RocketSTEM Issue #9 - October 2014 | Page 60

Artist’s rendering of the Orion capsule as it separates from the Service Module during its upcoming test flight. Credit: NASA Orion’s December flight test critical for deep space human exploration plans By Mike Killian This December, after years of hard work from a team spanning across the United States, NASA will put America’s future deep-space human exploration spacecraft to the test, flying it further than any human-rated spacecraft has been in over 40 years. The highly anticipated mission, known as Exploration Flight Test-1 (or EFT-1), will put the agency’s unmanned Orion capsule into action to validate the spacecraft’s design, with the data collected being used to further perfect Orion’s capabilities before NASA puts astronauts onboard for deep-space crewed missions starting early next decade. The upcoming 4.5 hour orbital flight test is currently scheduled to launch from Cape Canaveral Air Force Station in Fla. shortly after 8:00 a.m. EDT on December 4, thundering skyward atop one of the largest and most powerful launch vehicles in history; the mammoth United Launch Alliance (ULA) Delta-IV Heavy rocket. After its first orbit (two hours after liftoff) Orion will perform 58 58 a burn to reach an altitude of more than 3,600 miles—15 times higher than the orbit of the International Space Station and 10 times higher than any human-rated spacecraft has been since 1972, when the crew of Apollo 17 visited the Moon. Doing so will give engineers the opportunity to evaluate Orion’s performance in a way only a real spaceflight can; computer simulations, scale model tests, and ground testing only goes so far. While NASA’s iconic Space Shuttles carried out missions in low-Earth orbit, Orion is intended to fly astronauts on deep space missions, and so Orion will hit Earth’s atmosphere on reentry much faster, and harder, than the Space Shuttle did. The Shuttles hit the atmosphere on reentry at around 17,000 mph; when Orion returns on the EFT-1 mission it will hit the atmosphere at 20,000 mph, bringing hotter reentry temperatures of up to 4,000 degrees Fahrenheit to go with its faster velocity, simulating a return from a deep space mission and giving engineers the opportunity to evaluate its launch and high speed re-entry systems, avionics, attitude control, parachutes, computers, software, guidance and control, the separation events, and the performance of Orion’s critical heat shield. All of Orion’s avionics components were installed earlier this summer, and engineers with Lockheed Martin (Orion’s prime contractor) have completed functional testing on the crew module’s 59 systems— methodically powering them up one by one. Performance testing, where all of the systems work together to operate Orion as a whole, was completed last spring prior to installation of the capsule’s state-of-the-art ablative heat shield, which is outfitted with over 200 instrumentation sensors to provide engineers with data about the heat shield’s ability to protect Orion. A titanium skeleton and carbon-fiber skin gives the heat shield its shape, and will provide structural support during landing. www.RocketSTEM .org