A kerosene-fueled X-33 as a single stage to orbit vehicle.
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From: Androcles on 26 Apr 2010 17:48 "Dan" <B2431B(a)aol.com> wrote in message news:mMnBn.277947$wr5.116556(a)newsfe22.iad... > Androcles wrote: >> "Dan" <B2431B(a)aol.com> wrote in message >> news:y8nBn.137958$sx5.51616(a)newsfe16.iad... >>> Androcles wrote: >>>> "Dan" <B2431B(a)aol.com> wrote in message >>>> news:0zmBn.45407$Db6.4032(a)newsfe05.iad... >>>>> Androcles wrote: >>>>>> "Dan" <B2431B(a)aol.com> wrote in message >>>>>> news:h7kBn.45389$Db6.11570(a)newsfe05.iad... >>>>>>> Androcles wrote: >>>>>>>> <hallerb(a)aol.com> wrote in message >>>>>>> <snip> >>>>>>>> KSC on on florida beach so debris dont fall on residents and being >>>>>>>> south it picks up rotational speed of earth to help payload >>>>>>>> >>>>>>>> ================================================= >>>>>>>> This debris fell on residents: >>>>>>>> http://en.wikipedia.org/wiki/Space_Shuttle_Columbia_disaster >>>>>>>> So did this: >>>>>>>> >>>>>>>> http://luckybogey.files.wordpress.com/2009/08/gallery-lockerbie-anniver-002.jpg >>>>>>>> >>>>>>> Neither occurred during a rocket launch and the Lockerbie case >>>>>>> wasn't even space related. >>>>>>> >>>>>>> Dan, U.S. Air Force, retired >>>>>> Oh, I see. Only debris that falls on residents during launches is of >>>>>> any >>>>>> consequence. >>>>> I didn't say anything of the kind, did I? >>>> No, and I didn't say "KSC on on florida beach so debris dont fall on >>>> residents and being south it picks up rotational speed of earth to help >>>> payload", so let's talk some more about what we didn't say. >>>> >>>>> In response to being told the NASA launches from Florida reduce risk >>>>> to residents you brought up Columbia and Lockerbie. I addressed your >>>>> point. >>>> In response to being told debris falling from the sky was neither a >>>> rocket launch (true) nor the Lockerbie case (false), I addressed your >>>> point. Perhaps the illiterate hallerb(a)aol.com wished to inform us that >>>> living near a launch site was some kind of insurance against debris >>>> falling from the sky (or not), although I didn't say anything of the >>>> kind, did I? >>>> >>>> >>> I don't know if you are deliberately being difficult or you just can't >>> seem to follow the thread. >> >> Oh, you wanted to follow a thread! >> >> Unless you are just being deliberately difficult, go back to where it >> says >> "<snip>" and you'll find I wrote >> >> Those big pencils hang on the side of the tank to lift the tank (and >> themselves); the shuttle lifts itself but can't lift its own fuel. In >> short, >> it's an expensive clusterfuck and a double failure to be scrapped. >> >> If a plane takes off into the wind the least an orbiter could do is >> take off from a mountain, taking any advantage available. Denver >> is mile-high city, why take off from sea level? >> Fuel is burnt as a function of time, not altitude or velocity, so >> an electric sled on a ramp providing the initial acceleration would >> enable a greater payload. >> >> Of course someone that wanted to follow a thread wouldn't deliberately >> <snip> and go off on a fuckin' tangent just be difficult, would he? >> >> I don't know if you are deliberately being difficult are just fuckin' >> stupid. >> <SNIP RIGHT BACK AT YA!> >> >> >> > Well, seeing as you feel airplanes dropping from the air and vulgar > abuse are proper debate on space launches I don't think we have anything > further to discuss. Have a nice day. > > Dan, U.S. Air Force, retired As I thought, just fuckin' stupid. Have a nice day. Androcles, RN Sea Harrier supplier, retired.
