Oxygen is made in space stations by electrolysis, turning water into oxygen and hydrogen. Oxygen is used but hydrogen is vented out to space. However liquid hydrogen is best cryogenic material for cooling. In ISS space station is Alpha Magnetic Spectrometer, that was planned to use helium as coolant, but that was abonded because there was leak in AMS and it cannot be cured, so helium cooling was abonded altough that enormously weakened instrument s sensitivity. Also space telescopes like Herschel space telescope (weight 3,3 tons) and James Webb telescope (6,5 tons) could use liquid coolant, altough that was abonded in Webb also. If AMS is liquid cooled it can use station s waste hydrogen and instrument s sensitivity improves dramatically. Also liquid hydrogen can be used as coolant in astronomical telescope in space station, Webb or Herschel are so light that they don t add much to ISS total weight, they have own position control system so they can be operated separately from ISS. Also when space telescopes are build their components are often duplicated for testing etc. reasons, but that duplicate version of telescope stays in ground when telescope is launched in space. It would be cheap to use those duplicated components to send Webb or Herschel telescope duplicate to space station and use liquid hydrogen to cool it. Because those duplicate components exist in form or another, building another space telescope that is send to ISS is relatively cheap process compared to total cost of Herschel and Webb projects. This ISS duplicate telescope would also be safety measure to test telescope systems in space before “real” space telescope is launched. Webb telescope uses complex automatic petal assembly system that is never tested in space. What if something goes wrong? Sending telescope duplicate to ISS and testing its operational capability there is relatively cheap compared to Webb telescope total cost. That Webb telescope duplicate can be used in ISS many years, doubling Webb s time of observations altough near earth is not so good place than moon for observations. Or Webb telescope duplicate can be send to low earth orbit and not connected to ISS, and if it works fine real Webb launched afterwards. Cost of 6,5 ton load to low earth orbit is very small nowdays compared to Webb / JWST total budget. Why AMS was choosed to be without coolant when in ISS hydrogen is available, but it is vented to space, altough in liquid form it is excellent coolant, better than helium? If in AMS liquid coolant will evaporate, ISS constantly generates hydrogen when oxygen is produced, so ISS would be endless source of hydrogen for AMS.
When Stratolaunch ceased operations this year that meant that most economical and most technologically sophisticated project for cheap space launch was abandoned. At same time Boeing receives billions of dollars USA government money for space launch system that is already outdated before leaving drawing board, and enormously costly to operate. So mistakes of space shuttle are done again. Space shuttle was such a fiasco that similar has never before appeared in scientific projects. Best way to use shuttle would have been turning that launch system to unmanned heavy lift rocket, it would have been success, but Shuttle C and Shuttle Z were cancelled, as was cancelled “low cost cargo vehicle”. Shuttle Z could have used Ariane 5 core stage or Delta 4 core stage without engines (one shuttle engine would be used in it), maybe for free if ESA paid costs, and low cost cargo vehicle would used shuttle s big liquid fuel tank for transporting load up to 8 m wide to space. It was first proposed simply to carry fuel to space, and then if cargo space is added after bottom of fuel tank also 8 m wide cargo could been transported. So 8 m space telescopes could be launched to space and weighting about 80 tons. When shuttle ended its useful life solid boosters and rocket engines could have been used to launch massive 90 - 140 ton loads to space, and there was rocket engines left for about 16 - 17 such flights when rocket boosters and motors are discarded after every flight. And that would have been cost efficient. But it never happened, Shuttle C and Z and low cost cargo vehicle were abandoned for “cost reasons”, shuttle was so expensive to operate, that this only way to to turn shuttle to real efficient space launch system was abandoned because there was no money left to properly design those projects further. Also solid boosters proved to expensive to use, their recovery and reusing cost 2,5-3 times more than just discarting boosters after use. They could have been replaced by cheap ukrainian Zenit first stage boosters, non-reusable but cheap, and space shuttle flights would have been cheaper.
