Editor's notes - these topics are ones which are mentioned in the book Columbia - Final Voyage, in Chapter 11 "A NASA Primer".
When assembled for launch the space shuttle consists of the 'orbiter' (vehicle), two 'Solid Rocket Boosters', and the 'External Tank'. The orbiter is the only portion which stays in space. It returns to Earth when the mission's completed.
The External Tank attaches to the shuttle structurally at three places - a Bipod (a two leg version of a tripod) near the shuttle's nose, and two aft attachments near the shuttle's tail. Each 'foot' of the bipod has a wedge-shaped piece of foam to prevent ice from forming.
Two 17 inch diameter pipes carry the hydrogen and oxygen propellants from the External Tank into the shuttle. After the tank is jettisoned automatic doors close over the umbilical openings. A set of automated cameras next to the umbilicals take photos of the External Tank after it separates from the shuttle.
Here's an animation of the External Tank falling away from Atlantis on the STS-112 mission.
Once in orbit the shuttle can point itself in any orientation needed to accomplish the mission's goals. Natural gravitational forces push the shuttle toward the 'gravity gradient' attitude where the engines point toward the middle of the Earth and the nose points toward deep space. This attitude is used for very sensitive microgravity experiments because it provides the best quality microgravity. Other important attitudes include LVLH (Local Vertical Local Horizontal) where the shuttle retains the same orientation relative to the Earth's surface, and solar inertial where an instrument inside the shuttle's cargo bay points toward the sun.
On STS-107 the primary cargo was the Spacehab module within Columbia's cargo bay. It featured dozens of facilities for different experiments; some automated, most operated by the crew. The secondary cargo was the FREESTAR bridge which included six payloads mounted behind the Spacehab module. Because STS-107 was a fairly long mission the "Extended Duration Orbiter" pallet was flown with additional hydrogen and oxygen tanks to increase the number of days Columbia could stay in space.
The cargo bay is unpressurized in space. Unless the astronauts are wearing spacesuits they're limited to the shuttle's crew cabin, the Spacehab pressurized module within the shuttle's cargo bay, and the tunnel which connects Spacehab to the crew cabin.
The space shuttle is permitted to fly in orbits inclined anywhere from 28.5 degrees to 57.1 degrees from the equator, with some unusual exceptions. The inclination is the maximum latitude the shuttle flies over during the mission. STS-107 was a 39 degree orbit, chosen to maximize the time over the Mediterranean Sea for the MEIDEX experiment.
The shuttle communicates with Mission Control via the TDRS (Tracking Data and Relay Satellite) constellation. Communications from the shuttle goes up to the satellites located 22,300 miles above the equator. The satellites relay voice, video, and data down to a ground station in White Sands New Mexico and then to Mission Control. Using TDRS permits the shuttle to remain in near continuous communications.
The Kennedy Space Center is located at Cape Canaveral in Florida. KSC is adjacent to the Cape Canaveral Air Station and the two share some facilities. Launch Pads 39A and 39B are used for the shuttle and were originally built for the Apollo moon program.
Most of the shuttle's exterior surfaces are covered by reusable thermal protection system tiles and blankets to protect the interior from the reentry heat. The areas which encounter the lowest heat are covered with white thermal blankets. The bottom of the wing and other areas which experience more heat are covered with black colored tiles.
The areas which encounter the highest amount of heat, including the nose and the leading (front) edge of the wings, are covered with Reinforced Carbon-Carbon (RCC) panels. The RCC are interconnected with "T-seals". Each T-seal snaps and bolts on to one side of an RCC and forms a tight fit between it and the next RCC panel. The T-seal interlocks with the RCC panel on one side and lies on top of the RCC panel on the opposite side. It’s similar in concept to a weather-strip on a door. Here's a NASA fact sheet on the shuttle's thermal protection system.
The RCC and T-seals are made from a rayon cloth graphitized and impregnated with a phenolic resin. This impregnated cloth is laid up as a laminate and cured in an autoclave. After being cured, the laminate is pyrolized to convert the resin to carbon. This is then impregnated with furfural alcohol in a vacuum chamber, then cured and pyrolized again to convert the furfural alcohol to carbon. This process is repeated three times and forms the body of the RCC. To protect the RCC the outer layers are chemically converted into an extremely tough material, silicon carbide.
A typical installation of an RCC panel on the leading edge of the shuttle's wing. Here a left hand RCC#6 panel is installed on Discovery.
The carbon dioxide exhaled by the crew is absorbed by Lithium Hydroxide (LiOH - pronounced "Lie Hoe"). As each oatmeal can size LiOH canister is saturated it's replaced by a fresh canister. During the mission the astronauts transmitted video of Willie McCool replacing one of the LiOH cans.
Columbia had 68 LiOH canisters onboard including two cans for the 13 rats. That was enough to last through four days after the planned landing with normal usage.
The Shuttle Training Aircraft (STA) is a modified Grumman Gulfstream II business jet. One side of the cockpit has been modified to look like the shuttle's cockpit and the plane's flying characteristics have been modified to make it fly like the shuttle when it's coming in for landing.
If an emergency occurs two to five minutes after launch the shuttle can make an emergency "U-turn" and come back to the Kennedy Space Center. The "Return To Launch Site" abort is considered extremely dynamic and tricky, but offers the crew some chance for survival if major problems occur during the launch. So far the only place an RTLS abort has been performed is in the simulators.
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