Superbolt® Secures NASA’s Orion Pad Abort-1 Success
On May 6, 2010, NASA successfully launched the Orion Pad Abort-1 flight test from White Sands Missile Range in New Mexico. This critical test proved that the Orion spacecraft could safely perform an emergency escape from the launch pad – an essential capability for astronaut safety. Behind the scenes, advanced engineering and innovative fastening solutions played a key role in making this mission possible. Among them, Superbolt® multi-jackbolt tensioners stood out as a game-changing technology.
Engineering Challenges
The Orion Pad Abort-1 test involved separating a full-scale crew capsule (measuring 4.8 meters in diameter and weighing 8,200 kg) from its Launch Abort System (LAS). This separation had to happen quickly, safely, and under extreme conditions. NASA engineers faced several challenges during development, including:
- Defining shock environments
- Managing installation complexity
- Ensuring fast and reliable separation
- Validating load paths
- Handling increased design loads
To address these, NASA designed a retention and release (R&R) mechanism with six structural connections between the LAS and the crew module simulator. Each connection featured:
- A preloaded tension tie
- A Superbolt torque nut
- A frangible nut (designed to split during separation)
During the flight, the frangible nuts were pyrotechnically split, allowing the crew module to cleanly separate from the LAS. This event created significant shock forces, which had to be measured and managed to protect nearby hardware. Lockheed Martin’s test team recorded the shock levels and found that the actual environment was 90% lower than predicted at 100 Hz – an impressive result that helped validate the design.
The Benefits of Choosing Superbolt
NASA utilized Superbolt torque nuts for this test for several key reasons:
- Consistent preload: Lab tests showed only 4% preload loss over 30 days, with 2.5% in the first 24 hours.
- Efficient energy transfer: 50-75% of the strain energy was converted into kinetic energy during separation.
- Precise load control: Strain gauges on each tension tie ensured pure tensile loads were applied after stacking at the launch pad.
Even with some challenges, like temperature effects on data acquisition and occasional strain gauge failures, Superbolt’s performance remained dependable.
Beyond the Crew Module: Forward Bay Cover Separation
The Forward Bay Cover (FBC), which protected parachutes and other hardware, also needed to separate cleanly during the test. This was achieved using another R&R mechanism with three preloaded separation bolts and three jettison thrusters.
These thrusters pushed the 84 kg FBC away from the crew module. Despite complex loading and structural challenges, full-scale ground tests confirmed a nearly straight and successful separation.
Both the LAS and FBC systems used lanyard-pull electrical connectors, and extensive testing ensured they performed reliably, even under conditions harsher than manufacturer recommendations.
Conclusion
NASA’s Orion Pad Abort-1 test was a landmark achievement in spacecraft safety, and Superbolt played a vital role in making it happen. By utilizing Superbolt torque nuts, engineers gained better control, reliability, and performance under extreme conditions. Whether in aerospace, shipbuilding, or heavy industry, Superbolt continues to prove its value in mission-critical applications.