TAAS Company Presents New Orbital Space Plane 80
RobGoldsmith writes "The TAAS Company have released details on their new Orbital Space Plane. The new design has many attributes to set it apart from its rivals. One highlight is the integrated Safety System; this is where an escape vehicle can eject from the main body of the craft then fly home safely. They claim: 'With the system's performance capability, economical first stage tow and independence from ground launch facilities, it can offer the lowest price. It also offers the safest flight.' Could this spaceship rival Virgin Galactic's SpaceShipTwo?"
Reader wooferhound points out related news from XCOR Aerospace (which we've discussed previously), that they're beginning to take orders for seats on their own suborbital flights, with test runs planned for 2010. Seats will be going for around $95,000 each, less than half the cost of the first tickets for SpaceShipTwo.
Orbital? (Score:2, Informative)
"The TAAS Company have released details on their new Orbital Space Plane."
Is the word "orbital" being used in some context I don't understand? This vehicle does not appear to be anywhere close to capable of reaching orbit. "Suborbital space plane," I can get behind.
Not much room, but good to see the escape module (Score:4, Informative)
Funny - looks a little like the original Learjet.
Nice to see the escape module. Bearing in mind that even NASA - and the Russians, Chinese etc. - have had some spectactular & sad blow-ups, it would seem likely that some of these less well resourced attempts will have the same. Shame there was not one in the shuttle - I seem to remember it was in the original proposal?
Neat idea also to tow the thing up, therefore avoiding the need for a special launch aircraft like Rutan's designs. Still, he did get there first, and this thing's only on paper...
Re:Orbital? (Score:3, Informative)
Re:Orbital? (Score:5, Informative)
Well, it clearly wasn't RobGoldsmith's fault. The article does indeed claim this business-jet sized craft will reach orbit. The first stage would be a tow plane.
I'm just not seeing this. The tow plane can get the vehicle to a moderate altitude, but nowhere near orbital velocity (delta-v=20,000 km/hr, after drag?). You'd need a mass ratio of 10-to-1 on propellant ("easy" with a capsule that jettisons everything behind it; much harder with a space plane), and you'd have to be using something with an extraordinary Isp, around 320. That probably means cryogenic propellant. So this plane is made of cryo-compatible low-weight, reusable materials? Are there turbopumps on board? I don't see a rocket engine, I see a nozzle. OMS? Reentry heat shield? How do you restart your engine for a controlled reentry burn? Do you keep propellant in those tanks for that? Have you accounted for O2 slosh?
This just doesn't LOOK like an orbital vehicle. To build an orbital craft with that profile and no significant 1st stage would require ludicrous developments in materials science.
And his answers come across as insanely naive.
No, it can't possibly. You don't even have a prototype, so I can't even entertain such a statement.
NASA hasn't demonstrated a space plane, so how can they have demonstrated towing one? They may have demonstrated towing a REGULAR PLANE. It is true that NASA has launched orbital missiles from airplanes (not via tow, however, to my knowledge).
Oh, well that settles that, then. Who wrote this?
That won't even pay for your propellant. For reference, a new Lear Jet STARTS at $5 million. That's off-the-lot; all development costs behind it. So an orbital space plane costs less, including R&D than a Lear Jet? How about the tow plane? Does that come free?
No, spacecraft do not "easily" scale up. You pick your target orbital payload mass/velocity and you do whatever it takes to get you there. You can't build an orbital, man-rated spacecraft, and then just multiply the entire thing by 1.3.
So, really, no design yet?
I read up a bit on Robert Talmage. His expertise seems to be in rescue/escape vehicles. I think this entire thing is a publicity stunt for his cockpit-jettisoning escape system (which is all they really talk about in that article; they don't mention fuel or engines once), which, for the record, seems to depend on lifting surfaces:
I'm sure Mr. Talmage has some hand-wavy answers to all of these questions, and I would LOVE to get my hands on a $4 million space ship. But I think it's safe to say this guy has his head in the clouds, not his hardware.
