Date: Fri, 13 Jan 1989 01:48-EST From: space-tech-request@cs.cmu.edu To: "~/st/lists/stdigest" Subject: Space-tech Digest #20 Contents: Joe Beckenbach preliminary design goals for space plane model Joe Beckenbach Re: preliminary design goals for space plane model Marc Ringuette Re: preliminary design goals for space plane model Ray Collins Re: preliminary design goals for space plane model Marc Ringuette Re: preliminary design goals for space plane model Craig Keithley AMSATS and other thoughts Bob Summersgill Lunar polar probe Bill Higgins Lunar polar probe Randall Parker Modular Satellites ------------------------------------------------------------ Date: Tue, 10 Jan 89 23:12:59 -0800 From: Joe Beckenbach (joe@cit-vax.caltech.edu) To: space-tech@cs.cmu.edu Subject: preliminary design goals for space plane model I've been keeping in touch with a friend in Alaska, who founded ISECCo [International Space Exploration and Colonization Company] out of a fit of 'I-want-to-go'. The main project at the moment is a one-man biosphere, whose hydroponics tanks are crowding his bedroom; another, which is in the preliminary sketch stage, is an aerospace plane. To make a long story short, he and his friends in the Alaskan contingent of ISECCo would just love to make an aerospace plane, ideally the designing started now and model construction beginning in 1991. To quote Ray [my friend]: "We are primarily interested in design at the moment: coming up with a design for a plane which meets the specs which I'll upload in a moment. Then we will build a model to test the technology which will be needed for building the aero-space plane. We have a lot of (good?) ideas but we lack skills, {as I've stated before} and so we need to have a design team who knows what they are about to take our preliminary ideas and come up with a workable design." "Here is the specs we've worked up on our aero-space plane & the model. If you want to pull a design team together for us I'll mail you the drawings too... Aero-space plane design goals & criteria: [slightly reordered for presentation] 1) EVENTUAL GOALS: A. Four people or 1000# to LEO B. Net costs $250/# or less C. Horizontal take-off and land on 10,000 feet of runway 2) FINANCIAL CONSTRAINTS: A. Design budget: $100M B. Fabrication plant development costs: $25M C. Construction cost goal: $10M D. Preliminary outlay for first model and 'infrastructure': $200M 1. includes hangar, direct support 2. includes mission control construction 3) MODEL GOALS: A. Prove technology preliminary to construction of full-scale craft B. Proof of aerodynamic modelling C. SCRAMjet technology development, using model as testbed D. Materials development: light weight & temperature resistant. E. Max speed sufficient to demonstrate desired limits 1. skin temperatures and pressures [re-entry around 2750 degrees F] 2. Maximum velocity for SCRAM-jet (flame-out speed) 3. Control & handling for re-entry simulation F. Trajectory 1. Suborbital but space-entry flight 2. Projected to cover a distance of 2k-12k miles 3. Launch from southern Gulf of Alaska [little traffic] G. Attempted recovery (if possible) 1. no landing gear [weight savings] 2. ditching near Hawaii as possible recovery area 4) MODEL CONSTRAINTS: A. Air-drop launch, from private Cessna aircraft 1. Wing drop a. weight limit 500# b. length limit probably 15' { 5 m } 2. Belly drop a. weight limit 1200# b. length limit probably 10' { 3.3 m } B. Envisioned configuration 1. Main body a. Long narrow wings b. Forward canards c. Propelled by SCRAMjet and rocket d. Gives delta-v for orbital insertion 2. Booster bodies (2) a. Attached to end of main body wings b. Drop-off after attaining flame-out velocity c. Propelled by jet engine d. Gives velocity for SCRAMjet ignition e. reusability on final product, not necessary for model C. Optimal configuration 1. L:W ratio 10:1 [excluding boosters] 2. 12' { 4 m } length 3. Wing a. 8' { 2.5 m } wingspan [including boosters] b. 14.3 square feet wing area [including boosters] c. 6.8 square feet wing area [excluding boosters] 4. Launch weight: 500# a. empty: 100# b. payload: 50# c. fuel: 325# d. boosters: (2 ea @12.5#) 25# e. wing loading (on launch): 51#/square foot {You can upload this to other networks for evaluation & critisism...} --Ray::President, ISECCo. I'm not sure which of these numbers are the most flexible to deal with: the Cessna limitations are due to the best air-launch vehicle that Ray should be able to adapt or scrounge up. The funding for the model will come from God alone knows where, but let's wait until that bridge is in sight.... Joe Beckenbach Caltech CS Department joe@cit-vax.caltech.edu Vice President "in charge of warm chairs :-)", ISECCo ------------------------------ Date: Thu, 12 Jan 89 09:27:41 -0800 From: Joe Beckenbach (joe@cit-vax.caltech.edu) To: space-tech@cs.cmu.edu Subject: followup to initial mailing I've had a few responses so far requesting the following: 1) Ray's last name. It is Collins. 