Questions tagged [fuel]
Questions about rocket oxidizer, propellant, reactive mass, or other fuels used in spacecraft or rockets.
453
questions
6
votes
1
answer
264
views
Can Falcon 9's fuel be ignited by static discharge?
Reading Twitter comments about the recent Falcon 9 pad explosion, some postulated the problem was that a static discharge ignited the fuel as it was being loaded.
Since TEA-TEB is required to ignite ...
- 741
6
votes
3
answers
306
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.
- 499
6
votes
1
answer
730
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?
- 19.6k
6
votes
1
answer
508
views
SpaceX Webcast - What is visible in this clip? [duplicate]
I've just watched the SES-9 Launch Webcast and was wondering what is visible at about 37:15?
Does the Falcon 9 have cameras in the kerosene (or LOX) tank?
- 163
6
votes
1
answer
197
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 ...
- 163
6
votes
1
answer
751
views
The practicalities of a rock sampling mission to Venus
The planet Venus has hostile conditions: a surface temperature of 462 °C, a corrosive atmosphere and a surface atmospheric pressure 92 times that of the Earth.
During the Soviet era, the Russians ...
- 13.1k
6
votes
1
answer
805
views
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-...
- 301
6
votes
1
answer
726
views
Are the APUs on the SLS SRBs planned to be hydrazine powered?
I recently read that the Space Launch System core stage, which uses renamed / slightly reworked Space Shuttle Main Engines and therefore requires a hydraulic system to service said engines, will use ...
- 182k
6
votes
1
answer
85
views
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 ...
6
votes
0
answers
548
views
How long does it take to chill the LOX and RP1 for Falcon 9 V1.1 Full Thrust?
The new version of the Falcon 9 v1.1 Full Thrust, or as SpaceX would like everyone to start calling it "Falcon 9", uses super cooled LOX and RP1 to improve the density of the fuel for better ...
- 79.6k
5
votes
2
answers
2k
views
Why does Juno use "mixed oxides of nitrogen" oxidizer for propulsion? Which ones?
In the recent Spaceflight 101 article Rocket Burn postponed for NASA’s Juno, to remain in elongated Jupiter Orbit until December it says:
Juno uses a bi-propellant main propulsion system with ...
- 149k
5
votes
3
answers
529
views
Have any rocket fuel systems actually been explosive, and could have detonated proper?
Never mind that this is the 18th question to have the rocket-explosion tag.
To the question "Would the Dragon escape pod have survived this event?" asked about the AMOS-6 mission, Elon Musk ...
- 149k
5
votes
2
answers
497
views
chemical propulsion with separate fuel and propellant?
In most of chemical propulsion engines the product of burning fuel and oxidizer is the propellant; in some cases the ratio between the two is non-ideal, in which case some unburnt fuel acts as ...
- 55k
5
votes
1
answer
515
views
Does peroxide spontaneously decompose when introduced into hot combustion chambers?
I understand that hydrogen peroxide (HTP) can be decomposed into superheated steam and oxygen using a catalyst, but I haven't been able to find any information on whether or not it will decompose in ...
- 822
5
votes
4
answers
862
views
Remaining fuel estimation/measuring Strategy in a spacecraft
During descent of a spacecraft to any planetary body the spacecraft uses retro engine with variable throttle to reduce the vehicle velocity to zero at touchdown.
Inorder to compute for the amount of ...
- 2,911
5
votes
2
answers
1k
views
How would E85 work as rocket fuel?
In the question Can I make my own RP1? the comments talk about using ethanol and water as rocket fuel. That made me wonder how well easily availible ethanol fuel for cars such as E85 (85% ethanol 15% ...
- 1,798
5
votes
1
answer
317
views
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 ...
- 229
5
votes
1
answer
660
views
Why did the Space Shuttle dump excess fuel from the external tank?
In his recent video, Scott Manley mentions that after reaching orbit, the Space Shuttle would dump the excess fuel left in the External Tank before jettisoning it:
...
- 1,326
5
votes
2
answers
257
views
Chandrayaan 2: How has life of the orbiter increased from 1 year to more than 7 years?
https://timesofindia.indiatimes.com/india/chandrayaan-2-orbiter-has-life-of-7-yrs-95-of-mission-accomplished-isro/articleshow/71026990.cms
The ISRO Chairman has reported that the economic use of fuel ...
- 123
5
votes
1
answer
350
views
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.
- 3,288
5
votes
1
answer
1k
views
Why can't an expander-cycle engine be built to use RP-1 or other non-cryogenic fuels?
The expander cycle family of rocket-engine power cycles involve using waste heat from the engine's combustion chamber and/or nozzle to vapourise some or all of the engine's fuel, and using the now-...
- 4,157
5
votes
1
answer
211
views
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 ...
- 21.6k
5
votes
1
answer
172
views
Why does it take Spaceway 1 (satellite) two or three months to dump 73 kg of bipropellant?
I read on https://arstechnica.com/information-technology/2020/01/directv-races-to-decommission-broken-boeing-satellite-before-it-explodes/ (mirror):
In the time available, DirecTV said "it will be ...
- 1,164
5
votes
1
answer
589
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 ...
- 2,798
5
votes
1
answer
324
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?
- 357
5
votes
1
answer
281
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 ...
- 352
5
votes
1
answer
2k
views
Odor of a rocket launch?
Thinking of the primary propellants used for typical rocket launches (such as Hydrogen, RP-1, solid fuel), what are the odors of the exhaust and burned fuel components? I'd think that the Hydrogen ...
