Landing Convoy Ready on the Runway
Long before sonic booms rock Florida's Space Coast and a space shuttle glides to a stop, about 25 unique vehicles and their operators -- collectively called the landing convoy -- snake their way toward the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. Each one has a specific duty to make the shuttle safe to enter, assist the flight crew out and prepare the spacecraft for towing to a nearby processing hangar.
"When they say, 'We're definitely landing here, let's go,' it's neat to see everybody get in their vehicles and go out and support it," said Richard Merritt, a landing support manager with United Space Alliance. "It's a rather big group of people."
The nucleus of the operation is based in the Convoy Command Vehicle -- a 40-foot-long modified motor home with state-of-the-art video cameras and recorders, television monitors and a giant communications satellite antenna. It's also outfitted with a weather system to monitor the temperature, and wind speed and direction on the runway.
"It's basically like a mini firing room in there," Merritt said.
Inside the heart of the whole operation is the convoy commander, who stays in constant communication with the shuttle and all of the vehicles during post-landing activities. Immediately after wheelstop, he or she sends NASA Fire Rescue trucks out toward the shuttle. They remain a safe distance, though -- about 1,250 feet -- until safety sniff checks determine there are no hazardous gases radiating off the shuttle. Meanwhile, emergency helicopters are hovering nearby, just in case they are needed.
It's a dangerous job: heat sparks or flames could result in fire, fuel could cause permanent damage to skin, eyes or respiratory systems, and the main landing gear tires are so hot and full of pressure, they could rupture. To keep about 150 workers safe, they put on air-tight protective gear called self-contained atmospheric protective ensembles, or SCAPE suits. They also go through extensive training to pull off the extremely choreographed operation.
"We have to hook up within 30 minutes. It's very important to maintain cooling, maintain power in the orbiter," Merritt said. "So, in between launches and landings, we decided that we needed some kind of simulator practice."
Those practice runs are performed on the runway with a gigantic, yellow metal frame on wheels called an orbiter super simulator.
Once the shuttle is deemed safe, two convoys deploy on the runway -- a forward and an aft. The forward heads toward the nose of the shuttle with vehicles and personnel that remove time-sensitive payloads and experiments. Astronaut support personnel, called ASPs, also usher the flight crew members out of the shuttle, through the White Room truck and into their Crew Transport Vehicle where they undergo standard medical checks.
"When I was back on the runway here at KSC and you know you go through all the shutdown checks and stuff and you're talking to mission control and it finally comes to the point where the ASP wants you to get out of the seat so that he can take over, I didn't want to get out of the seat," said Bob Cabana, a veteran shuttle astronaut and current director of Kennedy. "I mean, this was my spaceship, I had it for, you know, two weeks on orbit... you can't have it back, I don't want to give it up."
Handing over the keys, so to speak, is quite an experience for workers on the ground, too.
United Space Alliance's Mike Parrish said, "When the vehicle lands on the runway, when you go into the vehicle, it almost smells like a musty locker room. So, when the crew comes out, they're asking, 'What is that smell?' It's the fresh air. We're looking around, 'What is that smell?' Just musty, you know, but it cleans up pretty good."
By now, the aft convoy has deployed from the Shuttle Landings Facility's midfield park site and it is operating on a very strict time clock.
First, a purge unit that pumps conditioned air into the shuttle moves into place. It sits on top of KAMAG transporter vehicle that was designed in Germany. Merritt describes it as a mine-type, low-rider vehicle with 18 wheels.
"The nice thing about the KAMAG is you can raise it up and down, and you can basically move it sideways if you need to," Merritt said.
Inside the KAMAG sits a spotter and a driver, who remain in constant contact with a move director. From there, the driver can control the height and speed of the vehicle. On top, technicians operate a boom carrying three purge ducts that can telescope out toward the shuttle.
"The orange hoses, they hook up to the orbiter on the right side," Merritt said. "They pump conditioned air into the orbiter to keep the toxic gases out, to keep any moisture out that doesn't need to be in there, and help cool the orbiter from flight."
Cooling the shuttle down from temperatures that reach almost 3,000 degrees Fahrenheit during re-entry is so critical it takes one more vehicle to get the job done -- it's an extra-long truck that resembles a home air conditioner unit on wheels. A few technicians are inside the control room of the cool truck monitoring the controls and pressures and keeping the convoy commander informed of the health of the spacecraft.
"It's got a Freon system in it that circulates and has a heat exchanger in the orbiter and circulates around that and takes the heat off the orbiter so we can stay powered up until we get into the OPF," Merritt said.
Finally, about four hours after wheelstop, the shuttle's hatch is closed and a diesel-powered tractor slowly tugs the spacecraft down a two-mile tow-way toward Kennedy's orbiter processing facilities, called OPFs. The journey marks the end of landing convoy operations -- another critical piece to NASA's human spaceflight program.
NASA's John F. Kennedy Space Center