“Low cost cargo vehicle” / “Low-value cargo vehicle” (design study from late 1980s / early 1990s) was just shuttle s big fuel tank that had aft space for shuttle rocket engines and cargo space. Cargo was not in the upmost section like rockets usually have, but bottom behind fuel tank. That vehicle had shuttle s solid boosters and fuel tank but not the shuttle itself, cargo and rocket engines were behind fuel tank. Two “worn out” shuttle rocket engines would have been used. It would have been really cheap way to turn shuttle to cheap heavy launch vehicle. If instead of shuttle engines russian RD-0120 engines would been used, and instead of solid boosters ukrainian Zenit first stage (2 of them replacing solid boosters, or 4 for heavy loads), cheap heavy non-reusable launch vehicle would been true, and operating costs much cheaper than shuttle. Shuttle was launched 135 times, if for example 50 times instead of shuttle, unmanned shuttle - based cargo vehicle would been used, enormous amount of cargo could have been hauled to space. And with less cost. If shuttle s main engines would have been replaced to RD-0120s, that would make shuttle more economical still. Overhauling shuttle engines become very costly after each flight, so cheap russian rocket engines that simply were jettisoned after use would have been cost effective solution. Shuttle Z was concept for max. 135 ton cargo lifting launch vehicle. If it had used Ariane 5 core stage or Delta 4 core stage (without engines) as extra fuel tank bolted in shuttle s fuel tank side or used it as additional stage with one RD-0120 rocket engine, and cargo space behind big fuel tank, not in side of tank like shuttle, cheap launch vehicle of 135 ton capacity would have been true. None of this happened, for some reason the only effective way to use shuttle components, heavy unmanned launch vehicle, never leaved drawing board. There was chance to lift really heavy loads to space when shuttle was used, and shuttle was launched 135 times, but never was this cargo lifting capacity used, not even once.
Other wasted opportunities: Russian Energia / Vulkan rocket was relative cheap in early 1990s, one shuttle flight cost 250 million dollars and one Energia launch 285 (?) million. Vulkan rocket had second stage weighting about 750 - 705 ton (?), never build. Space shuttle fuel tank weights 760 ton so it could have been used as second stage for Vulkan, with cargo bay behind tank for 175 ton cargo and then one RD-0120 rocket motor. That configuration could have launched massive loads to outer planets, like proposed High-Z (Hi-Z) infrared space telescope by POIROT / Edison team, with 8 m mirror, send to faraway space (in orbit between Earth and Jupiter where it could observe in infrared without dust of solar system). There was at same time 1990s also proposal for about 100m - 50m or so optical space telescope build in space by manned crew, structure like RATAN 600 radio telescope, ring- like optical space telescope with very wide structure but ring- like optical surface, actual width of mirror elements was about 4,5 m (?) or so planned but in about 100m (?) wide ring of multiple elements. Low cost cargo vehicle or Shuttle Z or Energia / Vulkan could have been used to transport mirror parts to space, and Soyuz or Space Shuttle could have transported building crew. Vulkan could have been used for Mars manned mission. Vulkan could have even third stage, Ariane 5 core stage at shuttle fuel tank s side, and even more efficient rocket for outer space exploration could have been true. Zenit boosters and Energia core stage would been used. I remember that earlier “core stage” was called “1,5 stage” or simply second stage in rockets, nowdays it is called core stage.
Also astronomy research capacity of shuttle was not used. ASTRO-SPAS (3,2 - 3,6 ton) and SPARTAN (about 1 ton) shuttle pallet satellites were lightweight and fairly short (ASTRO-SPAS had 1,6 m length, SPARTAN 201 had 1,8 m length and weight 1,5 ton) so they could have been used in almost every shuttle mission, when shuttle launched satellite to space, ASTRO-SPAS or SPARTAN could have been launched too, and with extented duration (EDO) pack used in shuttle or without it, and reduced crew of 2-3 astronauts instead of 7, from three weeks to 50 days (or 100 days with double EDO) time for astronomy observation could have been possible, with each flight. Even without EDO three weeks would been possible with 2-3 man crew. Shuttle had 18,3 m long cargo bay so length was not a problem, and weight neither. But all this opportunity for groundreaking astronomy research was (mostly) not used. ASTRO-SPAS and SPARTAN flew few times, with few days duration, but could have been used in almost every mission, and much longer times. Also shuttle based telescopes like BBXRT could also been used same time when pallet satellites were used, BBXRT was very slim and mirror weight of only 40 kg, so it would fit in cargo bay in small space and had not much weight.
If cheap space shuttle boosters were needed, indian PSLV liquid first stages or GSLV solid boosters could have been used, grouped around shuttle fuel tank. GSLV boosters would be much cheaper solution than new solid boosters for that expensive “Space launch system” that USA builds now. Indian space rockets have same advantages that SeaLaunch had in the 1990s, indian rockets can launch heavy loads to space at low price, which is again opportunity to launch real heavy but low cost scientific satellites. Is this opportunity wasted again? Also China and Russia can offer low cost of heavy satellite launches, russian rockets are used to launch scientific satellites (Land Launch in south america), but chinese rockets not so often.
