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17

Definition of terms: A shock wave by itself is not a "sonic boom". A sonic boom is an event, produced by the shock(s) passing over something - an observer, a building, the ground. The "boom" is characterized by a rising/falling/rising pressure disturbance called an "N-wave" because the disturbance has the shape of an N when plotted. A model in a supersonic ...


11

Yes, it produces a sonic boom. But the shockwave travels in the same direction as the rocket (i.e. up) and doesn't reach the ground.


10

The latitude of a launch site determines the minimum inclination that can be directly reached; launching from 28.5º latitude in the due-East direction achieves a 28.5º orbital inclination. Launching to any higher inclination is straightforward, simply by steering continuously North-of-East during the ascent. In the extreme case, if you fly due North, you ...


9

There is likely minimal effect. At rocket speeds, there is very little effect of shear stress, the only significant effect is particles hitting the leading surface of the rocket. Also due to how fast hey are going, the effect of the rocket of "pushing air out of the way" does not have time to get far ahead of the rocket, and this drops further behind as ...


8

It would not be feasible. Compressed-gas thrusters have a very low specific impulse (a measure of fuel efficiency), and the ratio of launch mass to payload mass goes up exponentially with lower specific impulse. Achieving the horizontal speed needed for orbit is much harder than just gaining altitude, so the 50km start isn’t enough to make it work. One ton ...


8

Think about what a sonic boom is. It's the shock wave caused by 'bunching up' of the compression waves of the body, moving through the air. To see this, consider: For a stationary body emitting pressure waves, at any one point in time you only hear the sound emitted at another (slightly older) point in time. However if the body is moving faster than the ...


6

If the boosters were closer together, like at separation, there is a complex interplay of shockwaves that produces lots of turbulence. If the vehicles stay in each other’s turbulence, it will need to be corrected for by the guidance system, probably using up more RCS fuel. These boosters are far enough apart during descent that they are outside of each other’...


6

Using the criteria in the Space Shuttle Missions Summary, namely Postponements are defined as launch delays which occurred prior to call-to-stations for OMI S0007 Shuttle Countdown. Scrubs are launch date changes after the start of Shuttle countdown (countdown was terminated or recycled to a later launch date). Delays are delays which occur only ...


6

In the case of the space shuttle: These two images show that the flame trenches at KSC point due south, and that the Orbiter's tail when installed on the pad also points due south. (source: Google Maps) (source: NASA) Therefore if the shuttle launched and went into a gravity turn in the desired heads-down attitude without rolling at all, it would have ...


5

The Falcon User manual provides some information: 4.5. Mission Accuracy Data As a liquid propellant vehicle with restart capability, Falcon 9 provides the flexibility required for payload insertion into orbit with higher eccentricity and for deploying multiple payloads into slightly different orbits. Until verified by actual operations, SpaceX ...


4

If you want to launch by government owned space agency ISRO, then you need to contact its commercial arm Antrix corporation. You can obtain a launch slot in one of the PSLV rockets. For a CubeSat it will be a piggyback ride alongwith the main spacecraft. ISRO does not provide dedicated launches for small satellites. However, there are some private launch ...


3

As the other answer says, flying to orbit on compressed CO2 is right out. Forget that approach. However, if you are willing to use the CO2 as propellant in a nuclear thermal reactor, that has at least been looked at and found plausible for Mars applications, so maybe it could work at Venus. Carbon Dioxide is the most readily accessible of all the ...


3

A little expansion on what Digger commented. Assuming you weigh 200lbs, 3 gees will make it feel like you weigh 600lbs. You could imagine it as a 400lb person sitting on you. That's definitely uncomfortable, but it's only for 8-9 minutes. It's not dangerous if you're otherwise healthy. Further, not only is it really not that many gees, but they're ...


3

Despite two answers that say "irrelevant" there can be some other second-order effects beyond the ones nicely described in @JayDawn's answer: If you are launching into a dawn-dusk Sun-synchronous orbit you would obviously be launching around dawn or dusk, and not mid-day or mid-night. If there are operations that are important to be recorded visually with ...


2

No, to hear a sonic boom, the object must not only be traveling faster than the speed of sound, but also it must be traveling towards you. If an object is moving towards you at less than the speed of sound, then the Doppler effect will cause you to perceive any sound it’s making as being a higher frequency. If it’s moving towards you faster than the speed ...


2

Here's a much better diagram (it's for Titan IIIe, but it's the same except for the upper stage, which doesn't feature in the question). Solid Rocket Motor (SRM) ignition followed by liftoff First stage ignition (trigger event: g-switches) SRM separation (trigger event: timer started by the g-switches) Second stage ignition / stage separation ("fire in the ...


1

There are 3 main reasons: Cost Safety Increase in dry mass Otherwise its a great idea. The cost thing is fairly straight forward, just crawling along form storage to the pad required a 2,721 ton US$14 million monster, and that peaked at 2 mph. Even if you where prepared to tolerate a significant g-load, what ever structure is getting your rocket to decent ...


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