Another You Might Be a Space Nerd Moment

You might be a space nerd if out of curiousity you get out a tape measure to try and calculate your appartment's volume in cubic meters, so you can get a feel for how big it is relative to a Bigelow module...

PS the answer was ~140.

Latest MSS Update

As the X-Prize Cup draws near, we've been very busy here at Masten Space Systems. Ian, wrote our latest update earlier today. As Ian points out, we've been learning a bunch about our system that is actually accelerating the overall XA-1 development path, even though the delays and "learning experiences" have somewhat delayed the first flight of XA-0.1. The nice thing is that little by little we're getting a really solid piece of hardware, and more importantly an understanding of what we need to do next time. The learning curve in this business is very steep and unforgiving, but it's really exciting at the same time realizing that we're almost there.

I remember last year when we were slogging through all the issues debugging our test trailer and trying to get our first succesful hot-fire test. I remember that giddy feeling though, when we were finally getting there, and that's what it feels like all over again. Seeing this vehicle stand in the air on quadruple plumes of flame should be a sight to behold.

Unfortunately, as Ian points out, we won't be competing this year in either of the Lunar Lander Challenges. Trying to field three new vehicles, assemble test and debug 40 igniters and 20 engines, including pumps, flight weight tanks, new landing gear, and everything was just way too much for a four-man rocket team (especially with one of those spending most of the summer working with the AST on experimental permits). As it is, our main focus has always been trying to get a rock-solid reliable vehicle that can take payloads (and eventually people) to space and back.

We wish John Carmack and his team (as well as the Microspace and Acuity teams) a lot of luck this year. We'll still be there, and we'll probably do some sort of live-fire demo (possibly an endurance run on one of our vernier engines), we just won't be competing this year.

Even More Random Thoughts About Sundancer

A commenter earlier brought up an interesting thought that's been bugging me for a while. Bigelow is trying to build his 3-person Sundancer module to be light enough to launch on either a bare-bones Atlas V, or a single-stick Falcon IX (or a Soyuz for that matter). However, he's not going to actually ramp up the available capacity to 9 people until 2012 when Nautilus is on-line. Now, this might actually make sense, if nobody is able to field a manned commercial vehicle with high enough flight rate to keep Sundancer busy until then. However, if someone is able to come up with a passenger transportation solution, it might be better for Bigelow to just crank out a few more Sundancer modules while he works on finishing up development on Nautilus. That way he can ramp up demand more smoothly, and benefit from higher flight rates (and hence lower ticket prices and more demand for his modules) sooner rather than later.

Sundancer is also conveniently small enough that it'd probably make sense to have more than one station in more than one orbit/inclination. A Sundancer module for instance might make a good core for a transportation node/fuel depot. By having the fuel depot man-tended, all of the Autonomous Rendezvous and Docking issues, as well as the automatic propellant feed coupling issues go away, as you can use man-in-the-loop controls to simplify the former, and could just manually connect couplings for the latter. Or you could see having one or two Sundancer modules used as free-flyers for microgravity research/production. Once every couple of weeks, a new supply ship would get there, tend the station, load and unload new experiments or raw materials/processed materials, perform any preventative maintenance needed, get the experiments started again (and do any debugging needed) and then close it back off and head home. Or if you had such a free-flyer in a close formation with a manned Sundancer station, you could ferry back and forth to the unmanned free-flyer if problems cropped up, without having to have people on-board continuously, which tends to greatly degrade the microgravity environment (us humans are clumsy louts).

Other uses could be like I mentioned previously, as "mission modules" for use with commercial capsules to allow for long-duration spaceflight. Combine this with a refueled upper stage of some sort (either a K-1 like I've discussed, or a Falcon IX upper stage like I talked about way back, or a refueled Centaur like LM has discussed), and you could very well have commercial translunar missions before the Block I CEV is even in service.

One other point I ought to discuss. As I mentioned in the other post (and previously in my writeup of my Bigelow visit):

While in there, I was able to pick the brain a bit of the engineer who was giving us the tour. I had been curious to find out if Bigelow was interested in doing subscale versions of the module for potential use in lunar transfer vehicles or other applications. The answer I was given was that Bigelow would probably be willing to work out some sort of a deal if there was sufficient interest. I also asked him what the current plans were for launching the station, since the reported weight of 50,000lbs puts it at the upper end of what current ELVs can deliver to orbit. He mentioned that they were looking at several options, including launching all at once on a Delta IV Heavy, or maybe a Proton, or even The Stick if it gets developed. He also mentioned that if those didn't pan out, or if a lighter lift but more affordable booster was on the market, that they might launch it in several pieces and fit it out on orbit. As it is, there's a decent amount of on-orbit fitting out anyhow for an inflatable module, so this isn't as big of a hassle. A lot of the quoted weight is probably in the water bags used for radiation control, and in other internal pieces, so maybe flying it on three or four Falcon Vs might be possible. He didn't state what the minimum mass they could break it down into was though.

One thing that means is that if Nautlius could be launched partially loaded, and then the rest of the gear brought up and installed on a second flight (possibly halving the required minimum launch weight), the same may hold true of Sundancer as well. Which means that it could possibly be launched mostly empty on a K-1 (if they become available), and then fitted out on a subsequent flight. Sundancer is also small enough that if you really can launch the thing empty, and then fit it out with subsequent flights, that makes using it as a lunar surface module a lot easier. Having a commercial lunar lander that can place 10klb on the surface or even 20klb is going to be far easier than a 45klb cargo lander.

As an old Role-Playing Game manual once said "the potential uses are limited only by the heights of your creativity, or the depths of your neurological disorders."

Anyway, I think that although Sundancer is seen by Bigelow as a short of near-term solution to get some sort of destination up there, to start the ball rolling, I think that this design may very well have far more potential than that.

More Thoughts on the Lockheed/Bigelow "Deal"

Now that I've had a chance to put forward some back-of-the envelope analysis showing why I think Lockheed could possibly meet the $10M/ticket price range that Bigelow is trying to achieve, I want to put a few more thoughts down.

One of the common refrains I've heard from many commenters are of the "Big Evil Lockheed is trying to scare away SpaceX and RpK, and steal their markets". I'm not sure how realistic that fear really is. The most important consideration is that fact that in order to really be price competitive, Lockheed has to get almost all of the Bigelow contract. I'd be surprised if they could eke out any profit at all at a $10M/ticket price if they didn't get at least 12 out of the 16 flights per year that Bigelow is planning on post-2012. However, Bigelow isn't dumb enough to tie himself to a single flight contractor, so it's an open question if Lockheed really could lock up enough flights to make the $10M/ticket rate feasible.

If you look at Lockheed's revenue for their Atlas V program vs my estimate of a $40M internal marginal cost per booster, you see that their fixed costs are likely in the $200-500M/year range. SpaceX on the other hand has barely passed the $100M mark after about four years of operation, including major engine and vehicle development. There's a chance that in the rush to build the Falcon IX and Dragon, that they might get a big more bloated, but it's unlikely that they'll up their total burn rate by that large of a margin. The upshot is that SpaceX probably only needs 3-5 flights per year in order to make a profit at their current targetted Falcon IX prices (which is less than half of the optimistic price for a high flight rate Atlas V). So, if SpaceX actually manages to get their technical act together and start flying reliable vehicles (which alas is still an if not a certainty), they can likely offer a better price without having to take anywhere near as large a share of the market.

That I think bodes well for SpaceX. Having to hold most of the market to keep yourself profitable means that LM's hold on the Bigelow contract pretty much depends on them not having competition--which is unrealistic. If you can really demonstrate a $1B+ per year market for space transportation, do you really think that is going to scare investors away from the market? Especially when it's fairly obvious that at $10M per person, LM is probably almost as low as it can go pricewise?

Right now, the biggest threat to SpaceX's existance is itself (the same applies to RpK). They've got a talented team, but they have to execute, and execute reliably. Fortunately, between the potential Bigelow market and the COTS market, there may be enough incentive for Musk to focus on getting his core business in order, and profitable instead of stary-eyed focusing on trying to build ever bigger (and likely far less profitable) launch vehicles. Some real competition is going to force them to actually put a lot of time and effort into their Falcon IX/Dragon line, trying to get the price down, the reliability up, flight rate up, and internal costs down. As Henry Spencer put it, now that Lockheed is trying to enter the market, doing a slightly better Atlas isn't good enough--mammals have to act truly mammalian. I think SpaceX can do it.

Another key point worth bring up again about this supposed Lockheed/Bigelow "deal" is that it is not an actual launch contract. Bigelow and Lockheed have both agreed to look into things, but Bigelow has no obligation whatsoever to buy even a single Atlas V flight at this point. If SpaceX and RpK both biff it, or if Lockheed actually manages to get some real "fur" so to speak, they might wrap up the contract (or most of it) at some point in the future, but at the moment, the competition is still wide open. In fact, it's also worth mentioning that Bigelow and SpaceX already have a similar arrangement in place. If SpaceX doesn't screwup themselves, Lockheed is only going to be able to force them out if they can prove that have such a better system than SpaceX that Bigelow is willing to go with a sole-source supplier. That just doesn't seem very likely. Bigelow isn't NASA or the US government. He's not stupid.

