Once ignited the five-segment SLS booster will deliver an incredible 3.6 million pounds of thrust, which is equivalent to 22 million horsepower—each—and the SLS will employ two of the 1.6 million pound boosters (1.4 million is propellant) to help NASA’s future deep-space crew missions escape the pull of Earth’s gravity to reach destinations such as an asteroid and, eventually, Mars. The five-segment SLS boosters will burn for the same amount of time as the old shuttle boosters—two minutes—but they will provide 30 percent more power.
For Wednesday’s QM-1 test fire more than 500 instrumentation channels will be used to help evaluate over 100 defined test objectives, some of which are as follows:
Analysis of instrumentation data and post-test hardware evaluation used to show compliance to objectives
Daily countdown test runs have been conducted for the past couple weeks to verify all systems are ready for Wednesday’s QM-1 test fire. According to company spokesperson Kay Anderson, the dry runs went very smoothly and served their purpose, which was to find any bugs or discrepancies and resolve them long before test day.
To help put the power of Orbital ATK’s five-segment SRB into perspective, consider this: If the heat energy of the booster could be converted to electric power, the two SRBs firing for two minutes would produce 2.3 million kilowatt hours of power, enough to supply the entire power demand of over 92,000 homes for a full day.
QM-1 will support qualification of the booster design for performance at the highest end of the motor’s accepted propellant temperature range, some 90 degrees Fahrenheit. In order for engineers to specifically assess this the booster has been housed for some time inside a 100 degree Fahrenheit movable structure, conditioning QM-1 daily in order to reach a propellant mean bulk temperature of 90 (+/- 5) degrees Fahrenheit.
The “test window” is available until 2:00 p.m. MDT (4:00 p.m. EDT); if they cannot fire the booster by that time they will stand down for crew rest requirements and try again March 12, assuming the delay was something minor that would not require an extended delay (of course, that cannot be determined until it happens).
Once the test is complete, a post-fire disassembly inspection will be conducted. It will take approximately six weeks to disassemble and remove the QM-1 booster from the test stand, and detailed inspections will take another several months.
A second, low-temperature test (QM-2) is planned for early 2016 before the hardware testing to support qualification of the boosters will be complete, at which point they will then be ready to proceed toward the first flight of SLS, currently scheduled to fly on the Exploration Mission-1 (EM-1) in late 2018.
Orbital ATK has set up public viewing areas for the test fire, so anyone wanting to witness it in person is welcome to make their way to Promontory, Utah, to see another big milestone on the road toward the first launch of NASA’s SLS.
QM-1 Static Test – One Step Closer to Flight
NASA’s Space Launch System (SLS) is one step closer to flight following Orbital ATK’s March 11 successful five-segment rocket motor qualification ground test. Immediately following the spectacular two-minute test, it appeared that everything went exactly as expected. More significant is that two months later, now that disassembly has begun and engineers have reviewed and analyzed miles of data, it is clear that the test was a resounding success.
NASA’s SLS will launch on its first mission, Exploration Mission-1, in just a few years, and in the future, the SLS vehicle, along with NASA’s Orion crew capsule, will take humans farther into space than ever before.
The ground test of Orbital ATK’s five-segment rocket motor, known as Qualification Motor-1 (QM-1), had 102 design objectives and was supported by more than 530 instrumentation channels. A key objective of QM-1 was to test the solid rocket motor performance at high temperature (90 degrees F mean bulk temperature). The motor’s nozzle and insulation performed as expected, ballistics performance parameters met requirements, and the thrust vector control and avionics system provided the required command and control of the motor nozzle position – exactly as planned.
“These test results, along with the many other milestones being achieved across the program, show SLS is on track to preserve our nation’s leadership in space exploration,” said Charlie Precourt, Vice President and General Manager of Orbital ATK’s Propulsion Systems Division, and four-time space shuttle astronaut.
Orbital ATK’s new five-segment boosters for SLS leverage a flight-proven four-segment design, while implementing technological and performance upgrades including: the addition of a fifth motor segment to provide increased power, an advanced avionics system, a more environmentally friendly motor insulation design, a safer flight termination system, and more efficient and modern processing techniques. These changes were designed to meet performance requirements and increase reliability, while lowering manufacturing costs.
This first test of the SLS qualification phase of testing (QM-1) was preceded by a robust three-test demonstration phase (DM-1, DM-2 and DM-3) that helped to substantiate motor design. The qualification phase will conclude with QM-2, scheduled for next spring, fully demonstrating the motor’s readiness for flight. QM-2 will test the motor performance at the lower temperature limit (40 degrees).
“Ground tests are very important – we strongly believe in testing before flight to ensure lessons-learned occur on the ground and not during a mission,” said Precourt. “With each test we have learned things that enable us to modify the configuration to best meet the needs for the upcoming first flight.”
The ground test of Orbital ATK’s five-segment rocket motor, known as QM-1, ocurred on March 11, 2015.
Orbital ATK technicians de-mated the QM-1 center forward segment from the forward segment as part of the qualification motor’s disassembly process.
Orbital ATK technician analyze the five-segment solid rocket motor following the March 11, 2015 QM-1 test.