Wednesday, December 10, 2008
The $1.8M Alternate!
How would you like to be on a flight and have a weather diversion cost 1.8 million dollars? That’s the estimated cost of manpower, materials and fuel it takes to land the space shuttle at Edwards AFB in California instead of at its home base at Florida’s Cape Canaveral." />
Packaging the shuttle up requires quite a bit of work: 24/7 to be exact. Crews, flown in from Florida, are working around the clock (with a target time of seven days) to ready the shuttle for its ride home. The readying process starts off with the attachment of a lifting sling, then hoisting the spacecraft in a specially constructed, 90-foot-high gantry crane, where a precursory inspection is conducted. Further work includes defueling hydrazine rocket fuel (highly toxic; used for reactionary jets, reentry boosters and onboard APUs) and locking the rocket engines and aerodynamic control surfaces into transit positions. A giant tailcone—constructed of conventional-aircraft aluminum materials and designed to reduce drag, protect the reusable rocket engines and assure a cleaner airflow to the 747’s vertical stabilizer—is attached (with a struggle) to the shuttle using only eight primary bolts. (To return the huge structure back to California, the entire tailcone breaks down into six major pieces and is transported by ground.) Two complete cones exist, one that waits, assembled, at Edwards and one that’s broken down in boxes, in transit or in storage.
Once the prep work is complete, the shuttle is lifted approximately 60 feet, and the 747 is towed underneath. The shuttle is then lowered into place and secured atop the mother ship. Cruising at 230 knots, the 747 remains below 18,000 feet and has a light fuel load warranting at least two fuel stops along the way—the cross-country flight lasts two to three days. This ride is nearly the only time that the shuttle is in an inert or powered-down state. (On the ground, its systems are powered and protected by huge support vehicles attached via an umbilici consisting of hoses, wires and ducting.) The ferry route is carefully chosen and scouted by a lead plane that flies 100 miles ahead to avoid all wet weather and freezing conditions. Only essential flight crew are allowed on the 747; support crew and equipment are carried in the lead plane. The payload of the shuttle (roughly 20,000 pounds) is left intact for the ride back to Florida; only time-sensitive materials are removed at Edwards, and the rest is tended to in Florida, where the permanent processing facilities await.
The STS-126 mission marks the 52nd time the shuttle has landed in California, leaving only nine (or possibly ten) more opportunities for another (expensive!) visit to The Golden State. The Endeavour/747 pair departed from Edwards early Wednesday morning; visit www.nasa.gov/mission_pages/shuttle/main for updates from NASA on the cross-country journey.