Going back to the Lockheed "scaring away investors" idea, I have a few more things to mention. First off, investors like to see competent competitors. If there are now competitors in the field, it scares investors because they think "Lockheed and Boeing are both talented firms--if they aren't interested in this market, is there really a market?" By jumping into the fray, Lockheed has if anything greatly increased the credibility of this market just by showing that they think it deserves serious study and internal investment. Additionally, both SpaceX and RpK just got awarded pretty darned hefty contracts to develop a capability that would meet Bigelow's needs as well as NASA's. SpaceX has received enough pre-orders this year to be cashflow positive. There still are some substantial technical risks, but by the time they have to start bringing in serious outside investment, many of those risks should be substantially mitigated. If I were a saavy investor (which judging by the amount of times I've had to eat Carl Buddig meats on the cheap store-brand bread over the past few weeks, I can safely say is not the case), looking at SpaceX's position vs Lockheed's I'd consider SpaceX to be a fairly reasonable bet (though I'd still diversify). RpK on the other hand is in a slightly different category. A lot of their vehicle is done, and they also got a lot of government money now, however they don't really have a huge amount of their own capital to back that up, which puts them in a little stickier of a position. But once again, their cost structure is likely more amenable to hitting the $10M/ticket price at a much lower flight rate than Lockheed could.

So where does this leave us? Basically, while Lockheed has a chance at taking this prize, they have a lot of hard work on their hand, and the greatest threat to SpaceX or RpK is still nobody but themselves.

Atlas V for Space Tourism?

Ok, last week, when I first got sent the link to the Atlas-V man-rating paper, I noticed that they mentioned using Atlas V for space tourism. I started writing this blog post Thursday morning before the big Lockheed/Bigelow announcement, but hadn't had a chance to finish my analysis. I mentioned that I would try to finish this though, so here's what I've got:

When I first noticed the idea of using Atlas V for space tourism, I was fairly skeptical about its practicality, but I figured it'd be worth taking a look at the numbers and seeing if there is an even remotely plausible way they could make it work.

So, for this excercise in numbercrunching, we're going to use the rehash of the Futron study that t/Space did way back in their CE&R report that I talked about on the blog last year (relevant numbers start on page 44 of the post). The Futron study isn't perfect, can't tell us how many people will actually buy, and has all the caveats and exceptions you would expect from any marketing study. You can't prove a business will succeed just based on analyzing market studies, but you can at least get a feeling for if the idea is even feasible.

Ok, so first let's look at pricing. How cheap could Lockheed really afford to sell tickets on an Atlas V? The first key piece of the conversation is the point made in one of the Lockheed papers (which for some reason is no longer linked-to from the main Atlas-Yesterday, Today and Tomorrow page): very low flight rates drive costs up substantially. While it's fairly well understood that higher flight rates are better, I think that Figure 6 from that paper illustrates the point rather well:

A lot of people have commented on how Atlas V's "cost" $138 million each right now, and that thus they would be way too expensive for commercial tourism. But this ignores the effect of flight rate on costs and prices. Basically, there's certain fixed costs that have to be paid every year regardless of if you launch once, twice, or twenty times. You need to keep engineers on staff, pay for upkeep of your pad and factory, pay leases on your manufacturing equipment, etc. At very low flight rates, all of that has to be divided up between only a few launches. As more and more launches occur, the cost per launch ends up trending downward to the marginal cost per flight, which for EELVs includes the marginal manufacturing cost of one extra vehicle. One thing to note is that even the marginal cost goes down as you make more of something due to "learning-curve" effects among others.

So, while the average Atlas V 401 mission runs about $138M right now, if they got back up to the flight rate originaly envisioned (about 6-8 a year IIRC), the prices would likely be able to drop back to the ~$72M per launch that they were originally offering. It's interesting to realize that if they were offering the Atlas V 401 at $72M, it probably means that their internal marginal cost per booster is much less than that number. Possibly as low as $30-40M. So, at current flight rates, they're charging about $138M each (for 2-4 per year), which would likely drop to $70-100M if they got back up to 6-8 flights per year, and possibly as low as $50-70M each if they got up to 15-20 flights per year. If they had sustained demand for 15-20 flights per year, they could probably reinvest some money into more streamlined manufacturing and operations (ie adding more automation, building extra pads, etc), and might be able to push those numbers down a little bit farther. However it's really not clear how much lower than $50-70M they could push their prices without impacting their bottom line.

For comparison, their 2-4 launches per year is probably netting them somewhere between $300-700M per year (average mission price of say about $175M). Aren't they also getting a $500M per year subsidy from DoD every year just to stay in the launch business? So that means they're making $800-1200M per year off of their Atlas V line. At $70M in revenue per flight, that's $1.4B per year (unless they can somehow trick the DoD into continuing to pay them a subsidy for their existance--don't laugh if anyone can pull that off, it's Lockheed), which is only a little better than they're making launching 4 flights per year. Now, if that subsidy went away (say as part of the ULA merger or something), then the $1400M in revenue would be a big improvement over the $300-700M they're making before subsidy.

So anyhow, I think there's a decent case that if LM really could get most or all of the Bigelow Sundancer/Nautilus business, that they could get the Atlas V price down in the $50-70M range, and possibly another $20M for the capsule leading to a roughly $10M ticket price assuming the 8-person capsule LM mentions, with 1 crew and 7 paying passengers.

So how much private demand is there likely to be at that price? Unfortunately the numbers don't look very good. As t/Space points out, wealthy individuals are unlikely to spend more than 1.5-5% of their net worth on a vacation. What that means is that for a $10M ticket to be less than 5% of your net worth, you need a net worth of greater than $200M, which puts you on par with Tito and Shuttleworth. According to the numbers at the time of the Futron study, there are about 6000 households in the world with that much net worth or greater. Once you factor in the percent that are likely to be interested, that are in good health, and all other factors, you're down to a probable market of around 1000 people. In order to drive demand up enough to drive your price down to the $10M range, you need 15-20 flights per year. If say 10 of those per year were passenger flights, that would require 7% of the total potential customer base per year to want to fly. While that is possible, I'm not sure how realistic it is.

In order to really get demand high enough that that kind of flight rate isn't unrealistic, they'd need to drop their ticket price by another factor of 2 down to $5M. At that rate, you could realistically see dozens of people flying per year in the relatively near future. However, at $5M per seat, that would imply that Lockheed could sell an Atlas V flight and the accompanying passenger vehicle, at a total cost of less than $35M. Somehow I don't see that happening.

So yeah, Atlas V could possibly be a decent vehicle for space tourism, but probably only if it had no competition, and a lot of luck in marketting rampup. Not to mention dealing with their corporate culture issues--transitioning from a business that makes most of its money off of government contracting to one that is mostly commercial oriented is not always an easy or smooth process.

Anyhow, what do you all think?

Sundancer

As most of you have now read (either here or here), Robert Bigelow announced at the Space 2006 conference today in San Jose that they are going to try and launch their first manned space station by late-2009/early-2010. This first module, Sundancer, will be about half the internal volume of the Nautilus (somewhere between 165-180 cubic meters depending on which source you read), and will be light enough (aboug 19klb) to launch on the single stick versions of Atlas V, Delta IV, Zenit Sea Launch, or Falcon IX (or Soyuz, Proton, or Ariane V for that matter). He plans a few years later to add on a full scale Nautilus module, and a service module of some sort. That'll add capacity for six more people (bringing it to nine total), and will bring the total internal volume to greater than 500 cubic meters. I've been inside of one of their mockups there in Las Vegas, and those are impressively big structures!

I read about this pretty much right after Rand posted the information, but I was busy all day at work making wiring revisions on the sparker circuitry for our four vernier engines (as well as sneaking out to the test site for a rocket engine firing), and now is the first time I've had a chance to think.

So here's a few thoughts I've had after reading the initial articles, as well as a few details I noticed:

• The LM/Bigelow "deal" mentioned this morning is really just a feasibility study. Bigelow still has a similar deal with SpaceX, and may also have a similar deal with RpK. Bigelow isn't actually committed to giving LM any or all of the launch contracts for his hotel. That decision won't be made until closer to initial launch (Rand said something about cutting contracts in 2008 for actual flights).


• Bigelow hinted that the likely price per ticket for the Atlas V based passenger vehicle would be about $10M each. That jibes pretty well with what I figured they could do at that flight rate (I have more thoughts on that coming in a future blog post). The Lockheed papers and Bigelow's comments also hint that the proposed LM vehicle would be an 8 seater. Some have compared this to Apollo and Gemini scratching their heads, but the reality is that there actually have been a few technological improvements over the past 40 years. People in most industries understand this.


• Bigelow's plan of trying to convince non-space-visiting countries to start their own low-cost space programs by sending astronauts to his station is not a crazy idea. If it works, it'll probably be seen as a stroke of genius. $10M is a bit of money for a three-week vacation to orbit, but is a pittance compared with operating a normal government manned space program. Think about it, you could spend less than 5% of what NASA spends on ISS/Shuttle per year, and still fly just as many of your people into space for just as long. And with more frequent access, you could actually do something useful there. I think that Bigelow's goal of taking the number of space-visiting nations from the current 11 to 60 over the next few years is a really good goal.


