Orion Spacecraft Cool Under Pressure
The Orion spacecraft at NASA’s Kennedy Space Center in Florida, has undergone extensive testing to prepare it for its first flight, currently scheduled to take place in September of next year. Tests to address new issues, as well as resolve old ones, have been taking place over the course of the past three weeks.
Last November, Orion’s rear bulkhead cracked when the capsule was pressurized. NASA has gone back and reinforced these sections and re-tested Orion, which passed muster on Wednesday, June 5.
Brackets were designed to strengthen the sections that failed during the previous pressure tests. The loads and stresses that contributed to the failures are now spread out.
NASA took the better part of a month to amend the issue, which a NASA release deemed “superficial.”
The Orion spacecraft that will fly the upcoming EFT-1 mission rests in the static loads test fixture at NASA’s Kennedy Space Center in Florida. Photo Credit: Kim Shiflett / NASA
As with most machines destined to take to the skies, engineers made sure that the spacecraft was tested to see if it could withstand stresses much stronger than expected. As the technicians checked out Orion, they cranked up the pressure to 110 percent of what it is expected to encounter in space. Orion handled these loads successfully.
“The static loads campaign is our best method of testing to verify what works on paper will work in space,” said Charlie Lundquist, NASA’s Orion crew and service module manager. “This is how we validate our design.”
These tests were conducted in a structure dubbed the static loads test fixture. Some 20 feet tall, the stand is used by engineers to validate the spacecraft’s design. The stand is equipped with hydraulic cylinders that press and tug at Orion to simulate the pressures it will encounter when it travels into the black. All total, Orion had eight different types of stresses placed on it that the spacecraft is expected to encounter on its mission. According to NASA, the stand has more than 1,000 gauges used to monitor how Orion handled the loads, which ranged anywhere between 1,000 to 240,000 pounds.
While this test addressed a problem that Orion had encountered in the road to launch, engineers at KSC have also moved forward with other tests required before Orion can be launched.
From May 13-27, Lockheed-Martin, the prime contractor on Orion conducted pyrotechnic bolt tests. “Pyro bolts” are explosive fixtures meant to separate Orion from the Launch Abort System or “LAS.” The LAS is a vital safety component used to propel astronauts away from Orion in the case of a failure on ascent. During these tests engineers individually tested five breakable bolts to ensure they would work.
“The purpose of the test was to reduce the shock levels on Orion when the launch abort system is jettisoned,” said Lockheed-Martin’s John Blair. “Several different materials and detonation device designs were tested on the GTA, providing data that will be evaluated to choose the best design for Exploration Flight Test-1.”
NASA plans to launch Orion atop a United Launch Alliance Delta IV Heavy rocket from Cape Canaveral Air Force Station’s Space Launch Complex 37. Orion will travel unmanned approximately 3,600 miles into space. When it returns to Earth, it will be traveling at about 25,000 mph. In so doing, Orion will validate Orion’s heat shield. The verification of this key component is just one of several that will be tested during this important test flight.
EFT-1 will serve as a shake-down cruise of Orion’s design. How well it handles launch, the space environment, reentry, the deployment of parachutes as well as other loads and stresses on the spacecraft’s frame will be tested under real world conditions.