The media must be oversimplifying how the Shuttle “flies like a glider” or “falls like a brick” during landing. Despite how math and physics tells us how to calculate a projectile problem, no two landings are ever going to be exactly the same (some things you simply cannot calculate). At one point, the media stated that only two crew members have any control during descent/landing (IIRC, Commander and Lt. Commander). But, furthermore, the landing is mostly computer controlled. So, I wonder…
a) What really takes place during a shuttle landing to adjust for varying conditions (wind speeds, etc.), during a landing? Is it strictly limited to attitude adjustments or are there any minute impulse engines to shim things a bit, in any fashion?
b) What percent is computer controlled vs. manually controlled? I WAG the computer is constantly making adjustments, and the manual controls are only for emergency override, if needed?
Surely there’s at least a little bit more than what meets the eye, wouldn’t you WAG?
What is the difference between “attitude adjustment,” which means changing the orientation of the craft to keep it going where they want it to, and “minute impulse engines to shim things a bit”? Do you mean to ask if adjustments are made entirely by control surfaces (elevons, etc.) or if there are thrusters involved?
Total dead-stick glider. They have control surfaces, just like on any plane, but no power whatsoever.
I believe the shuttle has a glide ratio of 1:1, which is a 45 degree descent. It has to do a big, honkin’ dive at the earth to pick up speed, then pull out when it has enough speed to fly horizontal for a little bit, otherwise it’d just pancake.
It’s true that there is no power at all. However, if the shuttle simply glided straight in for landing it would overshoot the runway considerably. The shuttle computer does what are called S-turns to bleed off excess energy as the shuttle descends. In other word the shuttle has extra potential energy in the form of altitude that it can use as power to stretch the glide. Once it is assured that the runway can be made, the computer will initiate a series of S-turns to bleed off uneeded energy.
The computer controls the shuttle during reentry, then the crew takes manual control when the orbiter slows down to subsonic speeds (NASA website mentioned above explains this).
At one of the numerous space mueseums in Huntsville, Alabama there is a space shuttle simulator that simulates landing the shuttle. I don’t know how realistic it is, but there is a system to keep the right glide angle and path. A circle is on your display and you have to keep a dot in the middle of that circle by adjusting the controls. Again, I don’t know if they actually have this for the astronauts when they land, but I’m sure they have something that makes it not too difficult to fly. They have to watch a lot of gauges and are pretty busy I assume. In the simulator, most people were able to land the shuttle without crashing.
