Transterrestrial Musings

Comments

Actually, I _remain_ skeptical about the prospects for commercial human spaceflight. I am simply less skeptical than I was before. I still think that it could be a decade or two before regular suborbital tourist flights are possible. And I think it could be several decades or more (if ever) before orbital tourism becomes practical.

A few things have changed my skepticism a bit. First, I think that there are some more serious contenders on the stage now than there were only a few years ago. Rutan is obviously serious and capable, whereas I thought that outfits like MirCorp and a few of the other groups in the 1990s were not based in reality. Second, I have been impressed by some of the analysis of this subject that has been done by some serious people. For instance, I know some of the people at Futron who have studied the commercial space tourism market. Although I have not read their report, I respect their abilities. If they say there is a limited market, then I believe them. And I have also been convinced by some other arguments, such as the claim that an active suborbital market can foster a possible orbital market. See, for instance:

http://www.thespacereview.com/article/73/1

(this is a well-researched article)

I still have strongly negative reactions to the naive overenthusiasm about space tourism, and I also find the "NASA=Evil" argument to be silly. And although I don't think that NASA has its act together, I still think that it is the only realistic organization for conducting human spaceflight and space exploration. But there have definitely been some positive developments in the private spaceflight field and I hope (and expect) to see more.

Posted by Dwayne A. Day at June 23, 2004 06:18 AM

One other thing: a more descriptive title would be "Suborbital Survivor," because I think that what we will see is a sub-orbital spaceflight prize for a reality TV show. There remains a big gap between sub-orbital flight and orbital flight--in speed, technology, and cost.

My guess is that they will pick some catchy title like "Race to Space" or "Space Challenge" or something macho.

Posted by at June 23, 2004 06:39 AM

It's not too hard to see how to carry the Survivor model directly over to Race to Space (which would be my name for the show) - simply replace reward and immunity challenges with tasks carried out in neutral bouyancy tanks and vomit comet flights. Give the survivors access to hydroponic gardens to try growing their own food in "moon base" conditions and so on.

I'd particularly like to see a reward challenge on a vomit comet that involved trying to jury-rig CO2 filters as in Apollo 13.

Posted by Andrew Case at June 23, 2004 07:00 AM

I think one of the most important results of the SS1 flight is that it has eliminated the "giggle factor" associated with the concept of space tourism. It wasn't so long ago that talk of space tourism was greeted with skepticism and even derision from the establishment. Now, serious people like Dan Rather on the CBS evening news are talking about it with a straight face.

It remains to be seen if space tourism will be profitable or not. Certainly there is a notional demand for it, as per the several market studies that have been performed. The question is whether or not the demand will hold up once the risks and realities of space flight are more widely appreciated.

But the attempt will be made. And making the attempt will open the door to other possibilities for the further commercial development of space. Some of these possibilities may not even have been concieved of yet. I think these unknown unknowns are where the true potential of space development are to be found.

Posted by Frank Johnson at June 23, 2004 07:16 AM

Spaceship survived control problem
Glitch may hurt X-Prize chances

http://www.floridatoday.com/news/space/stories/2004b/spacestoryN0623SPACEONE.htm

The comments I found most enjoyable was to set his sights on loftier goals and might stage orbital test flights sooner than you think. We know it's crucial to dramatically reducing the costs (of space travel).

Posted by Harold LaValley at June 23, 2004 07:39 AM

One quibble:
"The problem is that each engine costs on the order of $100,000 and cannot be reused."

Uh, does 'reused' mean something other than refilling the 'solid' portion, recharging the oxidizer tank and inspecting/refrubishing the nozzle?

Randy

Posted by Randy Campbell at June 23, 2004 08:10 AM

One 'quibble':
"The problem is that each engine costs on the order of $100,000 and cannot be reused."

Does 'reused' suddently mean something OTHER than refilling the solid portion, recharging the oxydizer tank, and inspecting/refrubishing the nozzle assembly?

Randy

Posted by Randy Campbell at June 23, 2004 08:15 AM

Randy,

I don't know. Theoretically, Dwayne did his research, and that's a number quoted from Burt. I have noticed that the aft sections of the engine/nozzle look significantly different between some of the different test flight photos. And I don't mean that "there was a fairing in one, and not in the other", but that the ship itself looked like it was a significant length longer/shorter and had different sized nozzles, etc, between photos from different flights.

However, if that's really the case, and a new engine is needed for each flight, then doesn't/shouldn't that disqualify SS1 from the X-Prize based on the "do it again within 2 weeks with the same equipment" requirement?

Not having read the full rules myself, I can't say for sure, but I would think/hope that it would. Not to take anything away from Burt and Scaled, but that level of reusability should have been part and parcel to the design, not a "necessary evil".

