They've reproduced the flight of the Bell X-1 of the late 1940s. Impressive, I'm sure they'll be building their orbital hotel any day now.

Re:Suborbital is not Orbital (0)

Anonymous Coward | about 7 months ago | (#44775739)

They've already reproduced the NAA X-15 of the 1960's. This is a shakedown flight.

Games as a teaching tool (5, Interesting)

jandrese (485) | about 7 months ago | (#44773879)

Play around with Kerbal Space Program and you realize just how big the gulf is between suborbital and orbital flights. Getting enough boom to get yourself up to 100km is trivial. You really appreciate the difference in design when you're doing it yourself and seeing just how much more boom it takes to achieve orbit.

Re:Games as a teaching tool (1)

Alioth (221270) | about 7 months ago | (#44774817)

...and that's with KSP making it far easier to get to orbit too (2 km/s orbital speed rather than 8 km/s as for Earth, and a planet whose atmosphere ends at 70km, with 1/10th of the radius of Earth)

Re:Games as a teaching tool (1)

jandrese (485) | about 7 months ago | (#44776725)

To be fair though, KSP rockets are firecrackers compared to real life launch vehicles. One point of comparision is the "big" SRBs. The KSP ones produce about 2% of the total thrust of the old Shuttle SRBs. If you look at the total thrust of KSP's big Mainsail engines vs. the Apollo program's F-1 engines the differences are even bigger. KSP engines are more efficient in terms of lbs. of thrust per lb of propellant though.

Re:Games as a teaching tool (0)

Anonymous Coward | about 7 months ago | (#44801353)

KSP tanks are tiny though. the jumbo 64 (biggest tank you can get), is about as wide as a car lane. Though this makes sense since a kerbal is only about 45 centimeters tall.

Re:Games as a teaching tool (0)

Anonymous Coward | about 7 months ago | (#44779091)

Play around with Kerbal Space Program and you realize just how big the gulf is between suborbital and orbital flights. Getting enough boom to get yourself up to 100km is trivial. You really appreciate the difference in design when you're doing it yourself and seeing just how much more boom it takes to achieve orbit.

If you need a game to tell you that then aerospace engineering might not be for you.

Those terrible renders... (1)

jordanjay29 (1298951) | about 7 months ago | (#44774183)

Anyone else take a look at those renders for Ellington Airport? I just love how the roads and platforms make no engineering sense whatsoever.

I must be in the wrong career field. I should have become an architect so I can design shit that makes no sense.

Re:Those terrible renders... (2)

plover (150551) | about 7 months ago | (#44779045)

Anyone else take a look at those renders for Ellington Airport? I just love how the roads and platforms make no engineering sense whatsoever.

Well, you need customers at your spaceport, so therefore you need roads. If you build them, they will fly. Obviously, you'll have full commuter ships leaving for space every 30 minutes, so you'll need four lanes of freeway to deliver all those people, and they're all going to want to park next to the building, so make sure you have a really big terminal. A giant grass bridge over the freeway lets people wander aimlessly beneath the glory of your rocket-filled sky, so make sure to include one of those. And monorails should whiz by giving all the locals a chance to see the future you're providing them as they roll on to their uneventful days ahead.

A spaceport obviously can't serve anybody without support staff, like ticket agents, travel agents, baggage handlers, TSA gropers, insurance salesmen, USO staffers, McFood operators, cart drivers, taxi stand starters, and telephone sanitizers. So you're going to need a lot of lodging to house these people. And they're going to want to live in an interesting place, so stick an F15 on a metal post and now it's an interactive park-museum, fun for the whole family (for at least an hour on a Saturday.)

Now think about all those space customers. If you've been out orbiting hard all day, you're obviously going to want to crash in a nice five star hotel ("crash", "five STARS" - I'm using spaceflight metaphors there, did you get 'em?) at the end of the day. That means you need golfing and pubs and water hazards placed next to a tall building.

See? You're pretty close to an architect already. Just add crowds of people who have no reason to be there whatsoever, and sprinkle liberally with immature trees, and that's practically a bachelor's degree right there.

Suborbital just isn't that hard (1)

Nimey (114278) | about 7 months ago | (#44774365)

KSP tells us that all you need for a suborbital flight is a fuel tank, a medium-sized liquid-fuel engine, and a fear-crazed Kerbal. What's the hold-up?

Re:Suborbital just isn't that hard (0)

Anonymous Coward | about 7 months ago | (#44774457)

These are spaceplanes. All KSP has taught me about spaceplanes is that they always veer off the runway and explode for no apparent reason.

Re:Suborbital just isn't that hard (0)

Anonymous Coward | about 7 months ago | (#44775627)

These are spaceplanes. All KSP has taught me about spaceplanes is that they always veer off the runway and explode for hilarious entertainment purposes.

Fixed.

Re:Suborbital just isn't that hard (0)

Anonymous Coward | about 7 months ago | (#44776535)

What's the hold-up?

Alas, a severe shortage of real world Kerbals, fear-crazed or otherwise.

werent they supposed to start flights in 2010? (1)

peter303 (12292) | about 7 months ago | (#44774493)

I'd rather they'd be safe than rush. Plus a major recession intervened. I heard a talk from a person who took the Virgn Galactic boot camp in 2011. That is supposed prepared you for the high-G ride and weed out doubters.

XCOR is taking passengers (0)

Anonymous Coward | about 7 months ago | (#44774539)

I should know, I work with a guy who has a ticket to be on one of their first flights.

Re: XCOR is taking passengers (0)

Anonymous Coward | about 7 months ago | (#44776279)

And I know a guy who knows a guy who's actually piloting the ship.

Oh, I like this make-believe stuff.

Re: XCOR is taking passengers (0)

Anonymous Coward | about 7 months ago | (#44779109)

Oh, I like this make-believe stuff.

You still think the Apollo missions happened in a Burbank sound stage?

cool (0)

Anonymous Coward | about 7 months ago | (#44777205)

one step closer to getting off this rock.

It's my understanding... (1)

canadiannomad (1745008) | about 7 months ago | (#44778911)

Ok I remember reading that Virgin Galactic is expecting its first passenger flight this year... Christmas Day...

Here it is:
Virgin Galactic first flight expected in 2013 [wired.co.uk]
Richard Branson: first Virgin Galactic flight on Christmas Day [ausbt.com.au]
Virgin Galactic to launch on Christmas [macombdaily.com]
And he plans to take his kids:
Our 500th Astronaut [virgingalactic.com]

I'm sure it could all fall through, or some regulator will pop their head in, but my bets are with the exuberant billionaire.

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