• By targetting foreign governments, businesses, and research, as well as some genuine tourism, Bigelow is helping prime the pump for private spaceflight. The big problem is that at $10M a shot, space tourism alone is unlikely to yield more than...10-15 people per year (I'll go into more detail in that other post). That's a ton compared to what we have right now, but only accounts for a few flights per year. Not enough demand to really build a business case on. But when you add those other markets, it all the sudden gets up to 16 flights per year on an Atlas V based vehicle, which could be as many as 40-50 flights per year on a smaller future RLV. Of course, at that flight rate, getting the ticket price down far enough that you really start catalyzing demand and getting into the breakthrough phase (say $1-5M per ticket) is entirely possible. One of the biggest holdups to private space transportation has been the lack of an elastic market big enough to justify a vehicle with a flight rate high enough to yield low enough costs to make a difference. This potentially changes that.


• Not only that, but a Sundancer is small enough that it might make a good payload to take out to L-1, or as a "mission module" attached to a capsule for long duration trips, or as a lunar surface cabin. Nautilus is a lot bigger and spacier, but at 50klb, it's way too heavy to move around easily. 19klb is much easier to take around and drop off where needed.


• If Bigelow can really pull off getting sufficient flight demand at $10M/ticket, through tapping additional markets, that makes a lot of other business plans easier to close, such as a lunar transportation company. I had always been assuming that you wouldn't get past the 2-3 flights per year demand range until you had the ticket price down in the single digit millions range. But if you could find governments that want to send people to do lunar research or prospecting, or whatever (or companies or research or non-profit organizations), the ticket price where you could get decent demand may well be in the $10-20M range, which brings that a whole heck of a lot closer to reality.

Anyway, that's all I have for now. It'll be a while before all the ramifications of this announcement sink in. There are a lot of things that could go wrong, but I can also see a lot of hope for the future. If Bigelow's plan works, it will have far greater effects on our status as a space-faring civilization than the Vision for Space Exploration will ever have.

Bravo, Mr Bigelow.

Lockheed/Bigelow Space Tourism Deal

Earlier this week when I posted a link to the Lockheed paper on man-rating Atlas V, I got an off-list comment from somebody to expect a major announcement from Lockheed this week. Well, we didn't have to wait too long. According to an article on NASASpaceflight.com, Lockheed Martin and Bigelow Aerospace have entered into a deal to investigate using the Atlas V for space tourism. The kicker is the market size--16 flights per year between crew/passengers and cargo. That could mean as many as 60-120 people flying to orbit *per year*.

The deal apparently covers finishing up some of the technical research into man-rating the Atlas V, as well as studies into the making the business case close, and probably also covering studies into ways to streamline their processes further to enable a flight rate as high as they're talking about (while also cutting costs to a point where they can offer a ticket price that enough people can afford to get the flight rate they want).

This is rather interesting, because I brought this topic up on the way down to work while carpooling with Ian and Pierce. I have a half-written blog post looking into the economics. My first read is that I'm skeptical they can make this work, however here are some things to chew on:

• Lockheed has the contract for the Orion capsule, which means that they can probably piggy-back a lot of their space tourism capsule work off of what they're doing for Orion. Also, if they happen to be able to field their Atlas V tourism vehicle before Orion, they might be able to make out like total bandits--netting billions in development funds for something that they can turn around and say "look, we have a cheaper, and better alternative that's already on the market, --go with us, and you could save lots of money". The upshot being even more flights on their Atlas V. I think this is potentially win-win-win for Lockheed.


• As LM has pointed out elsewhere a lot of the price hikes for Atlas V stem from the fact that they're only launching 2-4 of these per year. They have to cover all of their payroll costs, factory maintenance and upkeep costs, pad ops costs, etc but spread out over much fewer launches. At 2-4 flights per year, they're looking at $140M for their barebones Atlas V, while at 6-8 flights per year they were offering it initially for about $70M. At 20 flights per year, maybe they could cut the price down into the $35-50M range. At that point, the costs per person would be in the $5-10M range.


• Bigelow has stated time and again that he's not in the orbital hotel business. He expects to make most of his money off of building space stations for research, manufacturing, providing low-cost space programs to countries not traditionally thought of as having space programs, as well as orbital tourism. A lot of those other markets aren't as sensitive to cost per ticket as they are to reliability of access. 16 flights per year means that you have a ride to orbit about every 3 weeks or so, which while not perfect, makes many space-based research projects a lot more feasible. Frequent, reliable access to space is just as important as cheap access to space.

So, the burning question are: Can they pull this off? Can they get the price lown enough to open up a market? Will this have a positive or negative effect on the rest of alt.space? If a business case exists, can they actually succesfully execute on this? How will this effect the implementation for the rest of the Vision for Space Exploration? Will this end up being the Iridium/Teledesic boondoggle for this decade, or will it actually work out?

We live in interesting times. Strange things are definitely afoot at the Circle K.

I Get Ideas...

It's always a mixed emotion when you read a magazine article about a new technology that's now hitting the market that you had independently thought up 7 years ago. On the one hand there's the "Hot Dang! That idea really works?!? I am so Smart, I am so Smart, S-M-R-T!" reaction, followed almost immediately by "Darn. I wish I had followed through on that. That guy's going to make a lot of money."

I had just such a moment last month on the way up to Oregon to pick up my family. I was sitting in a magazine shop there in Sacramento, reading all the technology magazines to keep myself from going crazy during my multi-hour layover (you know you're bored when you're kicking yourself for not having brought the orbital mechanics book as "light reading"). I openned up what I think was Popular Mechanics or Popular Science, and there was an article in there about ultrasonic bone repair devices.

Back when I was 18, I was taking a health class at BYU (one of my last classes I had left in my undergraduate at the time). The teacher mentioned that bones are actually mildly piezoelectric--ie that every time you strain the bone by putting a load on it, it creates a small voltage across the bone. I had recently taken a materials class that had been discussing how corrosion works, and I realized that this piezoelectric effect might also be related electrochemically to how our bones pickup calcium. My thought was that the small induced current was likely taking the form of Calcium ions being pulled into the bone latice, kind of like how "Sea-crete" forms by pulling Calcium ions out of the ocean onto a charged metal latice. So, I figured that by stimulating a bone with ultrasound, you could put loads on it that would be enough to induce calcium acretion without being high enough to potentially damage a weakened bone. I figured it might also be a good way of dealing with at least some of the issues related to zero-G bone loss. Unfortunately, being 18, broke, taking 20 credit hours that semester (followed by 21 the next semester), I let the idea fall through the cracks as it were.

Now that I know that the invention itself actually works, it'd be interesting to see how close my simplified understanding of the process actually matches with reality.


On another "warped minds think alike" note, I noticed that the "space tourism" capsule that LM was pushing in their articles uses a dual-purpose LES/OMS system. Apparently I wasn't the only one who noticed that you don't actually need an OMS if you have to abort before orbit, but that if you don't need to abort, you don't need the LES. By placing the engines in the center of the capsule base, they greatly lower the required thrust of the escape system, because (as Henry pointed out), that force is driven by the separation force at transonic speeds, and that is mostly driven by the fact that you get a low pressure zone behind the capsule when it tries to separate (if you have engines around the outside, or up at the top). If you have engines or something in the middle that can fill that low-pressure bubble with high pressure gas, the thrust requirements end up going way down. It's a good idea, and not just because I independently came up with it.

Now I'm just wondering how long it is before LM decides to start offering capsules on all of the launches as an insurance policy against a launch failure. Even though they've had over 100 consecutive succesful launches, that still only puts their demonstrated reliability numbers in the 98% range at a 95% confidence interval. I wonder if they could build a "satellite recovery" capsule for less than they would save on launch insurance by having that capability...

Holy Furry Dinosaurs Batman!

One of the things I've noticed over the past year or two is that my view about the big aerospace primes has been slowly changing. I used to pick on Boeing and Lockheed and Northrup as being a bunch of screwups who couldn't make a cost-effective space transportation system to save their lives. I still do from time to time. But I think this isn't entirely fair, and that there have actually been a lot of signs that some of the higher-ups in these companies actually "get it" when it comes to commercial space transportation.

For instance, Northrup is one of the main sponsors for the X-Prize Cup this year. A subdivision of ATK is working with XCOR on developing a regen-cooled LOX/Methane engine potentially for use on the CEV. Both Boeing and Lockheed now have suggested using dry-launch architectures for NASA's VSE implementation, with propellant deliveries open to all competitors, to help promote the whole commercial transportation industry. Lockheed looks like it's funding some of the man-rating work for the Atlas V on their own dime, and may even be working on entering the space tourism market (my wild speculation based on the paper I wrote about yesterday). They're also doing work on cyrogenic propellant transfer which also looks like it might be internally funded.

