Date: Sun, 31 Jan 93 05:42:28 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #103 To: Space Digest Readers Precedence: bulk Space Digest Sun, 31 Jan 93 Volume 16 : Issue 103 Today's Topics: Certification (Was: Commercial off the shelf hardware) Challenger transcript (2 msgs) Clinton's Promises (space) in Charlotte Observer (3 msgs) lunar rotation (was Earth's rotation) Reasons for SSF: sound familiar? Riding Comets (2 msgs) Solar Sail/Parachute/Brake+ The last three minutes (was Today in 1986-Remember the Challenger) Today in 1986-Remember the Challenger (3 msgs) Wishful thinking: was Using off-theshelf-components (2 msgs) Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 29 Jan 93 20:57:24 From: Wales.Larrison@ofa123.fidonet.org Subject: Certification (Was: Commercial off the shelf hardware) Newsgroups: sci.space sysmgr@king.eng.umd.edu writes... >Let me ask you two quickies: > A) Do you have to recertify every time you fly? I guess you do > because no one experiment flies that frequently (yet). > B) Is there a database of commercial hardware which has been > "flight tested"? If, let's say me and DeLuca want to put > together our own flight experiment, we can just go to a book, > pick out the pieces, integrate them, and get them tested with > a better chance of passing pre-flight checks? Dennis Wingo answers: >Answer to A) >If you do absolutely nothing to the experiment (possible in our >case) then you do not have to recertify. In 99% of instances you >modify the experiment or replace your materials or such and so >forth. You have to basically pass three major tests to get your >hardware on the shuttle in the inhabited area. > 1. Shake Test >2. Offgassing/outgassing >3. EMI/RFI > [Description deleted to save bandwidth] >B) No there isn't and it would be a good thing to have. A >qualification here is that none of this hardware flys as is. There >is ALWAYS some modifications that have to be done to meet the above >specs. ... Thought I'd toss in my $.02 worth on this too. I've recently gone through the process of certifying some major pieces of space hardware for flight on the shuttle (and also looked at certifying some other stuff for flight on other launch vehicles). To answer A), the obvious (and usually overlooked answer) is to to a life test during the cert test process. Look at the shuttle -- all of its subsystems and components are certified, and you don't recertify the vehicle each time it flies. Dennis' description is pretty much correct -- and there are a couple of acceptable shortcuts -- certification by analysis or similarity. Obviously, this works the best for systems which are pretty similar to something previously flown. For example, you have an experiment, but to get longer lifetime you add more batteries. You don't have to do Dennis' 1), 2) and 3), since you can certify by analysis and similarity. Just show that you've added more of the same batteries, secured in the same way (or an acceptable way that's passed those tests in the past). Now if you changed battery types (say from a mercury battery to a lithium battery), you'd probably have to do some tests -- but if you were smart, you could restrict those tests to just the battery, and not the whole subsystem (unless it was also massively redesigned to accommodate the battery). You'll still be asked to file a piece of paper saying the the old cert is still good and why... To get through B) simply -- no there are not general catalogs of space-rated parts -- but there are odles and odles of components, subsystems, assemblies and other stuff which has been flown before and which have been tested and certified. Doing a little research (and I can recommend a bunch of sources), you can buy a lot of "space tested" stuff. Some companies have handbooks of design techniques which have been certified for space-rated (or even manned flight space-rated) usage -- including design specs, design limits, and qualified parts and vendors. Mostly these are highly proprietary (they are a real asset in bidding on contracts), but particularly vendor component and system specs are publically available. (e.g., you'll find a part that is space-rated to "XX hrs" in "YY application" or similar, with a listing of prior uses.) And the vendor had better be able to provide documentation of these claims -- I know of several companies which have been "blacklisted" (and in some cases prosecuted/sued/put out of business) for selling parts which didn't meet strict space- rated specs. But you'll still have