2) Specific details on design. I am going to get copies of his group's sketches and try to see what the core of the design idea is. It looks to be jet-assisted horizontal launch, SCRAMjet acceleration to near-orbital velocity, and rocket power to space; four people or 1000 pounds to orbit [450 kg], with horizontal landing on a 10,000 foot runway [3.05 km] 3) How to get to Ray via e-mail. His site (University of Alaska) is on Bitnet. For those of you who know where the nearest BITNET-Internet gateway is, use that in place of the one I use; for the rest of you, you can use mine. I want to collect the internet names of BITNET gateways onto the Internet, so that everyone can make the proper access. RayCollins: FSRRC%alaska.bitnet@Hamlet.caltech.edu BITNET-Internet Gateways I know about: Hamlet.caltech.edu Please don't flood him with replies on how to do it better! Put them on the mailing list-- he KNOWS that this is an initial stab at a workable design, and that he hasn't put thought into fuels, etc. His group isn't large at all, nor with as much knowledge close to hand as he wishes. That's where the space-tech mailing list comes in. 4) Contacts about ISECCo. I have contact information which I can hand out over the Internet. ISECCo is non-profit, and stands for 'International Space Exploration and Colonization Company'. It's [hopefully] easy to see that this implies a research-based organization; Ray is trying for his PhD by experiments on closed ecosystems, namely the one-person biosphere project which is his planned thesis research topic. [Aside: the hydroponics are taking over his bedroom at the moment. Poor guy. :-] I had one response from a space-tech reader from outside the US, and so far a couple from inside the borders. I hope the international response starts and keeps going, and that research which we put into ISECCo's efforts will bear fruit. I am trying to find a good aerospace designer [or even a half-decent one] to be on this list: keep your eyes peeled, folks- the more expertise, the better. If some of us have to train up to it, well, so be it. Also, talk about 'infrastructure' will eventually be needed: what good's an aerospace plane if you can't fuel it, land it, talk to it, or pay its bills? That's right, infrastructure isn't all physical [in my view]. Joe Beckenbach [de facto ISECCo Arpanet/Internet Contact] joe@cit-vax.caltech.edu [direct arpanet connection] ------------------------------ [ Joe sent mail about some sort of trouble mailing to Ray Collins. If you have trouble, send mail to joe@csvax.caltech.edu and ask him what the latest is. -- Marc ] ------------------------------ Date: Wed, 11 Jan 1989 03:45-EST From: Marc.Ringuette@DAISY.LEARNING.CS.CMU.EDU To: Ray Collins Subject: Re: preliminary design goals for space plane model My comments - - I recommend concentrating on the full-scale vehicle when sketching out the design, not on the model. They can be designed in parallel, but the entire reason for the model is to validate the concepts which will lead to the most successful launcher. But before you can do that, you need to know exactly what you want for the final launcher. - Do you think it's any easier to build a model than it is to do the real thing? If it involves a comparable amount of effort, it might be better just to build a full-scale prototype. It could have shortcuts (mainly, more chunky construction eating into the payload capability). - I didn't see any specifics on the propulsion system. Is the scramjet intended to get the plane up to the full 8 km/s? What design could it be based on, and is a scramjet necessarily best? If someone has some more detailed ideas on what kind of propulsion to use, I'd appreciate hearing about them. -- Marc ------------------------------ Date: Wed, 11 Jan 89 14:06:24 -0900 To: marc.ringuette@daisy.learning.CS.CMU.EDU From: Marc, I agree: the full scale design must be outlined before work can begin on designing the model aero-space plane. A rough sketch is all that is needed, however, since we would expect many refinements when moving on to build the aero-space plane. Building a model is vastly easier than building a full scale aero-space plane. Materials are expected to be a large portion of our expenses and just in material I would expect the initial prototype to require up to 100x the material required for the model (this assumes all labor is provided through the dedicated members of ISECCo). Another factor is that I hope to design the model in such a fashion that it will be simple to change the configuration with (comparative) ease so that it will be possible to evaluate a number of different designs--both for engines and for aero-dynamics using the same basic