SeaLaunch was another wasted opportunity, science satellites could have been launched at low price and high weight, but it never had much orders and went bankrupt. Scientific satellites could have been much more bigger and heavier, at low launch costs, so their science research would been much more efficient and produced much better scientific results, but for some reason SeaLaunch never attained any interest from scientific satellite launches.
Another wasted opportunity: When intercontinental mssiles and intermediate missiles like SS 4 and SS 5 were scrapped in early 1990s, that would been massive source for space launch rockets at minimal costs. Hundreads of rockets at low cost. Failure rate could been perhaps big, those missiles used liquid propellants, but price would have been super cheap. Those missiles when phased out after nuclear arms negotiations could have been stored in some neutral country, like in Switzerland or Brazil, and used for satellite launches. But no, hundreads of very efficient rockets were just scrapped, altough they could have been used for satellite launches at scrap metal price almost. That hundreads of rockets at cheap price would offered enormous launch capacity to launch hundreads cheap loads to space. That could have been the dawn of very cheap space exploration and commercial use of outer space. But it never happened. Removing and destroying missile systems from those rockets and using them as space rockets was possible, and storing those rockets in some neutral country or countries, in “rocket storage”, but this possibility was wasted like all other opportunities for cheap space launch systems in the 1990s. I don t know for what reason.
There is in netpage “Forum nasa spaceflight com” “HLV vs. 10-40 MT launchers economics for exploration” 2009.
When space shuttle ceased operations ASTRO-SPAS and SPARTAN satellites could have been left in ISS space station, they were fairly lightweight so not much added weight to ISS. They could fly free not connected to ISS and return for charging their batteries and then fly again. Space station mechanical arm could have been used for recovering them. Those pallet satellites were not used in ISS. Also Shuttle based telescopes like HUT and others from ASTRO missions could have been assembled to ISS structure and used as part of ISS. They had low weight / size requirements, adding almost insignificant weight / size to ISS. But this never happened either. Enormous possibility for groundbreaking and valuable astronomy research at very cheap price was wasted when ISS was build.
“Steam balloon satellite launch” is new method to launch satellites to space, perhaps up to 30 ton rocket can hung under very large steam balloon. Steam was chosen because lifting gases are expensive (helium) and dangerous (hydrogen). Steam however is cheap.
And last wasted opportunity: Russian MAKS space shuttle was all that american shuttle was not, it was technologically advanced thing in early 1990s, and even for today s standards 30 years later it is, and it had all those merits that american space shuttle had not, making MAKS really cheap and effective space launch system, with launch costs of very small percentage of american shuttle s 1,5 billion dollar per launch cost. MAKS was cancelled due to breakup of Soviet Union and economical turmoil in Russia. Americans could have simply bought MAKS project from russians and continue it as international USA - Russia co-project. MAKS was almost ready when Soviet Union dissolved, so at very cheap price USA could have got really advanced space launch system that was light years ahead of american shuttle in operating concept and launching costs. If MAKS would been build it would make true all those claims of cheap cost of space launch that american shuttle promised but terribly failed. MAKS was all that Nasa and USA wanted the space shuttle to be. And it was real project nearing completion, not just another drawing board project. So cost for finished product would be very small. But it never happened. Now almost 30 years later MAKS is still perhaps best space launch system ever made. Now americans are building “Space launch system” and other horrendous waste of money for outdated technology projects that american government paid for all these years.
“Phoenix: a low cost commercial approach to the crew…” “Phoenix M: a small SSTO launch vehicle for…” Phoenix is also name of Darpa satellite program. “Ultra low cost access to space (ULCATS)”, “Citizen s space agenda”, Asgardia.