to cert the whole system, if you have a radical enough design from previous. Remember, even if you build a house with the best possible lumber and nails and pipes and paint -- it can still be unsafe to live in if you've not put it together in an effective manner. With a bit of luck (and smart designing) you can reduce the cert tests to just a couple of key components or subsystems, and not have to cert test the whole thing. ---------------------------------------------------------------- Wales Larrison Space Technology Investor --- Maximus 2.01wb ------------------------------ Date: Sun, 31 Jan 1993 02:11:58 GMT From: Vilkata TDK Subject: Challenger transcript Newsgroups: sci.space In <728437280.AA00100@eilc.fidonet.org> Tim.Tyler@f48.n374.z1.fidonet.org (Tim Tyler) writes: >29 Jan 93 22:58, Tesuji wrote to All: > T> A secret NASA tape reveals that the crew of the shuttle Challenger > T> not only survived the explosion that ripped the vessel apart; they > T> screamed, cried, cursed and prayed for three hellish minutes before > T> they slammed into the Atlantic and perished on January 28, 1986. > T> The tape is said to begin with a startled crewman screaming,"What > T> happened? What happened? Oh God - No!" Screams and curses are heard- > T> several crewmen begin to weep- and then others bid their families > T> farewell. > T> Two minutes forty-five seconds later the tape ends. That's when the > T> shuttles crew compartment, which remained intact after the vessel > T> exploded over the Atlantic, hit the ocean at over 2,000 miles per > T> hour, instantly killing the crew. >Well, that and the rest of that post was certainly the most tasteless thing I've seen here in ages... Why do you think it's tasteless? It happens to be the truth. I went to Space Camp for two years, and lots of those people have information the general public usually doesn't. In fact, the first year, my group's counselor was the daughter of astronaut Robert L. Stewart, Jenny (very nice). I don't remember if it was she or someone else, but someone told us that the last thing they heard _before the explosion_ was something to the effect of "Uh oh." The truth is, they were all conscious (sp?) and aware of what was happening. Which makes it that much more terrible, but that's Life, and a lot of us like to know the whole truth. -- | V I L K A T A T . D . K . ------dsblack@iastate.edu------ | |"A computer terminal is not some clunky old television with a typewriter in | | front of it. It is an interface where the mind and body can connect with | | the universe and move bits of it about."--Douglas Adams, _Mostly_Harmless_ | ------------------------------ Date: 31 Jan 93 04:20:53 GMT From: "David M. Palmer" Subject: Challenger transcript Newsgroups: sci.space Other fiction on the subject of the Challenger-- Dan Simmons Two Minutes, Forty-Five Seconds (working title: 'Love Song to J. Morton Thiokol', but Omni's lawyers suggested a change.) Included in Simmon's 'Prayers to Broken Stones'. -- David M. Palmer palmer@alumni.caltech.edu palmer@tgrs.gsfc.nasa.gov ------------------------------ Date: 30 Jan 93 11:17:10 GMT From: Pat Subject: Clinton's Promises (space) in Charlotte Observer Newsgroups: sci.space In article <1993Jan22.154806.1925@sol.ctr.columbia.edu> mjensen@herman.gem.valpo.edu (Michael Jensen) writes: | |I must agree with Dennis from Hunstville. As a extreemly low paid engineer, |I too find it sad when people continue to slam NASA for things that are out |of it's control. We who work for NASA are accepting lower salaries, and |hard work not because we want to "rip off the taxpayer" or anything close, but |because we love what we do, and we love our country. The only reason that |we have the significant majority of the problems we do encounter is because |the US Congress refuses to allow us to do our jobs the way they should be done. | I think that this is a gross over-simplification of the problems at NASA. Granted the congress screws with them, but they do so with lots of agencies. and you guys think you are underpaid, look at the forest service. Forest rangers get GS-5 salary, have to live in condemned housing and many of them have to control crime involving gangs and narcotics growers or dealers in their camps. Now that is doing the job because you love it. Also, the congress for the past 3 administrations has been pretty solid in funding NASA. the problems in SSF have come because they sold the program as costing 8 billion dollars. where are we? 40 billion and still