NASA's Shuttle Carrier Aircraft, a modified Boeing 747, carries Boeing's Phantom Ray during a test flight on Dec. 13 in St. Louis.

December 13 was frigid in St. Louis with the temperature about 16 degrees, but it was a good day to fly, especially for one of NASA’s Shuttle Carrier Aircraft (SCA) and Boeing’s Phantom Ray. The two aircraft made aviation history on the same flight, thanks to some way-out-of-the-box thinking and a special adapter, both courtesy of Boeing engineers.

“I have to admit that when the idea of using the SCA to transport the Phantom Ray was first proposed, there was some level of apprehension on my part,” said Craig Brown, Phantom Ray program manager. “However, once the idea started to take shape and we began meeting with NASA, my apprehension quickly turned to excitement. Pulling it off in such a short amount of time is a real credit to the Phantom Ray team and NASA, and is a real feat of engineering.”

The flight marked the first time in the SCA’s 33-year history that an aircraft other than a space shuttle orbiter hitched a ride on the back of the modified Boeing 747.  The engineering and planning behind the special flight were more than a year in the making as NASA and Boeing worked out the details through a commercial space act agreement.

Boeing's Phantom Ray unmanned airborne system sits atop a NASA Shuttle Carrier Aircraft prior to takeoff Dec. 13 at Lambert International Airport in St. Louis.

The Phantom Ray and the adapter weigh approximately 30,000 pounds together, but weight was not an issue, since the shuttle orbiter weighs 220,000 pounds while being ferried on an SCA.

“That wasn’t a concern,” said Jill Brigham, NASA engineering branch chief. “All of the computational fluid dynamics analyses that we did showed that there really wasn’t any concern from any aerodynamic effects, and the structural analysis showed that the aircraft and Phantom Ray hardware were more than strong enough.”

“NASA and Boeing have worked together many times through a space act agreement, so our biggest concern had nothing to do with the engineering, it was the weather,” said Brown. “The first flight was canceled because of rain and thick cloud cover, but when it cleared up two days later, despite being bitterly cold, the SCA took off and the rest – as they say – is history.”

During November’s low-speed taxi tests at Lambert International Airport in St. Louis (shown above), Phantom Ray communicated with the ground control station, received orders and made its way down the runway multiple times, allowing program officials to assess its performance and monitor the advanced systems on board.

This historic SCA flight took place almost one month after another major milestone for Phantom Ray at Lambert-St. Louis International Airport. On Nov. 18, Phantom Ray performed multiple low-speed taxi tests, allowing program officials to assess Phantom Ray’s performance and monitor the advanced systems on board. The taxi tests were the last tests the program needed to conduct in St. Louis before the program moved to the Dryden Flight Research Center at Edwards Air Force Base, Calif.

For the test flight, the SCA took to the wintry blue skies around St. Louis where it climbed to approximately 14,000 feet, allowing engineers in a chase plane to ensure the Phantom Ray, the adapter and the SCA performed well and could withstand the much longer flight to California.

 

NASA's Shuttle Carrier Aircraft (SCA), carrying Boeing's Phantom Ray unmanned airborne system, takes to the skies Dec. 13 for a test flight at Lambert International Airport in St. Louis. The SCA transported Phantom Ray to Edwards Air Force Base, Calif., the following day.

“It was a sense of excitement and a bit of relief I guess after all the hard work both teams accomplished,” Brigham said. “It was just exciting to watch it take off on a beautiful St. Louis day.”

Following the 50-minute flight in St. Louis, the SCA landed and taxied back to its starting point for a post-flight inspection. The following day, the SCA and Phantom Ray completed the 1,800-mile journey to California where Phantom Ray will make a series of test flights. However, those flights will be under its own power.

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