Questions tagged [launch-vehicle]
Questions about a craft used to propel payloads into space, usually a rocket-powered vehicle
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Payload fairing separation- Event based or time based?
Refer the answer for this question How strong and "hot" is the wind on the payload after the fairing is deployed at ~110km?
It is clear that the fairings are separated when the free ...
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New Terran 1 rocket - launch costs for Cubesat
I was reading about the Terran 1 rocket and the fact that the founding company managed to secure the launch site at Cape Canaveral. Pretty amazing story on its own but then I looked at prices and they ...
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1answer
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What licenses do you need to launch a rocket and put something into orbit? [duplicate]
Do you need a licence to build, and fly a rocket (mainly flying)? Can you build any type of rocket and fly it anywhere at any time?
Are there regulations on what you can take to space?
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Why did the S5.2/9D21 rocket engine engine have pyrocharges?
In a recent question, an answer showed a diagram of a Soviet S5.2/9D21 rocket engine. According to the diagram, there are four pyrocharges (3, 7, 24, and 27) in the engine. What is the purpose/...
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Why was the engine of the launch vehicle recently tested in Iran “not a very good missile engine”?
The NPR News item What's Iran Up To With Recent Rocket Launch Attempt? by NPR's Geoff Brumfiel, about a recent launch test in Iran includes the following:
Earlier this week, Iran attempted to ...
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Why is SpaceX not creating its own launch vehicle for small satellites?
With a (predicted) $5.5 Billion dollar market, why isn't SpaceX trying to build its own 'mini launch vehicles'? With the brand and the technology they have, they can easily capture a huge chunk of the ...
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What are “high altitude winds” and why do they often delay rocket launches?
High altitude winds seem to frequently postpone launches from Earth to orbit. Presumably, they are fast and strong enough to induce stresses on a rocket or impede guidance, but that's guessing from ...
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Why are the blueprints of old satellites still not available to public?
There are old, now mostly useless blueprints of old satellites, (or rockets, or pieces of software, or engineer's notes, e.t.c) but they are still closed to public. Why? Can it harm the Space Agency ...
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Proton K or M altitude at Max-Q
I'm trying to fill out a sketch table as part of a research project, and I've run into a bit of a snag. Hopefully someone here can help me out.
I'd like to know the altitude of the Proton K or M ...
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1answer
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Loading the LOX into Falcon 9 V1.1 and Falcon 9 Full Thrust
It is clear from the spaceflight101.com that there is difference in Launch sequences of Falcon 9 FT and Falcon 9 V1.1.
Clearly, Spacex has found a way to load the tank in 30 minutes (falcon 9 FT) as ...
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1answer
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At which stage of rocket development does systems engineering become critical/useful? [closed]
Rockets are complicated system and the interaction of the sub-systems are even more complicated.
But different subsystems tend to be developed parallels without much interaction but does so when ...
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How is thrust transmitted from strap on boosters to the central core?
Strap on boosters of a lot of heavy launch vehicles seems to be attached with just a few "flimsy" struts.
Here are few images for reference :
Some of the possibilities:
These support structures ...
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1answer
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What are the small red cylinders used for on the bottom of the Soyuz Launch vehicle?
They are fitted on each of the first stage strap on boosters and on the second stage core and are all orientated the same way. Pipes and cables connect to the stages from the cylinders. I believe they ...
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1answer
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Quantitative benefits of Atlas II's engine-dropping or 1.5 staging?
The question Would there be any advantages for a rocket with two “half stages”?
begins with:
A "half stage" is a rocket stage which separates with its engines, but not fuel tanks. Common examples ...
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Who owns the IP developed in the VentureStar program?
The VentureStar program including the prototype X-33 cost upwards of $1 billion, surely some of that went into still meaningful intellectual property. Who would own it now? NASA provided the funding, ...
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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 ...
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Has the use of any commercial launch vehicle's engines on an unrelated vehicle ever been seriously considered?
When reading On the Cusp: What’s NextDARPA Perspective on Space Briefing prepared for 53rd Robert H. Goddard Memorial Symposium
March 12, 2015 I saw the slide shown below. The slide's heading is ...