climbing? not counting launch? Sure congress cut funds for the STS developement. but it was Jim Fletcher, a NASA employee, who decided to award Rockwell the STS orbiter, Thiokol the boosters and Rocketdyne? the SSMEs? I seem to recall McDac and Aerojet having some pretty harsh things to say about it, and claiming their proposals were technically far more sophisticated. as i recall aerojet submitted a design for jointless SRBs. It was also NASA management that decided that 51-L needed to launch in freezing weather. I don't recall tip o'neil threatening their budget on that one. The problems in galileo stem from changing criteria on the Shuttle. First it had to go on shuttle, then shuttle wouldn't carry the centaur. That was NASA changing it's flight safety rules. and their manifesting rules. HST was fouled up, because nobody had the backbone to stand up to P-E and the Air Force. not because congress didn't allocate enough money for the platform. hell, over 5 billion was spent buiilding it. how much more do you want? I for one am getting very sick of this "Blame COngress" mentality expressed by certain right wing members of this group. Look, it's inefficient and yes it changes it's mind, and yes they control the money, but that is the nature of our government. It's written into our constitution, and anyone who wants to throw a vital series of checks and balances out is un-american in my book. You guys want better salaries, push for them. but then accept other risks as well. Cetainly NASA could pay people better, but private industry lays people off right and left. Private industry works offten time on weekly financial cycles. I don't see so many happy people working at NASA contractors. And you want eerie-ness work in defense contracting. in short: life is unfair, deal. ------------------------------ Date: Sun, 31 Jan 1993 02:36:13 GMT From: Jeff Bytof Subject: Clinton's Promises (space) in Charlotte Observer Newsgroups: sci.space In article szabo@techbook.com (Nick Szabo) writes: >From: szabo@techbook.com (Nick Szabo) >Why not $10 billion for automated missions to comets, asteroids, Mars, >etc.? Why not $10 billion to help establish the phone cell sat and >DBS industries? Why not $10 billion to develop microreactors that >can make useful products out of the materials native to space? >Why not $10 billion for experiments in microgravity science, without >dictating the kind of space platform on which the experiments must >be performed? $10 billion for SSTO? For a two-stage rocket? >Why not $10 billion for nuclear-thermal and nuclear-electric upper >stages? Clinton has revealed himself in the last week and a half as a consumately political animal who tries to keep fairly easy political promises. Question: did he tour NASA facilities during the campaign and make promises that we have on videotape??? That is the key to predicting the future of NASA. -Jeff Bytof >-- >Nick Szabo szabo@techboook.com ------------------------------ Date: Sat, 30 Jan 1993 23:27:21 GMT From: Nick Szabo Subject: Clinton's Promises (space) in Charlotte Observer Newsgroups: sci.space >[govnt prize money for building station, moon base, etc.] sysmgr@king.eng.umd.edu (Doug Mohney) writes: >I got some questions for you: >(Good questions A-D deleted) But the most fundamental question is, why should the $10 billion be spent for a space station? For a lunar base? Why not $10 billion for automated missions to comets, asteroids, Mars, etc.? Why not $10 billion to help establish the phone cell sat and DBS industries? Why not $10 billion to develop microreactors that can make useful products out of the materials native to space? Why not $10 billion for experiments in microgravity science, without dictating the kind of space platform on which the experiments must be performed? $10 billion for SSTO? For a two-stage rocket? Why not $10 billion for nuclear-thermal and nuclear-electric upper stages? Playing tricks with how the government hands out the money won't do much to increase efficiency; the government contractors are just as bureaucratic as the government agencies. Most importantly, this gimmick doesn't solve the fundamental problem, which is the massive misallocation of funds. That can only be solved by some combination of (a) a radical change in strategy and vision, away the obsolete failed strategies for space development that so far have been pursued, and (b) taking the fundamental strategic decisions about where to spend the money out of the hands of the government, and putting