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8

There's a lot of variations in the astronauts' subjective impressions of the sound: "muffled roar", "gutteral roar", and allusions to infrasonic vibration, for which "rumble" might be a fair description. Collins, in Carrying The Fire: Trust your instruments, not your body, the modern pilot is always told, but this beast is best felt. Shake, rattle, and ...


6

“Sailing a rhumb line” means holding a constant compass bearing. For short distances, this stays close to a great circle path.But at longer distances and/or higher inclinations, the rhumb-line path “tends north” of a great circle as shown in the Questions globular image. For a fast, short launch, a rhumb-line trajectory has the advantage of simplicity. As ...


4

The engines on the Delta IV Heavy, like most large liquid-fueled engines, can gimbal, vectoring up to 6º in any direction, so any mass imbalance can be corrected for almost instantly. That said, it would also be possible to just start with a couple hundred kg of propellant more in the tanks on the booster that lights first; propellant tanks are generally ...


3

I'm just going to add some considerations about tidal forces, thanks to @Steve Linton for mentioning this: Crushed by the moon The tidal force (https://en.wikipedia.org/wiki/Tidal_force) from the moon is rather small, about $10^{-12} m/s^2/m$. This is not a serious problem. Crushed by the spacecraft When a spacecraft lands on the runway, it exerts ...


3

https://lifeboat.com/em/arrestor.pdf "An Orbiting Magnetic Arrest System for Rocket-Free Transportation to Earth Orbit" If transport to earth orbit could be decoupled into the two separate tasks of reaching orbital altitude and maintaining an orbit, rocket-free transportation to orbit would be possible with straightforward improvements to existing ...


2

Partial answer (throttle settings): Throttle settings varied per flight, and NASA quit publishing these Mission Reports a long time ago. But here are some numbers to get you started, from STS-81 (the last one I could find online). For the 3-G throttling that starts at 012:09:34:51.537 and ends at 012:09:35:48.513 you can assume a linear ramp on the ...


2

There are fundamentally 2 things at play here: the pressure of the rocket exhaust, and the atmospheric pressure. As a rocket ascends, eventually the atmospheric pressure will drop enough that this occurs. When this happens, however depends on the pressure of the rocket exhaust. This in turn is dependent on nozzle shape, exhaust velocity, and a bunch of ...


2

Notes On Prior Art I have had this concept up at wikiversity for a while now, and recently initiated a conversation with the OP on twitter, which is how this question got started. What inspired me to start thinking about it at first was a reddit comment from Dani Eder about the possibility of landing on the Moon using a metal coated track and magnetic ...


2

This is one of a whole bunch of space launch ideas that all involve "loading up" a massive orbiting object of some kind with energy and angular momentum. Then you somehow attach it to a relatively small payload of some kind and transfer angular momentum and energy to the payload. As a rather extreme example, you could put a very small payload into orbit by ...


1

In response to two of your questions: Is it naturally stable? No. Tidal forces will tend to torque anything in orbit so that its long axis points in the radial direction; in order to keep your launch ribbon horizontal, you'll need active measures to counteract this. Things get worse when you realize that in the 25 seconds you need for your spaceship to ...


1

Recently, I am also looking into this approach. It seems that carbon nanotube (CNT) fibers might be a promising option in the near future of 'rocket-launch-via-cable', due to its excellent conductivity and high strength. --------- Here are some ideas and calculations ---------- Consider the electric cable made of Carbon Nanotube Fibers with diameter $1mm$ ...


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