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nightranchers
2014-Jan-20, 12:11 AM
I just finished reading Bad Astronomy the book and was wondering why in chapter 24, example 3 of Hollywood Bad Astronomy, Phil says "Tilting the wings of the plane helps redirect the thrust to the side, turning the plane." I'm not sure why he used 'thrust' as the word instead of 'lift'.

Solfe
2014-Jan-20, 01:59 AM
Turning causes deceleration and decreases lift. Pilots will pull back or increase speed to counteract this... in a plane. In that chapter, he is alluding to the fact there is no air in space and therefore no lift so spaceships shouldn't bank.

There is a minor caveat, since firing off a thruster will cause the ship to rotate, and then firing the main engine causes a curved path, you may want to tilt the spaceship so your head doesn't kiss the side of canopy. Basically, the pilot would want to have his head pushed back and not sideways. I am pretty sure every real spaceship has seat belts and padding plus some very controlled thrusting to prevent this, the concept of fast and powerful engines is a good way to show ships spinning and tilting for movies and TV.

Babylon 5 did a great job of it, Space: Above and Beyond gave a tiny taste, and BSG sort of got it right. Space: Above and Beyond was kind of hit or miss, sometimes they nailed things while other times they simply had "space airplanes". In the Pilot of S:AAB, they showed a ship turning by switching off engines, it seemed a little too effective for spaceflight, I would think you'd need drag to make it work quickly. BSG tended to have Vipers do snapping spins before the main engine kicked in; Vipers rotate, thrust and counter thrust to turn so the pilot didn't eat the side of the cockpit. They also showed pilots working out with weights.