it into the hands of those who put their own money at risk to develop real self-sustaining businesses, not in the pursuit of future government contracts. -- Nick Szabo szabo@techboook.com ------------------------------ Date: 31 Jan 93 00:29:07 GMT From: news@organpipe.uug.arizona.edu Subject: lunar rotation (was Earth's rotation) Newsgroups: sci.space mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes >-Isn't there geological evidence that shows that Earth and Moon formed >-(were not molten, which I would expect accretion of a body the size of >-the moon to result in -- gravitational energy) at the same time? >-Theat seems to me to be a death blow to any such theories of >-catastrophic formation of the moon (if what I'm remembering is >-correct). and roberts@cmr.ncsl.nist.gov (John Roberts) responds >Not sure what you're saying, but geologic evidence such as dating of igneous >rocks by content of radioactive materials doesn't generally extend further >back in time than the most recent time the rocks solidified. Much of the >rock on the moon is in the range of three to over four billion years old. >Rock at least that old has been found on Earth. These numbers only assign a >minimum to the actual ages of the Earth and moon. Actually, to reset an isotopic clock, you need to differentiate the two elements involved. For instance, partially melting mantle material in the absence of plagioclase resets the Sm-Nd system but does not effect the Rb-Sr system for the whole rock model ages. This is observed in the SNC meteorites:Rb-Sr (& U-Pb) age ~4.5Ga, Sm-Nd whole rock age ~1.3Ga, individual mineral age (Sm-Nd, U-Pb) ~200Ma. So make the planet (4.5Ga), partially melt mantle material and draw off the melt (1.3Ga), recrystallize the individual minerals (200Ma). This type of analysis is what gives us model ages for the earth and moon of about 4.5Ga. The ages are not distinguishable. Since the object-accreting-in-earth-orbit timescale is certainly less than the object-accreting-in-solar-orbit timescale, and since the later is comparable to the uncertainty in the age of earth and moon (~100Ma), I see no chronology problem for the giant impact scenario of lunar origin. Incidently, the oldest known earth rock has a crystallization age of 3.96Ga (S.A. Bowring, Geology, 1990 or 91). Oldest mineral crystallization age is 4.2Ga (sorry, no ref.) Of course, ~70% (by area) of the earth's surface rocks are <200Ma, whereas the youngest known lunar rocks are ~3Ga. I max ages I've found for lunar rocks are 4.17-4.54Ga for some of the Apollo 15, 16, and 17 samples (Geo. Terr. Planets, NASA SP-469). James N. Head jnhead@lpl.arizona.edu ------------------------------ Date: Sat, 30 Jan 1993 23:44:09 GMT From: Nick Szabo Subject: Reasons for SSF: sound familiar? Newsgroups: sci.space >In article <1993Jan27.030217.14900@iti.org>, aws@iti.org (Allen W. Sherzer) writes: >> Actually, if you look at the information that has been put out about >> SSF in the last decade you will see that the PRIMARY mission of SSF is... >> >> A. Life science (at least to the life science community). >> B. Microgravity (at least to the microgravity people) >> C. Assembly point for Moon/Mars (At least to the manned space crowd) >> D. A mechanism to teach us how to live and work in space (at least to >> the space colonization crwod) >> E. Well paying jobs for your district (at least to Congress). >> F. (insert your favoriet special interest here) >> higgins@fnalf.fnal.gov (Bill Higgins-- Beam Jockey) writes: >F1. A platform for astronomical studies from low Earth orbit. >F2. Earth observation. >F3. Space physics. My, these sound familiar. Substitute "geology" for "earth observation" and what do we get? Why, the justifications for the Next Logical Pork, The Lunar Base! (NLP-TLB, for TLA weenies :-) -- Nick Szabo szabo@techboook.com ------------------------------ Date: 31 Jan 93 03:28:41 GMT From: Josh Hopkins Subject: Riding Comets Newsgroups: sci.space aa429@freenet.carleton.ca (Terry Ford) writes: >What is the possibility of creating a craft that could land on either a near >earth asteroid, or a comet, and hitch a ride? From what I have heard, comets >and the likes travel at impressive speeds, which would be a great way to conserve energy on a deep space mission. Landing on a comet that is passing through the solar >sytem, on its way into deep space would be a great way to get out, without >having to use all the energy for propulsion. >..getting to the comet/asteroid is another problem.. Indeed. It is the critical problem. Landing on a comet to take advantage of its velocity is a little like jumping in front of a car to get a ride on the highway. You either need to have a very big cushion or you need to be going as fast as it is. The first is reasonably (though not completely) impractical. The second (matching speeds with it) brings up the question of why you would want to land on a comet if you were already going fast enough to do so. One can certainly get valuable materials from comets or asteroids and you might be able to steer them very gently through their own outgassing. Just hopping on does not appear to be practical however. