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SpaceShipOne Folds Its Wing

Posted on Tue, August 25, 2015
  • by: Tony Carp
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For the past decade, SpaceShipOne has been on display as one of the hanging artifacts in the Boeing Milestones of Flight Hall. It was specifically positioned to depict the aircraft in its initial stage of powered flight (30 degrees, nose up attitude) just after release from its White Knight mother ship, which carried it aloft to an altitude of about 14,326 meters (47,000 feet). In March of this year, SpaceShipOne was lowered to the floor as part of a major renovation of the Milestones gallery. During this time, it received a thorough condition assessment and photo documentation by conservator Sharon Norquest. After surface cleaning and minor conservation work is completed, it is scheduled to be rehung this week and will be one of the major artifacts in the new Boeing Milestones of Flight Hall, scheduled to open in July 2016. The renovation project provided us with a unique opportunity to consider how we showcase SpaceShipOne in the future. In discussions with curator Valerie Neal, the Milestones project team decided to pursue a new display orientation for SpaceShipOne. The team wanted to depict the aircraft as if it were in its initial reentry flight, when its unique “feather system” is deployed.

SpaceShipOne

SpaceShipOne, the first privately built and piloted vehicle to reach space.

To accomplish this, a dialog was initiated with Scaled Composites project engineer Matt Stinemetze and crew chief Steve Losey. Both Stinemetze and Losey had been with the program from the beginning to design, build, test, and fly the vehicle that would eventually win the $10 million X-Prize competition. Consulting with these key team members gave us the insight we needed to understand how SpaceShipOne’s onboard feather system functioned; the rear half of the wing, along with both tail booms, are raised to a 65 degree angle by using two redundant pneumatic actuators. The feather was Burt Rutan’s, an American aerospace engineer, novel approach to the problem of heat build-up during the reentry phase of flight. It allowed for an aerodynamically stable and controlled craft to drop back into the atmosphere without generating surface temperatures that could have melted the resin that bonds the carbon fiber skin together. For a successful display in our museum environment, a few specific challenges had to be met. First, the shift in the aircraft’s vertical and longitudinal center of gravity in the proposed display configuration had to be assessed before a new hanging scheme could be designed. The new rigging elements will display the craft in a 20 degree, nose down (pitch) attitude while remaining perfectly balanced. Our next challenge was how to keep the configuration locked. While in operation, the feather is held in the raised position by air pressure only; there are no “up” locks. Since we will display the artifact in the reentry configuration for years, we needed to provide a mechanical means of keeping the feather deployed. Gary Gordon, our collections department in-house machinist, fabricated aluminum collars that fit over the actuator pistons to keep them from retracting back into their cylinders should a loss of system pressure occur over time. We performed two trial deployments of the feather to ensure the proper design and fit of the collars, and we also verified the volume of space the aircraft needs in the gallery to be suspended in this configuration. The artifact takes up about 6 meters (20 feet) of vertical height in the new configuration. We operated the feather system by following the normal flight procedure using levers and gauges in the cockpit. This meant pressuring the system via a quick-connect service port, which services all four onboard air bottles simultaneously. However, I did not recognize the quick-connect fitting as standard aerospace hardware. As it turns out, and owing to the experimental nature of the craft, the fitting is the same type as used for a paintball marker!

SpaceShipOne With Feathering Deployed

SpaceShipOne with its iconic feathering deployed in the Museum's Boeing Milestones of Flight Hall. 

The revamped display will provide visitors with a new perspective on the most distinctive feature of this one-of-a-kind artifact.