ship. I think it may prove possible to turn out as many as 4/6 months (1.5 months per model) for test launching. This capability would greatly enhance out design effort: we would be about to run through a number of varying designs in a fairly short period. With a full scale device this is not feasible: I expect we will be stuck with whatever path we choose once we start construction of the aero-space plane due to financial constraints. Other factors included in the decision to build a model for a test-bed include fuel costs (each model shouldn't require much more than $1,000 for fuel, vs more than $75,000 for the aero-space plane); launch costs (model launch costs will probably be around $500 vs several thousand for the aero-space plane) and telemetry (no exact figures on this, but with the aero-space plane reliable communications may require extensive use of satalite and ground installations--none of which is cheap. The model can, if neccessary, be tracked entirely from small ground stations.) All in all, I think a series of models to test out design ideas is the way to go! Ideally I would like maybe 6 or so different aero-dynamic configurations and the same number of different propulsion configurations. We have not worked out any of the propulsion specs; those stated in the release the other day were how I though the final design would be configured: all is open to modification at this stage. New technology may provide more advanced engines but at this stage our choice for best fuel economy are limited to jet (for speeds up to 2,000 mph); SCRAM-jet (for speeds up to 5,500 mph) and rocket for the final push into space. I am hoping that a SCRAM-jet can be designed which would be able to function as a rocket--but at this point it is not available so we should not count on it... Ray Collins::President, ISECCo P.O. Box 60885 Fairbanks, AK 99706 (FSRRC@ALASKA {bitnet address}) ------------------------------ Date: Thu, 12 Jan 1989 19:25-EST From: Marc.Ringuette@DAISY.LEARNING.CS.CMU.EDU To: space-tech@cs.cmu.edu Subject: Re: preliminary design goals for space plane model I still disagree that a model is that much easier than the whole thing. The materials costs of a model will be smaller, but I think the bulk of any effort to design a vehicle or propulsion system goes into (a) designing it, and (b) preparing to manufacture it, deciding what specific parts to use, etc. For instance, the design of a small-scale scramjet is sure to be much different from the full-scale one in terms of the operating temperatures, materials, and operating speeds. The last stage, buying the parts or raw materials and building the plane, pales in comparison with the total redesign necessary between the model and the real thing. As a substitute for using a model to test the design, I think other intermediate stages are advisable, for instance (1) a pair of wings to test a full-scale scramjet at speed (2) a rocket-propelled body to test the aerodynamics and heat shielding ==== What should we do *now*? I suggest that a more detailed design of the full-scale aerospace plane is advisable before deciding how to test the individual components. To that end, I hope someone can take a crack at answering the following questions which I have at this early stage: - What are the characteristics of an appropriate scramjet? What is burned, at what temperature, and who has done the development? What kind of materials are used? - How does a scramjet compare to conventional rockets for this application? Particularly, how about engine complexity, fuel tank size, re-usability? - What kind of skin will the craft need, and what kind of similar craft have been built in testing supersonic flight? Marc Ringuette ------------------------------ Date: Thu, 12 Jan 89 01:59:29 PST From: C43CJK%ENG1.gm@hac2arpa.hac.com To: TECHREQ@hac2arpa.hac.com Subject: AMSATS and other thoughts Marc, Recently I asked about AMSATS and you suggested I contact Phil Karn. Here are the questions I presented to him and his responses: o What specifications are AMSATs designed to? NASA? MIL-STD? Where can I get a copy of the specifications? The best term to use is "ad-hoc". We use whatever we can get our hands on, without adherence to formal standards. This is not to say that the satellites are designed unprofessionally, however; many of the people involved have considerable experience in the field and they know what will and won't work. Resourcefulness is highly praised; we have been known to fly ordinary carpenter's tape measure from the local hardware store as foldable antenna elements. o What are the maximum physical limits in size and weight? Depends entirely on the launch opportunity. The heaviest amateur satellite launched to date was Oscar-13, which rode on the first Ariane 4 launch last summer. Mass was approximately 150 kg fueled. Size