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Questions tagged [launch]

Questions regarding the takeoff or the liftoff phase of the flight of a rocket and the set of activities required for preparation of the launch vehicle leading to it.

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1answer
605 views

Falcon Heavy path and propulsion to Mars

Has SpaceX provided any details on their specific plans for the trajectory of the Falcon Heavy payload propulsion on its trip out as far as Mars orbit? I'm wondering if they have made public whether ...
4
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1answer
373 views

Can the launch of Falcon Heavy be seen well from the Rocket Garden?

Is any viewing of the falcon heavy launch visible from the $75 rocket garden ticket? Just trying to decide if it would be worth the money.
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3answers
454 views

Soyuz has a Space Periscope?

The image Photo ID: ISS049-E-003166 can be found in Flikr and Wikimedia Commons as well as in Spaceflight Now. There is a long (perhaps 1 meter?) green structure that is sticking out from the side of ...
8
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1answer
1k views

How far around the world does a rocket travel before it enters orbit?

If a rocket launches from Florida, how far around the world does it travel before it reaches orbit? Is it in space before it completes crossing the Atlantic? Does it vary for different powered ...
6
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1answer
141 views

How was it difficult for the PSLV to launch a record of 104 satellites?

Last year, ISRO launched 104 satellites successfully into orbit. People praised it as an 'astounding achievement'. Besides a more complicated-than-usual satellite separation, what truly was ...
9
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2answers
288 views

Do smaller rockets require better weather at launch than larger ones?

The Spaceflight Now article Rocket Lab test launch halted by ship traffic, deteriorating weather mentions that the recent planned launch of the Electron rocket was cancelled due to a combination of ...
4
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1answer
110 views

Can a launch vehicle put several different satellites into different RAAN in one launch?

I am trying to see how frequently I can acquire a link for 1,2,3,4,5 or more satellites. When I began, I just decided to separate satellites by True anomoly, because that made the most sense. But now ...
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4answers
625 views

Has anyone considered using multiple rockets to lift a single payload?

I mean something like Kerbal Space Program style - payload between 2 parallel rockets e.g. Also, space shuttle configuration comes to mind where we have the large fuel tank between 2 solid boosters: ...
5
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1answer
617 views

Would a hex-cluster of SpaceX boosters around a central booster lift a large payload into space?

I'm sure it's possible, but would it be wise to place a hex-cluster of SpaceX boosters around a central booster to get a very large payload, or one going to a very high orbit, into space? Maybe even ...
4
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1answer
363 views

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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2answers
526 views

Reasons why the Lunar Rover DID NOT become “a jumble of loosely assembled broken parts on Launch”?

A number of comments and some answers at the question Can I drive Elon Musk's Tesla in 100 Years? suggets the Tesla Roadster "would not survive launch... it would be a jumble of loosely assembled ...
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0answers
218 views

Launchpad platform structural design

I am a civil engineer and would like to do a study on the design and construction of launching platforms for large lift vehicles, one example of which is the ELA 3 (Ariane Launch Area 3) in French ...
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2answers
2k views

What are these yellow devices attached to the Falcon Heavy?

I was looking at the pictures of the newly rolled out Falcon Heavy and I noticed these odd yellow extensions on the payload faring. What are they?
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2answers
747 views

What secondary payloads, if any, are launching on the inaugural fight of Falcon Heavy?

Overshadowed by a silly, yet awesome primary payload — 'a cool colored cool electric sports car playing a cool track' on to a heliocentric orbit, are there other satellites/secondary payload Falcon ...
19
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1answer
3k views

Why are Falcon 9 main engines throttled down and up shortly after launch?

On the official webcast of SpaceX's Iridium-4 mission a "throttle down and throttle back up of the Falcon 9 first stage engines" is mentioned. Why would one throttle down at a crucial time during ...
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3answers
6k views

Why are the Falcon Heavy boosters stacked in a row instead of a triangle?