It's really interesting to think what this means for the near-term future of the commercial space transportation industry, and particularly for "emergent space transportation companies" like SpaceX, Armadillo, MSS, and others. Unlike some commenters who only see evil conspiracies by the primes to snuff out competition, I wouldn't be surprised to see more examples of primes teaming up creatively with alt.space companies (and even some being acquired outright) over the next several years. These companies were once just as flexible, quick, and efficient as some of us would like to be, and they haven't forgotten everything. They have lots of very competent employees, and enough capital to actually accomplish fairly interesting things. The most interesting thing is that it looks like a lot of them really are trying to learn from alt.space's successes, and adapt.

I'm not sure where I'm going with this thought, but I just wanted to say something nice about the big guys, because we in the alt.space corner of the world are often way too quick to criticize, and slow to give praise where praise is due.

Interesting Article on Cryogenic Propellant Transfer

I was poking around at some of the other articles on that Lockheed page ,that I got sent a link to, and found some more interesting stuff. Once again, big caveat about hyperbole being used, but I still think that they make some really solid points. Particularly the section at the very bottom about Cryogenic Propellant Transfer. If you have the time, I'd seriously recommend poking through all these papers, particularly this one, and this one (which I'll comment on later).

Here's some thoughts, comments, and things I noticed on the technical side:

• This paper supports my point I've made here several times that once you have a good way to settle propellants, all of the other issues related to Zero-G propellant transfer go from being unknown tech-development projects, to straightforward engineering projects directly based on existing hardware and processes.


• I was wrong about the amount of settling force needed to make things manageable. I'd always used 0.001-0.01g as a conservative estimate. According to LM, they've flight proven that .0001g works, and they've flight demonstrated settling at as low as .00001g accelerations. That's only about 10 micro-gees!


• Even without Zero-Boiloff techniques, it's possible to keep the boiloff rate well below 1% per month with existing technology.

As I said, I'd seriously recommend reading the whole thing. The thing to remember, is that this is LOX/LH2 we're talking about--pretty much the toughest commonly used rocket propellant combination to work with. I had never realized that while the Centaur was in orbit, that they have ducted vents being used to settle the propellants continuously, and that they have over 100 flights worth of experience with this stuff. As they point out, every Centaur flight demonstrates on-orbit propellant transfer--to the RL-10 engines. Including chill-down, propellant acquisition, propellant mass guaging, etc.

Now, the architecture they suggest is a "Vehicle to Vehicle" fueling architecture--basically it doesn't include a propellant depot. Adding a depot would possibly require finding a non-propulsive settling route for the propellants, but would possibly simplify the remaining problems substantially. If the depot is manned, you could use remote piloting instead of fully Autonomous Rendezvou and Docking, you could add a small arm like the Canadarm Mini I suggested to allow you to berth modules instead of docking, which makes that even easier. And you could manually attach propellant transfer lines in a shirt-sleeve environment, which gets rid of the last complication.

There still is some work left to be done, but if anyone can honestly read these papers and not get the feeling that "this is a technology that is most of the way there, and not a long-shot bet at all", I'd be surprised. In fact, I'm going to make a prediction. I'll be so bold as to say that before a full CLV stack flies for the first time, there will have already been an on-orbit demonstration of cryogenic propellant transfer by a commercial company.

What do you guys think?

LM Atlas V Man Rating Paper

An anonymous commenter sent me a link to this paper that LM is presenting at the Space 2006 conference this weekend in San Jose. While the tone definitely has some marketing hyperbole to it (calling Atlas V a "high flight rate" system, etc), but it addresses some of the key issues brought up by ESAS. I don't have time to do a full analysis (I'm on my lunch break), but here's a summary:

• Factors of Safety: NASA Human Rating requirements (NASA Standards 8705.2A as well as NASA Standard 5001) call for a 1.4 Factor of Safety on most of the subsystems of the rocket. For an Atlas V 401, carrying a 20klb capsule, it turns out that Atlas V meets and exceeds this criteria, as most of the systems were designed for handling the limit loads for flights carrying SRBs, heavier payloads, etc. Now, I'd never design something with that thin of a margin, but they don't have to deal with high cycle fatigue issues (since the vehicle is expendable), and they also have flight data from over 100 flights to back up those design criteria and analyses.


• Abort Loads: Even with the single engine Centaur upper stage, they were able to come up with a trajectory that is sufficiently shaped to avoid exceeding the peak abort reentry G's laid out in 8705.2A, while only losing between 5-10% of their payload capacity. And nobody but NASA can figure out how to force the requirements of an ETO capsule bad enough to make it too heavy to loft on an Atlas V 401.


• Another interesting point is that Lockheed wants to implement a lot of the Emergency Detection System hardware to every flight, even unmanned flights, in order to build up more datapoints, and get more flight experience with it. I do believe there was a canard floating around that making all the changes in order to "manrate" Atlas V or Delta IV would make the normal versions "too expensive" for unmanned customers...Apparently Lockheed disagrees.

I could go on. There was some really interesting meat that is well worth reading for any company that wants to build crewed space transports. If Lockheed could do this, I bet that Boeing could also figure out how to make their vehicle meet NASA's official human rating rules without too much expense either. The Continual Employment Vehicle would have to be seriously Jenny-Craiged in order to launch on either of these vehicles, but there's a point at which you have to ask yourself: if existing vehicles are less expensive, require far less of an upfront investment, and actually meet NASA's own safety standards without having to be grandfathered in...what legitimate justification is still left for the Stick?

Oh, one final caveat. In all of these discussions about EELVs, I need to make clear, that even at high flight rates, I think these vehicles are too expensive in the long run. Cheaper than the Shaft and the Longfellow, sure, but still far too expensive for a sustainable space transportation infrastructure. However, once NASA has gotten out of the building/operating their own Earth-to-Orbit transportation business (you know, one of the selling points of the original VSE), and has made an architecture that can be launched using smaller vehicles, it makes it far easier for lower-cost commercial vehicles to eventually take the lead. If NASA were to adopt a drylaunch approach, and go with commercially available human, propellant, and cargo launches, it would be in a great position to benefit from continuous improvements in low-cost space transportation as they become available. Right now, even with Griffin's "we'll buy propellants from a depot to refuel EDS's if they become available" approach, NASA is locking itself into two vehicles which will be obsolete by the time they even enter service.

One Of The Stupidist Thing I've Ever Heard

Whichever Wunderkinden at NASA or the Russian Space Agency who thought it was a good idea to tell Ansari that she can't fly her native country's flag on the uniform that she paid for should be fired. Or at least sent to the NASA bureaucratic equivalence of Siberia. I think that "Reverend" Rick over at SFF put it best in an interview with Alan Boyle:

"It's the stupidest damn thing I've ever heard. We're missing a tremendous opportunity to deliver a message to the real Iranian people. She should wear the Iran flag on her suit, and our people should be proclaiming the fact that an Iranian woman, oppressed in her own country, can come here and make a fortune and spend it by pursuing her dream, enabled by an American company working with the Russians to fly her in space."

[Update: I had some additional commentary, but Rand called me out on what I said. I realized on rereading what I had originally written, that I had "turned on the vitriol hose" while thinking about too many annoying things simultaneously, and kinda lumped a lot of people with divergent views into one or two straman categories. I also realized that part of what I said was based on private conversations with people that I probably shouldn't have brought up in public. I apologize.]

Latest MSS Update

While blogging lately hasn't exactly been "light" by any stretch of the imagination (sleep? Who needs sleep?), commenting has been light, and people have been wondering why I haven't replied to some of the dozens of comments I've received over the past few weeks. Here's why:





You can read the whole thing here.

Solar System Ambassadors, Lunar Questers, and more

by Guest Blogger Ken

Almost missed this one! There's an Announcement of Opportunity over at JPL to sign up for the Solar System Ambassador program.

This is a neat program begun in 1997 that trains people from around the U.S. in basic Solar system science, and then asks that those so trained, having earned the title of Ambassador, to go into their communities and perform at least four outreach events in the next year, and each year thereafter to maintain their status. Here in North Texas we've been able to provide opportunities for SSAs to meet that requirement through NSS-NT outreach events. It's a win-win situation.

SSAs are fed a steady supply of JPL and NASA produced presentation materials, such that "JPL missions exploring Jupiter, Saturn, Mars, Asteroids, Comets, Earth, the Sun and the Universe now come together to expand the program's scope to the Solar System and beyond."

Acceptance of applications closes September 30th, so if you've been wondering how you can help bring space to your community here is a golden opportunity.

Another golden opportunity, also primarily for educators (of whatever stripe), is for Lunar Questers. NASA Ames is running a Lunar Research Station Design Challenge. It looks like there will be a tie-in with the MDRS as part of the proceedings. Registration looks like it also ends September 30th. Perhaps there's a Selenian Boondocker out there who is up to the challenge.

I also heard that the "Lunar Base Handbook" by Peter Eckart has a second edition coming out in the near future, so be sure to keep an eye open for that one. The first edition, published in 1999, is still one of what I consider the top references in the Lunar Library. It is one of the definitive works, how it can be better I don't know. We'll just have to wait and see.