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu Q: How do you tell a novice from an expert. A: A novice hesitates before doing something stupid. ------------------------------ Date: 31 Jan 93 00:03:49 GMT From: Greg Moore Subject: Riding Comets Newsgroups: sci.space In article aa429@freenet.carleton.ca (Terry Ford) writes: > > >What is the possibility of creating a craft that could land on either a near >earth asteroid, or a comet, and hitch a ride? From what I have heard, comets >and the likes travel at impressive speeds, which would be a great way to conserve energy on a deep space mission. Landing on a comet that is passing through the solar >sytem, on its way into deep space would be a great way to get out, without >having to use all the energy for propulsion. Another idea would be >to place a spacecraft on Halleys comet, or somethign else that flies by >the earth frequently. That way, on its voyage out, it could take many many >observations, without warrying about propulsion, OR sending data back to earth. >Once the comet comes close to the earth, optical communications could take >place, and all data collected could be transmitted to earth, AND any power >the probe/spacecraft had lost could be transmitted to the probe. > >..getting to the comet/asteroid is another problem.. > Actually, it's no problem. You just need to accelerate up to the speed of the comet. Gee, and you know what that means? You don't get any energy boost out of the comet. However, you do get some other benefits; such as water, some carbonates and other materials. >-- >------------------------------------------------------------------------------ >Terry Ford [aa429@freenet.carleton.ca] | "Macbeth hath murdered sleep!" >Ottawa, Ontario, Canada | "Macbeth shalt sleep no more!" >------------------------------------------------------------------------------ ------------------------------ Date: 31 Jan 93 03:58:10 GMT From: nsmca@acad3.alaska.edu Subject: Solar Sail/Parachute/Brake+ Newsgroups: sci.space In article , jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes: > jonathan.deitch@p7.f411.n133.z1.FIDONET.ORG (Jonathan Deitch) writes: > >> >From: nsmca@acad3.alaska.edu > >> >A Solar Sail if I understand right when it arrives at its Steller destination >> >it becomes a Solar Parachute/Brake. Am I right? > >>Yep ... you simply turn it around and use it to capture the *outward* solar >>wind of your destination star to slow you down. > > Solar sails do NOT use the solar wind. They run on light pressure. > > -- > Josh Hopkins jbh55289@uxa.cso.uiuc.edu > > Q: How do you tell a novice from an expert. > A: A novice hesitates before doing something stupid. Of what I have heard there is two different solar sails. One uses light, the other uses Solar Winds.. Light Sails are more practical if I remember right.. Arthur C. Clarke and friends have abook on the subject, called "Project Soalr Sail". By ROC press.. == Michael Adams, nsmca@acad3.alaska.edu Im not high, just jacked ------------------------------ Date: Sat, 30 Jan 93 22:26:11 GMT From: Joe Cain Subject: The last three minutes (was Today in 1986-Remember the Challenger) Newsgroups: sci.space,sci.space.shuttle,talk.politics.space In article <1993Jan28.210837.12267@unocal.com> stgprao@st.unocal.COM (Richard Ottolini) writes: >I know people are tired of hearing this this newsgroup, >but I am still not convinced NASA told us all about >the last moments of the astronaunts. I briefly saw a posting, I think in talk.politics.space, within the last two days, which purported to be a transcription of the last three minutes of the Challenger tape. I was in a hurry when I scanned it, and the impact did not hit me until I was out the door to an appointment.I returned later to try to remember where it was but was unable to locate it. Does anyone know the number of this or of its