SpaceShipThree to be Orbital Spacecraft

FleaPlus writes "The president of spaceflight company Virgin Galactic has recently stated that if the upcoming suborbital service with SpaceShipTwo is successful, the follow-up SpaceShipThree will be an orbital craft. Although orbital spaceflights would be much longer and could potentially dock with orbital space stations, they are also considerably more difficult than suborbital spaceflights. Other private firms working on orbital spaceflight (and potentially in the running for Robert Bigelow's $50 million America's Space Prize for orbital flight) include t/Space and SpaceX."

Comments

Only assuming thye use the same design

[arevos]

I suspect that the engineers involved in Vigin Galactic are not complete morons, and might possibly know a little bit about high altitude flight and rocket engines. Perhaps even more than you do, surprising as that may seem.

If they set about designing an orbital craft, I'd hazard a guess and say that they wouldn't use an engine design that is known not to work. Likely as not, they'd use a different engine design that is known to work.

Re:Only assuming thye use the same design

[Capt'n Hector]

The grandparent has a point though. A scalable SSTO (single stage to orbit) engine is a holy grail of sorts because it must provide lift in various situations while being near maximally efficient the whole time. Nasa (and everybody else) solved this by using multiple engines: liquid main engines, solid boosters for the shuttle). Now perhaps SC has found an engine that will get them to orbit, who knows, but it's a bigger problem than you might think. Fuel is an issue:

Fuels that are used in space must carry their own oxygen, but when going at high speeds in the earth's atmosphere, why not make like a jet engine and get oxygen from the atmosphere? Perhaps there could be two fuels, one for use in the atmosphere and one for use in space. The engine would start using one, then as pressure dropped would slowly switch to the other. But of course with an air intake that must work from zero to hypersonic speeds, you run into some pretty nasty physics in designing the thing. End result is you end up with a non-constant flow of oxygen to your engine, no matter how well you design your system. Thus the engine must be designed with this tolerance in mind.

So, anyone trying this: good luck!

Here's why

[RoverDaddy]

1. Because I know the orbital flight will cost 10x the suborbital and I'm not quite rich enough for that.

2. Because I'll be dead before they get the orbital vehicle ready for commercial passengers.

Re:PR bullshit

[dabigpaybackski]

IANARS, but I think Rutan ought to start thinking really big and start a privately-funded consortium to build a spaceport down in Ecuador. They build a launch ramp on the western slope of a mountain, as the Skyramp people are proposing, and rapidly put all of their competitors out of business.

Then, when the materials tech becomes practical, they build a space elevator on the very same site. Makes perfect sense; at that point, they have the name and a shitload of capital to make it happen. Taxpayers have spent enough on incremental baby steps and aerospace subsidies.

May dreams such as these take wing and I'd be happy just to watch: (link)

Re:PR bullshit

[Teancum]

I have to agree that I prefer to buy products from (and work for) companies that tend to keep their PR under wraps until they actually have something to show for what they have been spending all of their R&D budgets. I have done too many projects that I call "design by press release", where my boss tells me what the product is supposed to do by sending out the press release, and they I have to try and shoehorn the project to meet those expectations (including customer expectations). It is never a good thing.

In the computer software industry, you can sometimes get away with that sort of mentality, but in aviation and especially rocketry I would say that is an absolute mistake. If I were running an aerospace company there is only one way I would dare make that sort of press release, and that would be if I already had the designs "on the drawing board" and had already proven most of the major technological hurdles (at least from a test lab viewpoint). Obviously Scaled Composites hasn't sent anything up besides SS1, and you (as well as others) are correct that SS1 by itself simply won't scale up to orbital velocities without some very substantial structural and raw materials changes. Essentially a whole new spacecraft from the ground up.

SpaceX I think has at least been doing the right thing, and they got a bunch of real rocket scientists that know their stuff. They will get to orbit (unmanned), and if their Falcon I is successful, the Falcon V has a very good chance of success. The Falcon V is also a "next generation" spacecraft, and does demonstrate what scaling in the aerospace industry is really all about. There are also no major "show stoppers" to the Falcon V other than government bureaucracy and idiots in congress calling it a "munition".

I see a number of things that will prevent a scaled up or modified version of SS1 from being successful as an orbital spacecraft. On the other hand, if you compare the DC-3 to the DC-10, there are some similar features between the two aircraft, but it also shows huge leaps of logic as the aeronautical engineers finally figuered out how to build aircraft. I'm willing to do a "wait and see" on this new design by Scaled Composites, but I am very skeptical.

Re:Why SpaceShip[One|Two|Three] will not reach orb

[FleaPlus]

I'm under the impression that the direct speed/altitude benefits are fairly small. Rather, the main benefits are from safer abort methods (you can parachute back down if your engines fail) and being able to build an engine optimized for the upper atmosphere and space. You also don't have to pay launch site fees, and liability insurance becomes easier to deal with. Here's a relevant quote from t/Space's site:

http://www.transformspace.com/index.cfm?fuseaction =projects.view&workid=CCD3097A-96B6-175C-97F15F270 F2B83AA

The major benefits of air launch come in safety, simplicity and flexibility. Crew safety is enhanced because abort-at-ignition is easier when the capsule already is high enough for parachute deployment, vs. the on-the-pad challenge of releasing sufficient energy in the correct direction to send the capsule high enough for the parachutes to deploy. Public safety is enhanced because the launch takes place over open ocean, well away from any populated areas.

Air launch also allows simpler engines, which don't need to be designed to operate at both sea-level air pressure and at altitude. The "all-airborne" operation also reduces the performance penalty of using inexpensive low-pressure tanks and engines.

Flexibility and responsiveness is greatly enhanced by air launch. Most winds and precipitation at the airport runway -- launch site -- don't delay a launch; the carrier aircraft simply flies to clear weather. In addition, responsive launch often requires matching a particular inclination and orbit phasing. The carrier aircraft over open ocean can launch the CXV to any azimuth, and by flying across longitudes, can quickly match a desired orbit phasing.

The t/Space version of air launch provides only modest performance gains, in the 10-25% range, compared to a ground launch. It does not attempt technically difficult challenges such as accelerating the launch aircraft to supersonic speeds, or reaching very high altitudes.

Re:Ticketprizes?

[FireFury03]

$100.000 for flying from LA to Sydney in approx 4 hours?

Plus a 4 hour checkin and a body-cavity search at customs...

On private spaceflight...

[10Ghz]

Not really related to the articl, but... I'm getting pretty annoyed by this "look at what this small company is capable of doing, while NASA wastes billions of dollars!". Hell, Rutan himself made some similar comments (was it on 60 Minutes?).

Yes, What Rutan/Scaled Composites did is great, no denying that. But comparing their budget to NASA's is ludicrous. Does Scaled Composites maintain orbiting space-stations? Does Scaled Composites build orbiting space-stations? Do they conduct scientific experiments on other planets and in space? Do they send probes to comets and Mars? Rutan and Co managed to put a spacecraft for a short amount of time in to edge of space. NASA did that in 1961.

Rutan and Co have the advantage of having the knowledge that NASA and others have accumulated over the years at great expense. They use that knowledge, and then make remarks how NASA is "wasting money". Well, without that "waste of money", SS1 would still be nothing but a glimmer in Burt Rutans eye.