Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
12
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2answers
3k views
Can a rocket refuel on Mars from water?
Can a rocket run only on hydrogen and oxygen? Could a rocket, rover, and electrolysis machine be sent to either of Mars' poles to excavate ice to make hydrogen and oxygen to refuel an unmanned rocket?
...
2
votes
1answer
72 views
How to find an optimal number of propellent tanks?
My idea: If the propellent mass to tank mass ratio remains constant when increasing/decreasing the amount of propellant then you could increase $\sum \Delta v$, by splitting the propellent tank and ...
2
votes
2answers
126 views
Break Away Valves for Launch [duplicate]
I forgot to hang up the fuel pump and broke it off and costed around 80 dollars to replace. While there I wandered could this be adapted to a rocket in some way?
How much fuel capacity would be saved ...
4
votes
1answer
74 views
What rocket system launch contained the highest amount of propellent potential energy?
In regards to rocket launches, what rocket launch contained the most potential energy (joules/btu/etc.) in its thrust propellant to achieve is basic mission? I'm not as much concerned with ...
21
votes
7answers
4k views
Pre-mixing cryogenic fuels and using only one fuel tank
A methalox engine is fed from two cryogenic fuel tanks. Why can't the methane and oxygen be mixed as gases, in the desired proportions, and then chilled to a temp that liquefies both? From a single ...
5
votes
0answers
68 views
What rocket uses the largest percentage of Fuel/Oxidizer before liftoff?
inspired by this question: How much propellant is used up until liftoff?
which asks how much propellant (fuel/oxidizer) a typical rocket uses before liftoff. What has been or is the most non-typical ...
9
votes
1answer
1k views
How much propellant is used up until liftoff?
How much of the total propellant mass (fuel+oxidizer) of the first stage/boosters is usually burnt between ignition and liftoff?
0
votes
1answer
115 views
Fuel vs food on the trip to Mars?
How much food for each person is need and fuel per various engine to go to Mars on the current 9-month trip there then 3 months on Mars and the 9 months back? Can time be saved on the trip to and from ...
0
votes
1answer
79 views
What are ways to store hydrogen for electric propulsion without a heavy pressure vessel?
This comment points out that any advantages of using low-mass ionized atomic hydrogen (i.e. protons) for electric propulsion if you had a fixed acceleration voltage and plenty of electrical power ...
2
votes
1answer
43 views
Molecular propellant in ion engines
This question was prompted by discussions on this question. Can there be an advantage to using a molecular propellant in an ion engine, as opposed to noble gasses or iodine? (Although iodine actually ...
2
votes
1answer
165 views
What type of propellant does Spacex plan to use in Starship for long duration missions?
For long duration missions such as ones to mars what type of propellant would be best suited?
2
votes
2answers
290 views
Cheapest rocket to go to space?
Have you ever heard of the old movie Salvage? The TV movie, “Salvage,” aired on January 20, 1979. The film begins with Harry successfully bidding for a vintage bi-plane and then reselling it in pieces ...
4
votes
1answer
74 views
Are there any hypergolic solid/liquid fuel combinations?
Could the principal of hypergolic fuels be applied to hybrid rockets? And if so, are there any known hypergolic solid/liquid combinations?
0
votes
1answer
55 views
Scoutleader looking for understanding of fuel burn for getting away from earth gravity Vs. fuel expended when traveling from A-B in space
I am a layman scoutleader and like to discuss the amount of fuel needed to get from earths gravity to the thrust needed in space to get from A-B. Is there a spreadsheet that would give course ...
4
votes
1answer
144 views
What methods are proposed for storing cryogenic fuels (esp. hydrogen) in space for months or years?
Current Launch vehicles and upper stages must only keep their fuels for minutes or hours, so they are only insulated to keep boiloff to a few % per day - I've seen 21% per day quoted for Centaur on ...
2
votes
1answer
70 views
Hypergolic Propellant Combination
Is Rocket Grade Hydrogen Peroxide and Liquid Hydrogen a hypergolic propellant combination? I recall, seeing the combination somewhere on the www, however I couldn't retrace the source where I saw it.
2
votes
0answers
77 views
What fuels would make refueling in space more dangerous/complicated?
I saw the question:
Has in-space refueling been done?
And was actually beginning to wonder, is refueling and transferring propellant dangerous in space? I understand that this would most likely be ...
