NASA's Orion spacecraft tested in anticipation of maiden flight
By Anthony Wood
April 29, 2014
NASA has successfully completed the latest series of tests for its next-generation Orion Spacecraft, currently housed at the Kennedy Space Center. The latest trials focused on vibration-testing the spacecraft, simulating the stress that Orion will be subjected to during its maiden test flight scheduled to take place in December.
Orion is due to serve as NASA's go-to vehicle for both low-Earth orbit and manned deep space missions. NASA boasts that Orion will be the most advanced and safest spacecraft ever designed, allowing manned spaceflight to reach hitherto impossible destinations, including missions to near-Earth asteroids, and in the longer term, a trip to Mars.
The most recent set of tests, carried out between April 17-24, was conducted by NASA scientists alongside a team from Lockheed Martin, in order to simulate the high levels of stress that the prototype spaceship will be subjected to during its maiden test flight. Orion was placed in a specialized vibration stand, isolated from the floor and ceiling, with sensitive components such as the spacecraft's windows, thrusters and parachutes covered and cantilevered in order to protect them from the jarring ordeal.
Twin electromagnetic shakers were fitted to either side of the spacecraft's hull, each of which was capable of simulating 4,000 pounds of force. Once one area of the craft was stress-tested, the shakers were removed and attached to another segment of the hull, continuing the process until Orion was fully tested. As the shakers were operational, readings were taken from accelerometers and strain gauges placed throughout the crew compartment, informing the team whether any elements of the design had failed to perform within expected parameters. Following each stage of stress testing, the hull of the spacecraft was thoroughly checked by system specialists for flaws that may have been exposed under pressure.
"It was a great accomplishment for the test team in preparation for the Exploration Flight Test-1 later this year," states Orion Program Test and Verification lead scientist Rafael Garcia. "Following months of preparations and pretest analysis, the multi-point random vibration test was conducted without any major issues and was completed two days ahead of schedule."
Orion's first test flight, due to take place this December, will take the form of the uncrewed spacecraft being launched into space to test critical systems whilst being subjected to punishing pressures. Once in space it will complete one full orbit, and before its return to Earth it will fire its thrusters one more time, pushing the spacecraft to a height of 3,600 miles (5,794 km) above the Earth.
This will be done in order to increase the pressure upon re-entry. At that time, at a speed of around 20,000 mph (32,187 km/h) and withstanding temperatures of 4,000ºF ( 2,204ºC), the spacecraft's heat shield will be put under extreme pressure. This is a vital test, required to determine whether the craft could adequately protect a human crew on a return mission from outer space. The maiden voyage will come to an end with the craft deploying its parachutes, and coming to rest in the Pacific Ocean.
The video below displays a computer simulation of the maiden test flight.