Posted by John at June 23, 2004 08:24 AM

John, I don't know the rules either, but I would imagine they make some sort of exception for solid fuel rockets which are consumables by design. Using your argument, a hand gun is not reusable unless you reload your own shells. As you can see from their design it is relatively easy to slide one motor out, and put a second one in.

Posted by Jeff at June 23, 2004 08:54 AM

Quoted directly from the X-Prize rules:

Toward this end, no more than 10% of the flight vehicle's first-flight non-propellant mass may be replaced between the two flights.

and

The flight vehicle must return from both flights substantially intact, as defined by and in the sole judgment of the ANSARI X PRIZE Review Board, such that the vehicle is reusable.

Posted by Andrew Salamon at June 23, 2004 09:18 AM

Xprize guidelines http://www.xprize.org/teams/guidelines.html

See #4 - no more than 10% of the non-propellant vehicle weight may change between flights.

Posted by Sean at June 23, 2004 09:34 AM

Mr. Johnson wrote:
"The question is whether or not the demand will hold up once the risks and realities of space flight are more widely appreciated."

I think that's the key question. It now appears that SS1 came much closer to failure than one would like. If it had failed and killed the pilot, that would have been a significant setback to the entire effort (investors in other projects would get cold feet).

However, there are other questions as well. Assume a successful sub-orbital tourism market. What real difference will that actually make if the tickets are still too expensive to be within reach of the vast majority of people who want to go? Space tourism advocates always cite the extreme (risky) tourism market as proof that there is a market for space tourism. Assuming that is true, then does that do us any good? Is there a substantial difference between space access for a few elite government astronauts and space access for a few rich extreme thrill-seekers?

Now referring to the article I linked to above by Clark Lindsey, there is reason to believe that there are positive aspects to a vigorous suborbital space tourism business, even if it remains beyond the reach of most mortals with a mortgage. But one has to keep from getting too overheated on this subject.

Posted by Dwayne A. Day at June 23, 2004 09:37 AM

Mr. Campbell wrote:
"Uh, does 'reused' mean something other than refilling the 'solid' portion, recharging the oxidizer tank and inspecting/refrubishing the nozzle?"

A valid quibble. However, I pointed it out to draw attention to the fact that this cost has to be paid _every single flight._ In other words, it is not a $100K engine that you buy only once and simply pour more fuel into. This is not a one-time expense for a reusable engine.

Posted by Dwayne A. Day at June 23, 2004 09:39 AM

Jeff,

I guess that the rub for me is that solid rockets, as consumables by your own admission, aren't reusable. I would like to thank the others for pointing out the "10% of non-propellant mass" part of the X-Prize rules, as that is the part I was looking for and/or confused about. I'd rather see less use of solid rockets, but as long as a substantial portion of the vehicle (in this case, 90% or more) is being re-used, I'll agree with Ansari that it's considered reusable.

Your comparison of a reusable sub-orbital vehicle and a handgun is a little suspect, however. The handgun is a delivery mechanism, with the "payload" being the actual bullet in the shell. When we're talking about the X-Prize, the delivery vehicle and its payload are supposed to be one in the same, as noted by the "substantially intact" and "10% of non-propellant weight" limitations.

A handgun, long-gun, cannon, etc, is as reusable as the reliability of its barrel and moving parts (if any). But since we're not launching people into space with rail guns or cannons, the comparison doesn't really hold.

Actually, the only valid comparison in terms of reusability and guns would be to compare it to a cartridge, with the SS1 and engine as the casing and the propellant as the gunpowder (the bullet itself isn't considered). The goal of the X-prize is to build brass casings, not aluminum, as aluminum casings generally can't be re-laoded, while brass casings can. In this case, the casing's base (the SS1) is brass, and reusable, but the shell of the casing is aluminum and needs to be replaced along with the gunpowder after each firing.

Either way, the handgun itself could only possibly be the runway or White Knight, and is completely reusable, as it is just a delivery mechanism, and not the actual vehicle.

Posted by John at June 23, 2004 11:32 AM

Quoted from Andrew:

"I'd particularly like to see a reward challenge on a vomit comet that involved trying to jury-rig CO2 filters as in Apollo 13."

Good idea but I think you'd have to get more base than that. Perhaps a ride on a vomit comet where once they hit microgravity the contestants would have to down a strawberry, snail, and goat brain smoothie. Then you'd have a real vomit comet challenge.

Posted by Hefty at June 23, 2004 12:03 PM

You must understand that the 10% applies to the total launch system, including the first stage launch platform. Base your calculations on that reality.