- 2,798
5
votes
2
answers
145
views
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 ...
- 213
5
votes
2
answers
891
views
Why is rocket engine flame usually clear/transparent at the nozzle?
This is a followup to a question about why the Falcon 9 second stage flame was invisible when out of the atmosphere. See: Why is the flame of the Falcon 9's 2nd stage invisible?.
That was well ...
- 365
5
votes
2
answers
5k
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 ...
- 311
5
votes
1
answer
465
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 ...
- 2,246
5
votes
1
answer
415
views
Why did the "Secretive SpaceX Zuma Launch" make a big "S" or yin-yang shape in the sky?
The Space.com article Strange Sky Spiral May Come from Secretive SpaceX Zuma Launch shows images from this Tweet and this tweet, the second of which was posted by Dr Marco Langbroek (@Marco_Langbroek):...
- 149k
5
votes
1
answer
2k
views
Would (theoretically) metastable solid metallic hydrogen even need an oxidizer?
In this answer there is discussion of some research on the potential, future use of a solid metallic hydrogen phase that would be metastable at ambient pressure as a rocket propellant. The work is ...
- 149k
5
votes
1
answer
1k
views
What factors are influencing a woosh rocket?
I asked this over at Physics, but no one seemed to know, so I'll try here:
If I fill a plastic bottle with a small amount of rubbing alcohol, shake it around and hold a match to the bottle neck, I'll ...
- 237
5
votes
1
answer
166
views
What temperature difference do the injectors in a cryo engine experience?
A quick follow-up to Does ISRO's Cryogenic Upper Stage have restart capability?
What temperature difference do the injectors in a cryo engine experience between the propellant tank, and the ...
- 13.6k
5
votes
1
answer
956
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 ...
- 5,485
5
votes
1
answer
243
views
How much energy does it take to extract water from silicate?
Browsing Asterank, it seems that people believe many asteroids have large amounts of iron or magnesium silicate. These compounds may come in a hydrated form which contains water, but it is chemically ...
- 245
5
votes
1
answer
270
views
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 ...
5
votes
0
answers
128
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 ...
- 9,387
5
votes
0
answers
212
views
What is the droplet size that is desirable for pintle injectors?
The pintle injectors tend to generate droplets after impingement of the fuel and the oxidiser stream and I understand that the droplets will be premixed.
In such a case, even a larger premixed ...
- 4,469
5
votes
1
answer
2k
views
What "green" propellant powers Curie, the engine on RocketLab's payload kickstage?
Upon news of RocketLab's successful flight of the Electron launch vehicle, it was announced that not only had they deployed the three onboard payloads into the desired orbit, they had done so using a ...
- 8,931
4
votes
5
answers
600
views
Will mining water on Bennu for travelling to Mars not be more economical than mining it at the lunar south pole?
Bennu is a carbonaceous asteroid that is currently accompanied by the OSIRIS-REx spacecraft that will take samples from it to return to Earth.
Its diameter is 490 m. and it is slightly denser than ...
- 7,545
4
votes
2
answers
3k
views
Is there a chemical propellant combination with Isp between Methalox and Hydrolox?
Methalox rocket engines (Liquid Methane and Liquid Oxygen) have theoretical specific impulse in the high 300's.
Hydrolox rocket engines (Liquid Hydrogen and Liquid Oxygen) have theoretical specific ...
- 1,033
4
votes
1
answer
2k
views
Is it correct to say that a LH2/LOX rocket uses water as propellant?
The title more or less sums it up.
A rocket engine works pretty much by combining fuel and oxidizer, and expelling some propellant resulting in foward motion as described by Newton's third law of ...
- 7,310
4
votes
2
answers
504
views
Could H₂S₂O₈ (peroxydisulfuric acid), made in the clouds of Venus, be used for making a propellant?
The salts of the peroxydisulfate ion, S$_2$O$_8$$^2$$^-$, are strong oxidants like the perchlorates that are used in propellants for rockets.
In this answer on Chemistry stackexchange is a link to a ...
- 7,545
4
votes
1
answer
2k
views
What fraction of a liquid rocket launching from Mars to return to Earth would be fuel?
I've tried to get my head around this and have decided that, for the moment, I don't want to learn to solve logarithmic equations. Too much else going on.
I was reading Mars Direct and got the ...
- 21.4k
4
votes
2
answers
550
views
How could a hydrazine and N2O4 cloud (or it's reactants) show up in weather radar?
Question: How could a hydrazine and N2O4 cloud (or it's reactants) show up in weather radar?
Tweet:
This is what an ‘anomaly’ looks like on weather radar.
Tweet (with GIF):
Dragon's static fire ...
- 149k
4
votes
1
answer
276
views
Why is LOX on top in the Space Shuttle external tank instead of the other the way round? [duplicate]
Why is oxygen placed on top of hydrogen? Does this have anything to do with letting the warmer and not the colder liquid have a non-spherical bulkhead and thus more surface area to reduce boil-off?
- 1,338
4
votes
1
answer
4k
views
What is the spherical tank in this drawing of the BFS?
The big news in this article is the extremely large carbon-fiber fuel tank. However, the drawing in the article does not show it well. Instead what stands out like a sore thumb in the drawing is the ...
- 149k
4
votes
4
answers
20k
views
What is the formula to calculate how much fuel is needed for a rocket?
I'm theoretically trying to launch a rocket for a school project and therefore I chose Saturn V. I took its weight of 140.000kg (308 647 pounds) and I'm trying to calculate how much fuel it'd take to ...
- 51