I wonder if triangle stack would be a better design to handle thrust and stability of the flight. Photo source (public domain).
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0answers
69 views

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
114 views

Retractable delta wing rocket [closed]

I always wondered: would a 10,000 lb, 40 feet small rocket with retractable delta wings winched from a cargo plane,propelled by a jet similar to a f22 to mach 3 before igniting its own rocket My ...
8
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1answer
890 views

What if an engine fails to ignite on Falcon Heavy?

The Falcon Heavy has 27 engines (Suck on it N-1!) in three sets of 9 (per core booster). SpaceX initially suggested they might need a couple of static fires to nail down the ignition sequence, since ...
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0answers
45 views

Where can i book a flight for scientific experiment to 100 km high? [closed]

I have just been wondering if is there any company in Europe which launch scientific experiments into an altitude of about 100 km?
4
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1answer
105 views

Why is LC39A's TEL enclosed, but the newer SLC40 TEL is not?

After the AMOS-6 explosion on the pad at SLC-40 in September 2015, SpaceX spent a lot of time rebuilding SLC-40, including a very big update on the TEL (Transporter/Erector/Launcher). Whenever they ...
4
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2answers
262 views

Calculating Apollo launch azimuth

The launch azimuth for Apollo missions to the general area of the lunar equator was approximately 70 degrees. Could someone explain in simple terms how this figure is arrived at? I presume that if ...
5
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2answers
215 views

What is the best position for a human to be in during launch?

We know from the answers to the question If a human is being sent to space in a rocket, does the seating angle matter? that seating position at launch is of less concern than landing. We also learn ...
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2answers
411 views

What kind of payload is Mission 1390 (Zuma) going to launch?

Usually, when there is a "classified" payload, there are hints as to what it would be. Why is it different on this mission? Why is no government entity taking credit for it?
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1answer
335 views

Saturn launch precautions for clearing tower?

In watching some Saturn rocket launches from the perspective of the camera being on the launch tower, it seems as if there was relatively little distance between the launching rocket and the tower. I ...
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2answers
3k views

How many rockets have been launched into space? (roughly, of course)

First I was going to ask how many rocket bodies lay at the bottom of the ocean, but I simplified further. Remember, this includes sounding rockets; anything passing the Kármán line. I'm looking for ...
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6answers
5k views

Would launching a shuttle from a 45 degree angle be the most fuel efficient for a rail gun?

So I am in fourth year and doing the BT Young Scientist (Ireland’s version for a science fair but bigger and there is a cash prize) and came up with the idea to launch a space shuttle from a rail gun, ...
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1answer
246 views

What does “That's how we drive to 48!” mean?

The video in this 27-Oct-2017 45th Space Wing tweet uses the phrase "That's how we drive to 48!" What does it mean? T-3 days: Our 45 Operations Group is ready to take on this Epic Launch from the ...
5
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1answer
310 views

Do Falcon 9 preflight static fire ignitions use up the engines' ignitors?

After a Falcon 9 has its static fire several days prior to the actual launch, are the TEA-TEB ignitors inside the engine replenished? Or do they have enough to ignite the engines for the static fire ...
11
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2answers
361 views

Is there a theoretical limit to the size of launch vehicles?

Is there a limit to the size (mass, structural issues) of boosters that can be launched either to orbital or escape velocity? I am asking about such constraints as the required thrust to weight ratio ...
17
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2answers
1k views

Has SpaceX re-used a first stage twice yet?

SpaceX has re-used a first stage once, several times now. Has it re-used the same first stage twice yet? If not, has a particular mission been named that will be the first second re-use?
8
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1answer
106 views

Are there any events planned to celebrate Sputnik's 60th anniversary today?

April 12 has Yuri's Night to commemorate Yuri Gagarin's first orbital flight by a human. The launch of Sputnik 1, the first satellite humanity put into orbit, on 4 October 1957 at 10:58pm Moscow time ...
2
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1answer
126 views

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 ...
25
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1answer
5k views

Does anyone who works at SpaceX know the paths of classified payloads?