Posted by Miguel at June 23, 2004 01:16 PM

I'm not going to comment on all of this discussion, except to say that I'll be very interested to see if SpaceShipTwo uses a hybrid motor. The great thing about this is that the market is starting to work, and we'll see which proves out to be the best solution.

Posted by Rand Simberg at June 23, 2004 01:22 PM

Keep in mind that SpaceShipOne was designed to win the x-prize on a tight schedule. A hybrid rocket has problems for a reusable spacecraft. It also has low specific impulse compared to many liquid-fuel rocket designs. That’s why high reliability liquid-fuel rockets are part of most reusable designs.

Dwayne, you said:

“…I also find the "NASA=Evil" argument to be silly. And although I don't think that NASA has its act together, I still think that it is the only realistic organization for conducting human spaceflight and space exploration.”

The issue is not that NASA is “evil,” but that it is a government bureaucracy pushed this way and that by political whims, boxed in by rules. It is, and has, operated just as one would expect such to operate. It is unrealistic to think it can be radically changed. Currently, NASA can't even put people in space. A private company can.

Posted by VR at June 23, 2004 02:18 PM

I suspect 'SS2' (if built) will have an all-liquid motor. The cost and operational disadvantages of the hybrid approach will have been well-established by then.

Maybe XCOR can sell them a few?

Posted by Paul Dietz at June 23, 2004 02:22 PM

Hi Dwayne,
Thanks for posting the link to my article. I tried to give the issue a fair review even though I'm obviously biased towards the idea that suborbital will help lead eventually to lower cost orbital access.

I definitely agree with your article that suborbital spaceflight will make a space-themed reality TV show practical. I expect that concepts like winning rides via a lottery or in a promotion contest will also become viable.

I see the ISS flights as more a proof of the existence of an enthusiastic market for space tourism than a real business. That is, if a handful of people are willing to spend $20M, there must be a whole lot of people willing to buy lower priced tickets. As you indicate, at this price point, orbital is just too hard. That's a significant amount of money even for a company like Pepsi that might want to sponsor someone like Bass. If the ticket had been $2M the deal would have closed easily.

- Clark

Posted by Clark at June 23, 2004 02:37 PM

Actually, I _remain_ skeptical about the prospects for commercial human spaceflight. I am simply less skeptical than I was before.

That differs in no way from what I wrote. I said that you were slowly coming to your senses, not that you'd completed the process. I was describing the journey, not the destination. ;-)

Paul, I'll be discrete and say nothing more on this matter other than what I said...

Posted by Rand Simberg at June 23, 2004 03:17 PM

Mr. Linsey wrote:
"That is, if a handful of people are willing to spend $20M, there must be a whole lot of people willing to buy lower priced tickets."

I think I pointed this out in the article, but the actual cost that both Tito and Shuttleworth paid was considerably less than this--around $12-15 million.

I got that from two separate, independent, reliable sources. One of them was actually involved in contract negotiations with the Russians. Another was at NASA when Tito came in after his flight to brief them. Tito admitted to the NASA people present that he paid about the same amount as the European astronauts have paid for their seats. The $20 million is simply the public price.

Posted by Dwayne A. Day at June 23, 2004 03:36 PM

All this discussion and no jokes about contestants being voted off the planet?

Posted by McGehee at June 23, 2004 07:43 PM

Sorry, Dwayne, I was in a hurry to go to dinner (see Andrew's posting.) I should have said "on the order of $20M". I've also heard many times of lower figures than the $20M usually cited. However, the range $12-15M is still a lot of money and my point still holds.

BTW: Since you are an authority on spysats and are now considering the prospects for suborbital vehicles, I would be very interested in what you think of using a suborbital for reconnaissance and remote sensing. These are markets that TGV is targeting rather than space tourism. Advantages include the fact that a suborbital vehicle can see a much larger area than a camera on a plane and it can fly at unexpected times, unlike satellites that cross an area on predictable orbits.

For example, after a couple of Japanese spysats were lost on a failed launched last year, it occurred to me that a suborbital popping up from southern Japan to 100-150km could see all of North Korea. The cost would need to drop quite a bit to do this regularly but during a crisis period it might be very useful.

Posted by Clark at June 23, 2004 09:37 PM

"All this discussion and no jokes about contestants being voted off the planet?"

Nah, the losers are voted _back_ to that wretched planet.

Remember this ?
"It seemed to me," said Wonko the Sane, "that any civilization that had so far lost its head as to need to include a detailed instructions for use in a package of toothpicks, was no longer a civilzation in which I could live and stay sane."