While we're waiting, you might want to pick up a copy of "The Survival Imperative: Using Space to Protect Earth" by William E. Burrows. A few older readers may remember some of his prior works, such as "This New Ocean". I was lucky enough to see him speak at an NSS-NYC meeting back before I left for ISU. He spoke about the Alliance to Rescue Civilization, or ARC. This is a project that would put, in essence, a back-up hard drive of civilization on the Moon in event of global catastrophe, to hasten the return of civilization here on Earth afterwards. It's a simple and compelling idea. Which leads to my conjecture: How do we know there's not one up there already, say pre-Noachian?

The book would be a hard read for anyone prone to sensitivity and irrational fear. I'm only about a third of the way in and so far he has been laying out the many ways in which humanity could be done in. Not in any kind of fear-mongering way, but rather as a cold, rational laying out of the facts. His primary interest is big rocks from space, but he also explores all kinds of self-inflicted nastiness as well. The author has had access to a lot more resources than I, but everything he lays out jibes with what I know and I haven't found any faults. Even learned a few things.

It's not an easy work, but it is an important one. The intelligence that allows us to understand these risks also allows us to find ways to mitigate them. This can be an important part of why we step farther out into space, I can't wait to see how the author addresses this.

ESAS Issues Part One

The more I look at Section 6.4.4 of ESAS (Chapter 6 can be found here on the NASA website), the more I realize that the entire architecture pretty much hinges on the assumptions in this section. The reasoning in this section is pretty much *the* case for why we have to use a Heavy Lift Vehicle, and why using existing or near-term available launch capabilities isn't adequate for the lunar architecture. The problem is that in addition to my previous gripes, there are a lot of hidden, incorrect, assumptions in this part of the study that I think taint the results of the rest of the study.

Return of the Highlander Fallacy
The single biggest hidden assumption is a form of the "Highlander Fallacy". The assumption is that in their analysis, there is only one companies launcher used, launching out of one facility, that has a single pad. You can see very clearly from figure 6.19 (which I yoinked from their report) that they are envisioning a very sequential process:

Launch number two can't happen until after Launch number one has had it's pad prep, gone through all it's scrubs, and is succesfully off. This simplistic analysis breaks down really fast if you assume two or three launch providers, or two or three pads, or two or three sites (with the best being a combination of the above). Take the IMLEO requirements from ESAS, which come out to about 340klb (290klb from Ares V and 50klb from Ares I). If you tried to launch them all on one EELV, it really would be very difficult. If you could manage to break all the payloads up into stuff that could be launched on single-stick launchers (Delta IV Medium or Atlas V 401), it would take about 17 flights, which is way too many compared to the manufacturing and pad availability for either booster. But if you split it between the two, it comes back down to about 8-9 flights each. If you use a few Delta IV Heavy launches for the big pieces (the EDS stage, the Lander, and the CEV), it gets down into an even more reasonable range of launches.

There are a couple of issues that come up:

• It is a really bad thing that pretty much all of our nation's launch capacity into non-polar orbits is located within a few miles of each other in a state like Florida where weather related scrubs are more common than almost anywhere else in the country. If you have a weather related scrub for one vehicle, you'll probably have to scrub the other too.


• Any non-polar commercial satellite that wants to be launched by either of these two boosters will have to fight for a position in the queue.


• Each factory was designed with the capacity to produce something like 20+ EELV cores per year. Whether that can be increased by adding extra shifts (or whether they were already planning on double shifting) remains to be seen.


However, there are a couple of additional insights that are interesting:

• The entire cost for fielding both EELVs, including building the factories, and one or two pads each, as well as doing a cleansheet design, was less than $2.5B total. Adding an extra pad, if the demand was there, or adding extra factory capacity, could likely be handled at some small fraction of that cost (maybe something like $1B).


• If SpaceX works out, their Kwajelein and planned Cape Canaveral sites would make the whole situation even easier. With three providers, two sites, and at least one pad per provider per site, the odds of "Loss of Mission" go way, way down.


• At the kind of flights rates possibly envisioned here, the DoD could drop it's subsidy of the two boosters, and the prices for all of them would go way, way down.

Anyhow, I have to run to work now, but when I get a chance, I'll talk some more about some of the problems with this troublesome section.

Anousheh Ansari's Blog

Robin Snelson just sent me a link to Anousheh Ansari's Blog. I figured I would pass it on to those who haven't seen it yet. Her helping fund part of the X-Prize has made a big difference in the emerging space transportation industry, and I'm glad that she's getting a chance to go to orbit. I hope someday we can get a low-enough-cost lunar transportation system to allow for lunar flybys or lunar landings at a ticket price comparable to current Soyuz flights to ISS. It isn't unreasonable, and may well happen sooner than most think.

I Know I'm Flogging a Dead Horse....

...but this post over on Burchismo was pretty much spot-on. A few excerpts:

It wouldn't have been that much more difficult to build a reusable lunar orbit-surface-orbit shuttle and leave it in lunar orbit after each mission. But NASA has an irrational fear of on-orbit refueling. For some reason that the space commentariat can't identify, they won't develop or test the technologies necessary to do it, and so they can always say it's untested and therefore too dangerous. This from the same outfit who designed and implemented the shuttle system so that it's first flight HAD to be manned. Huh? The same goes for the lunar transit step. A reusable Earth-Moon taxi is NOT beyond our technical competence. But NASA won't take the refueling step. So the program is designed in a way that makes it too politically easy to declare victory and quit at any point after a lunar landing or two or three with the new system has been achieved.

Regarding the Ares V HLV:

But it begs the question of the need for and economics of such a brute. The Russians couldn't make it pay with their equivalent, the long-dead Energia super-booster that only flew a few times and has now gone the way of the Saturn V. The demand for such heavy lift capacity is very, very small. In fact, it's only real because NASA chooses to make it so with the Orion mission design.

Ken was putting together a blog post that he never finished that had a rather informative quote from Scott Horowitz of NASA ESMD that illustrates rather clearly the biases and assumptions that helped them justify the decision they wanted all along:

The cost of breaking the exploration missions into numerous smaller pieces to accommodate a smaller launch vehicle is cost prohibitive. Each smaller element will have to become a complete spacecraft on orbit while performing an automated rendezvous and docking and be burdened with all the systems required to survive and operate in space including power systems, thermal control systems, propulsion systems, guidance navigation and control systems, docking systems, etc. Then there is the cost of the infrastructure required to support the surge rates needed for multiple launches of smaller launch vehicles that would be required during a lunar or Mars campaign. This combined with all of the associated operational costs make the use of smaller launch vehicles for exploration missions cost prohibitive. Add to that the impact on mission reliability as a result of performing so many launches and associated on-orbit assembly operations and one quickly realizes that the chances of accomplishing multiple moon or Mars missions using smaller launch vehicles is slim to none.

As we were driving down to Space Access, James Robertson was with us reading through some of the ESAS related documentation (or at least I think it was ESAS), especially the part leading up to the preference for the "1.5 Launch Architecture". I'm emailing him to see if he can find the relevant section again (because I sure couldn't find hardly any real substantiative discussion of that critical choice in the ESAS documents I skimmed tonight), but the gist of it was that the way they were treating mission reliability for multiple launch architectures was completely broken. They assumed that if you had a multi-launch architecture, that if a single launch failed, that the whole mission would be completely lost, as though all the hardware that you succesfully orbitted was somehow going to disappear instantaneously if you have a single launch accident.

[Updated Sept 12: James pointed me to the section, it's 6.4.4. It's worse and more garbled than even I remembered. Basically, they assume that all the assembly is going to be done autonomously (in spite of the fact that the US has little experience with Autonomous Rendezvous and Docking), and that any failed rendezvous event, or any delay in propellant delivery past the initial planned departure date, or any failed launch event means that the entire mission is lost. Now Rand points out that this may be valid for a Mars mission. But do you really think that by the time we do a manned mars mission that we won't have some sort of on-orbit infrastructure? That we won't have propellant depots that act like an UPS system for your computer, providing enough capacity to deal with temporary bumps in the supply chain? That we won't have the ability to "redock" components if the AR&D system doesn't work right the first time? Their analysis is valid if you accept all of their silly assumptions, but if you actually think it through, you come to completely different conclusions. ]

This is echoed in the last part of Scott's quote. If you assume a more sensible architecture, where instead of trying to make a whole bunch of mini-spacecraft and mini-tanks, and assembling it all together at some spacedock, that you instead just do a simple drylaunch approach like several of us have mentioned, that concern goes out the window. Most of the launches in a drylaunch architecture are non-mission critical, because they are propellant. Even with the worst realistic boiloff rates, a full month worth of delay wouldn't be an issue even for LH2 boiloff. Losing any propellant tanking launch is at worst going to delay your departure date. If you use a buffer/capacitor in the form of a propellant depot, you can even isolate your mission reliability from the launcher reliability further. And, if you use a reusable transfer stage, and reusable lander, and have a small fleet of three to four of each (launched over a year or two space), then even the accidental loss on launch of any given part of the hardware, the impact on the overall system is marginal.

