Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
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How cheap would rocket fuel have to be to make Mars colonization feasible (according to Musk)?
Elon Musk tweeted recently:
Currently, launching Falcon Heavy costs \$90M. \$0.5M of this cost is fuel. But if technology costs were reduced by a factor 10,000, as Musk wants (through reuse, ...
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Fuel above oxidizer or oxidizer above fuel? [duplicate]
If you look at several mainstream rocket designs (i.e. Shuttle, Falcon, SLS, and even the first stage of the Saturn V) within each stage the liquid oxygen tank (blue) is placed above the liquid ...
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Starliner: Deorbit with Service Module RCS thrusters?
I have read that as a fallback option, the service module's reaction control system (RCS) thrusters could be used to deorbit the craft in case the normally used "orbital maneuvering and attitude ...
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Are there any rockets that leave extra fuel as a backup?
Are there any rockets that leave extra fuel as a backup? For this purpose I mean fuel that is not intended to be used at any point during the mission. I’d imagine this could be useful in case of a non ...
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What's the highest ISP that a chemical rocket could achieve without using propellants maintained at cryogenic temperatures?
This is related to my earlier question about capturing an asteroid. If you wanted to place an interceptor rocket in space and the purpose of that rocket is to wait for a long time, and then launch to ...
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Would that asteroid transport be possible?
I did the mistake of watching an episode of the Science Fiction series "For All Mankind". There they are trying to catch an asteroid in order to bring it back to Mars. I know this series is ...
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Does Starship run on Slushies?
Cryogenic slush (a mixture of liquid and solid) can potentially store propellants at higher density than cryogenic liquid. For instance, hydrogen slush is 16-20% denser than liquid hydrogen. https://...
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Theoretical viability of a liquid rocket engine concept [closed]
[DISCLAIMER: I am an aerospace engineer undergrad and I do NOT want to build this. I wanted to come up with an alternative for the usual hypergolic mix so US military personnel would have one less ...
user54710
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Why are nitric acid and hydrogen combinations not used as rocket fuel?
I was recently doing a chemistry assignment about bond energy when I noticed the incredibly low bond energy of nitric acid. Given the high bond energy of a nitrogen triple-bond, this set me wondering ...
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How is SpaceX planning to avoid fuel sloshing on IFT3?
SpaceX is about launch IFT3 and during IFT2, the booster exploded probably due to sloshing and an engine having something block its fuel supply.
What has SpaceX changed to avoid fuel sloshing?
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Hydrazine and liquid fluorine as a semi-cryogenic storable lunar space propellant
The use of liquid fluorine as an oxidizer diluted with liquid oxygen has been tested, but wasn't flown, by Bell and Rocketdyne, seperately.
http://www.astronautix.com/l/lf2hydrazine.html
It was ...
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Is there any satellite that uses LOX as oxidizer?
With Liquid Oxygen being used as an Oxidizer in Starship and some other rocket engines, I was curious if LOX was also used for propelling satellites as well.
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Propellant consumption of Starship trip from NRHO to Mars
People, I am trying to estimate the amount of propellant (liquid oxygen+ liquid methane) required by Starship to reach Mars from NRHO (Near-rectilinear halo orbit).
Also the propellant consumption ...
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Force Constant of liquid propellants, RP-1 >1200 kJ/kg
I am familiar with testing of the force constant for solid propellants using the closed bomb test.
But what test method is used to obtain the force constant of liquid propellants?
And is the force ...
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Are there any storable non-hypergolic oxidizers?
Any list of bipropellant rocket fuels I've come across has oxidizers that are either cryogenic (liquid oxygen), hypergolic (nitric acid), or both (liquid fluorine). Are there any practical rocket ...
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Do the flames from a rocket cast a shadow, and, more generally, does the rocket exhaust cast a shadow?
Also, would there be any difference between shadows cast by the exhaust from a rocket as opposed to the flame from a rocket?
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What should be the fuel mass of a hypersonic (Mach 7) rocket using APCP fuel that would deliver a 50 gram payload?