veracity? Playing it back in my mind I recall it starting with the publically released "last" word recorded of something like "uh oh" and then lots of painful-to-hear brief comments from several members of the crew ending with a prayer. If the transcript is valid I can understand why NASA would not wish to release the tape. The posting claimed that it lasted some 3 minutes before the Challenger hit the water at 2000 mph. Joseph Cain cain@geomag.gly.fsu.edu cain@fsu.bitnet scri::cain (904) 644-4014 FAX (904) 644-4214 or -0098 ------------------------------ Date: 31 Jan 93 03:47:03 GMT From: jason sattler Subject: Today in 1986-Remember the Challenger Newsgroups: sci.space,sci.space.shuttle sbooth@lonestar.utsa.edu (Simon E. Booth) writes: > > Just a reminder- 7 years ago today- 11:38am EST.... > > So, where were you when the Challenger disaster took place? > > I was in my junior year of high school in my Spanish III class. Our Executive Director (Principal) came on the PA and told us what had happened. Being in a Catholic School, we had several moments of silence and said a Hail Mary and Our Father for the crew and their families. I'm sure it is a day that none of us will forget. If you ever go to Arlington National Cemetary, go to the Challenger Memorial. It will leave you with an eerie feeling that you cannot describe. ------------------------------------------------------------------------------ Nickie Sattler jsattle@andy,bgsu.edu CHRISTA McAUFFLE'S MEMORY AND DREAMS WILL LIVE FOREVER!!!! ------------------------------ Date: 31 Jan 93 07:35:09 GMT From: Henry Spencer Subject: Today in 1986-Remember the Challenger Newsgroups: sci.space,sci.space.shuttle In article shafer@rigel.dfrf.nasa.gov (Mary Shafer) writes: >I work on a base named after a guy who was killed in flight test and >all the streets I drive on are named after dead aircrew. It's sad, >it's regrettable, but it happens. I still accept any ride I can... Well, Mary exaggerates slightly... I don't think Rosamond Boulevard is named after dead aircrew (it's named after the town at its west end)... but only slightly, because the rest are. The NASA History book on Dryden (NASA SP-4303, "On The Frontier") is punctuated by quiet little notes like "he was killed a year later when the XYZ-5 crashed", and it's not even discussing a lot of the USAF activity. We know that Mel Apt was the first man to reach Mach 3 only because we can read the machmeter on the cockpit camera film that was dug out of the wreckage of the X-2... This is why Jerry Pournelle is so fond of saying that the DC-Y should be flown by test pilots, not astronauts. If a test pilot dies, you sigh, hold a memorial service, name a street after him at Edwards, and then figure out what happened, fix it, and carry on flying. If an astronaut dies, the entire program comes to a screeching halt for two or three years, and no sacrifice of schedules, usefulness, or customers is too great to ensure it doesn't happen again. Except that it will anyway, no matter how badly you cripple the program in the name of safety, unless you ground the thing permanently. If we are ever to have routine spaceflight -- the sort that might get you or me up there -- this absolutely requires tolerance for the occasional crash, especially during a new vehicle's early test period... that is, its first (say) 100 flights. If your response to thinking about Challenger is "never again!", you are part of the problem, not part of the solution. When you remember Challenger, remember also that the devastating effect it had on the space program was unnecessary and unwarranted. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 31 Jan 93 07:43:20 GMT From: Henry Spencer Subject: Today in 1986-Remember the Challenger Newsgroups: sci.space,sci.space.shuttle In article <1993Jan29.184145.17677@ringer.cs.utsa.edu> sbooth@lonestar.utsa.edu (Simon E. Booth) writes: >... allegedly the last words heard on the flight recorders salvaged from >plane crashes. > >There was speculation (albiet probable urban folklore) about the recorder >from the Challenger still recording after the orbiter was destroyed. This story has been around for quite a while, but as far as I know there's no real evidence to support it. The orbiters do not have armored flight recorders like airliners. They do have recorders... powered from the main orbiter power system, so the recordings stopped as the orbiter broke up. (The transcripts were released a while ago as a result of media pressure; apart from a bit of off-the-air chitchat on the way up, there was nothing much of interest.) There were battery-powered recorders aboard too, but whether they'd be in use during ascent is unclear. The important thing to understand is that such speculation, complete with claims of NASA coverups, was absolutely predictable regardless of the facts. It's like conspiracy theories of the JFK's death or the wrecked-UFO-in-a-USAF-hanger story: it's entertaining, it sells lots of cheap newspapers, and there is absolutely no way to convincingly disprove it. