Questions tagged [rockets]
Questions regarding the boosters or thrusters used to propel man-made objects. For rockets firing opposite the primaries, see [retrorockets]. See wiki for other related tags.
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sending a satellite in the right direction
I suspect that the required accuracy of satellite velocity direction is very high. This is especially the case for low earth orbits.
The radius of the earth is 6400 km. The altitude of a low earth ...
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Need clarification of units on rocket nozzle equation
I have been working on modeling liquid rocket engines and have read the book How to Design, Build and Test Small Liquid Fuel Rocket Engines, I had a question about the nozzle area and the units ...
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Would SLS Block 1B's payload capacity increase if it used 4 srbs instead of 2?If so,how much?
The SLS block 1b could carry 105 tons into LEO.If it used four boosters instead of 2, how much would its payload capacity to Leo and moon increase?
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How could the Soviet Energia rocket go to orbit without an upper stage, and how could it have carried payload to the moon?
The Energia rocket could loft a massive 100 tons into orbit. It could also shoot about 32 tons to a trans-lunar injection. It did not have any upper stage. So, could it really go to orbit and even ...
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Can liquid mercury be used as a reusable rocket fuel? [closed]
If liquid Mercury is changed into solid Mercury thus generating energy and specific impulse why can I not then re-use the solid Mercury as a fuel?
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How can a rocket's self-destruct make for a safer situation than being out-of-control?
On the Sci-Fi Stack Exchange there was a question about implementing self-destruct on spaceships and comparing that to scuttling on naval vessels. One person in a comment said, "They do implement a ...
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What makes aluminum aerospace grade?
So what is aerospace grade aluminum? Aerospace grade and regular aluminum are both aluminum. Do they have a different composition or strength? What makes one aerospace grade and the other one not?
CommunityBot
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Disposing of Obsolete Satellites by Propelling to the Sun
I'm not scientifically adept, so bear with me. Would it be feasible to retain enough fuel on new satellites/space stations, etc., that we could dispose of them when obsolete by sending them to the ...
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Nozzle contour estimation (Merlin 1D Vacuum)
I would like to run a fluid simulation of the diverging section of a Merlin 1D Vacuum engine. While most relevant parameters (such as expansion ratio, flow rate, and nozzle area) are readily available,...
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Are rockets deliberately throttled back towards the end of the burn to spare crew and airframe g-forces?
Throughout its burn, a rocket gets lighter as propellant is consumed. As a result, acceleration (and g-force) increase. In the shuttle, the SSMEs were throttled back towards the end of the burn ...
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Aerodynamically - can a rocket be over 30 meters in diameter?
The past and current designs of rocket launchers have diameters up to 8-10 meters (Saturn-5, N-1, SLS, BFR), up to 13-14 meters for max cross-section dimension for Space Shuttle and Energia-Buran (...
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Are smaller rockets easier to land? [closed]
Is it easier to land a smaller rocket compared to bigger rockets?? Since they are lighter
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Gas generator exhaust for roll control
Can the exhaust from the turbopump of a rocket engine be used for roll control if a rocket only has 1 engine?
Did the falcon 1 rocket control roll this way?
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Single shaft turbopump vs two turbopumps
What are the pros and cons of using same turbopump for fuel and oxidizer and using 2 different pumps for both?
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Does an overexpanded nozzle behave like a suction cup?
It is generally said that, to obtain optimal specific impulse, a nozzle should be just the right size that the exhaust pressure is equal to the ambient pressure. Quoting this answer, a relevant ...
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What was the exhaust pressure of the Saturn V? [duplicate]
I am trying to write some code to simulate rocket launches, and I am doing a proof of concept using the Apollo 11 as a model, to fill my values. When calculating thrust I am using the equation:
F=m⋅Ve+...
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How far has Artificial Intelligence (AI) came in satellites? [closed]
Are AIs being used in satellites? If yes, have they learned to adapt in satellites?
In what way AI has benefited space exploration for us?
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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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What are the major tradeoffs for a launch vehicle having either one 400 kN engine or eight 50 kN engines?
Given the problem of choosing to build and launch a small rocket to put a smallsat into orbit with either of these two configurations, what are the major tradeoffs between them?
For specific issues ...
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Dual expander bleed cycle
Would dual expander bleed cycle be a good idea?
The lox will pass through the nozzle and drive the lox pump
And the fuel will also pass through the nozzle to drive the fuel pump
Both will be expander ...
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Can propellant tanks in a pressure-feed rocket be pressurized by burning the propellant inside those same tanks? Recipe for Ka-BOOM?
Pressure-fed liquid fuel rocket engines use pressurized propellant tanks to deliver propellant to the combustion chamber, rather than pumps. This eliminates the mass, cost and complexity of the gas ...
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How to calculate the tank boost system for the displacement feed system?
There is a liquid rocket engine running on two components: highly concentrated hydrogen peroxide and kerosene, fuel vapor is ...
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How can I determine characteristic length (L*) of a rocket engine combustion chamber if there is little to no data collected on a similar engine? [closed]
I am designing a liquid bi-propellant rocket engine using Nitrous Oxide and Isopropyl Alcohol. I have all the necessary parameters for nozzle design and am at the stage of determining the combustion ...
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What is the significance of a heat flux value of 1135 W/m^2 when jettisoning the payload fairing? [duplicate]
I have seen that many rockets jettison their payload fairing at an altitude where the aerothermal heatflux is leass than or equal to 1135 W/m^2. What is the reason behind considering this particular ...
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Are cold gas thrusters viable for model rockets?
Lately I've been exploring the idea of cold gas thrusters, or in this case cold gas rocket engines, to be used in model rockets.
I've read that nitrogen gas can get 73 seconds and helium can get 2.5 ...
