13.12.2021

"We hope to have it in place at the museum in April."

The cockpit of the restored space shuttle motion simulator.

Every NASA astronaut who ever rode aboard the space shuttle, more than 350 of them, first sat in its full-motion simulator. And even though the simulator was firmly on the ground, anchored inside Building 5 at Johnson Space Center, it offered one hell of a ride.

"It was absolutely identical to what we flew," says Bonnie Dunbar, a former NASA astronaut who launched on the space shuttle five times from 1985 to 1998. "It rolled over on its back. It would vibrate as if you were going through a launch and landed like a shuttle entry. If you wanted to go into space, you had to pass the training in the motion simulator."

After the space shuttle was retired in 2011, artifacts from the program were sent across the country to various museums. Precious little of the shuttle actually remained in Texas, where the program was managed and its astronauts were trained. Texas A&M University sought to keep the full-motion space shuttle simulator, however. The chair of the aerospace engineering department at Texas A&M, Dimitris Lagoudas, led the effort to raise $500,000 and move the simulator to the university's campus in 2012.

The bulky simulator, with its extended runs of cables, had to be disassembled for the trip. Upon reaching the university, the simulator was put into a large building on campus with enough room to reassemble the simulator and put it on display. Unfortunately, shortly after this, the university unexpectedly lost control of this building. The simulator had to be moved into a smaller storage area not amenable to reconstruction work.

There, it gathered dust.

Saving the simulator

It remained there until Dunbar became a professor of engineering at Texas A&M in 2016. She had the right blend of expertise as an astronaut and curator, having served as president and CEO of The Museum of Flight in Seattle from 2005 to 2010. Dunbar was tasked with finding a suitable home for the simulator.

After it became clear that Texas A&M did not have the space to refurbish and display the artifact, she enlisted the help of two Houston space legends, former Johnson Space Center directors George Abbey and Gerry Griffin. This "Friends of the Simulator" committee began searching for a final home while raising money to move and restore the simulator. Abbey praised Dunbar's efforts.

"Starting in 1976, every crew that flew on the shuttle onward trained on this simulator," Abbey said. "It was an artifact that needed to be preserved. This would not have happened without Bonnie."

With their help, the pieces soon began to fall into place for Dunbar. The Lone Star Flight Museum, located in southeast Houston, near Johnson Space Center, agreed to become the new home for the simulator and provide adequate space for a public display. Carl Brainerd, who managed the simulator for three decades when astronauts trained on it, agreed to supervise its restoration. Finally, then-director of Johnson Space Center Mark Geyer agreed to house the simulator during its reconstruction at the NASA facility, providing a safe place for restorers to meet and work.

Two tractor-trailers delivered the simulator to NASA in Houston earlier this year, and by mid-November, with more than 4,000 volunteer hours invested so far, the interior of the simulator was completely restored. It was no easy task.

A beast to restore

The shuttle simulator, with its motion base, was an incredibly complex system. It trained not just the crew but also flight controllers in Mission Control. This meant the simulator had to send a complete telemetry stream to Mission Control that would appear to be "real" to computers there. Because the shuttle had a robust telemetry system, creating a high-fidelity simulation required lots of computing power, programing, and thousands of meters of cables.

Additionally, all of the on-board systems had to be programmed to simulate not just launch and landing but also thousands of scenarios and malfunctions. Visual displays had to be generated for the shuttle's windows covering the entire mission, from launch to landing, showing clouds, star fields, landing sites, the payload bay, the shuttle's remote manipulator system operation, and the varying payloads for each flight.

Brainerd said there was no practical way the computer complex that was needed to run the simulator again could be reassembled. The electronics are now obsolete. And the museum would not have the resources to maintain and operate the simulator. Much of the restoration work has therefore focused on cleaning the simulator, reinstalling removed items, and ensuring that the static display looks and sounds just as it did during training simulations.

"Our big project was replacing all the incandescent lighting in the cockpit with LEDs, plus purchasing new power supplies for the lighting," Brainerd said. "This was not as easy as it might sound. The internal illumination for all those switch panels was accomplished via 1,600 tiny incandescent bulbs that were soldered onto printed circuit boards on the backs of the panels. Once we found LEDs of the proper size and rating to fit into the available space, we had to unsolder the 1,600 bulbs and solder 1,600 LEDs in their place."

During crew training for the final shuttle mission in 2011, STS-135, with the astronauts' approval, Brainerd recorded their simulator sessions. This means the restoration team has cockpit displays, out-of-window views, and perhaps most notably all, the internal cockpit conversation during the training.

"We will have these integrated videos running on a TV in the rear of the cockpit and also at a console outside of the simulator," Brainerd said. "The audio will be piped into the cockpit via the simulator's original aural cue speakers. Therefore, to a visitor in the simulator, it will sound like a training session is in progress."

The final restoration step is painting the simulator, scheduled to happen early next year, and building exhibits to put on display alongside it.

"We're kind of in the home stretch," Dunbar said. "We hope to have it in place at the museum in April, in time to celebrate the anniversary of the first shuttle flight."

The Lone Star Flight Museum still needs funding to complete the displays for the simulator exhibit. Donations to support this final step of restoration, earmarked to the "SMS-MB restoration," can be made here.

Quelle: arsTechnica