From: Androcles on 26 Apr 2010 23:16 "Jim Yanik" <jyanik(a)abuse.gov> wrote in message news:Xns9D66DC9B5C822jyaniklocalnetcom(a)216.168.3.44... > Dan <B2431B(a)aol.com> wrote in news:mMnBn.277947$wr5.116556(a)newsfe22.iad: > >> Androcles wrote: >>> "Dan" <B2431B(a)aol.com> wrote in message >>> news:y8nBn.137958$sx5.51616(a)newsfe16.iad... >>>> Androcles wrote: >>>>> "Dan" <B2431B(a)aol.com> wrote in message >>>>> news:0zmBn.45407$Db6.4032(a)newsfe05.iad... >>>>>> Androcles wrote: >>>>>>> "Dan" <B2431B(a)aol.com> wrote in message >>>>>>> news:h7kBn.45389$Db6.11570(a)newsfe05.iad... >>>>>>>> Androcles wrote: >>>>>>>>> <hallerb(a)aol.com> wrote in message >>>>>>>> <snip> >>>>>>>>> KSC on on florida beach so debris dont fall on residents and >>>>>>>>> being south it picks up rotational speed of earth to help >>>>>>>>> payload >>>>>>>>> >>>>>>>>> ================================================= >>>>>>>>> This debris fell on residents: >>>>>>>>> http://en.wikipedia.org/wiki/Space_Shuttle_Columbia_disaster >>>>>>>>> So did this: >>>>>>>>> >>>>>>>>> http://luckybogey.files.wordpress.com/2009/08/gallery-lockerbie- >>>>>>>>> anniver-002.jpg >>>>>>>>> >>>>>>>> Neither occurred during a rocket launch and the Lockerbie case >>>>>>>> wasn't even space related. >>>>>>>> >>>>>>>> Dan, U.S. Air Force, retired >>>>>>> Oh, I see. Only debris that falls on residents during launches is >>>>>>> of any >>>>>>> consequence. >>>>>> I didn't say anything of the kind, did I? >>>>> No, and I didn't say "KSC on on florida beach so debris dont fall >>>>> on residents and being south it picks up rotational speed of earth >>>>> to help payload", so let's talk some more about what we didn't say. >>>>> >>>>>> In response to being told the NASA launches from Florida reduce >>>>>> risk to residents you brought up Columbia and Lockerbie. I >>>>>> addressed your point. >>>>> In response to being told debris falling from the sky was neither a >>>>> rocket launch (true) nor the Lockerbie case (false), I addressed >>>>> your point. Perhaps the illiterate hallerb(a)aol.com wished to inform >>>>> us that living near a launch site was some kind of insurance >>>>> against debris falling from the sky (or not), although I didn't say >>>>> anything of the kind, did I? >>>>> >>>>> >>>> I don't know if you are deliberately being difficult or you just >>>> can't >>>> seem to follow the thread. >>> >>> Oh, you wanted to follow a thread! >>> >>> Unless you are just being deliberately difficult, go back to where it >>> says "<snip>" and you'll find I wrote >>> >>> Those big pencils hang on the side of the tank to lift the tank (and >>> themselves); the shuttle lifts itself but can't lift its own fuel. In >>> short, it's an expensive clusterfuck and a double failure to be >>> scrapped. >>> >>> If a plane takes off into the wind the least an orbiter could do is >>> take off from a mountain, taking any advantage available. Denver >>> is mile-high city, why take off from sea level? >>> Fuel is burnt as a function of time, not altitude or velocity, so >>> an electric sled on a ramp providing the initial acceleration would >>> enable a greater payload. >>> >>> Of course someone that wanted to follow a thread wouldn't >>> deliberately <snip> and go off on a fuckin' tangent just be >>> difficult, would he? >>> >>> I don't know if you are deliberately being difficult are just fuckin' >>> stupid. >>> <SNIP RIGHT BACK AT YA!> >>> >>> >>> >> Well, seeing as you feel airplanes dropping from the air and vulgar >> abuse are proper debate on space launches I don't think we have >> anything further to discuss. Have a nice day. >> >> Dan, U.S. Air Force, retired >> > > How much would be gained by a one mile change in launch point altitude? 5000 feet at 3G, let's see... 5000 = 1/2 * 3* 32 fps/sec *t, so t = 5000/(0.5 * 3 * 32) ~= 100 seconds burn. How long does an SRB burn for? Burn Time: 123.6 sec action, 111.7 sec web. http://www.astronautix.com/engines/srb.htm A ramp/sled launch would gain an SRB. > Enough to warrant putting a launch site in a rough,inaccessible area? A launch ramp up the side of a mountain could be difficult, although the Swiss seem to like skiing in rough, inaccessible areas, they put cable cars up hillsides and bore tunnels through the Alps just for the pleasure of it. The French and the British even have a 26 mile long tunnel under the English channel, I daresay some enterprising American company could build a straight railroad track for more than a couple of miles. > Doubtful. > I note that Florida can receive the barges that the SRB segments are > shipped on,ISTR the railways can't handle them. > I'm sure any real engineering is way beyond your capabilities, instead of any calculation you'll have a doubtful. There wouldn't be any SRBs with a ramp launch replacement. > then there's the weather problems of the high altitudes. > Then there's the weather problems in Florida, freezing SRBs causing the Challenger tank to blow, to say nothing of the constant lightning strikes. But I'm sure you are right. Let's all say nay, pack up and go home, nobody wanted to go above atmosphere anyway.
