Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
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Why isn't oil used for rockets? [closed]
Most people know that when you add oil to a fire, it grows rapidly and becomes more powerful. So, why isn't added into the propellant just before it comes out of the engine?
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Could a Mars rover go to Phobos or Deimos instead?
Could a Mars rover go to Phobos or Deimos instead of going to Mars? The choice is made after launch, and no further modifications can be made to the rover. Could it land safely? Up to what point could ...
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Ultimate fate of rocket propellant in space?
For many trajectories using engines with moderate ISP such as chemical or nuclear-thermal rockets, the exhaust velocity vector of various space operations is such that the rocket exhaust will end up ...
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What happens to the propellant in a wet dress rehearsal?
The Artemis 1 mission is going to do a wet dress rehearsal where the rocket will be filled with propellant and the launch sequence will continue until almost the last second. The launch sequence will ...
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What is the equation to find how much fuel you need to reach a velocity? [closed]
Theoretically, I need to launch a rocket, and I need to find how much fuel I need to reach a velocity however I do not know the equation.
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What is the equation for fuel equals distance for a rocket? [closed]
Theoretically, I am trying to launch a rocket from space and trying to figure out how much fuel I would need to get to a certain distance.
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Why is monopropellant used?
The most efficent fuel, liquid hydrogen, is a bipropellant. So, why don't we just use bipropellants? Some monopropellants, such as hydrazine, are toxic. Wouldn't it be easier to just use bipropellants ...
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Why do $\text{CH}_4$ (Raptor) engines produce less soot than RP-1 (Merlin) engines?
SpaceX's Merlin engine, which burns RP-1 and LOX, has soot visible after the first stage lands. Many articles on the web say SpaceX's Raptor engine, which burns methane and LOX, is clean. ...
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Using Chimborazo as a rocket launching platform
Please consider this.
Chimborazo is a sleeping volcano at 01°28′09″ S 78°49′03″ W. Its peak is 6263 metres above the sea level and because it is very near of the equator, the peak is more than 2 ...
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Fuel profile for Apollo 11
I downloaded a dozen of NASA documents about post-flight analysis of Apollo 11 mission, but I cannot find a table or a plot of fuel usage and remains;
Some of the documents which I found:
http://www....
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How to convert bi-propellant fuel into Delta-v (for ex., for JWST)
The following news gave the details on the quantity of fuel embarked on JWST: NASA gives green light to fuel the James Webb Telescope.
The Webb telescope’s spacecraft bus, built by Northrop Grumman, ...
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How are JWST tanks baffled to dampen slosh?
After JWST slews to a new orientation, it then needs to “settle” sloshing fuel in the tanks before Fine Guidance System (FGS) can acquire the new science target. The time needed for slewing, settling ...
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Can the higher oxides of nitrogen, like nitrogen pentoxide, be used as oxidisers in rocket engines?
Both nitrous oxide (N2O) and dinitrogen tetroxide (N2O4) are used in storable propellant combinations, so, simply as a continuation, can the higher oxides of nitrogen (N2O5, N2O6, etc.) still be used ...
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What is "anti-geysering" and why would you turn it off 70 seconds before launch?
Today Rocket Lab launched the Electron from Launch Complex 1 Pad A in New Zealand, and there was something about
...the first time a helicopter will be stationed in the recovery zone offshore to ...
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Solid metal fuel for nano satellite thrusters
A South African company is developing a solid metal fuel thruster that was initially researched by NASA but was not further developed,
an electric reaction could be used to vaporise solid metal fuel, ...
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Why don't Raptor engines use CH3Cl instead of CH4?
The boiling point of CH3Cl is -24 degrees Celsius, whereas the boiling point of CH4 is -160 degrees Celsius.
The density of CH3Cl is 2.3 g/cm3, whereas the density of CH4 is 0.6 g/cm3.
CH3Cl is polar, ...
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James Webb telescope; limits to propellant lifetime?