As SpaceX has launched both NROL-76 and OTV-5, does anyone at SpaceX know the trajectory of the vehicle, or is the falcon upper stage under the direct control of the Air Force?
10
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1answer
837 views

Why did Amazonas5 2nd stage ignite before 1st stage separation? [duplicate]

Watching the Amazonas5 launch, and at 1st stage separation, the commentator noted that the 2nd stage would ignite before the separation in order to "maintain constant acceleration." I'm wondering how ...
4
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0answers
749 views

Differential Equations for Rocket Launch in Polar Coordinates

I'm trying to understand the equations of motion for a rocket launched from earth, through the atmosphere, and into LEO. I found a set of ordinary differential equations which describe the motion of ...
3
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2answers
437 views

Why do SpaceX rockets' re-entries seem to burn (as in heat the hull) less than the space shuttle? [duplicate]

Why do SpaceX rockets' re-entries seem to burn (as in heat the hull) less than the space shuttle ? Is it because of less friction surface ? Thanks !
5
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1answer
150 views

SpaceX's ITS as heavy lifter for Earth orbit

Was the booster of the interplanetary transport system ever considered as a super heavy launch vehicle for commercial payloads onto LEO and GEO? (with an expendable or reusable second stage) Or its ...
5
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0answers
254 views

What is the source of the 'whoop' sound made before the liftoff (T-3s) of Atlas-V rocket?

For reference, you can hear the distinct 'whoop' sound at T minus 3 seconds mark of the recent TDRS-M launch. This sound has been distinctive for most previous Atlas-V launches as far as I can ...
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2answers
705 views

What will the Falcon Heavy maiden flight launch as its payload?

I know that Elon Musk has stated that SpaceX will try to launch the "silliest thing imaginable" on the maiden flight of the Falcon Heavy, but will it be a Dragon capsule on top or a special SpaceX ...
14
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1answer
619 views

Why are launch escape towers jettisoned early?

Why are launch escape towers usually jettisoned fairly early in the flight? What if a problem went wrong during an upper stage burn and the escape tower had already been jettisoned? I know that ...
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1answer
382 views

What is the blue box that the Exp. 53 Astronuats/Cosmonauts carried with them?

Looking at a video from Roscosmos on instagram, Exp. 52 Cosmonaut Sergey Ryazansky carried a blue box with him during his walk to the Soyuz rocket. Upon looking at more videos of Astronauts boarding ...
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1answer
2k views

What are the Grid fins on the Soyuz escape system used for?

Why does the crewed version of the Soyuz rocket use grid fins on its launch escape system? It seems like extra weight to carry along during a portion of the flight. Here's a rendering of the upper ...
2
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1answer
369 views

Was the Space Shuttle the most efficient orbital launcher, based on the launch/LEO mass ratio?

It seems that the mass of the Space Shuttle at launch was around 2,000 tons, and it could deliver a total payload of around 122 tons to LEO. This would give it a launch/LEO mass ratio of around 16.4. ...
15
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1answer
324 views

What is Range maintenance?

As discussed in this question, there will be no launches from Cape Canaveral for several weeks during the summer of 2017 because Eastern Range is closed for maintenance. I assume it includes some work ...
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2answers
6k views

Why won't SpaceX launch a rocket for a month?

The last launch of a Falcon 9 (Intelsat 35e) took place on July 5, but the next launch of a falcon 9 (CRS-12) won't take place until August 10. Elon said that SpaceX still had 12 launches to go this ...
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1answer
135 views

Does spacecraft injection point and perigee coincide?

When a SpaceCraft is injected into an orbit( either LEO/GTO ), does the point of injection ...
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2answers
2k views

Space Shuttle “go at throttle up”

On all of the launch videos and recordings for the Space Shuttle, the mention is made from Houston (after getting through Max-Q) of "go at throttle up", indicating that the launch is ok for going back ...
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0answers
135 views

What is the effect of launching from higher altitude on fuel burn and rocket performance? [duplicate]

There are many sites around the world apart from USA, that have such great locations to launch from. Saving hundreds of thousands of dollars in fuel costs. Can someone assist me with a model that ...
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0answers
130 views

Databases of “scrubbed” launch attempts?

I'm curious if there is a statistically demonstrable tendency not to schedule launches on certain days, such as those that contain leap seconds (see answers below this question), year changes, or ...