Questions tagged [launch-vehicle]
Questions about a craft used to propel payloads into space, usually a rocket-powered vehicle
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Can a lighter rocket lift more than a heavier rocket?
Let us consider two launch vehicles - "A" and "B". If "A" has a larger wet mass than "B", does this imply "A" has a higher payload capacity to a particular orbit, from a particular launch site than "B"...
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Are solid-fueled launch vehicles faster to orbit than liquid-fueled ones?
The (relatively) new Kuaizhou family of launch vehicles is described as "quick-reaction", and is based on ASAT and ICBM heritage.
Solid-fueled rockets have been, historically, cheaper to launch on, ...
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Why do we need dedicated launch vehicles for small satellites?
The Wikipedia webpage on Small-lift launch vehicle gives a huge list of dedicated launch vehicles with a maximum payload capacity of 2,000 kg (4,400 lb) for small satellites, which are either retired,...
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1answer
196 views
Why doesn't Ariane-5 lift off at T=0 seconds?
I have seen Ariane-5 lift off at T+07 seconds and not at (or close to) T=00 seconds. The following statement is from the Ariane-5 User's Manual (Page 35, Section 2.3 - Typical Mission Profile):
The ...
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2answers
505 views
How many space launch vehicles are under development worldwide?
I need to know how many space launch vehicles (across categories - small, medium , heavy etc) are under development, worldwide.
For instance this report talks only about the number of Small Space ...
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If a comet-sniffing spacecraft were launched today, could it catch up to newly-discovered ε>3 C/2019 Q4 (Borisov)?
As found in this answer to What makes scientists already so certain that Comet C/2019 Q4 (Borisov) is a comet and not an asteroid? the orbital parameters of this eccentricity > 3 visitor to our solar ...
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1answer
88 views
What is “additional line load” [N/mm] for the Ariane 5 launch vehicle?
In the textbook Spacecraft Systems Engineering 4th ed. page 14, table 2.1 ("Acceleration values for the Ariane 5 launch vehicle") provides data on the loading of the Ariane 5 spacecraft. One of the ...
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3answers
431 views
Why don't launcher rockets ordinarily have names?
There are names for the class or family of launcher, e.g. Delta IV, Electron, Falcon.
Sometimes the launcher is "named" for a specific configuration of a class, e.g. "Delta IV Medium+ (4,2)", "Chang ...
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Launch vehicle trajectory tool for ascent phase to orbit using PYTHON
Currently, I am developing a trajectory optimization tool for launch vehicle from lift-off to orbit using python for my project. Since I'm new to optimization problem, I am finding it hard to ...
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If there “won't be” rockets to launch individual cubesats, then why did JAXA build exactly that? (SS-520-xx)
The question Why isn't there a rocket to launch a single cubesat? has several good answers that explain why there isn't and/or will not likely be one, based mostly on commercial viability, consistent ...
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Is the space shuttle the only launcher that jettisson tank without any engines in its staging process?
All launcher I know jettison stages composed of both tank and engines. I do understand that:
the jettison process is useful to get rid of dead weight
jettison engines allows the use of more suited ...
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187 views
Why aren’t rocket stages modular and interchangeable?
Being an avid player of Kerbal Space Program, it is intensely frustrating to return to the real world and have to remind myself that rocket stages can’t generally be swapped out between rockets (...
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260 views
Why was the Energia’s payload capacity to lunar orbit greater than its payload capacity to geosynchronous orbit?
The Energia rocket, developed in the 1970s and 1980s to launch the Soviet Buran space shuttle, had the second-highest payload capacity (100 tonnes to LEO) of any rocket ever flown (and the highest-...
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191 views
How often did launch vehicles have a “Stage 0”, and what does it mean exactly?
While trying to do some reading for the question Need help understanding staging shown in infographic of Titan launch of Hexagon satellites I ran across the Wikipedia article for Titan III.
This ...
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1answer
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Need help understanding staging shown in infographic of Titan launch of Hexagon satellites
The NPR News item I Spy, Via Spy Satellite: Melting Himalayan Glaciers discusses use of declassified historical satellite images that include glaciers, and link to the newly published and Open Access ...
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Why does the Falcon 9 launch heavier payload in LEO than Ariane V and the other way around for GTO?
Browsing a comparison of orbital launch systems on wikipedia, I notice that launcher capable of launching payload in GTO can launch in GTO approximately all the mass of the payload they can launch in ...
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GLOM of a launch vehicle
What do you mean by GLOM of a launch vehicle? When I googled about it, it says it is a type of mass but I am unclear about it.
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History of multiple-payload launches?
Another question asks why Spirit and Opportunity weren't launched together. My gut response was that multiple-payload launches were less common then than they are today, but I don't actually know if ...
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How common are “parallel stages” in a launch vehicle?
I'm being told in this answer and in this comment that the fourth stage of the Farside rocketoon lies in the center of the four "cores" of the third stage.
See this answer for several pictures of ...
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Was there any period of time when other U.S. launchers were abandoned in favor of the Shuttle?
The comments to this recent question disagree on whether the U.S. briefly abandoned other launch systems in favor of the Space Shuttle.
The Shuttle was designed to be capable of bringing all U.S. ...
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Laser powered LEO launch system
Latest research on beam powered propulsion seem to focus on the microwave spectrum as it is easy to catch by the orbital vehicle. However I argue it could be way cheaper to use a solar powered laser ...
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1answer
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What does the core stage of a launch vehicle mean?
I have seen the use of the term 'core stage' in the context of space launch vehicles. I am not able to clearly understand what it exactly means? I have learnt about launch vehicles having multiple ...
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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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1answer
232 views
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
569 views
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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1answer
304 views
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
101 views
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
151 views
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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112 views
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
89 views
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
223 views
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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1answer
244 views
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
193 views
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
470 views
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
723 views
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 ...
