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2

In 2018 SpaceX determined that carbon fibre composite material was not going to be suitable for their new BFR rocket due to difficulties with material resilience in different temperature environments and cost. They switched to a Stainless steel design instead and abandoned 2 years of work and tens of thousands of manhours. This had involved building and ...


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There are a lot of variables in this question concerning exactly when an abort is required and what has caused the abort. Some Mars mission profiles can use a free return trajectory. If this is used and for whatever reason it becomes necessary to abort, it is relatively easy to return to Earth by applying a small course correction. This will allow the ...


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#22 - explosive bolt for opening the top cover As you can see in the diagram, the explosive bolt (#22) is in a comfortable environment inside the capsule, protected by thermal insulation (#11). https://epizodyspace.ru/01/2u/solnthe/ams/v-8/v-8.html


6

The Gemini inflatable wing concept took around 4 years and 165 million dollars, and was discarded right at the end, just as they were ironing out the very last issues. The parachute system was used instead, and the wing never flew. The manned manouvering unit was only flown three times before being replaced by the robotic arm due to safety concerns.


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The straight wing concept was perfectly workable. According to The Space Shuttle Decision, Max Faget preferred the straight wing approach primarily because it would optimize performance in the final subsonic approach-and-landing phase. The straight wing would also provide very little lift in the high-speed, nose-high reentry phase, meaning it would fall very ...


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here are some vectors hop this helped (background image from How do Voyager 1's Trajectory Control Thrusters differ from its Attitude Control Thrusters? and What does it mean when the Voyagers "switch thrusters"?)


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Mission Requirements for a spaceplane that are affected by its aerodynamic shape Cross-range capability Gliding range perpendicular to orbital plane on reentry. Otherwise, you have to wait in orbit for the earth to rotate your landing site into alignment with the orbital plane. Flying Qualities How easy the spaceplane is to fly. Landing Speed Safe ...


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The design looks like it was descended from silbervogel, a German world war II project source The twin tails would have been to maintain control at high angle of attack but it appears the advantages of blunt body shapes for re-entry heating control were not understood giving it straight wings with sharp edges. The possibility of a delta design was only being ...


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I believe the "20,000 to 40,000 pounds to LEO" requirement was intended to solicit proposals for launcher families or launchers that could be upgraded from the low end of the range to the high end. In other words, the requirement meant "we want 20,000 pounds to LEO soon, and will probably want 40,000 pounds to LEO later, so give us options for ...


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There is a extensive summary report on possible improvements of solar sail materials: "Ultra-Thin Solar Sails for Interstellar Travel - Phase I Final Report" December 1999, Dean Spieth, Dr. Robert Zubrin When reading this report one has to keep in mind that they only look for the properties of the sail itself, not taking into account structural ...


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A solar sail with an areal density of $1~\mathrm{kg}/\mathrm{km}^2 = 1~\mathrm{mg}/\mathrm{m}^2 =0.001~\mathrm{g}/\mathrm{m}^2$ is impossible by known materials science because graphene has an areal density of $0.77~\mathrm{mg}/\mathrm{m}^2$. Being a single atomic layer of a light atom, graphene is the absolute lower bound for the areal density of pretty ...


7

Either. For the first part, you already answered your question. The main criterion was velocity, because the SSMEs on the orbiter are the second (and orbit insertion) stage of the Shuttle. There's no third stage to compensate for severe under/overperformance (well, there's the OMS, but there's only so much it can do because it doesn't pack quite enough punch ...


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Any spacecraft on upper stages of the launch vehicle is thermally stabilized under the fairing. When the spacecraft is at the cosmodrome, the thermal regime is usually provided with the help of ground-based means. In this photo, you can see two ducts from the fairing to the air conditioner. Air supply to the lower part of the head unit by means of mobile ...


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The basic visible design is usually two Y walls, North and South that carry the baulk of the heat generating equipment, payload or platform, though the latter is usually concentrated at the -Z end. at least two floors, one near the -Z end one near the +Z (Earth pointing) end. There could be additional floors at the +Z end for payload equipment that needs a ...


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