근데왜 파일럿 가르칠때 평평하다고 하고 가르치냐?

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평평하고 자전도안한다고 생각하고 

운전하라고 하는거

왜그런거냐?

식도 다 그렇게 만들은거 왜그런거임

자전한다매 그거 계산 해야한느거아님?

https://www.nasa.gov/centers/dryden/pdf/88104main_H-1391.pdf

6page - >flaying over a flat, norotating earth.

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These days there's a popular trend when simulating things to simulate every possible mechanism we can imagine. Those who think that way would agree with you. Why would you ever make a flat Earth model when everything is eventually going to make its first flight on a real rotating spherical-ish Earth? This approach works great until you come across real development or computational limits. The cit

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ed paper is from 1988. Computers were much weaker back then. For perspective, the Cray Y-MP was sold that year. Its peak performance was 333 megaflops. She cost $15 million dollars. Contrast that to today. A Geforce GTX 1070 is capable of 6,500,000 megaflops (6.5 teraflops) and has a price tag of around $400. In those days, you didn't waste computational power on frivolities. It turns out that fo

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r a vast array of aeronautical problems, the effects of a flat earth vs. round are minimal (much less the effects of rotating vs. not). If you're shooting a shell 15km, and need it to land with pinpoint precision, you need all that extra complexity. However, many aero problems include a guidance unit which would address any error due to Coriolis effects or the spherical ground the same way it woul

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d handle any other errors. It'd simply see it wasn't on the right path and make a correction. The other sources of error here, such as winds, play a far larger effect in deviations from a flight plan, so all the rotating and spherical effects can just get lost in the noise.

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Even today, we still make flat Earth models. The reason is not computation time, like it was in 1988, but development time. The more things you model, the more things you need to develop, verify, and maintain. If a particular problem does not call for advanced models, why waste budget developing and maintaining them?

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A real life example of this shows up in geoids. Quite often we can do all the modeling we need with a spherical Earth. However, sometimes we find that we need to model the Earth with its proper oblate shape, so we them switch to the WGS84 geoid, or any one of its brethren. The price: all sorts of fun complexities.

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When I say I have a "forward/right/down" body rotation matrix, is the "down" vector towards the center of the earth, or is it perpendicular to the geoid? On a sphere, they're the same. On an oblate spheroid, I have to take the time to figure out which one was intended. If I don't take the time, then I might as well have just used a sphere.

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이말은 결국, 오늘날까지 바꿀필요가 없다는 얘기잖아..... 뭐냐고 그럼그말이

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문제 없던것에 손대지 않겠다. 그말인데 아이러니지

[에틸렌(bookbg)]

초음속으로 비행하는 거 아니면 곡률에 의해 기수가 들리는 현상은 무시할 정도라서

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우리는 그걸 평면지구라고 부르기로 했어요

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풉 ㅋㅋㅋ

[00(122.34)]

에틸렌 니도 뻔한 댓글은 고만좀 달아라ㅋㅋㅋ 수평선만 봐도 멀리 사라진 배 줌 땡기면 보이고 해서 곡률 어쩌고 저쩌고 하는 소리 맞지도 않는데 뭔ㅋㅋㅋ

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하아압!! 쿄우카 분신술!!!ㅋㅋㅋㅋㅋㅋ