was very roughly one meter in diameter, but only 30-40cm high (these figures are from memory, I have the complete prints at home). o Can I get a copy of the design document for an existing AMSAT? Is this information publicly available? For Oscar-13, there is a complete set of prints (in German). I obtained these from Germany last summer when I attended a command station seminar. I do not know the policy on giving out copies; some of the technology in it has been licensed to commercial entities. o How is funding acquired. (National Science Foundation?) I wish! Funding comes from a variety of sources. Direct donations from radio amateurs, sales of auxiliary software (tracking programs, etc), some funding from the German government (their equivalent of the NSF), but, sadly, not a nickel from the US government. o What guidelines are defined for "microsats". Where can I get more information? Microsats are small (approx 8") cubes. They are packet radio store-and-forward mailboxes designed for low earth orbits. The best source of info is the set of articles in the most recent Proceedings of the ARRL Computer Networking Conference. You can get a copy from the ARRL, 225 Main St, Newington CT 06111 (203)-666-1541. ---------------------------------------------------------------------------- I am sending this simply as raw information for you to do with as you please. Generally speaking, AMSATs are not built to any specifications, with any government sponsorship, and we might find it difficult to examine existing plans for design ideas. Some questions for this conference: o Should the satellites considered be designed to any existing standards? (Waiving a few areas that increase cost by orders of magnitude!) o Does anyone have experience is getting NSF/NASA/DARPA grants? o Is it worthwhile to examine AMSAT designs for ideas? o Does anyone have specifications for existing nitrogen thrusters, space qualified batteries, solar panels, etc. Are there actually any kind of catalogs? ====== Craig Keithley ------------------------------ Date: Thu, 12 Jan 1989 15:00 EST From: Bob Summersgill Subject: Re: Lunar polar probe To: Marc- The Lunar Polar Probe is a project without a home. Or rather it has many homes, with no strong (rich) backers. NSS has a $2,000 account to be used towa rds such a project. This money was raised at a Space Development Conference for the eventual use on LPP. The money has been sitting awaiting direction. The former head of NSS, thought that the only practical way of getting the LPP was to lobby NASA/Congress. This was never done. NASA on the other hand has been talking about LPP in terms of constant numbers of years in the future. (ie. 10 years ago they said two years, 5 years ago they said two years, and now they say two years.) The Soviet Union says that they will be making a LPP, but I'm not holding my breath. The Japanesse have also expressed interest in LPP; however, the Japanesse express interest in almost everything, but do to the strict hierachical structure, many avenues are never explored. I suspect that LPP is among them. The AMSAT people want to build satellites, but are strictly concerned with the challenge of building and not of the practical use of such a probe. (What I'm attempting to say, is that it could be any satellite. There is nothing special about LPP to hold the interest of AMSAT.) SSI is interested, but has not had the success in drawing together the millions of dollars needed to pull this thing off. To their credit, they are bringing together the people working in this area for a two day (invitation only) work group to outline the necessary steps to proceed. That workshop will be held on May 8th and 9th. Gay Canough of ExtraTerrestrial Materials, Inc. will be the chair of the session presenting their findings at the SSI Princeton Conference, May 10-13. The current estimates on cost are from 2 million to 200 million depending on who does the work. There remains the problem of what to do about launch to LEO, LEO to LPO, design, funding, and production of the actual craft. I am led to believe that the Chapters meeting of NSS (at SDC in Chicago?) will be pushing the adoption of LPP as a project. (I suspect that the whole project is beyond their organizational ability. A sub-group perhaps could manage. I believe that the lunar Planetary Institute (or something like that) in Houston is also planning a roundtable to discuss the idea. As to technical info. I'm waiting for the outcome of SSI workshop. It should prove to be one of the most useful (instructive?) events in the near future. Sorry if I haven't been more helpful. Good luck. -rjs ------------------------------ Date: Thu, 12 Jan 89 11:49 CST From: Bill Higgins-- Beam Jockey Subject: Keithley's questions: Nobody knows... To: Marc.Ringuette@DAISY.LEARNING.CS.CMU.EDU Marc: The Lunar Polar