Rocket fuel tanks and habitat capsules are build around cylinderical structure, cylinderical structure that is fuel tank or capsule is the structural strength carrying structure. But what about if supporting structures are used inside rocket itself? All kind of pillars and support structures cross fuel tank and living quarters. Fuel tanks could use honeycomb support structure across fuel tank, fuel flows across this honeycomb support structure, honeycomb support structures are assembled so that fuel can flow from top of tank to bottom. Honeycomb structure can be very thick, like sieve, from fuel tank wall to another wall through fuel tank. Also not only horizontal honeycomb structure is possible, vertical honeycomb supprt can be used simultaneysly, but it needs holes in honeycomb “cells” so that fuel can flow or structure assembled so that fuel can flow through it. Different layers of thin honeycomb supporting structures can be build across fuel tank in layers from top to bottom of tank, arranged so that fuel can flow. Aeroplanes have integral tank principle, fuel is inside wing, in its supporting structure, and fuel flows through supporting structure inside wing. Integral fuel tank principle can be used in rocket fuel tanks also. Support structures goes through fuel tank, and are not outside tank in tank walls in its structural strength. “Integral rocket fuel tank” would had then whole tank as structural support structure, fuel goes through honeycomb support structure inside tank, and honeycomb structure is build in many differently positioned vertical layers from top to bottom so fuel can flow through whole tank and fuel does not stay in one narrow honeycomb “cell”. Integral rocket fuel tank is just fuel tank that has support structure going through tank, plumbing and rocket motors etc. is outside fuel tank. Solid rockets can use vertical honeycomb support through fuel tank. Also living quarters of rocket can use support structure through capsule principle, pillars assembled in shape of X or V or another form go through capsule, or other kind of strength support goes through living quarters, like “fishbone” style organic looking structure or other. Moving in capsule may be difficult if there is support pillars from wall to wall across floors and walls everywhere, but in weightless space those obstructions perhaps are not so bad, people can go around them in weightlessness. Capsule would be lighter if there is support structure pillars across capsule from floor to top and from wall to wall. The increased lightness of space capsule is more important than more difficult moving of astronauts inside capsule. Rocket motors are made using 3D printing, why not making space capsules with 3D printing, very complicated and complex support structures inside capsule can then be build inside capsule, and those structural support pillars etc are now part of whole capsule structure, not assembled in capsule afterwards. Perhaps fuel tanks also can be build using 3D printing, with honeycomb or other support structures inside tank, or other complex support shapes inside tank that is difficult to assemble other way than using 3D printing.
Another way to use light structure: There is inflatable space stations planned, and inflatable airshields for Mars mission. Why there is no inflatable satellites or inflatable manned space capsules, for example for Mars mission? Inflatable satellite has no satellite bus, but simple plastic package that in vacuum is filled with some amount of air. Air pressure holds satellite together, so satellite is then like plastic bag with air. Inside that bag is satellite components, because bag is flexible it is not so rigid structure like satellite bus, so components inside satellite move slightly, but not much, in weightlessness. Not suitable for astronomical satellite etc. where accuracy is everything, but some satellites can replace rigid composite or metal satellite bus to simple plastic bag style assembly. It is air pressure, not satellite bus that makes satellite more or less rigid. Weight of satellite is now less if satellite bus is made of thin flexible material and air, instead of metal or composites. Inside this plastic bag can be support pillars filled with air, air pressure makes those flexible round tubes / support pillars whose inside is filled with air, structure rigid, when those air filled tubes go through satellite from wall to wall and from top to bottom. In Mars mission the whole living quarters of spacecraft can be made with inflatable structure. Similar air pressure support tubes that are used in inflatable satellite can be used in inflatable spacecraft. Across floors and walls of living habitat goes flexible tubes with air pressure that makes spacecraft rigid. Inside living quarters is less air pressure than in support structure (support pillars). The whole Mars mission capsule living quarters can now be packed in really small package in rocket before launch, only area of astronauts seats during launch are used, but in space capsule is inflated and filled with air and it expands to its proper size. Air pressure holds whole thing together, including tubes filled with air pressure that are support structure of capsule, and those air filled support tubes are inside capsule everywhere, but in weightlessness astronauts can go around of them. Those air filled support tubes can be in every cubic meter of capsule, but crew can “swim” around them in weightlessness. The capsule is now flexible and not so rigid like capsule made of metal or composites, but that flexibility is acceptable. Also air pressure of living quarters, altough it is less than support tubes, helps to keep capsule its shape and rigidness. Also in capsule walls can be higher air pressure than in living quarters, and this high pressure is in air tubes crossing living quarters also, making capsule rigid.
