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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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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Thrust & acceleration produced by a rocket engine
For given propellants, with their mass flow decided by the rpm of the turbo pump, what decides the thrust and acceleration produced by a rocket engine? Can we control them independently?
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Has there ever been a fully-reusable big-dumb-booster design proposed?
I know of fully expendable Big Dumb Boosters, as well as "smart" reuse in systems like NEXUS (all versions) and their contemporaries, what I'm trying to figure out (after hours of sorting ...
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What is the simplest rocket design that can reach orbit
I am curious on what the simplest possible rocket design that have been proposed which could reach orbit.
My first thoughts would be earlier rockets like the Atlas LV-3B, but then I consider the ...
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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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Inclination vs payload capacity of a rocket
I am learning about Space exploration and I have the following question:
When you are launching a rocket into space with maximal inclination, is the payload capacity then the highest?
Thanks!
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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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Weird 2010s concept for a helicopter/rocket hybrid
I remember reading in the 2010s about a company that was building a traffic cone shaped rocket that would first ascend to the upper atmosphere with helicopter blades attached on the tip, then retract ...
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Why do rockets have to be pressurised? [duplicate]
I understand why an engine like the AJ10 needs pressurisation to feed it fuel, but why does a stage like the S-IVB/ J-2 need it if it has turbomachinery?
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Rocket maximum distance [closed]
let's say I have a liquid rocket
what would maximize the distance traveled by the rocket thus consume less fuel
constant velocity or acceleration or why?
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Powered Explicit Guidance - Why wouldn't it be used?
I keep reading that the Powered Explicit Guidance equations (PEG) (detailed in the Technical note linked below) is (an approximation of) the most efficient way to get to space. That being said, I know ...
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Could a Robert Goddard style motor mount be used for powered landing of SLS solid boosters?
The thought of pairing SLS solid boosters on just about anything one wants into orbit led to the thought of recovering them on barges at sea.
We all remember Robert Goddard's top mounted rocket engine ...
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The costs of a single SLS solid fuel rocket booster
Why didn’t Nasa cluster four solid fuel shuttle boosters around an Atlas V booster. The thrust would be substantially more than that of the SLS, with no fueling problem on the launch pad. It would be ...
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Could Spin Solve Needs for a Hot Water / Steam Rocket?
Instead of the old concept of nuclear thermal steam rocket, could we use spin in a pill shaped rocket to provide structural integrity, flight stability, energy storage, artificial gravity, and ...
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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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What is the difference between a spin up test and a spin prime test?
What is the difference between a spin up test and a spin prime test? And if there is no difference, why not just use the first of those two terms, it being more descriptive?
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How did Space Shuttles get off the NASA Crawler?
The crawler is what transports Shuttles and rockets from the rocket assembly building to launch pad.
When the crawler reaches the launch pad, how is the Shuttle transferred from the crawler to the pad?...
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Can the Virgin Galactic's feathered rentry system be used for first stage recovery?
The stage seperation for Falcon 9's heaviest launch on 28 August 2022 was at approx 75km altitude and at a speed of 8000km/h.
Virgin Galactic's Spaceship two has a max speed of 4000km/h and a max ...
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Why don't we know exactly where the Chinese rocket will fall?
China has launched another Long March 5B rocket that seems liable to fall anywhere
Although the overall risk of harm to people is low—there is only a 0.5 percent chance of injury or death to a human, ...
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Comparing Newtons 2nd law and Tsiolkovskys
I've been attempting to simulate a rocket launch, using:
ΣF= ma + md/dt*v
If ΣF is simplified to only include F_m, being the rocket's thrust, the equation, if solved for a, is:
a = (F_m - md/dt*v)/...
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How fast can a rocket with constant thrust but changing mass travel a linear distance with limited delta V?
Background
I am developing a game / simulation that has spacecraft with advanced albeit at least not physically impossible drives travelling in the solar system. As operation time should be far more ...
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What is the propellant tank weight or weight ratio on dry weight of liquid propellant rocket engine?
I need propellant tank ( or oxidizer tank)'s dry weight- without propellant and engine mass. For example ARES-V's dry mass at earth departure stage is 21,795 kg, What percent of this is tanks' dry ...
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Why was the Saturn V several times as expensive as falcon heavy despite only having twice its payload?
Saturn V could lift 140 tons to low earth orbit, Falcon Heavy can lift 64 (expendable configuration). But Saturn V cost several times more per launch. Why?
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Preventing backfire in rocket engines [duplicate]
In a rocket engine - specifically the SOLID FUEL ones, the "combustion chamber" burns the propellant, creates hot exhaust gases, which pass through the diverging nozzle and create thrust. In ...
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Why do we launch similar payloads on different models of rocket?
Why don’t we just use one launch vehicle to carry different payloads? For example, to launch payloads in the size range of supplies for a Martian base or something made to destroy a Dimorphos size ...
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Orange lines coming from rocket engine nozzle?
This image of a test-fire of the RS-88 ethanol/LOX engine from Wikipedia. It is apparent that there are these orange lines extending from inside the nozzle into the plume. What is it, and why is this ...
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Have there been any rockets whose payload fairings consisted of more than two parts?
Most cargo rockets, such as Falcon 9, Delta IV, and many others, incorporate payload fairings to protect payloads from aero forces and heating during ascent. All of these rockets' fairings split in ...
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How do different stages attach to each other?
