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12:59 am
April 23, 2010
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KellyJ
| | Australia | |
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Hi guys,
Just wondering if anyone has read the book "The Rocket Company" by Stiennon, Hoerr, Birkholz. I have just finished it, and really enjoyed it. It seemed to me to be an ideal mission architecture for something like an open source project. I know the general consensus here is for a hybrid rocket, but just thinking about the difficulties of a hybrid vs a design like this that is more conventional.
Basically it uses two stages, the first stage is a 'pop-up' booster which goes vertically upwards to over 100,000 ft. The second stage then goes to LEO with a 5000lb payload. Both stages are fully reusable and manned. Using current engineering standards for structures and propulsion means that all the previous knowledge can be built on.
Interested to hear any thoughts about it!
(http://www.aiaa.org/content.cf…..mp;id=1280)
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6:57 am
April 23, 2010
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Luke Maurits
| | Adelaide, Australia | |
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I haven't read that book, but it looks like a great one for people involved in CSTART to read. Thanks for the reference!
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Main CLLARE workgroups: Mission Planning, Navigation and Guidance. I do maths, physics, C, Python and Java.
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11:45 am
April 23, 2010
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J. Simmons
| | Dayton, OH, USA | |
| Member | posts 46 | |
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I am reading that right now, and so far I am enjoying it. After I finish it, I may have to take a few minutes to look at the "math" of their launcher. I am particluarly intrigued by the business model (sell vehicles to operators, instead of building vehicles to operate).
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Founder Mach 30, Inc. and Friend of CSTART
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5:36 am
May 18, 2010
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brandonwillis33
| | United States | |
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Really! Is that really nice book. I will start reading it today.
hockey sticks
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7:51 pm
May 18, 2010
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KellyJ
| | Australia | |
| Member | posts 15 | |
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Brandon,
Yes it is a very interesting book. I think adopting that model would be perfect for CLLARE as it solves all the confusion about what the design is. It also gives a path forwards to actually get investors and people to build the hardware if there is a clear plan for how to make a profit from it. It gives a reasonable payload so that a moon mission would be achievable with a couple of launches.
Regards,
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7:53 pm
May 18, 2010
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KellyJ
| | Australia | |
| Member | posts 15 | |
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Post edited 7:54 pm – May 18, 2010 by KellyJ
Brandon,
Forgot to mention there are some pictures on the Wiki (http://cstart.org/wiki/Proposed_projects). A good overview of the DH-1 with basic details can be found on the Wikipedia at http://en.wikipedia.org/wiki/DH-1.
Regards
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8:10 pm
May 18, 2010
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antinode
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Post edited 8:10 pm – May 18, 2010 by antinode
I'm pretty sure you're replying to a spam bot, but you raise some good points. I think the current plan is to use a Falcon 9 for the actual rocket. I'm not entirely sure why this was decided though, or if that decision is final. It's definitely something I'd like to see considered.
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8:33 pm
May 18, 2010
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Luke Maurits
| | Adelaide, Australia | |
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I agree with the spam bot assessment, given the hockey sticks link in his comment.
I wasn't aware of the DH-1 stuff on the Proposed Projects page. It's good to see people outside the core making use of this page! I do wonder if we shouldn't give it a separate page (linked to from the Proposed Projects page) to avoid cluttering the PP page with images? Not a big deal, anyway.
I don't mean to rain on any parades, but if the quote "Practical payload of 2300kg" on the PP page is accurate, then I think the DH-1 is pretty useless for CLLARE. As mentioned, the current plan is to go with the Falcon 9 (@antinode: the main motivators for this decision are the fact that the F9 is man rated (very rare among commercial launch vehicles) and also quite cheap (in terms of $/kg)). The F9 has a maximum payload of 10450 kg, and it's quite a challenge to fit what we need for CLLARE into that! The TLI, LOI and TEI burns require a lot of propellant, many tonnes. Using a launch vehicle with a 2300 kg payload would necessitate something like 5 launches or possibly more to put all the infrastructure we need into orbit. Unless each launch cost less than around $12 million a single F9 launch would be cheaper. Even if multiple DH-1 launches were cheaper, there would need to be a lot more staging going on that necessary/desirable: even if we dedicated all 2300 kg of one launch to tanks, propellant and engines, we'd get a rocket stage which was too small for TLI, meaning we'd need to split our TLI burn over 2 or 3 stages!. Using cryogenic propellants would be even more of a challenge since they would need to keep on orbit for the time it would take to do 5 launches, which would probably be measured in months – storing LH2 in space for a week or two is hard enough. There's also the added complexity of docking all of this stuff in orbit, which would mostly have to be automated since the very many rocket stages required wouldn't be manned. Finally, unless we choose a higher than typical parking orbit, we might need extra propulsion infrastructure to maintain the orbit over the months of launches.
That's not to say this is a useless project! I don't mean to be overly negative, these are just some immediate problems I can see with using it for CLLARE. It could be entirely usable for a whole load of LEO operations which could provide a good source of income for us. That said, I would need to read the book and learn more details before really throwing too much support behind it. Good to see people proposing ideas, though!
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Main CLLARE workgroups: Mission Planning, Navigation and Guidance. I do maths, physics, C, Python and Java.
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8:37 pm
May 18, 2010
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Rocket-To-The-Moon
| | Altus, Oklahoma, USA | |
| Member | posts 685 | |
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I really wish that I had time to read it. Things have been quite crazy for me lately with school and work.