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2answers
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Can a rocket be intercepted in mid air?
Suppose that:
1-an interplanetary crewed rocket such as SpaceX BFR is built in secret.
2-the launch station can be arbitrary located.
3-the rocket is launched without any warning.
4-the rocket is ...
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1answer
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Should all the Air-Launch systems be deployed at sub-sonic speeds?
There have been several proposals to develop Air-Launched rockets, like what Virgin Orbit or Pegasus rocket doing.
All of the concepts are released from aircrafts in a Sub-Sonic velocity (0.7 to 0.8 ...
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1answer
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Center of gravity calculation for any rocket or launch vehicle
I understand that the the center of gravity can be calculated by making a 3D model of the rocket or launch vehicle when it is completely filled and stationary.
But in case of continuous ascent (i.e. ...
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Have there been any other cheap, modular launcher designs like the OTRAG?
The OTRAG rocket is an interesting design. Vehicles would be assembled from 4 to hundreds of identical rocket modules. By using an extremely simple design, producing the modules cheaply using ...
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Will Japan's Interstellar Technologies really call its rocket a “Zero”?
The Space News article Japan’s Interstellar Technologies goes full throttle toward small orbital rocket says:
LOGAN, Utah — Japanese startup Interstellar Technologies is developing the main engine ...
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1answer
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How can a rocket go straight up after ignition? [duplicate]
We have seen during rocket launches that the rocket goes straight up after the launch clamps have disconnected.
What ensures that it doesn't tilt because of the uneven mass distribution?
How does a ...
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1answer
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Has an object ever been put in orbit where the first stage was always at maximum thrust?
Variable thrust through changing the number of engines burning, or through propellant throttling, or other means is often/usually done to reduce maximum aerodynamic stresses on the rocket as well as ...
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Do launchers using only solid propellant exist?
The question is restricted to launchers that have already been used to launch an object into orbit before today (April 2018).
Some military ballistic missiles run only on solid propergol (e.g. the ...
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1answer
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Why is ISRO's PSLV named “Polar”? Are there challenges for other inclinations?
The "P" in ISRO's PSLV stands for "Polar".
Is there anything particularly "polar" about this launch vehicle, or is the use of the word in the name of the rocket more historical or for marketing ...
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1answer
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What are the falling parts in this ISRO rocket launch?
ISRO launched IRNSS-1I satellite yesterday using its versatile PSLV-XL.
In the launch video (from 00:35 to 00:40), within five seconds of the launch, many large parts of the rocket are seen to be ...
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Pressure inside a launch fairing - falcon 9
This article indicates that a faclon 9 launch is being delayed due to an issue with the "payload fairing pressurization system".
Are launch fairings pressurized to 1 atmosphere for the benefit of the ...
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1answer
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What single figure best compares the mass launch capacities of different rockets?
How much kinetic energy does a given launch give its payload?
Could all launches be fairly lined up according to one single scalar representing how much kinetic energy they have actually delivered to ...
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1answer
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How does horizontal payload mounting influence satellite design
Payloads have to withstand forces of several G, but those forces point backwards toward the rocket engines (or close to). Also, while the launcher is in the pad the satellite is subject to 1G, but ...
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1answer
371 views
Why Has Research Moved Away from SSTO Launch Systems? [closed]
I remember in the late 90's and early 00's it seemed like SSTO launch vehicles were all the rage and they were even building the X-33, then suddenly nobody wanted to talk about SSTO vehicles anymore. ...
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Was Sea Dragon second stage reusability ever plausible?
Many websites consistently claim that the first stage of the enormous Sea Dragon rocket was intended to be reusable. While recovering a giant booster from sea after a splashdown may seem tricky, it ...
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Implementing control system to track position and velocity references simultaneously
I've been trying to implement a PI (proportional-integral) controller to allow a launch vehicle to track 2 reference states simultaneous, namely position and velocity, so that the launch vehicle will ...
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1answer
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To what extent, if any, does the exterior paint color of a launch vehicle affect its propellant & vehicle thermal management?
