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<\/p>\nThe first GEM-63XL motor for the ULA Vulcan Centaur\u2019s strap-on boosters was successfully test-fired for approximately 90 seconds, sending 449,000 lbs of thrust along with bright fire, loud noise and vibration into the sunny desert sky on Thursday at Northrop Grumman testing facility in Promontory, Utah.<\/p>\n
The QM-1 was the first of two test firings required before the GEM-63XL is used in operational missions on the new ULA Vulcan Centaur, which has recently won a number of critical US Space Force launches under the National Security Space Launch contract, and which will replace the long-serving Atlas V beginning with its scheduled first flight in 2021.<\/p>\n
The GEM-63XL fired today was conditioned to a temperature of 40 degrees Fahrenheit to test the motor\u2019s performance in cold conditions. Ballistic, insulation, nozzle plug, igniter insulator performance and ablative nozzle performance, erosion and plug measurements were taken with 192 instrumentation channels, and these were the main qualification objectives.<\/p>\n
Additional objectives included vibration, acoustic, and heat data, motor axial elongation and radiative heat monitoring data. The cold conditioned test was done first as it is the most taxing test of the motor and its systems, including the fixed, non-steerable nozzle.<\/p>\n
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The GEM-63XL ahead of its test \u2013 via NG<\/p>\n
The next test firing, VM-1, will be the validation motor and it will be hot-conditioned to a temperature of 90 degrees Fahrenheit. Its objective will be risk mitigation for the US Space Force by finishing a second test before the GEM-63XL flies.<\/p>\n
The GEM-63XL at 865 inches in length is longer than the GEM-63 qualified for flight one year ago, and the XL will use a pointed nosecone as opposed to the blunt curved nosecone that is currently used on the AJ-60A and that will be used on the GEM-63.<\/p>\n
The XL\u2019s nozzle exit cone diameter is 60 inches and its propellant mass is 105,497 lbs as opposed to a 58 in exit cone and 97,195 lb propellant mass for the GEM-63 tested previously. Also as Northrop Grumman Vice President of Propulsion Systems Charlie Precourt stated, \u201cThe GEM 63XL increases thrust and performance by 15-20 percent compared to a standard GEM 63.\u201d<\/p>\n<\/p>\n