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Main Workgroups: Propulsion & Spacecraft Engineering
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12:03 am
May 19, 2010
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KellyJ
| | Australia | |
| Member | posts 15 | |
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Luke,
I understand your points, and you are actually technically correct. The problem is that over the last few decades there have been lots of companies and groups try and get involved in space. They have all run into the same problems:
1) Getting finance to be able to build and test the hardware
2) Have a viable plan to make money off the whole venture
The big picture of the space industry today is that it is dominated by a few big players with very high costs (and profits too) because of the large amount of capital needed to develope a rocket and the low number of launches to recoup the costs. "Rocket Company" is different because it approaches the technical side of space access (in terms of propellants, stages, design etc) from the business perspective of how to actually make money from it!
One analogy used is the CD-ROM developement. If there are no programs on CD, computer manufactures wont pay the relatively high cost to install them. If they are not widely installed then companies wont put use them for their software and data. Someone has to take the leap first, ie Microsoft putting Encarta onto CD to make it desirable and start that spiral of affordability.
So I would like to see progress made in addressing the issue of how to make a sustainable organisation or company which can make a profit from its work, while more importantly kicking of that spiral of more launches leading to lower costs which makes more launches possible.
I have also been a bit philosophical in thinking about how open source space programs can actually contribute and achieve things that others cant. It seems like open source as a general way of doing things is really good at either copying existing solutions (Mercury/Apollo), or in choosing options which may seem crazy but once shown to work are actually game changers. If enough work could be done on a new approach to show that the details are practical then it can interest others and spark the entrepeneurs into action!!
The other problem that has come up in other threads has been the lack of a clear outline for CLLARE. Once a stable design is chosen then people can get involved and start generating the detail design that is needed. I would think that taking on a design like this would be a great way of stepping away from all the Apollo clones which have so far been unsuccessful in kicking off cheaper/better space access, and doing something new and interesting with a real chance of being successful.
Incidentally both stages on the DH-1 are manned, as having a trained pilot is actually much easier as well as more reliable than trying to make it automatic! But you are right in that it requires a different approach to assembling moon hardware.
Regards,
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9:36 am
May 19, 2010
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Luke Maurits
| | Adelaide, Australia | |
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You make a very good point with the business thing. I won't even pretend to know anything about how to run something like CSTART in a profitable manner, and to be brutally honest I'm not at all interested in learning. That's not to say I don't want CSTART to be run a way that will make it financially sustainable – I do – but it's not something I personally want to get deeply involved with. It's not where my skills or my interests lie.
With regards to the lack of a clear outline for CLLARE, I agree that no detailed work will go ahead until we have such a plan, but it feels a little like proposing adopting the DH-1 as a solution to this problem is a case of choosing a design just so we have a design. I mean, great, a lot of the paper study of the DH-1 is done, but how do we know there aren't other designs we could come up with ourselves which aren't signficantly more suitable? Also, it's really only a very partial solution: the DH-1 solves the problem of transport from the ground to LEO, but all the other design aspects of CLLARE are still wide open. In fact, with regards to current CLLARE plans, the ground to LEO problem has had a pretty clear solution all along: buy a ride on a Falcon 9 (assuming the F9 goes ahead as planned – if it doesn't this will raise a huge question mark over CLLARE).
Again, I want to emphasise that I haven't read the book introducing the DH-1 so I could be completely missing a lot of the point or details, and I won't be able to make a really strong comment on what I think of it as a suitable option for CSTART until I have. I would definitely like to read the book some time, but it may be a little while before time and money limitations allow it.
PS: The diagrams of the DH-1 on the Wiki: did you do these yourself or did you find them on the web somewhere?
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Main CLLARE workgroups: Mission Planning, Navigation and Guidance. I do maths, physics, C, Python and Java.
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7:34 pm
May 19, 2010
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KellyJ
| | Australia | |
| Member | posts 15 | |
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Luke,
Those pictures were created by me, so no issues with any copyright or attribution. Just wanted to get an idea of the size/scale of things.
I understand your concern about the business side, but at the same time the issue of buying a launch raises the question of where that money is going to eventually come from. Who would you anticipate would spend that sort of money, aside from the cost of building all the associated hardware, and what is the return for it? If its for the science, then what is the benefit of having 1 person on the lunar surface for a couple of hours and what can they really achieve there in that time frame?
I guess I am putting forward alternatives such as this, because even if the CLLARE project does succeed and put a man on the moon, then what? What options are opened up as a result of CLLARE which werent available before?
Maybe I'm just not getting the big picture of CSTART.. very interesting talking to you all though, not trying to be difficult :-)
Regards,
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1:13 am
May 20, 2010
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Luke Maurits
| | Adelaide, Australia | |
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| posts 1483 | |
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Post edited 1:27 am – May 20, 2010 by Luke Maurits
Great work on those pictures! I wasn't acually concerned about copyright or attribution, I was wondering if you had the skills to produce those sorts of images, and clearly you do! This is good to know. Normally RocketToTheMoon does all our 3D graphics work, but the more people we have who can bring concepts "to life" with images, the better. Which software did you use to do it?
With regards to this:
I guess I am putting forward alternatives such as this, because even
if the CLLARE project does succeed and put a man on the moon, then
what? What options are opened up as a result of CLLARE which werent
available before?
Maybe I'm just not getting the big picture of CSTART.. very
interesting talking to you all though, not trying to be difficult :-)
These are, frankly, fantastic questions which needed clearer answers. This in fact ties in extremely well to another thread which antinode just revived, this thread. It's rather an old thread but it looks set to maybe get new life, and your questions here would be an excellent contribution to that new life. I'm going to repost them there and make some more comments on this matter, and I encourage you to follow the discussion there!
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Main CLLARE workgroups: Mission Planning, Navigation and Guidance. I do maths, physics, C, Python and Java.
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