Many orbital launch vehicles use a combination of a chilled oxidiser (usually LOX when dealing with liquid-fuelled rockets) and a fuel (commonly RP-1, but with many designs now opting for Methane). ...
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What is the smallest launch vehicle that has put a satellite in a geostationary orbit?
Minotaur V might become a candidate for the smallest current launcher to put a payload in GEO, but it has only launched LADEE yet. The first satellite in GEO seems to have been Syncom 1 which launched ...
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How long does the upper stage stay in orbit if the payload is released on GTO?
A launcher upper stage may not stay in orbit for long, as it does not need to go as high as the payload and thus travel at an altitude at which although it is thin, the atmosphere is still dense ...
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Fuel-optimal thrust profile for an orbital ascent on a planet with an atmosphere
This is a continuation of a previous question posted a few months ago. If we consider a SSTO vehicle launching from a planet with an atmosphere, would it be fuel optimal to have a period of lowered ...
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What uncrewed interplanetary exploration probes have launched on heavy/superheavy-lift vehicles?
What uncrewed interplanetary probes have launched on heavy/superheavy-lift rockets? I'm using NASA's definitions of heavy and super-heavy vehicles; heavy-lift is 20-50 metric tons to LEO, super-heavy ...
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How can the same upper stage be optimal on a common core booster as well as on a single booster?
Bundling three or five first stage cores together improves the launch capacity a great deal. But Delta, Falcon and Angara are supposed to use the same upper stage in their multiple common core ...
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How large could launchers become?
I've heard that the size of Saturn V was pretty much as big as could've been built in the 1960s. And the Soviet N1 did basically fail because it was too large for their infrastructure and engine size ...
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What does determine when a rocket goes from a vertical trajectory to an horizontal one?
Rockets are launched vertically and then turn to have an horizontal course. It sems logical to begin vertically to reach less denser atmosphere quickly and to travel horizontally when reaching low ...
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Using large orbital launchers as sounding rockets. What are the opportunities and challenges?
Instead of launching a payload to orbit, consider one of the big launchers of today (like Atlas V, Ariane 5, Falcon 9, Proton) being used as a sounding rocket for astronomical observation purposes. ...
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What does it take to make a spacecraft able to launch on any out of several different launcher types?
Choice of launcher seems to be an early decision in the design of spacecrafts. There would be an advantage to having the option to easily change launcher, especially for an interplanetary mission with ...
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Some examples of pressure fed engines used on launch vehicles
Are there any examples of pressure fed engines used on launch vehicles? I already know of the ones on the wikipedia page which include
Firefly Space Systems
OTRAG (rocket)
Quad (rocket) of Armadillo ...
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1answer
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Is the Towed Glider Air-Launch System's glider now also a rocket?
In an answer to a previous question, I learned about the game-changing nature of Towed Glider Air-Launch System technology.
While the glider in the Towed Glider Air-Launch System (here, here, and ...
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What is the game that the Towed Glider Air-Launch System (actually) changes?
I understand that the Space Technology Mission Directorate's Game Changing Development program https://gameon.nasa.gov/ has a broad scope and is not necessarily focused on immediate payoff. ...
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How would a bulk payload like fuel (instead of delicate technology) change boost to LEO optimization?
This answer suggests that if a payload were simply bulk propellant, such as LH2 and LOX, and not delicate technology such as an interplanetary probe or communications satellite, then there may be some ...
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What factors prohibit building a space cannon to launch raw materials? [duplicate]
I am envisioning a magnetic cannon to launch materials directly from Earth's surface to geosynchronous equatorial orbit. The parameters I have in mind are a near vacuum launch tube, about 10 km in ...
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With 31/32 successful launches why isn't the Delta IV a category 3 certified launch vehicle
I'm having some trouble understanding the requirements for launch vehicle certification. According to NPD 8610.7D the requirements for a category three LV are "a demonstrated flight record of a ...
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What does it mean for a launcher to be 'nuclear-certified'?
This article says NASA has booked a nuclear-certified Atlas 5 for the launch of the Mars 2020 rover, and says this:
currently, Atlas 5 is the only launch vehicle that holds a NASA
certification ...
