Oomair said:
ok one thing i want to get straight in my head here is that does a space shuttle that is returning to orbit just dive into orbit at a high speed and makes a landing like a plane or does it stay in a suborbital area for a few hours by slowly coming down each atmospheric level so that the heat doesn't dissolve it?
It takes a little over an hour to start from deceleration burn to landing. And yes, you are right with your 2nd statement.
-It starts by deceleration burn
-Skips over the upper atmosphere, much like a skipping stone thrown over the surface of a lake
-By maintaining high angle of attack, you create a 'lot of drag' and the glide path steepens <-do that if you think you might overshoot your target landing area, conversely, you reduce angle of attack if you feel like coming short.
-You could also do a series of 'S-Turns' or steep break turns left and right to bleed more speed if you think you might overshoot
^^All of the above maneuvers are done above 200,000 ft traveling at hypersonic velocities.
When you have gone below hypersonic at lower altitudes, the glide bath then becomes more steep.
So to summarize, glide path during high altitude hypersonic phase is relatively shallow, done at high angle of attack(to expose the more heat resistant bottom tiles) and to experience the least heating possible(least aerodynamic pressures) but at a longer period of time. Once the craft have gone supersonic, lower altitude, and nearing the landing area, that's when the glide path becomes very steep, to have good speed for landing, and of course to make up for the space shuttle's very poor aerodynamic efficiency :)