Posted by at June 24, 2004 06:14 AM

Mr. Lindsey wrote:
"I would be very interested in what you think of using a suborbital for reconnaissance and remote sensing. These are markets that TGV is targeting rather than space tourism. Advantages include the fact that a suborbital vehicle can see a much larger area than a camera on a plane and it can fly at unexpected times, unlike satellites that cross an area on predictable orbits."

It is an interesting idea, but I suspect that there are some serious problems with it. I'll list a few issues off the top of my head:

-Airspace sovereignty--are you going to fly such a vehicle entirely in international or controlled airspace? If not, then flying what is essentially a ballistic missile over another country can quite possibly be considered an act of war. Now if the adversary lacks an ability to react in any meaningful way, then this is not that important. But many countries might see this thing coming and wonder if it carries a nuke.

Closely related to this is how other neighbors might perceive it. What does China think when it sees that ballistic vehicle arcing out of Japan to spy on North Korea? Does it think that it might be headed for China?

Equally related are all the operational issues, such as where you do the recovery. Does it have to land at the launching site? If so, this seems to limit its utility.

-Obliquity--generally you want to cut the distance from you and your target as much as possible. The best way to do this is to fly over it and look straight down. Two hundred miles over North Korea is two hundred miles straight down. But if you launch from Japan in a big arc and then try to measure the distance to North Korea you're staring down the long angle of that triangle. That's going to be a long distance. And you're going to be staring through the dirty part of the atmosphere.

-Focal length--how big a camera can you cram into such a vehicle? You need long focal lengths and big apertures. Because of design considerations you are unlikely to get much of either. And you also are going to have to stare out a transparent window, which is not good for long focal length cameras. Keep in mind that current US spysats have massive focal lengths. You cannot approach anything like that with a suborbital vehicle, and you're going to be much farther away.

This kind of stuff has been explored before by the US. During the 1960s the CIA undertook two projects called ISINGLASS and RHINEBERRY. I have little information on the latter, but the former invoved a Dyna-Soar like vehicle intended to be launched from under the wing of a B-52 to arc high over an adversary. It was technically challenging, but one big problem that killed it was that the CIA determined that the Soviet Union would see such a launch as hostile and might start WWIII because of it.

I just don't see this kind of vehicle as having much utility for reconnaissance. The key in recon now is long dwell times. Get over the target and stay there as long as possible. The best ways to do this appear to be high altitude stealth UAVs.

Posted by Dwayne A. Day at June 24, 2004 06:48 AM

Er, I didn't say which planet...

Posted by McGehee at June 24, 2004 06:54 AM

Yes, there is. The key is economies of scale. NASA has been unable to employ a considerable portion of its astronauts in space. There's a natural upper limit on how many elite government astronauts can go into space. I think the shuttle achieved that limit.

OTOH, there's a lot of less wealthy thrill-seekers out there, not just the few extremely rich ones. So a few thrill-seekers in space doesn't do much for space science or technology, but they do enable space tourism, a new business to exist. As companies reduce the cost of putting people into space, they can expand their operations and take advantage of economies of scale. Space tourism can be expanded significantly. All it takes is consistent lowering of the cost.

So a few elite astronauts in space now doesn't imply any expansion of activity in space, but real paying tourists in space means that there's great incentive to make that service cheaper in order to attract larger numbers.

Posted by Karl Hallowell at June 24, 2004 10:36 AM

Dwayne, thanks for the interesting response. Taking the TGV Rockets vehicle as the model, it just goes straight up and down using a powered landing. So infringement of another country's territory is not an issue for them.

Obliquity is clearly a problem. However, their vehicle will carry upwards of a 1 ton payload, modest by big spysat standards but still not bad. I think you could fit a fairly good sized camera on it.

Ideally long dwell times are best but, as you say, that can lead to wars if you put a vehicle right over the top of the target. I'm thinking more along the lines of a quick popup above southern Japan to check if North Korea is, say, working around a missile site during periods when they know there is no spysat going over. Just seeing that there is unusual activity of some sort going on might be very interesting even if you don't have great resolution.

Spysats can scan large areas but the target country knows when the sats are in view. An air vehicle sees a much smaller area and must avoid being detected. Seems to me there is a niche between these systems where a suborbital popup style observational platform could be useful.

Posted by Clark at June 24, 2004 11:15 AM

Clark wrote:
"Seems to me there is a niche between these systems where a suborbital popup style observational platform could be useful."

I'm not convinced. It strikes me as a pretty narrow niche. And my understanding of Cold War era systems is that the obliquity issue is a big one. It really stinks to have to stare through hundreds of miles of atmosphere at an angle.

Posted by Dwayne A. Day at June 24, 2004 07:11 PM

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