From: Robert Clark on 28 Apr 2010 22:56 Another question asked in email and on different forums about this is, if the Russians already had these high performance kerosene engines that make SSTO possible why aren't they doing it? I wondered about that too. I thought their new Angara rocket should be SSTO capable since it will be using these high performance kerosene engines. But then I checked the specifications of the Angara rocket on the SpaceLaunchReport.com site: Space Launch Report: New Launchers - Angara. http://www.spacelaunchreport.com/angara.html I found that the Angara mass ratios are significantly worse than for the SpaceX Falcon launchers. In fact, in general the Russian launchers are not as well mass optimized as the American launchers. This probably is a big part of the reason the Russians have had this great drive to increase the performance of their kerosene engines - out of necessity. Then to get SSTO you use the best features of both the American and Russian designs combined into one. Bob Clark On Mar 14, 9:24 pm, Robert Clark <rgregorycl...(a)yahoo.com> wrote: > The SpaceLaunchReport.com site operated by Ed Kyle provides the > specifications of some launch vehicles. Here's the page for the Falcon > 1: > > Space Launch Report: SpaceX Falcon Data Sheet.http://www.spacelaunchreport.com/falcon.html > > Quite interesting is that the total mass and dry mass values for the > Falcon 1 first stage with Merlin 1C engine give a mass ratio of about > 20 to 1. This is notable because a 20 to 1 mass ratio is the value > usually given for a kerosene-fueled vehicle to be SSTO. However, this > is for the engine having high vacuum Isp ca. 350 s. The Merlin 1C with > a vacuum Isp of 304 s probably wouldn't work. > However, there are some high performance Russian kerosene engines that > could work. Some possibilities: > > Engine Model: RD-120M.http://www.astronautix.com/engines/rd120.htm#RD-120M > > RD-0124.http://www.astronautix.com/engines/rd0124.htm > > Engine Model: RD-0234-HC.http://www.astronautix.com/engines/rd0234.htm > > However, I don't know if this third one was actually built, being a > modification of another engine that burned aerozine. > > Some other possibilities can be found on the Astronautix site: > > Lox/Kerosene.http://www.astronautix.com/props/loxosene.htm > > And on this list of Russian rocket engines: > > Russian/Ukrainian space-rocket and missile liquid-propellant engines.http://www.b14643.de/Spacerockets_1/Diverse/Russian%20engines/engines... > > The problem is the engine has to have good Isp as well as a good T/W > ratio for this SSTO application. There are some engines listed that > even have a vacuum Isp above 360 s. However, these generally are the > small engines used for example as reaction control thrusters in orbit > and usually have poor T/W ratios. > For the required delta-V I'll use the fact that a dense propellant > vehicle may only require a delta-V of 8,900 m/s, compared to a > hydrogen-fueled vehicle which may require in the range of 9,100 to > 9,200 m/s. The reason for this is explained here: > > Hydrogen delta-V.http://yarchive.net/space/rocket/fuels/hydrogen_deltav.html > > Then when you add on the fact that launching near the equator gives > you 462 m/s for free from the Earth's rotation, we can take the > required delta-V that has to be supplied by the kerosene-fueled > vehicle as 8,500 m/s. > I'll focus on the RD-0124 because of its high Isp, 359 s vacuum and > 331 s sea level. On the "Russian/Ukrainian space-rocket and missile > liquid-propellant engines" page its sea level thrust is given as > 253,200 N, 25,840 kgf. However, the Falcon 1 first stage weighs 28,553 > kg. So we'll need two of them. Each weighs 480 kg, so two would be 960 > kg. This is 300 kg more than the single Merlin 1C. So the dry mass of > the Falcon 1 first stage is raised to 1,751 kg. There is a RD-0124M > listed on the Astronautix page that only weighs 360 kg, but its sea > level Isp and thrust are not given, so we'll use the RD-0124 until > further info on the RD-0124M is available. > Taking the midpoint value of the Isp as 345 s we get a delta-V of > 345*9.8ln(1 + 27102/1751) = 9,474 m/s (!) Note also the achieved delta- > V would actually be higher than this because the trajectory averaged > Isp is closer to the vacuum value since the rocket spends most of the > time at altitude. > This