So yeah, if you make unrealistically dumb assumptions about how a multi-launch architecture should be done, you can "prove" that a politically convenient Shuttle-Derived launch architecture is superior. Data never lies, but if you torture it long enough, you can get it to confess anything you want.

Upcoming Interviews

A good friend of ours, Bob Steinke, recently announced that he had started a new aerospace company called SpeedUp. We were over visiting with him this evening, and I asked if I could do an interview of him for the blog, since I'm one of the few people who have heard what he's up to. He said yes, but with my work schedule next week, I'm not 100% positive how soon I'll be posting it. I just wanted to give some advanced notice. I've been toying with the idea of starting a series of interviews with some of the leaders of various emerging space companies, and I figure that if I actually say something about it, loyal readers will nag me until I actually do it...

Lamenting the Tyranny of Low Expectations

I was thinking a bit about an idea I've heard Mark Whittington bring up repeatedly over the last several months over on his blog, and in comments here and elsewhere. Basically the idea he keeps putting forward is that the best way to involve private industry in the return to the Moon is for NASA to carry out their plans based on ESAS, build a base on the Moon, and then have a COTS like program for inviting private companies to resupply that base.

Mark's plan might just work, but if it does, it will be another tragic waste of billions of dollars and decades worth of time. Look at COTS itself for a moment. The amount of money that NASA is providing for development is actually fairly decent for two teams. But the total amount of demand they'll be providing is only a couple of launches per year. When you think about how many billion dollars have been spent on the Shuttle and ISS over my lifetime, it comes out to well over $100B in 2006 dollars. Maybe even as high as $150B in current dollars. Think what would've happened if NASA had taken seriously the part in the very legislation that created it that states that NASA is to "seek and encourage, to the maximum extent possible, the fullest commercial use of space."

If NASA had spent even a tiny fraction of the amount it has spent on the Shuttle program instead on actively promoting and enabling the creation of a robust private space transportation industry, think where we would be today. NASA might be able to purchase tickets to send hundreds of astronauts per year into space, send many times as many space probes out every year, and would have had a robust transportation infrastructure to utilize for its exploration purposes. Both manned and unmanned exploration would be flourishing, very possibly on less money per year then they are receiving today. Heck, with a real thriving space transportation industry, private entities like National Geographic, or Nature, or Scientific American, could have likely sent out some of their own missions or expeditions by now. There would be no talk about a "gap" in US manned space transport capabilities because there would be so many customers and providers in a robust and competitive industry that such talk would be as ludicrase as a "gap" in US manned air travel. Instead, NASA took the route of political expediency. They decided that keeping team Apollo together, and keeping high-tech jobs in as many congressional districts as possible was more important than actually following the mandate given in their authorization bill. They decided that rather than encouraging and unleashing private enterprise to find the best ways (note the plural) of accessing space, that they would design the US "Space Transportation System" that was going to be the way that everything in the US got launched into space.

26 years later, we're now supposed to be estatic and cheering about NASA providing demand for a half dozen small payload deliveries per year? We're supposed to giddily await the day when NASA's small 4-man outpost on the moon needs a flight or two per year of food and toiletpaper, and decided to throw a scrap to the private sector?

The fact that COTS is pretty much the best attempt NASA has done in my lifetime to pay any heed to the "seek and encourage, to the maximum extent possible, the fullest commercial use of space" part of its authorization legislation is sad. COTS is a step in the right direction, but looking back at what could've and should've been and comparing it to what we've got, it's hard not to feel seriously cheated.

Talk about the tyranny of low expectations.

Lunar Library v2.0

by Guest Blogger Ken

Well, this round of updating the catalog of the Lunar Library was a little more difficult than in past semi-annual updates, as the guys over at Out of the Cradle had an idea on how to make it more useful. By using the blog post function we could create an ongoing list of things Lunar and when they were produced. While difficult to implement given the volume of materials in the Lunar Library, updating it as I find new titles will be a snap.

This time it's called v2.0 because it represents a major improvement in its utility. The original, back on the Space Frontier Foundation's 'Space Arena Board'/né 'Return to the Moon' BBS, was just the text list that I kept of the titles. The main purpose of the list was in the event of a fire I would have an offsite archive of all the works that would need to be replaced. I also hoped it would be of utility to other people interested in the Moon who might not know what kinds of titles are available to sate their curiosity. The last version there was published the end of 2004.

After the flame-out of the SFF board, Clark Lindsey over at Hobbyspace.com was kind enough to host it online in the interim, and introduced hyper-text links from the top menu.

This time around it has been further subdivided, so that particular areas of interest can be more easily explored. The full index is:

Moonbases
Selenography
Selenology
Cultura Lunaris
Apollo
Moon Fiction

Space Biz
Space Law

Big Rocks From Space Fact/Fiction

High Frontier
-Biologics
-Facilities/Infrastructure
-Navigation
-EML1
-Resources
-Settlements/Habitats
High Frontier Fiction

Youth Apollo
Youth Moon Fact
Youth Moon Fiction
Youth High Frontier Fact
Youth High Frontier Fiction

Fun & Games

Each individual work has gotten upgrades consisting of, where available, an Amazon.com link to check out reviews, the publisher's website to see what they have to say about it, the text on-line, and an Out of the Cradle review link.

There were some definite surprises in the on-line texts that were available, such as the entire issue of Science magazine published on my birthday in 1970 that covered the first round of research on the Apollo samples. Kudos to them for that one. Also the space plants, Apogee Wheat, that I picked up some seeds for during a NASA Academy visit to Cape Canaveral, where they have that sealed plant room NASA uses for hydroponic studies. Lot's of educator appropriate materials and links, like a phenomenal high school level work on how the body functions in space that is now an on-line website (my original hard-copy is spiral bound). Project Gutenberg offers the text of many of the early science fiction works.

There are going to be a few layout changes, to give it a more Moon-ish appearance, and the index function is going to be reworked, but I wanted to give readers of the Selenian Boondocks a special sneak peek at it before the final version is rolled out.

Lunar Library v2.0

Enjoy!

P.S. I'm still mulling over the idea of the creation of a university-level "Lunar Academy" for which this library would provide the core research materials. Ultimately, though, it's destined for the International Space University Lunar campus. Good thing I've finished my part, as now I've got to get an abstract together for the ISU Symposium in February, "Why the Moon?"

Yeah, I'll tell you why the Moon...

K

Aerobraking vs Propulsive Braking

A lot of commenters in the last thread asked why I like aerobraking over propulsive braking for return to LEO. The answer is simple. Propulsive braking requires just as much delta-V going out as it does coming in. Which gives you a whopping 8.4km/s end-to-end delta-V requirement. That's practically the same delta-V range as an SSTO vehicle. The K-1 upper stage couldn't even fly its own weight (empty!) to lunar orbit and back using propulsive breaking. I checked the numbers assuming something like LOX/subcooled-propane, since that mixture tends to get 20s better Isp, and has the same relative volumes as LOX-Kerosene, so the K-1 OV could conceivably be upgraded to use it, possibly just require requalification, with few if any physical modifications to the stage. Problem is that the most payload I'm getting is in the 1-4 tons to Lunar Orbit range, based on a 150 ton stage in LEO with about 131.5 tons of propellant. That really sucks. Even if LEO prices got ridiculously cheap (say $50/lb in LEO), then you're still talking about $7000/lb in lunar orbit. If you use more realistic numbers, it climbs to prices that make Pegasus and the Shuttle look economical. It's a nonstarter.

Now, you could switch to LOX/LH2, but now you're talking about a whole new vehicle, probably with a lot worse of a drymass. The numbers for that actually look like they might work, but you've now pigeon-holed yourself into a single-propellant combination, that just happens to have the worst bulk density, worst boiloff issues, etc. And you don't even get as good of performance as a LOX/Kero stage with aerobraking.

Maybe someday in the future where you have massive amounts of ISRU derived propellants available in lunar orbit, you might just be able to get such a system to work, but why not just figure out how to aerobrake. Is it really that much tougher? I don't think so. Not by a longshot. Aerobraking is one of those technologies whose payoff-to-risk ratio is so high for longterm space development, that you may as well consider it a neccessity.

More Jonny Bloggin'

I'm at home sick today, taking care of a little boy with a fever, who is now napping. So I figured now would be a good time to put up some of the pictures Tiff took during her month in Oregon with her family.


This is Jonny on the steps outside of the Portland, Oregon LDS temple. That's where Tiff any I got married back on August 23, 2003. Tiff's little brother Steven was getting married there on the 5th.


Steve and his wife Carly are, of course, the ones in the foreground on the left. Behind them is Brady on the left (holding Liana), then Randy in the maroon shirt. To the right of Steve and Carly on the front row are Tiff's parents, Dan and Sue Cragun. Sue is holding Naomi. Behind them are Naomi and Liana's parents, Michael and Rosie, with Rosie holding their youngest, Rebeckah. Rosie is from Cagayan de Oro, Philippines. To the right of Tiff's parents is Tiff's grandma Margaret, holding Jonny. Then there's my Tiffy to her right. Behind Tiff and grandma Margaret are David and Jenny holding their boy Caleb. And on the far right are James and Nikki. James and Nikki got married in the same place on the 26th, while I was up there. Well, that's the Cragun clan.