10
votes
1answer
2k views
Was there fuel consumption budgeting for Apollo 11 Lunar module?
Did the astronauts aboard Apollo 11's Lunar Module have any stated or imposed limitation or restriction on the amount of fuel they could use while in lunar orbit and performing landing maneuvers? I am ...
1
vote
0answers
140 views
What is the best fuel for bottle rocket? [closed]
I want to modify my firework bottle rocket to fly a mile high. What will be the best fuel for this? Could fuel used in space rockets be scaled down to work in a large bottle rocket?
4
votes
2answers
269 views
What are some notable cold gas thruster propellants, and why?
Cold gas thrusters are a very simple and reliable form of thruster that operate only by spraying a compressed gas, without any chemical reaction.
What are the most common, performant, or otherwise ...
3
votes
0answers
66 views
Falcon 9: how much fuel is left on a booster after stage separation?
If the booster attempts either land or sea landing, how much fuel (RP-1 and LOX) is left in its tanks right after stage separation?
Recently, I have heard numbers as high as 30% of its total tank ...
9
votes
1answer
3k views
How much fuel does the Falcon Heavy use? What is the price RP-1?
Does anyone know how much fuel the Falcon Heavy can hold, the RP-1 fuel and liquid oxygen as oxidizer, and how much of that will it use to get to a certain point?
I don't know how i would calculate ...
6
votes
1answer
171 views
Why did the MarCO space probes use fire extinguishant as their propellant?
In many news articles, it's mentioned that the MarCO spacecraft, launched with InSight, used fire extinguishant as the propellant for its cold gas thrusters. I originally assumed that this was ...
4
votes
2answers
91 views
Propellants used for different Mars landers [till 2018]
What propellants have been used by lander to land on Mars surface?
4
votes
0answers
72 views
Does the pressurization of tanks prevent “liquid sloshing” during maneuvers?
I'll be the first to admit I know little to nothing about fluid dynamics, especially in a pressure vessel. I was wondering how pressurized rocket fuel tanks don't cause weight-distribution problems ...
4
votes
0answers
97 views
How much fuel is left in InSight?
InSight probably landed with some fuel margin.
Unless it was vented/burned on landing (maybe not a bad idea considering potential leaks down the road), is there some left ?
Do we know the ISP of ...
2
votes
1answer
94 views
What could be the proprietary propellant blend that “Apollo Fusion” claims to have developed for it's hall effect thrusters?
According to the info posted on the Apollo fusion website http://apollofusion.com/ , they claim to use a propellant blend that offers " 2-3 X more impulse per mass and volume" in comparison towards ...
3
votes
2answers
161 views
How much fuel to maintain VLEO for communication satelites?
A recent answer about communication satellites in VLEO (≤350 km) estimates a useful orbital life of about month without fuel.
I.e. Once the vehicle is out of fuel to maintain orbit, THEN it has ...
8
votes
1answer
655 views
What percentage of overall fuel does a rocket burn up to get to max-q?
I know that max-q normally occurs around 11-15km (based on observations of watching falcon 9 launches and this). Furthermore, I know that the fuel usage for each rocket would vary a lot (which I ...
5
votes
1answer
169 views
Insulation used in the plumbing line of the actual rockets
While using the pipes for plumbing of the liquid propellants at pretty low temperature because of which ice form on the line if not insulated or poorly insulated, which can lead to liquid to gas ...
3
votes
1answer
82 views
Pressurization line (Helium to LOX tank line) chilling while pressurizing LOX tank
I have read that in rockets and launch vehicles Helium is used for the pressurization of propellant tanks.
What temperature Helium is stored at?
If Helium is stored at room temperature then while ...
12
votes
1answer
520 views
Does the Soyuz spacecraft chemically stabilize the hydrogen peroxide (H2O2) to remain ISS-dockable for 200+ days?
Hydrogen peroxide from the local shop (dilute, 2-3%) sometimes has a stabilizer to slow it's breakdown rate and increase it's "shelf-life", since we'd like to keep it around the house on our shelf for ...
2
votes
0answers
58 views
Is it feasible to take liquid Helium in a Pressure Fed System?
Can liquid Helium be flowed through a heat exhanger to increase its temperature and pressure which will further pressurize fuel-oxidizer tanks.