If really cheap space launch system is considered, In India is SHLV and HLV rockets. Instead of USA using billions of dollars for SLS that cost 500 million USD for every launch, cheaper version that uses indian solid boosters grouped around american liquid hydrogen tank can be build. Or surplus space shuttle solid boosters, 2 of them, in indian SHLV rocket, and american rocket engine in final liquid hydrogen stage, so that would be indian SHLV rocket with space shuttle boosters, which there are plenty left after space shuttle program, and american rocket engines. Boosters can be recovered if indian staff does recovery and refurbishing. Indian launch sites can be used and indian personnel for launch preparation and launch. That would be really low cost SLS. Saving of money is huge altough this american - indian version of SLS has less cargo capacity than american SLS (that costs 0,5 billion for each launch).
Also if private funding is needed in private enterprise space projects like SpaceX, Blue Origin etc., there is one source of investment money that is not used yet. Rich middle east countries have money, and their rich oil sheiks too. Countries like United Arab Emirates have money to spend hundreads of millions of dollars, they have so much money that they don t know where to invest it, and space business is one business that needs investment money. UAE and Saudi Arabia etc. countries and their rich people have invested in almost every imaginable earthly project, but they have not invested in space business. And private space business needs money. So is this business opportunity?
Norway has state owned oil fund that has 1000 billion dollars available. Norway has not given any great deal of money to space research, either for research projects or simply investing in private space firms. So Norway s oil fund could invest some of its value to space business also and not all to earthly business only. Also airlines are rich firms, some of them (In USA) have 60 billion dollar assets. Only airline firm that has invested in space travel is Virgin Galactic. In USA is also large number of small space startup firms with big plans but small amount of money. Because space travel is the future way of travel, why rich airline firms don t invest to future and invest to those space startups that can have big business if they just could get money from investors. Rich airline firms have up to 60 billion dollars so money is not a problem. Air launch type systems like Svityaz in Ukraine and in Romania ARCAspace use airplanes, so logistics similarities exist (both airlines and air launch to orbit systems use airplanes).
Also more energetic rocket fuels can be used. In 1960s was developed liquid rocket fuels that actually were liquid explosives and unsuitable for rockets because they tend to explode them. Also liquid gun propellants have been developed. Using those in hardened rocket nozzle that can withstand the blast can make very economical rocket engine / rocket. Even most effective solid explosives could be used as rocket fuel, if small pellets are fired at the rate of 1000 - 6000 rounds per minute (16 - 100 rounds per second) in bell shaped nozzle. System is similar to fast firing automatic cannon, “gun barrel” is rocket nozzle. Perhaps recoil absorbing system is not needed if vibration of “shots” does not shake rocket too much, but if recoil is too much, similar recoil absorbing mechanisms that guns and cannons have, recoil springs or other kind of suspension (hydraulic?), or similar that nuclear pulse propulsion rockets have, can be used in rocket nozzle connection to rocket, altough those explosive - powered rockets use ordinary solid explosives. Also using many high explosive - powered rocket engines, 37 - 30 in first stage like BFR and N1 rockets, and in last stage about 9-12 or more rocket engines, “shooting cycle” between engines synchronised so that vibration load per second is low enough that rocket structure can withstand it without recoil absorbing mechanism. The most powerful high explosives can then be used as rocket propellant. One rocket engine chamber could use many rocket nozzles if that is needed, rocket nozzles like horns grouped at chamber exhaust. If high explosive is used as rocket fuel only bell shaped nozzle is needed and and explosive exploded inside this bell. There is nowdays many very high strength but light materials that can withstand explosion in rocket nozzle, if many rocket nozzles (even more than 37, perhaps 50 or more?) are used and fast firing cycle of small explosive loads.
