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Video shot from the Space Shuttle during launch

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Re: Video shot from the Space Shuttle during launch

#61

Earlier quoted context omitted.

> just try thinking about conducting the same situation with out an atmosphere. I can't since they DID travel through the atmosphere.

you can't imagine a simple physics problem? i understand that they DID travel through an atmosphere, but the basic mechanics involved can be understood just using projectile motion equation without taking the effects of air drag.

what are you talking about? in this example they were travelling through atmosphere.

Re: Video shot from the Space Shuttle during launch

#62

Earlier quoted context omitted.

You watched the video right? Looks quite a bit more dangerous than you're average jumbo jet takeoff.

yeah. how come that 2 pieces of foam (?) detached so quickly at the begging. was it intentional? whats the reasoning behind?

The big fuel tank has significant foam insulation because its two major fuel components are kept very cold (liquid oxygen at -300F/-180C; liquid hydrogen at -420F/-250C) and the external surface gets fairly hot at the speeds the shuttle travels.

Lockheed designed the tank with insulation outside the main shell, and it's never held together very well. I've spoken to retired engineers from another company who designed a competing tank with internal insulation; they're still upset their version didn't get picked. I've never heard a clear explanation as to the specific reasoning for Lockheed or NASA's decisions.

Of particular note, the Columbia disaster was caused by one of those foam pieces breaking off during takeoff and damaging the thermal protective tiles on the shuttle's wing. During re-entry, the edge of the wings reaches a temperature of around 3000 F; damage to the protective tiles basically allowed hot air to burn through the wing.

Re: Video shot from the Space Shuttle during launch

#63

Earlier quoted context omitted.

The shuttle isn't going straight upward at separation. It's actually going mostly eastward, so when the boosters separate they retain most of their speed, and even regain a bit as they drop through the ultra-thin upper atmosphere. You're right about the rest -- a decrease to terminal velocity and then a big decrease as the chutes take effect. See also: http://en.wikipedia.org/wiki/Space_shuttle#Launch

But there wasn't a big decrease when the chutes deployed. It took a while. I found that odd. I expected an immediate decrease in speed the second the chutes deployed. Maybe the counter wasn't synched with the video?

> "there wasn't a big decrease when the chutes deployed. It took a while."

They take some time to completely expand. They're actually deployed in a constricted ("reefed") configuration, and then after several seconds they're allowed to fully open.

They're also trying to slow down a large piece of metal -- the booster rockets are about 150 feet long and weigh about 200,000 pounds (empty weight) each. The chutes produce a lot of force, but they're pulling on a lot of mass too (acceleration = force/mass.)

See also: http://en.wikipedia.org/wiki/Space_Shuttle_Solid_Rocket_Boos...

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