6
votes
1answer
514 views
Why is ethylene (ethene) not considered as a rocket fuel
In an answer to this question, the brilliant diagram below was given:
The chart makes chilled ethylene look like a very appealing choice, yet I don't believe it is ever used. Why not?
Edit: I just ...
6
votes
1answer
247 views
Curves on Isp/density chart, what varies along each curve?
In an answer to this question, the brilliant diagram below was given:
Each fuel has a similarly shaped curve on the chart. What does that signify? what varies along the curve?
3
votes
2answers
102 views
Do military rockets use the same fuels as their civilian versions?
Some rocket families have been used for both military and civilian purposes (e.g. Atlas). Do the military versions use the same fuel as their civilian counterparts?
4
votes
1answer
175 views
How do they know how much liquid propellant is in a rocket just before launch?
In this answer I wrote:
In other words, a few tons here or there could depend on something as simple as the weather, or trying to squeeze a little extra propellant in for a given mission with a ...
6
votes
1answer
440 views
Russian “kerosene” versus American “RP-1”
RP-1 rocket fuel is a "highly refined form of kerosene". Most of the literature I have seen refers to Russian rockets using kerosene, versus American rockets using RP-1 (*1).
Is there really such a ...
32
votes
3answers
7k views
What is the primary reason for SpaceX motion to have astronauts board Dragon before fueling up the rocket?
News piece: NASA supports SpaceX plan to fuel rockets with astronauts on board.
The move is criticized by many as unnecessarily dangerous.
From what I understand though, it shouldn't be necessary - ...
6
votes
1answer
119 views
Is the atmosphere a positive or a negative for reusability?
Does the atmosphere provide a benefit or detriment in terms of fuel economy for rockets that take off and land back on Earth? We know that the atmosphere plays a large role in helping slow down ...
8
votes
2answers
2k views
Why do Ariane rockets not have ice break off on liftoff?
In a recent question asked here, it was asked what debris falling from a Rocket Lab Electron Rocket was during launch.
e.g.:
The answer, was that it was ice that had formed after cryogenic fuel/...
3
votes
1answer
77 views
Propellant filling rate in propellant tanks [closed]
I want to pump LOX into a pressure vessel at 2 bar (say). So for pumping it what should be safest flow rate?
4
votes
1answer
859 views
Vector-R's LP-1 and -2 engines use liquid propylene as fuel with LOX, advantages and distinctions from kerosene?
@gwally's answer highlights the company Vector Launch Inc. and their Vector-R rocket, which uses three LP-1 18,300 lbf engines on the first stage and one LP-2 1,000 lbf second stage engine to put ...
1
vote
0answers
43 views
Which is preferred for liquid atomization - gas & liquid shear or liquid & liquid shear?
For generating a spray of droplets, liquid need to be disintegrated/atomized through shear forces.
Typical injectors in IC engines and aircraft use shear between gas & liquid at the phase ...
3
votes
1answer
125 views
What is the surrogate liquid for LOx during the preliminary testing of injectors?
Before transitioning to the LOx tests during any new injector development, water is typically used for calculating flow rates, pressure loss, etc.
But testing with water cannot qualify as a suitable ...
2
votes
1answer
115 views
How are the Titan Transtage's tanks protected from its engine?
As a follow up to this answer which identifies the two pointed objects flanking the Titan Transtage's engine in an unusual configuration as its propellant tanks:
How are these protected from the heat ...
0
votes
1answer
115 views
What is the Oxidiser/Fuel Ratio of the Atlas V Centaur Upper Stage?
I can't find this information anywhere for the single or double engine variant. could it be variable? Or is it a secret?
0
votes
1answer
110 views
Could the interaction of the Sun’s solar wind and trapped plasma ions be used to propel a rocket through interplanetary space?
I have recently had a renewed interest in comets and how comet tails are formed. From studying this process, a thought occurred to me that perhaps plasma ions can be created within a long hollow ...
13
votes
1answer
1k views
Why does the 2nd stage of Falcon 9 need compressed He tanks?
It is well known that the rapid disassembly of Falcon 9 static testing started with the rupture of the composite fibres of the copv He tanks.
But what is the need to have the composite tanks ...
2
votes
1answer
78 views
Rocket engine power vs. Sound
Is there any relationship between the sound emitted from a rocket engine and the amount of thrust it gets at surface temperature and pressure?