If high explosive like CL20 is put to firecracker string and then this fireceracker string exploded inside rocket nozzle, now instead of one big blast is large number of smaller explosions in slightly different time so that makes explosion pressure smaller, instead of one big pressure peak is several smaller, so total thrust of recoil stays the same inside nozzle. This firecracker belt or string can have 100 - 500 explosions per second, all timed to explode at slightly different time, providing constant thrust inside rocket nozzle. Simple system that feeds this firecracker belt to rocket nozzle is only needed. Varying belt feed and starting of their fuses brings variable thrust, altough propellant is solid explosive. Inside rocket fuel tank is long firecracker belt. If larger explosive cartridges are used, big like artillery cartridges and not firecracker type, shaped charge can be used in first booster stages and core stage. Shaped charge turns explosive energy to opposite direction where rocket goes, so almost all explosive energy goes to rocket recoil thrust. Perhaps rocket nozzle is not even needed. When rocket rises higher there is no air pressure so vacuum cone of shaped charge does not work anymore and rocket changes to explosive cartridges that have no shaped charge. Cartridges can be made caseless so they burn away, including vacuum cone of shaped charge, or made of some light material like graphene hardened epoxy. System is like fast firing automatic cannon. Enchanted blast explosives or similar explosives that underwater explosives like torpedos and underwater mines use can be used. Or CL20 or other very effective explosive. First stage can use shaped charge explosive type and second and third stages firecracker type belt feed for example, or just firecracker belt in all stages
If using explosives either as solid or liquid form is not possible, is possible to use hybrid rocket, “high energy density matter” HEDM rocket fuels, metallic hydrogen, trinitramid, ALICE aluminum rocket fuel etc. “Metal powder: the new zero carbon fuel?”, “Unsaturated hydrocarbons to increase energy density of methane rocket fuel”, “Highly powerful new biofuel could change rocket engines forever”, “High volumetric density rocket propellant” pat 20170183223, “Review on synthesis and properties of high-energy density liquid fuels: hydrocarbons, nanofluids and energetic ionic liquids”, “From rocket to rocket fuel: plant waste could power planes”, “A new look at rocket fuels”, “Greener space travel? scientists unlock the door to cleaner rocket fuel”.
“Why not fuel rockets externally during liftoff” 2017. If up to 500 - 600 m high tubes / hoist is connected to rocket boosters and core stage and they pump fuel up o 600 m high, so rocket has full fuel tanks altough it is 600 m from ground and gaining speed (rocket equation). Fuels must (?) be non-cryogenic, but now is invented safe and energy rich non-cryogenic rocket fuels. First stage can use them. Or other oxidiser than oxygen and kerosine etc? Also safe bipropellant solid fuel (powder?) has been invented, so fuel powder is pumped to rocket during liftoff, or firecracker belt of explosives, or explosive cartridges elevated up to 600 m high to rocket. In 500 - 600 m high fuel tubes / hoists are disconnected. In ALICE rocket only water is perhaps pumped up to 600 m.
Electric solar wind sail and rocket sled rail launch are other propulsion methods in space and ground, “Autophage rocket” patent. In mountain top rocket sled rail launch can be very effective. If sled uses rocket propulsion too, simple cheap liftoff rockets like airplanes use during liftoff in aircraft carriers and those booster rockets are reusable.
Also rocket balloon launch is proposed, 10 - 30 ton rocket lift with balloon. When those balloons are not used to lift rockets they can be used to lift astronomical telescopes weighting 10 - 30 ton to upper athmosphere, their main mirrors can be inflatable “air mattress” membrane type. Orbital airship project that has large airship at 42 km high can also be used to lift telescopes and other scientific instruments up to that high.
I think firecracker belt rocket is neat solution. It can use most powerful explosives available but still if firecracker belt explodes at rate of 500 - 1000 explosions per second (?) each explosion is so small that rocket structure / nozzle withstands it. Also thrust can be varied simply changing belt feed speed to nozzle. However shaped charge cartridges that are like artillery cartridges with vacuum cone, can vector thrust directly away from rocket. Large cartridges can be used when high thrust is needed in launch and smaller cartridge or charge when rocket has high speed nearing space, without vacuum cone because it does not work in near vacuum anyway. Large charge explosions in low altitude can be used because shaped charge turns explosive energy away from rocket nozzle, in high altitude small explosions are used in rocket nozzles that rocket can withstand. If shaped charge works without vacuum, simply making explosive to some shape that creates shaped charge effect is enough, and that works in vacuum, also in high altitude shaped charge can be used. I presume that shaped charge creates recoil force to opposite direction where charge is pointed, if there is no high recoil force (that rocket uses as thrust) then shaped charge cannot be used in rocket propulsion. Or then using shaped charge towards rocket: that would be Project Orion with chemical explosives, over 50 recoil plates, parabolically curved and made with heat resistant material, is in rocket first stage, shooting system launches 16 - 100 rounds per second cartridges from centre hole of each recoil plate, they explode some length away from plate, plate takes recoil from hot gas stream of shaped charge. Over 50 cartridge launch throw systems and recoil plates are needed, each rate of fire 16 - 100 per second, shooted in timed sequence all explosions slightly different time in rocket. Recoil absorbing like suspension of recoil plate or rubber / silicon recoil damper behind recoil plate. Single stage to orbit, air launch or balloon launch or rocket rail sled launch can use those high energy rockets with high explosive propulsion. There is post “High explosives as rocket propulsion” in RH forums, including fuel air explosive rocket.