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53

A brand new rocket to be launched will have to be assembled, and that's a long process, though I do not know how long. But if it's for an emergency, you may find ready rockets. After the Columbia disaster, space shuttle missions all had a contingency mission in case they found issues with the orbiter before reentry. The planning and training processes ...


44

Aside from thrust/weight ratio, I suspect at least part of this conditioning came from a peculiarity with the Space Shuttle and its launch process. The Space Shuttle's launch process was different because it had two different types of engines firing at launch. Its liquid-fueled main engines (mounted on the back of the orbiter itself) were ignited several ...


36

Sea Dragon The very large rocket was probably Sea dragon and the advantages were more on allowing a massive vehicle to be built at all rather than inherent advantages in starting underwater. (image credits) Building the launch vehicle on a slip way and floating it to the launch site bypasses a number of size constraints in building and moving large ...


35

TL;DR: it is inefficient. You should play some Kerbal Space Program and see for yourself the effects of travel in this way. Assuming, of course, you didn't really want to enter the orbit, but wanted to e.g. go to the Moon or deep space probing. Especially in conjunction with Wikipedia's note about not having to attain escape velocity to leave gravity well....


35

I've done a very quick and dirty guess by pulling out all the dates of "things that look like orbital launches" from the JSR dataset, and looking for clusters of dates. I have omitted launch failures and suborbital launches, and converted everything into calendar days. It also omits everything before 1963 (which are recorded differently) but I ...


30

The high-gain antenna deployment failure that caused Galileo to only be able to return data at a tiny fraction of the design rate was caused by vibration resulting from its being shipped cross-country by truck. In December 1985, the antenna, again in its own shipping container, was sent by truck to NASA's Kennedy Space Center (KSC) in Florida to await ...


28

Here ya go! It includes some other views, but does have the dashcam. As usual though you can't really see the stars. Shuttle mission STS-133


28

What about their design seems to make them inflate and blow off? Did they have some sort of air scoop built in? The final version did (history below). They were made of Tyvek and had a pocket/parachute built in. I can't find a great picture but this at least shows the parachute. If they didn't blow off what would the consequences be? If they ...


24

What you're describing is (more or less) the StarTram "gen 1" design. The reference design has: 40 tonne unmanned cargo projectile, 25 tonnes of payload, ~2 m wide, ~13 m long. A 130 km maglev acceleration tunnel, evacuated. An exit point 6000 m up, on a mountain. A plasma window to allow projectile egress into atmosphere without repressurising the entire ...


22

One reason large rockets are launched directly up is structural. Cylinders are strong under compression, stacking cylinders on top of each other means the weight is symmetric, you need less structural weight to hold it all up. Launch it straight up and make gentle changes in direction and the forces are equally distributed through the structure all the way ...


22

What you are seeing is a consequence of Thrust to Weight ratio at t=0. If the vehicle weighs say 6.5 million lbs (Saturn V example) and has a thrust of 7.9 million lbs, then it has about a thrust to weight of about 1.2, so that will be kind of slow but every moment after 0, the fuel is burned off mighty fast, and the stack gets lighter, but the thrust stays ...


20

The center of the Earth is, for any reasonable approximation, in one of the focus points of an elliptical orbit. For a circular orbit, there is only one focus point, so the center of the Earth is in the center of the orbit. The plane of the orbit thus would intersect both the center of the Earth as well as the launching site. If the launch site was on the ...


20

In late 2010, a Soyuz spacecraft was damaged in transit Earlier report on the incident: Engineers spotted damage to the Soyuz TMA-20's transport container after it was shipped by rail to the Baikonur cosmodrome in Kazakhstan, the president of the Energiya spaceship factory, Vitaly Lopota, told the Interfax news agency. McCollister's, a company ...


19

Many novel launch schemes need some amount of help from rockets. What kills a lot of them is doing a tradeoff study of just enlarging the rocket part and getting rid of the non-rocket part. Surprisingly often, that works out to be better and cheaper. --Henry Spencer This is a system that needs a rocket part, as one of these two cases would necessary ...


19

Are there any satellites that have been lost or damaged getting to the launch site? Here's one: This incident was the result of trying to move NOAA-N-prime (which would later become NOAA-19) a tiny bit for inspection purposes. See Was the NOAA-N Prime satellite really dropped on the floor? for details.