calculation did not include the nose cone fairing weight of 136 > kg. However, the dry mass for the first stage probably includes the > interstage weight, which is not listed, since this remains behind with > the first stage when the second stage fires. Note then that the > interstage would be removed for the SSTO application. From looking at > the images of the Falcon 1, the size of the cylindrical interstage in > comparison to the conical nose cone fairing suggests the interstage > should weigh more. So I'll keep the dry mass as 1,751 kg. > Now considering that we only need 8,500 m/s delta-V we can add 636 kg > of payload. But this is even higher than the payload capacity of the > two stage Falcon 1! > We saw that the thrust value of the RD-0124 is not much smaller than > the gross weight of the Falcon 1 first stage. So we can get a vehicle > capable of being lifted by a single RD-0124 by reducing the propellant > somewhat, say by 25%. This reduces the dry weight now since one > RD-0124 weighs less than a Merlin 1C and the tank mass would also be > reduced 25%. Using an analogous calculation as before, the payload > capacity of this SSTO would be in the range of 500 kg. > We can perform a similar analysis on the Falcon 1e first stage that > uses the upgraded Merlin 1C+ engine. Assuming the T/W ratio of the > Merlin 1C+ is the same as that of the Merlin 1C, the mass of the two > of the RD-124's would now be only 100 kg more than the Merlin 1C+. > The dry mass and total mass numbers on the SpaceLaunchReport page for > the Falcon 1e are estimated. But accepting these values we would be > able to get a payload in the range of 1,800 kg. This is again higher > than the payload capacity of the original two stage Falcon 1e. In fact > it could place into orbit the 1-man Mercury capsule. > The launch cost of the Falcon 1, Falcon 1e is only about $8 million - > $9 million. So we could have the first stage for that amount or > perhaps less since we don't need the engines which make up the bulk of > the cost. How much could we buy the Russian engines for? This article > says the much higher thrust RD-180 cost $10 million: > > From Russia, With 1 Million Pounds of Thrust. > Why the workhorse RD-180 may be the future of US rocketry. > Issue 9.12 | Dec 2001 > "This engine cost $10 million and produces almost 1 million pounds of > thrust. You can't do that with an American-made engine."http://www.wired.com/wired/archive/9.12/rd-180.html > > This report gives the price of the also much higher thrust AJ26-60, > derived from the Russian NK-43, as $4 milliion: > > A Study of Air Launch Methods for RLVs. > Marti Sarigul-Klijn, Ph.D. and Nesrin Sarigul-Klijn, Ph.D. > AIAA 2001-4619 > "The main engine is currently proposed as the 3,260 > lb. RP-LOX Aerojet AJ26-60, which is the former > Russian NK-43 engine. Thrust to weight of 122 to > 1 compares to the Space Shuttle Main Engines > (SSME) 67 to 1 and specific impulse (Isp = 348.3 > seconds vacuum) is 50 to 60 seconds better than > the Atlas II, Delta II, or Delta III RP-LOX engines. > A total of 831 engines have been tested for > 194,000 seconds. These engines are available for > $4 million each, which is about 10% the cost of a > SSME."http://mae.ucdavis.edu/faculty/sarigul/aiaa2001-4619.pdf > > Then the much lower thrust RD-0124 could quite likely be purchased > for less than $4 million. So the single RD-0124 powered SSTO could be > purchased for less than $12 million. > > Even though the mathematics says it should be possible, and has been > for decades, it is still commonly believed that SSTO performance with > chemical propulsion is not possible even among experts in the space > industry: > > Space Tourism is a Hoax > By Fredrick Engstrom and Heinz Pfeffer > 11/16/09 09:02 AM ET > "In 1903, the Russian scientist Konstantin Tsiolkovsky established the > so-called rocket equation, which calculates the initial mass of a > rocket needed to put a certain payload into orbit, given that the > orbital speed is fixed at 28,000 kilometers per hour, and that the > maximum speed of the gas exhausted from the rocket that propels it > forward is also fixed. > "You quickly find that the structure and the tanks needed to contain > the fuel are so heavy that you will never be able to orbit a > significant payload with a single-stage rocket. Thus, it is necessary > to use several rocket stages that