Well, I used this rocket calculator besides asking ChatGPT and BingGPT and both gave me similar answers where the amount of fuel would be around 300 to 4000 grams of APCP fuel. And 30 to 100 grams for ...
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What kind of propulsion did/does the Raytheon EKV vehicle use?
Raytheon has developed an Exoatmospheric Kill Vehicle, designed to intercept an ICBM and destroy it through a collision. Here are some related links:
Wikipedia page
YouTube video about the project, ...
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Methane vs propane as rocket fuel [duplicate]
How would propane compare with methane as rocket fuel?
Propane can also be stored as liquid under pressure.
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Can hydrogen peroxide and propane be a good rocket propellant combination?
The decomposition of hydrogen peroxide can be used to spin the turbopump and then it can be mixed with propane in the combustion chamber
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Computing Flight Characteristics for Different Propellant Grain Geometries?
Consider the following image:
I am interested in mathematically accounting for some of these different geometries but have had little success so far in finding how this can be done. The first thought ...
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Do larger rockets tend to have a better mass ratio due to the square cube law?
Do larger rockets tend to have a better mass ratio due to the square cube law? I mean, larger tanks have a better surface-to-volume ratio, so their weight-to-volume should be improved
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Which are more efficient: oxidizer-rich or fuel rich rocket engines?
Several internet articles claim that the high Isp of the Soviet RD-180 engine (as used in the Atlas III and V launch vehicles) was (at least partially) due to the fact the RD-180 ran oxidizer-rich, ...
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Hydrogen-propelled space elevator [closed]
I'm working on a space elevator design using kerosene-burning jet engines and dirigibles supporting 1km stages of pipeline and cable stretching up to the end of the stratosphere (~50km), then using ...
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How does SpaceX prevent fuel from cluttering together in zero G [closed]
What is the solution to stop fuel inside starship collecting in center of the tank during zero G flight? Here is a rough sketch of starship with rudimentary diaphragm system to control flow of fuel ...
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Non-Cryogenic Propellant Transfer
I know there are programs like the Rocket Lab CryoSat, but I was wondering if there have been any tests of non-cryo propellant transfer?
I know the Space Station refuels with a storable hypergol, but ...
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Semi-Cryogenic HTP/LH2 engine?
Also see HTP as oxidizer for main propulsion
(for more info on history of H2O2/HTP in rocketry)
Note: HTP and H2O2 will be used interchangeably
I know the Black Arrow LV (The first orbital lipstick) ...
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How do you find the burn-time of a specific solid rocket fuel?
I read this post about finding the propellant mass needed to reach a specific altitude: How do you find the propellant mass needed to reach an inputted altitude?(altitude at end of burn plus altitude ...
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What is the A in the mass flow rate formula for solid rocket propellants? How do I get the chamber pressure? [closed]
I believe the mass flow rate formula for solid rocket motors is:$$\dot{m}=p_pA_br$$ What is $A_b$ in this case. Is it the cross-sectional area of the hole in the grain? What is there is a nozzle? What ...
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What would it take to collect methane from the atmosphere and use it as rocket fuel?
SpaceX is currently dealing with a lot of environmental regulation issues with Starship. One issue they have is the amount of CO2 Starship produces. Their falcon 9 produces 440 tons of CO2 each flight,...
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Debunking Apollo 11 based on the fuel usage [duplicate]
I have checked the NASA docs and it says they needed hundred thousand liters of liquid hydrogen for the various stages of the Apollo 11 mission. For example stage 2 was calculated to need at least ...
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Rough values for the staytime or characteristic length of the combustion chamber of an oxygen/methanol rocket engine?
I'd like to have some idea of the staytime or characteristic length of the combustion chamber of an oxygen/methanol rocket engine.
Are there sources for this, or a way to estimate it?
I've tried, but ...
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Would reaching an elliptical orbit with the same mean altitude as that of a circular orbit require the same amount of fuel?
Would a rocket that wanted to reach an elliptical orbit with a perigee of 100 miles (160 km) and an apogee of 300 miles (480 km) burn the same amount of fuel as a rocket that wanted to attain a ...