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Could a “solar gravitational synchrotron ” use solar thermal rockets to "powerslide" spacecraft out of the solar system?
Could a “solar gravitational synchrotron ” use solar thermal steam rockets to launch spacecraft out of the solar system?
Solar thermal steam rockets https://en.wikipedia.org/wiki/Steam_rocket have ...
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Do rocket exhausts produce an electromagnetic signature to allow remote sensing of said rocket?
Rocket exhaust contains ions, the composition of which varies depending on temperature and fuel. https://arc.aiaa.org/doi/10.2514/3.27825 and https://www.eucass.eu/doi/EUCASS2017-434.pdf
Figure 12 : ...
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Amateur satellite launch
Has there ever been a successful satellite launch done by amateurs? I mean both building the satellite and a rocket to carry it.
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How do you approximately calculate the center of pressure during flight? [duplicate]
I'm working on a simulator for landing the falcon 9 booster rocket. I'm aiming to incorporate aspects like the effects of restorative torque. However, I've been trying to figure out how to determine ...
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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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Does launching a device into orbit change earth's orbit?
Does launching a space shuttle or rocket change the earth's orbit?
After all, to get momentum in space you need to throw something out.
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What is the most promising fusion technology for rocket propulsion?
Given current fusion technology (barely above q=1 as of the 12/12/22), is a fusion plasma torch rocket engine viable?
I'm asking in terms of basic science, not engineering, as I know this would ...
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Has asparagus staging (fuel crossfeed) ever been studied by a space agency?
There are two known examples of fuel crossfeed: The Space Shuttle and the Atlas. The Space Shuttle had fuel lines running from the ET to the main engines. Meanwhile, the Atlas fed fuel from a main ...
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What determines rocket height/width?
I was wondering what determines the height/width ratio of a rocket? What are factors that influence the choice between a tall skinny rocket like Falcon 9 or a wider shorter (in ratio) like Ariane 5 or ...
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Why was Booster 9's 29 engine static fire ended 2.36 seconds early? [duplicate]
Suggested by Darth Pseudonym in answer to my other similar question. Recently (August 7), Booster 9 conducted a static fire test where it shutdown after only 2.74 of the planned 5 seconds of burn ...
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Why were 4 engines shutdown prematurely during Booster 9's static fire?
Recently (August 7), Booster 9 conducted a static fire test where it only ignited 29 of 33 engines. This is the big static fire, there not another one. I have found that they were shutdown prematurely ...
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What is missing in the conversion of specific impulse from units of seconds to thrust/mass flow rate? [duplicate]
I was trying to get the Specific Impulse of the Saturn V engines, hoping for a value in N/kg/s, as I need to know the mass consumption rate per thrust value. Any and all sources give me the value in ...
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Why does this formula say rocket efficiency depends on velocity?
Wikipedia gives the following equation for the efficiency $\eta_p$ of an engine here:
$$\eta_p= \frac {2\, (\frac {v} {v_e})} {1 + ( \frac {v} {v_e} )^2 }$$
where $v$ is the rocket speed and $v_e$ ...
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What caused the H3 rocket to squeal so loudly after its launch abort?
Immediately after the H3 rocket's first launch attempt was aborted, a loud squealing noise could be heard on the live stream. What was this?
The only thing I could find about it when searching the ...
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Why are the very reliable rockets Atlas V and Ariane V not rated for human flight?
During the last ten years all 100 or so launches by Atlas V and Ariane V together have been successful. (One Atlas V payload entered too low orbit, but that would hardly have risked the life of a crew)...
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Is there a rocket that is publicly in the process of being certified to carry nuclear payloads to space?
As it currently stands in the US, only 1 rocket has the proper certification to carry a nuclear payload to space, and that is Atlas 5. (At least, this was my last knowledge). Atlas is nearing end of ...
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Horizontal transportation of space rockets
Inspired by this picture from Does this Soyuz vehicle burn coal or oil? What is its official name?
and related to
What are the advantages and disadvantages of assembling a launch vehicle ...
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Why doesn't NASA release all the aerospace technology into public domain?
NASA is a publicly funded US governmental agency, yet it does not seem to release all the technology it develops into public domain for people being able to study it and learn from it. For instance, ...
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What is the cheapest/simplest way to deliver a camera to the moon? [closed]
The primary objective is this: to deliver a camera to the moon that live streams to Earth throughout the journey AND once it arrives on the moon.
A bonus is if it can then move around on the Moon.
An ...
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What are some good softwares to simulate rocket trajectories ?
I am working on a college project which is based upon a experimental sounding rocket and it would be really helpful if the community could refer me good softwares to simulate trajectories of a rocket.
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Does thrust depend on rocket chamber shape?
I mark with green part of rocket which produce forward thrust and with red backward thrust. integration of pressure around rocket walls gives total thrust,which always act in forward direction..
Does ...
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Contraction Ratio Impact on Performance for Liquid Rocket Engine
How does one go about calculating the necessary contraction ratio (combustion chamber/nozzle throat cross sectional areas) of an engine with these parameters known...
thrust
nozzle throat area
mass ...
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European orbital rocket companies?
Besides the obvious
Arianespace (France) with Ariane 5/6
Avio (Italy) with Vega/Vega C
I found a few other new companies that haven't launched yet (to my knowledge), such as
RFA (Germany)
Isar ...
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How to find the correct size and angle for a conical nozzle on a rocket engine? [closed]
So I need to know the equations for finding the size and angle for a conical nozzle. I am making a rocket engine and I decided the conical nozzle would be the easiest to build. The rocket is going to ...
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How far have autophage rockets been developed?
Ars Technica reports on a May 24 phys.org press release/precis on a University of Glasgow paper in Journal of Spacecraft and Rockets about a solid rocket intended to consume itself during use rather ...
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