are dumped on the way up to get any > net mass, i.e. payload, into orbit. > "Let us look at the most successful rocket on the market the > European Ariane 5. Its start weight is 750 tons, of which 650 tons are > fuel, 80 tons are structure and around 20 tons are left for low Earth > orbit payload. > "You can have a different number of stages, and you can look for minor > improvements, but you can never get around the fact that you need big > machines that are staged to reach orbital speed. Not much has happened > in propulsion in a fundamental sense since Wernher von Brauns Saturn > rocket. And there is nothing on the horizon, if you discount > controlling gravity or some exotic technology like that. In any case, > it is not for tomorrow."http://www.spacenews.com/commentaries/091116-space-tourism-hoax.html > > The Cold Equations Of Spaceflight. > by Jeffrey F. Bell > Honolulu HI (SPX) Sep 09, 2005 > "Why isn't Mike Griffin pulling out the blueprints for X-30/NASP, DC-X/ > Delta Clipper, or X-33/VentureStar? Billions of dollars were spent on > these programs before they were cancelled. Why aren't we using all > that research to design a cheap, reusable, Single-Stage-To-Orbit > vehicle that operates just like an airplane and doesn't fall in the > ocean after one flight?" > "The answer to this question is: All of these vehicles were fantasy > projects. They violated basic laws of physics and engineering. They > were impossible with current technology, or any technology we can > afford to develop on the timescale and budgets available to NASA. They > were doomed attempts to avoid the Cold Equations of Spaceflight."http://www.spacedaily.com/news/oped-05zy.html > > Then it is important that such a SSTO vehicle be produced even if > first expendable to remove the psychological barrier that it can not > be done. Once it is seen that it can be done, and in fact how easily > and cheaply it can be done, then there it will be seen that in fact > the production of SSTO vehicles are really no more difficult than > those of multistage vehicles. > Then will be opened the floodgates to reusable SSTO vehicles, and low > cost passenger space access as commonplace as trans-oceanic air > travel. > > Bob Clark
From: Robert Clark on 1 May 2010 09:33 I'm looking for a numerical trajectory integration program if anyone has access to one. These are the conditions under which I want to estimate the required delta-V to orbit: 1.)use a dense propellant such as kerosene/LOX; dense propellants are known to reduce gravity losses. 2.)use a moderate to high liftoff thrust/weight ratio, say, 1.4 and above; high liftoff T/W also reduces gravity losses. 3.)launch near equator to get the ca. 460 m/s tangential boost. 4.)only get to 100 km, the altitude considered space, to just launch satellites or make orbital transfers, not for long term orbits. Bob Clark
From: Androcles on 1 May 2010 11:47
"Robert Clark" <rgregoryclark(a)yahoo.com> wrote in message news:224e492b-c360-49b4-88c8-b677acc7ffb7(a)s2g2000yqa.googlegroups.com... > I'm looking for a numerical trajectory integration program if anyone > has access to one. > These are the conditions under which I want to estimate the required > delta-V to orbit: > > 1.)use a dense propellant such as kerosene/LOX; dense propellants are > known to reduce gravity losses. > > 2.)use a moderate to high liftoff thrust/weight ratio, say, 1.4 and > above; high liftoff T/W also reduces gravity losses. > > 3.)launch near equator to get the ca. 460 m/s tangential boost. > > 4.)only get to 100 km, the altitude considered space, to just launch > satellites or make orbital transfers, not for long term orbits. > > > Bob Clark I'm looking for a numerical integration naval chart program if anyone has access to one. These are the conditions under which I want to estimate the required delta-X to Antarctica: 1.)use a light propellant such as coal/air heated steam; steamship propellers are known to reduce wind losses. 2.)use a moderate to low buoyancy ratio, say, 1.0 and below; low buoyancy ratios also reduce wind losses. 3.)launch near Plymouth to get the ca. 460 mile anthracite boost. 4.)only get to Australia, the place considered the southern continent, to just launch rowing boats or make ship-to-ship transfers, not for long term voyages. If anyone needs the right information to supply such a program please see Robert Clark. |