The Deam Is Way Too Alive Sometimes (Score:3, Informative)
TAAS: Who? No matches to TAAS or Talmage when searching Personal Spaceflight http://www.personalspaceflight.info/ [personalspaceflight.info] or Encyclopedia Astronautica. The latter is particularly notable, as the NASA history office recommended it to National Geographic when they were looking for some historical data. TAAS apparently recognizes itself though: taascompany.com
Stability: "With the center of gravity now well behind the center of lift, the parent vehicle will be unstable and pitch up." All true, basic aerodynamics. Specifically AEROdynamics. This will be true in the atmosphere. If the vehicle is in the atmosphere, there's no reason to rely on structural aerodynamics, because the vehicle has control surfaces. A much safer ejection sequence would be to kick the capsule forward, lower the flaps for aerobraking, trigger any other brakes that may exist, lower the elevators to "nose" down the main vehicle. Bring it down and away from the capsule under control is far safer than hoping instability won't backfire and somersault the tail over and forward, into the capsule.
Wings and Reentry: "Wings are the most efficient means of air transportation and air-breathing engines are the most efficient form of propulsion. A vehicle that takes advantage of these two components will be the most efficient. The wings also play a role in orbital transfer maneuvres and reducing thermal loads during re-entry."
The fastest atmospheric speed ever achieved was Mach 9.6 by NASA's X-43. The "wings" were integral to the airframe. Nothing that pokes out from the body like those imagined for the TAAS thing would stay attached at anywhere near that speed. And nothing running at lower Mach could possibly make it outside enough of the atmosphere to accelerate to orbital speed unless it were carrying an enormous fuel load to make up for lack of lift since the wings wouldn't be working any more.
As for reentry, the wings would absolutely be a hindrance. The greater surface area (as compared to the body alone) would result in much more aerodynamic compression heating than any amount of radiative cooling that could possibly occur. Now, if they were to use the wings as ablative cooling, by having them absorb heat and then get ripped off by the high Mach forces, it might just bear itself out to be as silly as the rest of the article.
A couple details to put some of this in context: Low Earth orbit speed is around Mach 25.
The temperature of the X-43's leading edges approached 4,000 degrees. The SR-71's reached 3,300 at Mach 3.3. The nonlinearity in the speed/heat comparison was due the the X-43 flying much higher (110,000 ft); less air, less heat generated.
Re:Not much room, but good to see the escape modul (Score:4, Informative)
At least one successful ejection has been made from an SR-71 at mach 3, which is roughly the speed that Challenger was doing when it broke up, assuming that your 1km/s figure is correct. The reason why this was survivable is because what kills an ejecting pilot isn't speed, but rather dynamic pressure caused by speed. Dynamic pressure increases with the square of speed ,but it also drops off with altitude. Your 300m/s figure is correct, but that's assuming a sea-level ejection. If you're at a high altitude then the true speed goes up accordingly. (If you're familiar with aviation terms, it's the indicated airspeed that kills you, not the true airspeed.) I don't know how high Challenger was when it broke up, but if it was more than about 12 miles then it's conceivable that ejections from it could have been survivable.
Not to take away from your post overall, as you make many excellent points, I just wanted to elaborate on that one thing.
Re:Not much room, but good to see the escape modul (Score:2, Informative)
F-111 had an ejection capsule which protected occupants at high speeds, up to the top Mach 2.5 speed
http://www.f-111.net/ejection.htm [f-111.net]
Re:This proposal is irritating (Score:2, Informative)
Manned space flight will have to be demanding and precise no matter who does it. You're right that the "difficult" part may have more to do with NASA than anything.
Otherwise, I totally agree. The shuttle was deeply flawed, and NASA is a deeply dysfunctional organization. But for all its flaws, the shuttle is real and not imaginary.
Of course, the shuttle has cost real dollars and real lives, whereas this fellow's fantasy ship hasn't hurt anyone and probably never will (because nobody would fund it). So I guess to be morally consistent, I would be better off directing my ire at NASA.
But there's a certain arrogance and laziness in the posted article. It's like it can't even be bothered to pretend to be a real spaceship.
One can argue that, for all its flaws, the shuttle was an earnest attempt at creating a revolutionary space architecture. One doomed by bureaucracy, politics, mission creep, economics and technological deficiencies, perhaps, but REAL.
I'm all for privatization of space, and part of privatization is criticizing the hell out of weak proposals. Part of it is getting a little angry at inferior products and ideas. Part of it is being impatient with insincere companies.