This is another picture of Tiff's youngest brother, Brady. I think the gal he's with is one of Carly's sisters, there at Steve and Carly's reception. Anyone guess which side of the family Jonny got his curls from?


This is Jonny being a non-conformist.


Tiff's Dad works at the local newspaper, the Register-Guard. Their family is way into crossword puzzles. Michael and his family are probably in Cuba now. He works for the state department as an embassy worker of some sort. They're going to be working in our un-embassy embassy thingie there in Havana for the next two years. They were in DC for training for most of this year, and the whole news about Castro going to the hospital hit while they were driving cross-country from DC to Oregon. I told Michael "may you live in interesting times." I'm not sure if he appreciated my sense of humor.


This is one silly little boy doing his own dance move. He loves dancing, any time there's music. Now that he's home, he's gained a taste for Creedence Clearwater Revival...can't blame him.


Jonny on the Tramp with David and Naomi. Jonny misses playing with his three cousins. It's a lot quieter around here.


Here's the dunes at a lake near the ocean just south of Florrence, Oregon. The drive down was beautiful, and the weather was somewhere around 60 degrees. One of these days we need to get a rocket company up in Oregon so I can live somewhere that I like while still being able to play with hot flamey stuff. Knowing my luck though, if there were a rocket company in Oregon, it'd be out in Bend or in the eastern desert area.




Kids grow up so fast these days...

K-1 Orbital Vehicle As A LTV?

I was doing some thinking, planning on writing an article talking about why the Orion crew capsule's basic design philiosophy was flawed, when I came upon a much more interesting idea. Basically, I realized that the upper stage of RocketplaneKistler's K-1 vehicle (the Orbital Vehicle or OV for short), could actually make a pretty darned good Lunar Transport Vehicle.

How I got on this Tangent
Here's how I got off on such a weird tangent. When thinking about how the CEV is being designed, I realized that a lot of their problems come from the fact that they're making similar mistakes to what they did with the shuttle. Instead of designing a "space truck", and then designing a "camper" to go with it, they decided to make it a cross between a "space big-rig" and a space "winnebago" and a "space research facility". In other words, they tried to not only cram in a heavy cargo lift capacity, and a pilot/copilot, but they also crammed in a long-duration space hotel (capable of housing 7 people for a few weeks), with research facilities, and several other things. Then they tried to add a bunch of cross-range to it, and when you're all done you get the monstrosity known as the Shuttle.

Quick digression: Just in case you've sucked up the groupthink, Shuttle's problem wasn't mixing crew and cargo. If they had designed it as a crewed cargo delivery vehicle, where the crew was a pilot and copilot, and the crew accomodations were only for short durations, the vehicle would have been many times smaller. Even with the 60klb cargo capacity, if they had cut the crew requirement to two, and used fairly spartan crew facilities, the whole thing would've likely been half as big as it ended up being, which would have made the whole thing a lot easier to work with in spite of all its other flaws. With that kind of a setup, they could have added a "camper module" inside the payload bay (like many of the things SpaceHab has built) for when they needed longer duration habitation capabilities, or research facilities. Trying to cram as much as they did into the basic vehicle was a big part of the problem.

There's absolutely nothing wrong with having a crew member or two on a vehicle. They really don't add that much weight to a reusable vehicle, and add a whole bunch of flexibility. Ok, that's enough on that rant.

Going back to the CEV, they're making some of the same mistakes. Instead of trying to make the CEV modular, so that you add capabilities as you need them, they're once again trying to design a winnebago, and then go back and slim it down for other applications.

So, I was thinking about how I would adapt a commercial earth-to-orbit capsule, like SpaceX's Dragon, so that it could have some of the same general capabilities as the CEV, without being such a bloated, expensive monstrosity. I started thinking about adding a mission module like CSI proposed with their Lunar Express idea that they unveiled back at the Return to the Moon conference last year. Basically, you dock the Dragon capsule to a module that would have longer duration habitation facilities, more room, etc, and then you could use an upper stage to send it to the moon. All it would need would be a slightly beefier heat shield, and you're off to the races (Yes, that is a development project, but one that both we and the Russians have done previously. 30 years ago. I think we can figure it out again.)

So I started thinking about doing something similar with RpK's Orbital Vehicle, when I started crunching numbers...

More Than One Way Home
The simplest and most typical method used for returning a vehicle from lunar orbit is to do a direct return. Basically you do a burn in lunar orbit that slows you down enough that your perigee intersects with the earth's atmosphere, and then you use the earth's atmosphere to slow you all the way down until you're slow enough for your recover system (usually parachutes) to take over. There are some variations on the theme, but the vast majority of missions planned, executed, or even dreamt-up use this technique. The problem with this technique is that it is rather demanding on your TPS. You're coming in at about 11km/s (instead of the ~7.2km/s from LEO), which means you have over twice the kinetic energy to bleed off. You end up getting much higher peak heating loads and G's than from a nominal LEO reentry. Kistler's vehicle uses a radiatively cooled TPS system, much like the Shuttle, which includes a combination of carbon-carbon tiles, and ceramic blankets. These heat shields basically reach a thermal equillibrium where the amount of heat being pumped into the shield is ballanced by the amount reradiated outward from the shield. The problem is that if you greatly increase the heat flux in, the shield has to get hotter to reach thermal equillibrium. With a standard direct return from lunar orbit, it's questionable that a tile-based system like the K-1's would work very well. It might just have that much margin (after all thermal radiation goes with temperature in Kelvin to the 4th power, so it might not need to get that much hotter to reach thermal equillibrium...but proving that out would not be cheap).

After thinking through that, I was just about to give up on the idea, when I realized that the direct return isn't the only, or even the preferred way to come back from lunar orbit, especially if you have a reusable transfer vehicle. A much better, and more workable method would be to use a combination of aerobraking and propulsive braking to return the OV from lunar orbit to LEO, and then continue from there to earth's surface. For aerobraking, since you're trying to bleed off less velocity, you end up targetting a higher (and hence thinner) part of the atmosphere than you do with a direct return. It turns out that the peak heating loads and total heat loads are quite similar for aerobraking into LEO from a lunar return trajectory as compared to a return from LEO to earth's surface. Basically, by using aerobraking, you get to split your reentry into two phases, neither of which is particularly worse on the vehicle than a nominal reentry, and with as much time as you want between the two. This means that you can let your vehicle cool down between those phases, you can inspect your heat shield for damage or wear, or you can dock to an orbital facility or another vehicle to transfer crew or cargo. Also, this means that you might not have to do anywhere near as much requalification of the TPS design for the OV--you might even be able to use a "stock" OV for the mission.

Aerobraking Challenges
Now, aerobraking is a bit tricky. While we've done a lot of aerocapture, and a lot of multi-pass aerobraking (particularly for space probes going to Mars for example), we haven't got a lot of experience with "single-pass" aerobraking. Let me explain a little bit first. "Aerocapture" is when you have some incoming vehicle or probe that isn't actually in orbit around the target planet, which then uses the target planet's atmosphere to slow it down enough that it enters an elliptical orbit around that planet. This doesn't take a huge amount of delta-V, and so it can be done at fairly high altitudes, low heating rates, and low stresses. "Multi-pass Aerobraking" is using several passes through the upper atmosphere of the target planet (once you're in an elliptical orbit around the planet) to slowly drop your apogee until you're in a nearly circular low-orbit around the target planet. You do need a tiny bit of a circularization burn to bring your perigee back up at the end, but if you're patient enough, and can take enough passes, that propellant requirement goes way down. With single pass aerobraking, you try to bleed off just enough energy to lower your apogee to your target orbital altitude, all in a single pass, without lowering it so far that you end up accidentally reentering the target planet.

It's that last part that's the kicker. If you hit a part of the atmosphere that's a little too dense, your apogee can drop into the atmosphere, and then it's all downhill from there. If your vehicle isn't capable of taking a reentry, you're toast. If it is capable of taking reentry, you're likely to end up with a very hot, emergency landing somewhere completely unexpected. Neither of those is particularly good. In order to avoid that, you need to have fairly detailed information of the density of the upper atmosphere, and have good control of your vehicle during the maneuver. Not impossible, but dicey.

The reason why you really want to do single-pass reentry, in-spite of it being more difficult, is that it cuts dramatically down on the duration of the return flight. A return from lunar orbit usually takes like 3 days. With multi-pass aerobraking, you could end up taking another 2-3 weeks or more as you slowly keep dropping your perigee lower and lower. For humans or sensitive equipment, having to pass through the van Allen belts repeatedly is a major drawback. Also longer duration flights require more supplies, more food, etc.