There is a comprehensive article on Wikipedia on the James Webb telescope. It includes a statement regarding the operational lifetime being nominally five years and optimistically ten years. However ...
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Tilted exhaust gases from the rocket nozzle after sonic boom [closed]
Our solid propellant rocket, on test, produces sonic boom. Right after, the plume of exhaust tilts sideways. This will definitely have a gimbal effect during flight. The propellant chamber has one ...
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What is the meaning of "aggregate state" within the context of RPA?
I'm trying to make a new entry in the thermodynamic database of RPA (Rocket Propulsion Analysis, http://w.lpre.de/) and you are required to provide an "aggregate state".
For CEA (Chemical ...
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Decomposing HTP through regenerative cooling for use in closed expander cycle
HTP or high test peroxide has a long history as a low cost and high reliability oxidiser, and has had a lot of recent attention for its pseudo hypergolic nature when passed over a catalyst bed. ...
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Giving rocket propellants an opposite charge for perfect mixing?
One of the challenges in achieving theoretical efficiency is the mixing of both an oxidiser and fuel. This means separating both propellants from each other whilst pairing them with their counterpart. ...
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Using coolant as 3rd propellant
Rocket engines often have 2 propelants, one of which is used to cool the engine and after that the hot propellant is injected in the combustion chamber.
Would make sense to have a third propellant ...
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Silane as a rocket fuel
At about 6:55 into the video Why Moon Mining Will DEFINITELY Be A Thing it is stated that lunar silica (SiO2) could be turned into silane (SiH4), which is the silicon analogue of methane. It also ...
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Does anyone know the stay time, or what characteristic length should be used, for a LOX/LCH4-fuelled rocket engine?
Just what it says on the tin. I need to know either the "stay time" (Ts) or characteristic length (L*) that would be used to figure combustion chamber dimensions used with a LOX/LCH4-...
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Calculating total burn time for a rocket under constant acceleration with two propellant consumption rates
I tried posting this question on the Physics side of StackExchange but didn't get any response after a week, presumably because it was lost within the broadness of physics in general, so I'm hoping ...
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Which burning of Solid Propellant is best axial burning or radial Burning?
Which Burning is Better Axial or Radial of Solid Propellant grain used in Solid Rocket Motors?
How Someone Determines which to choose according to the Mission requirements ?
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Can ion Thrusters be used for Reaction Control System?
As RCS (Reaction Control System) mainly required less thrust than regular rocket engine can ion Thrusters be used for attitude determination in spacecraft(Orion, Dragon), satellites or even during ...
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Does a cryogenic liquid propellant engine exist capable of using multiple fuels?
For example, a rocket engine which can use both liquid methane and liquid hydrogen.
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Did any Apollo missions have enough fuel left to bring back the LM ascent stage?
A recent question asks why the Apollo lunar module wasn't routinely brought back when returning from the Moon, so it could be used as an Apollo 13 style lifeboat. The answers correctly state that ...
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To what precision were the amounts of the Shuttle propellants known? [duplicate]
A previous question reveals that the Shuttle orbiter was weighed before it was moved to the Vehicle Assembly Building. Presumably, the other dry components of the launch stack (the solid rocket ...
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What's The Gas Discharge After Landing Finished For SpaceShip2?
What's the gas discharge after landing finished For SpaceShip2?
Why did they did it right after landing finished while crew were on board.
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How to estimate fuel needed to reach LEO, GEO, and L1 earth-moon? [closed]
I'm doing some calculations about fuel production on the moon.
To get a sense of order of magnitudes involved. I'd like to know how much fuel is required to get 1kg of mass to LEO, GEO, and L1 Earth-...
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Would it be practical to catch a rocket's exhaust to reuse it as fuel?
It's been some days that i think that would it be possible to make a ship that looks like this?
The idea is to catch the fuel as you go.
Would this make any sense or the thrust would be canceled by ...
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Did the flare stacks at LC39 have pilot lights?