18

It's a matter of optimal trajectory - pitch maneuver/gravity turn which depends on characteristics of the rocket, the atmosphere, gravity etc. In particular, for rockets with lower initial thrust-to-weight ratio, the trajectory starts almost vertical; "rounding" the angle to perfectly vertical makes the launchpad infrastructure and preparation process easier;...


18

There is a detailed list here of everything that needed to be done for a scrubbed Saturn V launch, which gives an idea of the scale of the problem. Lots and lots of individual tasks to ensure the booster is still safe and stable. Get the crew out and safe everything Drain the propellants from the booster (they usually can't be left fuelled for a prolonged ...


14

The VASMIR 200 is listed as having a thrust of 5.4 newtons, and you need 9.8 newtons to lift 1kg against earth's gravity. So 700 tonnes is going to need more than a million engines and be consuming more than 254 GW of electricity. So even if the engines are weightless this is not lifting off from earth without co-opting the power generation of a sizable ...


13

Image source The booster has two kinds of joints between its segments, field joints and factory joints. The booster parts shipped to KSC were made up of two segments joined by factory joints. At KSC, these parts were put together using the field joints. There are three field joints and seven factory joints in a Shuttle SRB. Image Source Both kinds of ...


13

The short answer is that a spacecraft is attracted to the center point of the earth, not to the earth's rotational axis. [I]t would make sense to me that launching east would result in a 0° inclination with the orbital plane raised so it's parallel to the equator but above or below it. Here's one explanation of why that wouldn't happen that you might ...


12

The ISS does not have emergency's that require a rocket to bring supplies. It can have an urgent need of something. Either everyone stays on the ISS or some/all crew leave. It is downhill all the way to Earth, and the crew can leave anytime. Worst case the crew abandons the ISS and it burns up on re-entry. There are a couple of good answers on this ...


12

In addition to thrust to weight ratio, in simple terms Falcon's engines (Merlin) light much faster than other engines. The space shuttle had SRB that light relatively fast, but the main engines took some time to spool up and get started as well as get calibrated. The SSME would start lighting well before T=0 for two reasons, the first because of this start ...


11

'Loaded' means it's loaded with propellant (as opposed to something like 'inert' or no marking at all, for casings that have not been loaded). It's used to make it easy to distinguish which casing segments have been loaded with propellant and which ones haven't. Loaded segments require different handling procedures than non-loaded segments. In the military,...


11

A satellite with SNAP-9A plutonium energy unit was launched from Florida in 1964. It failed to reach orbit. Debris fell in Southern hemisphere including Madagascar. It's more than 14000 km fom the launch site. https://en.m.wikipedia.org/wiki/Systems_for_Nuclear_Auxiliary_Power


11

Calculating how much LOX is lost is going to be an interesting calculation, but I'm not sure we have the data for that. Instead, I'll be focussing on the other part of your question: Is the loss replaced by tanker trucks or by a liquid oxygen plant near the launch site? The ball-shaped structures near pad 39A are storage tanks for liquid propellants. It'...


11

What was the duration of the launch window this day? According to Spacelaunchnow, the daily launch window was instantaneous, but there were daily opportunities from July 15 to August 12. Did it first enter a short period of LEO for phasing and/or staging, or did it launch directly into its interplanetary trajectory? From the timeline, it appears that it ...


10

Let's refine your calculations a bit. Worldwide, less than 200 rockets are launched each year. They have an average empty weight of 30 tons (rounding up a bit), which is mostly aluminium. That adds up to 6000 tons. This is a tiny fraction (0.001%) of total aluminium production (60 million tons). if it were economically feasible to recover rocket stages ...


10

It's all covered by a payload fairing that isn't flush with the body of the spacecraft. A picture is worth a thousand words:


10

The MAKS design was supposed to do this. There is much additional info about MAKS in the answers to this question and their sources: Seeking concept art or photo of MAKS on carrier plane


10

Your question is, as I understand it, pointing out that there are two ways to get from the surface of the Earth to the surface of the Moon. Way one: Burn upwards until through the thickest part of the atmosphere to avoid aero drag. Burn sideways to attain orbital velocity and raise apogee and perigee into space. From Earth orbit, burn prograde to attain ...


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