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MeetingsBrowserlast Friday at 10:11 PM3 repliesview on HN

This is really neat and pretty fun to play around with!

How accurate are the simulations? I'm able to get orbit by turning 45 degrees as soon as I launch and then doing some minor burns at the height of the initial trajectory.

I don't feel like this strategy would work in real life.


Replies

donutthejedilast Friday at 10:53 PM

Its fairly accurate as far as I can tell. Your right about the fact that It wouldnt work in real life due to the dynamic pressure your exerting on your rocket, using your method you get to about 150 kPa, Falcon 9 usually maxes out around 35 kPa so it would explode. Also it is a fairly fuel inneficent way of getting into orbit, but yes it is possible

Intralexicallast Friday at 11:49 PM

Subtracting gravity losses, the largest effect of your 45 degree thrust vector would be sideways acceleration. Which is generally what you want, to get up to speed as quickly as possible, instead of wasting energy ascending vertically.

We just don't do it on Earth because we need to get out of the atmosphere first for efficiency and structural reasons. But on the moon or another vacuum body, "diagonal kick followed by minor circularization burns at apogee" is pretty close to the optimal strategy. Even on Earth, it's similar to the trajectories proposed by SpinLaunch and other "space cannon" concepts.

GalaxyNovalast Friday at 10:12 PM

I think it would, given that there is no air resistance.