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 30 Jan 93 18:59:08 GMT From: Gary Coffman Subject: Wishful thinking: was Using off-theshelf-components Newsgroups: sci.space In article <1993Jan29.180016.6500@cc.ic.ac.uk> atae@crab.ph.ic (Ata Etemadi) writes: >In <27JAN199317130244@judy.uh.edu> st17a@judy.uh.edu (University Space Society) >writes: > >>You know I feel like I am the Shell Answer man for space of late. >>You can fly any commercial hardware you like on the shuttle as long as it >>meets the flamablity, outgassing, offgassing and EMI requirements. > >Unfortunately I do not have access to a multi-million pound EMC, outgassing >etc.. test facility, or a few thousand pounds per day to hire the facilities >from people like British Aerospace (ESTEC charge a mere 10,000 pounds per week). >Furthermore, ESA require that *each* component (that means every resistor, >capacitor, etc..) be serialised, and manufatured on an ESA approved production >line. I am sure this is the same at NASA, but it seems you managed to get away >with it. You might want to consult with your colleagues at the University of Surrey who fly payloads called UoSats that include consumer video cameras and multiple commercial IMOS Transputers, on Arianne without serialized components or ESA approved production lines. Or you might contact AMSAT-NA who have flown 22 satellite payloads on Arianne without benefit of serialized parts or production lines. In fact no satellite in the series has cost over $100,000 from start to finish. The Microsat series use off the shelf commercial parts including commercial 1 megabit dynamic RAM chips. You might also want to talk to High School students who have flown homebuilt payloads in Get Away Special canisters on Shuttle. Or you might want to talk live to an Astronaut or Cosmonaut who is using a commercial off the shelf handheld radio from Motorola or Yaesu on the Shuttle and MIR. Or just listen to Dennis. Safety critical systems on the *launchers* are held to strict standards, but payloads are not held to these standards. Thermal/vacuum and vibration table testing, shake and bake, is required of payloads to assure that the payload offers no risk to the launcher or other payloads, but this is a fairly inexpensive procedure available from any number of testing labs. EMC testing is required for payload systems that will be *active* before separation from the launcher, but screen rooms are commonly available and inexpensive to rent. The AMSAT Microsats are now a proven standard experiment bus complete with communications, power management, control computers, and slots for your experiment cards. Parts cost is well under $1,000 excluding the solar panels. You really have no valid excuses other than your own ignorance and inertia preventing you from building a state of the art space payload that would be acceptable for launch. Getting someone to pay for the launch cost can be a more difficult problem, but both NASA and ESA have allowed *free* hitchhiker payloads in the past and seem willing to continue do so. A French amateur satellite is to be launched on Arianne in April. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Sat, 30 Jan 1993 23:54:38 GMT From: Mary Shafer Subject: Wishful thinking: was Using off-theshelf-components Newsgroups: sci.space I don't understand why people are whining about having to certify Shuttle payloads--I can't put a thing on a test aircraft without shake-and-bake, EMI tests, etc. as applicable. The Shuttle is even more delicate. I certainly wouldn't want someone's experiment outgassing on the middeck of the Shuttle--it's not like they can open a window for some fresh air. -- Mary Shafer DoD #0362 KotFR NASA Dryden Flight Research Facility, Edwards, CA shafer@rigel.dfrf.nasa.gov Of course I don't speak for NASA "A MiG at your six is better than no MiG at all." Unknown US fighter pilot ------------------------------ End of Space Digest Volume 16 : Issue 103 ------------------------------