Why does the Space Shuttle turn and roll over during its atmospheric flight?

Question

Doesn't it have to do with the pad facing the wrong direction! If so, why does the shuttle have to launch in a specific direction? IDK just a question i thought i'd ask.

Answer 1

You have the right answer. The pad faces in a neutral position so any usable launch azimuth can be reached. The shuttle rolls in order to get onto it's required course. The roll doesn't bother the astronauts because they are being pushed back into their seats by the acceleration of the shuttle.

The reason a specific direction is necessary is the same reason they have "launch windows". As an object (say, the ISS) orbits the earth it's orbital path over the earth changes due to the earth's movement about the sun (the orbit stays in the same direction relative to the stars). So, the ISS orbit isn't attainable from the same direction all the time. Hence, the shuttle has to be able to launch into an orbit parallel with and directly below the ISS, and so they program a roll to get the shuttle headed correctly.

Answer 2

There are several of reasons the shuttle rolls over.

First, distribution of weight. The shuttle as it sits on the launch pad attached to the rocket makes the combination unstable because it is not symmetrical. The center of gravity is off the center line of the main rocket booster + fuel tank towards the shuttle. It is easier to balance thrust if the center of gravity is below rather than on top and to do that, the shuttle has to be under the main rocket booster and fuel tank.

Second, if there is an emergency, the shuttle can separate from the main rocket booster and come DOWN easier if it is under the booster. If it were sitting on top, it would first have to go UP to get away from the booster before it can come down.

Lastly, the "shuttle system" is a make-do system. The original design was similar to the Rutan design, where the shuttle would ride up on the back of a launch plane and then launch when it got to altitude. In the original design, the shuttle crew would not have to be upside down during the initial launch phase as the shuttle would be on top of the launch plane like it sits on top of the 747 transport plane. The launch plane part of the system had to be dropped off when Congress refused to give NASA the money needed to build both the shuttle and the launch plane. So to "make do" NASA came up with the booster system, much to our regret when the Challenger blew up.

Lastly, NASA in it's early days had a saying. "You can have it fast, safe or cheap. Pick two." NASA with the shuttle system tried to go with safe and cheap but only got cheap.

Answer 3

For the same reason that a football thrown with spin travels straighter, the spiraling motion of the shuttle keeps it on a better heading. The shuttle has no steering power during the lauch, it can't correct left or right to stabilize it, so they initiate a roll to keep it going in the right direction.

Answer 4

Unlike airplanes, which fly with the cockpit facing up, away from the earth's surface, the space shuttle rolls over with the cockpit facing down, or towards the earth.

Answer 5

I always thought that the tiles on the belly protected the ship and crew better from solar radiation

Answer 6

To keep it on a better heading so it doesn't drift off course. They have no control while reentering the earths atmosphere and while leaving it.

Answer 7

You voyeur you! (Maybe friction) Devil!