I started learning about rockets recently, and while searching for information, I found some ways that different stages separate, but I wandered if it was possible that they could reattach to a ...
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Developing intuition about altitude and velocity in multi stage rockets
I just started learning some basics of rocketry and am struggling to understand the outcomes of a simulator I’m programming. All other things being equal, when I attempt to simulate the altitude over ...
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Actuator bandwidth [closed]
What is the relationship between the slew rate of the linear actuator and bandwidth? What should be the slew rate if I want 5 Hz actuator bandwidth?
For more details:-
I'm using a 2nd transfer ...
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Which orbital class rocket has highest TWR at liftoff?
Which orbital class rocket (active or retired) has the highest thrust to weight ratio at liftoff?
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How Spacex's Raptor Rocket Engine starts?
How does the Spacex Raptor rocket engine start? What are the different stages of startup?
Is the propellant pressure in the tanks sufficient to drive the turbopumps and ignite the preburners and then ...
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Which regulatory agency (if any) is in charge of investigating civilian rocket anomalies?
Yesterday Blue Origin's New Shephard had an anomaly during launch. Happens around 1:22:58 in this video
The accident happened around 29,000ft and the capsule fired its ...
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Would ejecting propellant close to light speed result a '"dream engine"?
"Dream engine" I assume as pictured in the old science fiction: a single stage rocket that can take off from the Earth and then freely travel at least over Solar system, landing multiple ...
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What is the exhaust temperature of a liquid oxygen + liquid hydrogen vacuum engine?
Ideally the exhaust of stochiometric liquid oxygen + liquid hydrogen rocket would be fast moving chunks of ice at zero kelvin. In this way all the potential chemical energy in the fuel/oxidizer is ...
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Resources for Rocket Propulsion
I am a Mechanical Engineering student who is very much interested in Rocket propulsion. Lately I have been searching for good resources to learn concepts about rocket propulsion. I'd be glad to get ...
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What color would the exhaust of an antimatter rocket be?
For the purpose of this question assume that the problems associated with antimatter drives have been solved.
Let's say my spaceship is using a Matter-Antimatter rocket that reacts Antihydrogen with ...
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Question Deriving Mass Flow Rates for an Engine
I am trying to follow the calculations made in this blog post for a $50$ lbf. IPA/Nitrous Oxide engine, but cannot seem to get the values the author made for their propellant flow rates. Since the ...
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Are the Raptor engines too numerous and close together on Booster 7?
SpaceX is in the process of scaling up their highly successful re-usable Falcon first stage to a much larger version with more powerful engines for their Starship program.
These new Raptor engines ...
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What is the likelihood of being able to see the Artemis exhaust plume from St. Augustine Beach, Florida?
Artemis 1 moon mission set for launch: What you need to know
A two-hour launch window begins on Monday at 8:33 a.m. ET, meaning the launch could take place anytime over the ensuing two-hour period.
I ...
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Solar powered spacecraft electrolyzing water as it goes; would ion drives or burning the H +O be more efficient?
I keep trying to think of ways that future asteroid mining might be facilitated, with cost effective in space transport a major challenge; I have been wondering about different ways that a spacecraft ...
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Temperature distribution of air around a rocket
I am doing some simulations in ANSYS Fluent of a rocket traveling at speed of 100 m/s at an altitude of 12000 m where the surroundings temperature is 216.7 K. The image above is the temperature ...
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What is the maximum weight a raptor 2 engine can lift up at sea level on earth?
Regardless of target orbit, how can I calculate the maximum weight one engine can lift?
If the raptor's TWR is 140 and its Thrust is 1.81 MN then:
W = F / TWR = 12,900 N ==> m = W / g = 1.3 tons
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What is the best chemical rocket fuel from a purely specific impulse standpoint?
A variety of different rocket programs use a variety of different fuel types. Researching this, the main fuel combinations I saw were: RP-1 / LOX (SpaceX's Falcon rockets, early stage Atlas and Saturn ...
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Does the debris from the re-entry of Long March core stage ever reach the surface?
It's common for SpaceX to de-orbit the second stage over the ocean (since they still have fuel for controlled re-entry,) but for the Long March core stage that is not the case.
Meteorites have hit the ...
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Is it possible to turn rockets without fuel just like in KSP
When playing KSP if you click a Key (A,S,D,W) then the rocket turns without using fuel. I thought that a rocket needed RCS to turn. Is it even possible to turn a rocket in space without using any fuel?...
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Does NASA have any rocket options to replace ISS segments?
Roscosmos has announced their ISS partnership will end in 2 years
This might have been seen as an indication that the new administration at Roscosmos was in a more cooperative mood. Any such hopes ...
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Selecting an optimal Isp / what makes an Isp too high (mostly for high Isp)
When, and why, is it possible to have an Isp (usually of an ion or nuclear engine with Isp far beyond the limits of chemical fuel) that's too high? What makes the Isp too high, and (other things being ...
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Restartable Solid Rocket Motors Through Expanding Throats?
I recall seeing diagrams on a solid rocket motor that could "blow" itself out through suddenly expanding its nozzle, leading to the propellant no long burning or producing any thrust.
First ...
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What is a rocket engine spin up test?
Recently I came across internet about SpaceX's Booster 7 explosion in a ball of fire during an engine spin up test. I searched Google about rocket engine spin up test but I got no hit. What is a ...
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