Orbiter effort is still in somewhat embryonic stage. Hence none of the questions Craig Keithley asked have answers right now. This is the sort of thing that will be hashed out during the March workshop in Houston; if you'd like to get involved, head down there. The person spearheading an effort to put all the interested folks in touch is a pal of mine, Dr. Gay Canough of IBM. Gay got tired of hearing people sigh about a lunar orbiter year after year, and decided that somebody ought to organize. If you have questions, or want to get added to her mailing list, she can be reached at: ETM, Inc. (her little consulting firm) P.O. Box 67 Endicott, NY 13760-0067 (607)785-6499 evenings CANOUGH@FNALC.BITNET CANOUGH@IRISHVX2.BITNET SPAN/Hepnet: 43011::CANOUGH Below is a copy of the form Steve Abrams posted to Space Digest giving details of the Houston workshop. There will be a second, more intensive and smaller workshop in Princeton in early May, just before the Space Manufacturing Conference. ------------------------------ [ I omit the registration form for the Lunar Polar Probe Conference, relayed from a sci.space posting by Steve Abrams. Send mail to space-tech-request@cs.cmu.edu if you want it. -- Marc ] ------------------------------ Date: Thu, 12 Jan 89 18:02:21 PST From: Randall Parker To: SPACE_TECH@hac2arpa.hac.com Subject: Modular Satellites(a great idea!) We have been following the discussions of amateur satellites with considerable interest. Being "modular" kinds of software engineering guys we have a suggestion for a philosophical approach to these ambitious undertakings. Essentially, all of these proposals for satellites have a core of common requirements. A basic frame and series of subsystems could be designed for use in a number of disparate satellite projects. Then, additional subsystems can be constructed for specific projects such as the Lunar/Polar missions, a mini deep space telescope, or a materials science research platform. RGP has a strong personal interest in a satellite-borne telescope to search for asteroids with a combination of mass, composition and orbit which would be suitable for diversion to Earth's orbit. However, the core subsystems we propose would be of interest to all amateur satellite designers. This core would eliminate the duplication of common engineering requirements which cut across many of the projects which have been discussed in the space and space-tech conferences. Our approach has a number of advantages least not of which is that it satisfies the age old adage that it is necessary to crawl before an attempt to walk. The construction of the core subsystems and their use in a small mission to LEO would allow them to be tested and refined before the much larger amount of resources required for something like the Lunar/Polar mission are put at risk in a much more expensive trip to the moon. The set of core subsystems is small enough that the time to completion and the number of technological risks is sufficiently reduced to prevent the disillusionment that would occur if the project had too long a duration before its first successful trial. Volunteer efforts are very fragile and nurturing them requires visible achievements at timely intervals. We are admittedly software engineers who consider ourselves naive in the world of space hardware. But for the sake of discussion we'd like to propose a partial list of modules and their component subsystems which would be common to a variety of satellite projects. Core Module Main Mission Computer subsystem R/F transmitter/receiver Minimal power supply for free-flying core module Power Module batteries solar panels Attitude Module Gyros thrusters star/sun finder There would be Auxiliary modules which are of standard design but whose use would be mission-dependent. For instance, if you needed more power for your mission there would be standard auxiliary power modules that can be added to the basic frame. Mission specific modules would be designed specifically for a particular mission. We call these Experiment modules. Their subsystems would be designed by the people who wanted to do a specific mission(e.g. Lunar/Polar probe). What Needs To Be Done ===================== We need a more developed concept of how to divide up the Modules and subsytems. Interfaces must be defined and a basic frame and dimensions for the components must be specified. What do you all think? Randall Parker c43rgp%eng4.gm@hac2arpa.hac.com Craig Keithley c43cjk%eng1.gm@hac2arpa.hac.com GM DSO-SBO Goleta Ca These ideas which have been hatched out of our fertile and vivid imaginations should not in any way be construed to represent the opinions or policies or plans of General Motors or Delco Electronics or other subsidiaries of General Motors. ------------------------------ End of Space-tech Digest #20 *******************