propulsion - Are MMH and UDMH interchangeable? - Space …
WEBAug 11, 2013 · Such as Shuttle's OMS (uses MMH), Soyuz DPO (uses UDMH) and ATV's main engine (uses MMH). Both will kill you very quickly and painfully. So in that sense, yes. As propellants, not sure. A great and really funny story of propellants research is John D. Clark. Ignition! (1972) See, in particular, the "Hunting of the Hypergol" chapter.
Why isn't LOX/UDMH used in staged combustion rockets now-a …
WEBAug 1, 2019 · The reason you go with UDMH/NTO F/O pair is storability, i.e. the ability of your rocket or missile to be stored, fully fueled straight from the factory, in a silo or stand on a launch rack for an extended amount of time, possibly years or even decades, and ready to use at a moment's notice, and spontaneous combustion upon contact with no ignition, …
Which is overall more expensive to operate for a final rocket stage ...
WEBJul 19, 2015 · UDMH/N 2 O 4 is extremely acidic, toxic, sensitive to air, and apparently has just about every other terrible chemical property imaginable. It's hard to handle (transport and fuel up), requiring a lot more safety precautions (expenses).
How does the inter-propellant seal works in kerosene/LOX and …
WEBboth propellants are non-cryo, e.g. the UDMH/NTO-fueled RD-275Ms on the Proton? If the propellants are storable and hypergolic and suppose you are a rocket engineer to build one of these engines for military people who want rockets to remain in silos for years and launch at a moment's notice, can you simply turn the fuel/oxidizer main valves to ...
Would symmetrical dimethylhydrazine work as a hypergolic fuel?
WEBApr 2, 2020 · This suggests SDMH is incompatible with oxidizing agents, water. So it can be used for hypergolic purpose.This quote is from Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens: Properties of SDMH. And UDMH is also miscible with water and reacts with oxidizing agent. UDMH is often used in hypergolic rocket fuels as a …
fuel - Why do pressure-fed systems have to be pressurized with …
WEBJun 3, 2015 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Is it true that hydrogen is the only practical fuel for upper stages?
WEBCurrently operating launchers using other fuels for their upper stages include Falcon 9 (RP-1), Soyuz (RG-1 for the 2nd stage, UDMH/N2O4 for the Fregat upper stage), Vega (solid fuels for 2nd and 3rd stages, UDMH/N2O4 for the AVUM 4th stage), and Electron (RP-1).
Why do Russian rocket engineers call C₂H₈N₂ "heptyl"?
WEBApr 10, 2020 · From Wikipedia: "UDMH (which is referred to as "heptyl" [codename from Soviet era] by Russian engineers" If it was a codename, it should not be related to seven carbon atoms. The name should give no information about the compound to the cold war enemies. There is C7H20N2O4S called Heptylhydrazine sulphate.
What is the best chemical rocket fuel from a purely specific …
WEBAug 9, 2022 · Researching this, the main fuel combinations I saw were: RP-1 / LOX (SpaceX's Falcon rockets, early stage Atlas and Saturn rockets), methane / LOX (SpaceX's Starship), HTPB (ISRO's PSLV), PBAN (NASA's SLS boosters), LH2 / LOX (upper stage Ariane rockets and SLS) and UDMH/N204 (ISRO's GSLV). Nevertheless, these fuels …
What was the reason to use different fuel for the Apollo Service …
WEBMay 27, 2018 · $\begingroup$ The "marginal performance difference" between A50 and MMH could well be critical if the CSM's RCS thrusters had to be used to deorbit the spacecraft (the standard backup deorbit method for Earth-orbit missions in the event of an SPS failure) or for the final orbital insertion (a Mode V abort, which was available for the …