So, how can you lower the risk of single-pass aerobraking? By beating the problem with a "delta-V" stick. Basically, if you keep a fairly beefy propellant reserve (say ~750 m/s worth), then if you hit a little too hard, you can do an engine firing to bring your apogee back up above the atmosphere, and if you hit it too soft, you can either come back for another pass (if you're close enough that your second pass will come up soon enough), or you can do a retro burn to lower your apogee the rest of the way. Now, whether that 750m/s is enough will depend quite a bit on how well we figure out the aerobraking in the first place. If we have good enough data about the atmosphere, 250m/s might be sufficient. I imagine that with a good star-tracker/GPS fix right before atmospheric interface, and with a good IMU, the vehicle computer can probably recalculate the apogee in real time, and let the pilot know (or adjust itself if it's unpiloted) if adjustments are needed. For this discussion, we'll use the 750m/s for reserve, and 250m/s for raising the perigee at the end of the breaking maneuver, but these numbers need more research before they can be considered gospel truth.

On-Orbit Refueling
The one other assumption in this plan is that there is a way to do on-orbit refueling. As per my previous discussions, this doesn't necessarily imply that you need a propellant depot to do this. Propellant transfer could be done by docking/berthing the fueler to the K-1 OV, then spinning the two like a baton to settle the propellants. Or it could be done using a non-depot station, with two or more docking/berthing ports. Just dock the OV to one port, have quick disconnects inside, dock the fueler to the other port, and then manually run plumbing runs and pumps between the two. Or you could use a depot. Regardless of how it's done, this idea does require on-orbit refueling before it can be done. Once you see the numbers I've run however, you'll see why I think this is a good way of approaching things (for NASA, or even for a privately funded project). The number of launches needed to refuel an OV will be rather large (about a dozen Falcon 9 flights, or about 30 K-1 flights, or even more of a smaller RLV), but in my opinion, that's a good thing. Higher flight rates will drive prices down, and flying more often tends to help you up the learning curve faster. With a bulk buy in that size, I'd be surprised if you couldn't get the price down as low as $1k/lb or less. That's still over $250M for a translunar flight, but that's less than the estimate cost of a single Ares I launch (estimated at $280M)!

Running the Numbers
Ok, here's what I found when running the numbers. Due to the weird "Return To Launch Site" maneuver that the K-1's first stage does, the upper stage only gets about 1.5km/s of it's orbital insertion velocity from the first stage, and has to provide the rest itself. What that means is that the K-1 upper stage (the OV) is a very high performance stage. From the Kistler website, and an AIAA article that I found, the relevant stats are:

• 290,000lb fully loaded without payload


• 348s Isp with 395,000lbf from their main engine


• 27,000lb dry mass (according to the AIAA article)

That comes out to about 8.5km/s of Delta-V from the stage. However, if you're using aerobraking, the most delta-V you need for a round trip is about 6.2km/s, which means that the K-1 OV can actually push a lot more than 10klb to lunar orbit and back. Here's a few sets of numbers I got (email me for a copy of the Excel spreadsheet I used):

• If you want to carry the cargo all the way to lunar orbit and back (leaving nothing behind), you can carry 24klb of payload there and back. If this were say a lunar tour group, you could probably carry 5-10 passengers and 1-2 crew (depending on how much space you needed/wanted per person).


• If the vehicle is flying unmanned, and drops all of it's cargo off in lunar orbit, it can deliver 51klb of payload in lunar orbit. This is enough capacity to deliver a Nautilus Module to lunar orbit (even easier if you want it in L-1 instead.


• If you posit a 10klb "crew module", you can still deliver 30klb to lunar orbit while bringing the 10klb module back to LEO. This is enough for 2-4 people and a small reusable 2-4 seat lander.


• If you posit a 6klb "crew module", you can deliver 38.5klb to lunar orbit, while bringing the crew module home. This is probably sufficient for a 2-3 person crew, and a 2-3 person reusable lander.

Not too shabby all in all. The most surprising thing I found was when I compared the K-1 OV to NASA's EDS stage. Now, admittedly there are a lot of numbers floating around for the various parts of the ESAS architecture, and it's hard to tell what the currently accurate numbers are. While I understand NASA not wanting to post numbers while the design is still in flux, it makes it a bit harder to do valid critiques. Some numbers I've seen put the fully fueled stack in LEO at about 374klb, with about 147klb of that being the CEV+LSAM stack. If that is the case, and assuming a 455s Isp out of the J-2X on the EDS, that gives you about 3050-3100m/s of delta-V, which is just about right for a Trans Lunar Injection (Apollo numbers and most other numbers I've seen come in around 3050 m/s). Unfortunately, these numbers are confusing because the NASA website claims that the Ares V is capable of putting 290klb into LEO, which would mean that the Shaft either is putting up 84klb, or these numbers are obsolete. NASA's site also claims about 143klb for the CEV/LSAM stack. Based on NASA's numbers, the EDS may impart as little as 2800m/s of the TLI burn, with the LSAM taking up the rest of the slack.

So, the current EDS is capable of giving the stack somewhere between 2800-3100m/s of Delta-V. It turns out that a fully fueled K-1 OV can give the stack anywhere from 2950-3050m/s of Delta-V (depending on how much propellant you assume for your aerobraking margin). Which means that in the absolute best case (for ESAS), the two are almost identical, but in the worst case, the K-1 OV actually provides more total impulse to the CEV+LSAM stack by over 300m/s.

Now, I'm not suggesting that NASA should fund this instead of Ares V and EDS (though one really starts wondering what the advantage of going that route would be), just trying to point out how capable of a vehicle the K-1 would be.

Drawbacks
There are a few drawbacks to using the OV as a lunar transfer vehicle. First off, it requires a lot of propellants for the job--almost twice as much as the EDS stage would by weight (but much less by volume due to the much higher density of Kerosene than Hydrogen). This would require a lot of propellant delivery flights (12 Falcon 9 flights at least, or 30 K-1 flights). While that's a lot of demand, and will drive the flight rates and reliability up for the vehicle supplying the propellant, while simultaneously dropping prices, that's also a lot of logistics one has to handle. Even at one flight per week, you're talking at least 3 months for the Falcon 9 fueled vehicle, or 6 months for the K-1 fueled vehicle. While that's comparable to the expected flight rate for the ESAS stack, that's still kind of low. If RpK were to build a few additional airframes (say a fleet of 5), you could possibly cut that down to more reasonable times, but that would require more people to process, and a much higher up front capital investment. SpaceX probably can't ramp the Falcon 9 flight rate up much higher than 1 flight per week due to their reusability scheme for the system. And, it may take a while for other competitors with higher flight rates to hit the market. So in the near term, refueling the OV on orbit (once it actually exists) will be a non-trivial task.

More importantly, two technologies still need some work before this can be done--on-orbit transfer and storage of propellants (particularly LOX, the kerosene should be pretty easy in comparison), and aerobraking. We know a lot about aerobraking, and the precision, and advanced knowledge of the atmosphere needed to do this right aren't that much harder than what is needed for a lunar return (with those you face the same issues--hit too fast and you burn up or go squish, hit to slow and you bounce), but this is an area where some low-cost demonstrators would be in order. RpK could probably do those internally (or with the help of a private consortium) for not too much if they can actually get K-1 built and flying. So, while there are technological obstacles, they aren't insurmountable.

The most obvious problem however is that K-1 doesn't exist yet, and has never flown yet. It's partially built, and it looks like RpK has enough money being promised that they could just pull it off, but it's a big project, and the team doesn't have much of a trackrecord yet for actually flying things. Until they've flown something, all of this is just fun speculations.

Additional Details
Now for details. If the OV that's being used for lunar operations is only intended for exo-atmospheric use, it might be worthwhile to remove the airbags and parachute. Kistler was following an approach of making things modular so they could be easily replaceable, but I'm not sure if they've made it so modular that you could remove or reinstall those on-orbit. If you can that'd be great (and if they can tweak the design to allow for that without costing too much extra weight, that'd also be good). The parachute plus airbags probably weigh in the 3000lb range (based on historical comparisons). With those removed, you'd have more than enough mass to have a docking interface, some solar panels, radiators, star trackets, and the plumbing interfaces for refueling. Add a Canadarm Mini, and you're off to the races! The modular design of the K-1 may actual make doing that relatively straight forward, since the design is meant to have it's payload bay swapped out depending on the mission. That would require some work, but the modularity they've built in will make it easier.

Crew/Passenger facilities for long duration flights also require both space and development. The larger of the two standard payload bays that Kistler has is about 3.4m in diameter by about 5.6m wide. That's a fairly decent size, almost 50 cubic meters of space, which is almost 4 times as much space as the combined CSM and LEM from Apollo. That is about 2.5 times smaller than an ISS module. So, while it's more spacious than what was used for Apollo for three people, it may be a bit cramped for say a 12 person tourist flight. There are a couple of ways of dealing with this, such as having an inflatable extension, or making the lunar payload bay version bigger (though that would require requalifying the aerobraking dynamics), or having a temporary extension.

Larger payloads like lunar landers would likely need to be docked externally (especially if the internal volume is being used for crews). This shouldn't be too hard, so long as they're left in lunar orbit before return. Anything that is outside of the OV moldline when it aerobrakes would either need it's own TPS (and would require requalifying the whole vehicle for flying with that external payload), or would get really toasty fast.

Anyhow, there's more details that would need work, but the overall concept has some merit. What do you all think?