The liquid hydrogen fuel in the space shuttles would slowly boil off, while they waited on the launch pad at Kennedy Space Center launch complex 39A or 39B. The hydrogen vapors were removed by the ...
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Use of high energy propellants on an engine designed for low energy propellants
This question is about use of high energy propellants on a rocket engine designed for low energy propellants. In any engine, which is currently working on RP1+LOX, if we change the fuel from RP1 to ...
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In situ Fuel in LEO / MEO
I have been thinking on controlled de-orbiting of Satellites.
You can carry a supply of conventional chemical fuel, and use it to apply a delta-V that would de-orbit them. There are also methods of ...
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Alternative propellants in nuclear thermal rockets
Many years ago, I read a science fiction story "Rocket Ship Galileo" in which a nuclear powered spacecraft used zinc as a propellant. Apart from the fanciful nature of the story itself, I ...
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How much fuel could a rocket save by launching from an airship/blimp?
What could the Kozlov’s Aerosmena project blimp add to fuel saving if space rockets were launched from it? Where would you place the rocket and airship on this chart?
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Why RP-1 and not Methane for Falcon 9's Merlin engines?
I've seen methane described as the best of both worlds---the worlds being hydrogen's energy density + pain-in-the-ass factor and RP-1's lower energy density + ... ease of use?
And this has me ...
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energy needed to accelerate in space
I was thinking about possibility of cargo transport between, say, earth and mars when a “pusher” accelerates propulsion-less cargo vessel, which is catched and decelerated at the other end of ...
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SpaceX Dragon: How many fuel tanks?
I've read that Dragon carries 1380 kg of MMH + NTO propellant. This mass would be split among the various tanks, and I'm wondering---how many of them are there?
Pictures from the manufacturing floor ...
user39728
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Can pyroxene and other silicon compounds be used as a theoretical spacecraft fuel?
I have been reading this patent, which led me to this paper.
The first uses polysilane, which basically replaces the $\text{C}$ in a $\text{-R-C-R-}$ group, making an $\text{-R-Si-R-}$ group. I also ...
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Is CO + O ==> CO2 a possibility for propelling rockets off Mars? [duplicate]
Perseverance, the Mars rover, includes an experiment called MOXIE. This is a technology demonstration to show that Mars' atmospheric carbon dioxide can be broken into carbon monoxide and oxygen. ...
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Why is an inflatable balloon inside a fuel tank not used to prevent fuel from "sloshing around"?
After seeing all the Starship failures, having something with a membrane keep things in place seems like an obvious solution. Has it been considered or tested - or do we simply lack a material that is ...
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Why is hydrogen better than helium as remass?
I just watched a very good YouTube video on why nuclear engines might be useful, and it also goes into why Hall Effect thrusters are super good at squeezing obscene ISP out of things.
During the video,...
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How do you reliably blow up a rocket that was built not to explode?
NASA, and I'd imagine most space agencies around the world, demands abort systems of its commercial partners capable of destroying a rocket should it venture too close to populated areas. Note that ...
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Could another fuel be used in the SpaceX Starship header tank?
A memory of hexane and water in a separatory funnel brought to mind the issue of helium and LNG in the header tank while the Starship flips and does its powered landing.
There was discussion of the ...
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If high-test peroxide is most stable when pure, why are most uses of it in rocketry at lower concentrations?
Per the Wikipedia article for High-test peroxide:
Hydrogen peroxide becomes more stable with higher peroxide content. For example, 98% hydrogen peroxide is more stable than 70% hydrogen peroxide. ...
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What is the O/F ratio of ethanolamine/H2O2?
I've just read this question What is the products of a catalyzed reaction between Hydrogen Peroxide and Ethanolamine with Copper(II) Chloride? and although its a very good question and an excellent ...
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Potential Fusion Drive system calculation issue
I will start off by saying that this is an entirely hypothetical drive system with plenty of handwaving and optimistic physics. My question I think is fairly simple and may just be something that ...
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