If at first you don’t succeed… Orion successfully completes fairing separation test
A test article of NASA’s next manned spacecraft, the Orion Multi-Purpose Crew Vehicle, successfully completed a fairing separation test Wednesday, Sept. 6. A similar test was conducted in June of this year. Things did not go as planned. Only two of the three panels deployed fully. With a problem in front of them, NASA and Orion’s manufacturer, Lockheed-Martin set to the task of finding out why this happened.
The three panels, called fairings, each of which is 14 feet high and 13 feet wide – must separate for Orion to be able to achieve its mission objectives. They serve as a shield for the spacecraft during the tumultuous ride through Earth’s atmosphere. These fairings are different than those traditionally used as they will not only shield Orion – but support its weight as well. About half of the spacecraft’s weight in fact will be carried by the fairings.
Both the crew module as well as the Launch Abort System (LAS) will ride atop the fairings. It is believed that this system will improve performance as well as cut back on one of the chief concerns of aerospace engineers everywhere – weight.
While vital, the fairings don’t stay with Orion for very long, approximately just 560,000 feet up, they will be jettisoned. Their mission fulfilled, they will fall back to Earth.
For this to happen however, six “breakable” joints along with six explosive bolts need to perform as advertised. In a precise ballet of pyrotechnics, the joints and then the bolts fire followed by springs which push the panels away from the spacecraft, freeing Orion to conduct its mission. The bolts hold the fairing panels to the rocket as well as each other. With the June failure looming in their minds, engineers began to work to determine the root cause of why this failed to take place. This week’s test was conducted at Lockheed-Martin’s Sunnyvale, Calif., facility.
During this week’s test, it was discovered the June fairing malfunction was the result of the fairing coming into contact with the adapter ring. Thus when the bolts fired and the springs pushed the fairing away – the panel was caught by the ring – stopping it from functioning properly.
Engineers feel they have resolved the issue. They also worked to make the test more stressful, to better simulate the heat the panels will encounter on ascent. Testing the fairings as close to as possible to real world conditions should ensure fewer surprises come launch day. Using what is a NASA press release describes as “strip heaters” – one of the panels was exposed to temperatures of 200 degrees Fahrenheit.
The first mission for Orion will be the planned Exploration Flight Test 1 (EFT-1), planned to take place in Sept. 2014. In this case, the Orion flight test article will utilize the current largest rocket in the US arsenal, United Launch Alliance’s Delta IV Heavy. The launch will take place at Cape Canaveral Air Force Station’s Space Launch Complex 37 in Florida. This mission, very similar in many aspects to the Apollo 4 flight, will be conducted to test out the spacecraft’s heat shield, avionics and other systems.
During EFT-1, Orion will go further than any human-rated spacecraft has traveled in more than four decades, some 3,600 miles (15 times higher than where the International Space Station orbits). It will return to Earth at an estimated 20,000 miles per hour – providing the ultimate test of the heat shield which will be used to protect crew riding on the capsule-shaped vessel. Although Orion will only conduct two orbits – they will be critical to the spacecraft’s future.
Data gleaned from EFT-1 will serve to either validate systems – or to reveal flaws in the design. Good or bad, whatever the flight test article of Orion discovers – will be used to improve future models of the spacecraft.
“Hardware separation events like this are absolutely critical to the mission and some of the more complicated things we do,” said NASA’s Orion program manager Mark Geyer in a NASA news release detailing this week’s fairing test. “We want to know we’ve got the design exactly right and that it can be counted on in space before we ever launch.”
Orion, much like the Apollo spacecraft, is comprised of a command module (where the crew reside) and the service module. The service module is located underneath the command module and contains propulsion systems, attitude control as well support systems for the crew (power, water, thermal control and air).
The service module will travel with the command module until the point when the command module is ready to re-enter Earth’s atmosphere. As the EFT-1 Orion will fly without astronauts on board and will not need those systems which support crew, the service module for this flight will only be a test service module.
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.