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Going over the Apollo fuel numbers and I have many questions
I was reading through Apollo by the numbers and I noticed the LM descent to the moons surface consumed 17,414kg of fuel out of a total of 18,184kg leaving only 770kg of fuel.
But then in the very next ...
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Multi-stage combustion products?
Okay so I've never seen anything about this before, and that's probably for a very obvious, very simple reason I am far too dim to think of, but here goes:
Most combustion reactions in rocket chambers ...
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Deep space mission propellant
For an interplanetary mission that has a duration of 40 years cam we use hydrogen peroxide monopropellants? Can we use arcjets?
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Propellant choices for a Mars landing; tradeoffs between LOX/CH4 and H2O2/RP-1?
What are the tradeoffs between LOX/methane and peroxide/kerosene for a Mars landing mission?
In which ways are each better or worse than the other?
I think the second one would more attractive for ...
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How to estimate the fuel required to send 1 kg to lower mars orbit?
Imagine a rocket with a payload of 1 kg. How much liquid fuel would be required to send that 1 kg payload to lower mars orbit. (1 kg is just the payload not the whole dry mass of the rocket) I want ...
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How do space probes find their way and how much fuel do they use to travel?
How do space probes find their way, for example, to explore dangerous planets like Jupiter or Saturn that have powerful magnetic fields? Do scientists control it from stations in NASA or they have a ...
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How was the external tank emptied in a TAL shuttle abort?
One of the numerous reasons RTLS was the least preferred choice is
For a safe separation, the ET must contain a maximum of 2% propellant remaining at Main Engine Cutoff (MECO).
How would TAL do away ...
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Why did the June 2016 SpaceX launch run out of propellant?
In other words, what caused SpaceX to miscalculate the amount of propellant required to safely land the booster. They had landed successfully on the drone ship in April. So what went wrong here? What ...
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Why do the Falcon 9 fairings have soot on them?
On nearly every SpaceX webcast since 2020 they explain that the Falcon 9 booster has soot on it because, during the entry burn, it flies through its own exhaust plume very quickly depositing the ...
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What is the value of SpaceX Starship 1200-ton propellant capacity? Would a fully refueled Starship be able to accelerate to Jupiter (for example)? [duplicate]
2200000N (1 Raptor) / 1,300,000*0.4 kg (Total weight adjusted to fuel loss) = 4.2 m/s^2 (acceleration)
Delta-V (to travel to Jupiter) = 9000 m/s
9000 m/s / 4.2 m/s^2 = 2,142 s (1 Raptor engine ...
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How much of LOX will have to be generated for SpaceX Starship to get back from 16 Psyche?
Mixture ratio for Oxygen/Methane is 3.6 to 1
Liquid oxygen temperature of -183°C
16 Psyche (in shade) -113.15°C (https://simple.wikipedia.org/wiki/16_Psyche)
Looks like the idea of bringing enough ...
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Important new additives to hypergolic hydrazine-based fuels since 1972?
In "Ignition! An Informal History of Liquid Rocket Propellants", John D. Clark in one of the chapters gives an overview of the then current state of hydrazine and hydrazine derivatives.
The ...
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How were inflatable fuel tanks for NASA supposed to work?
When the Washington State University researchers looked through the literature, they came across research that described the development of a bellows that took advantage of origami, the Japanese art ...
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How to account for burned fuel mass when calculating spacecraft acceleration?
I thought I could simply remove half of the burned fuel mass to account for the mass lost during the engine burn.
But I could not find a Newton's Second Law formula Calculator that would allow that, ...
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What engine cycle is best for a large lunar lander?
I'm specifically looking for an answer to whether a pressure fed or pump fed engine would be more feasible considering a mass of over 50T(metric, of course), and a single stage to descend and then re-...
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Calculating propellant mass from total impulse
I have a simple question about how to calculate the total propellant mass used by a satellite in space.
From Simulink, I have a graph of thrust VS time, so I could integrate this to calculate the ...
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How do propellant transfer technologies work?
I'm new to the aerospace world, and I was wondering how the ISS or other rockets were refueled in space. I've found some information, but most were patents and I wasn't able to understand them well.
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