Northrop Grumman Corporation conducted its first full-scale static test fire of the Sentinel stage-one solid rocket motor at the company’s test facility in Promontory.
This development test will further prove the Sentinel team’s design approach and gain confidence to move to the next stage of testing. The motor fired for the anticipated duration and met performance parameters and objectives within expected ranges.
«This static fire highlights the advances we’ve made in digital engineering and gives us confidence in our ability to translate that into hardware build and test as we continue to make progress on the path to flight testing», said Sarah Willoughby, vice president, Sentinel, Northrop Grumman. «The results allow us to validate and anchor our stage-one motor performance before entering qualification testing and completing system analyses, key to lowering risk as we mature the Sentinel design and advance towards critical design review».
Northrop Grumman also leveraged advanced testing equipment that allowed for increased data collection to better understand motor characteristics.
«Our investments in digital design, test and advanced manufacturing help to ensure we develop this next-generation missile more affordably and with innovation at its core, delivering to the Air Force a safe, secure, reliable and flexible capability», added Willoughby.
The Sentinel intercontinental ballistic missile weapon system is the U.S. Air Force’s program to modernize the land-based leg of the strategic triad, replacing the Minuteman III system that has been in service for more than half a century.
The Sentinel missile features a three-stage booster, with Northrop Grumman producing stages one and two. The booster is a new design, using the latest materials and design technologies to ultimately improve performance, reliability, safety and sustainability.
Northrop Grumman Corporation successfully completed a series of wind tunnel tests of the LGM-35A Sentinel InterContinental Ballistic Missile (ICBM). Using scaled models of the vehicle, stressed under environments from sub to hypersonic speeds, the robust test campaign validated digital modeling and simulations and proved design maturity of the missile.
«This wind tunnel campaign is an opportunity to put our digitally engineered designs to the test, under conditions that mimic a missile launch», said Sarah Willoughby, vice president and program manager, Sentinel, Northrop Grumman. «Predictions from the modeling correlated with the testing results, giving us confidence in our model-based engineering approach. Data from these tests will inform future engineering decisions as we mature the design and continue on a path to deliver this critical capability to the Air Force».
Wind tunnel testing is a key early step in any missile development program because it determines how a vehicle will perform during flight. A team of engineers created seven comprehensive test campaigns, each with a unique set of requirements, to measure how the missile would respond to various atmospheric, load and speed conditions. Tests simulated everything from firing the missile, to stage separation and various flight maneuvers. The team is now updating models to enable full scale predictive environments for the development of Sentinel flight hardware.
«Tests were conducted at industry and government-run facilities across the U.S. in under a year», said Willoughby. «This is an extremely complex effort proving the value of digital engineering in helping us move to the next phase with certainty».
The U.S. Air Force’s Sentinel weapon system is a critical modernization of the current land-based leg of the U.S. nuclear triad, replacing the Minuteman III ICBM system that has been in service for more than 50 years. The program represents advancements in technology with the use of digital engineering, advanced tooling, and a modular, open-architecture approach.
The Department of the Air Force’s new weapon system, the Ground Based Strategic Deterrent, has officially been designated the LGM-35A Sentinel.
Secretary of the Air Force Frank Kendall approved the designation for the system that modernizes the InterContinental Ballistic Missile (ICBM) leg of the Nation’s nuclear triad.
«Our Nation’s nuclear deterrent force, two legs of which is operated by Airmen, has quietly provided a strategic security shield for decades», Kendall said. «All that time, the Department of the Air Force has kept the watch; always vigilant and ready. The name Sentinel recognizes the mindset that thousands of Airmen, past and present, have brought to the deterrence mission, and will serve as a reminder for those who operate, secure, and maintain this system in the future about the discipline and responsibility their duty entails».
The Air Force determined the LGM-35A Sentinel would provide continuity in strategic deterrence and cost less than extending the life of the current ICBM fleet, comprised of the aging Minuteman III. Replacing the 1970s-era missile modernizes the ground-based leg of the nuclear triad and brings the Minuteman’s more than 50 years of service to a close.
«As the Air Force celebrates its 75th anniversary this year, the Minuteman III Weapon System has been and will continue to be integral to our Nation’s defense», said Air Force Chief of Staff General Charles Q. Brown, Jr. «As we look ahead to the next 75 years, investing in nuclear modernization is as relevant as ever and we are committed to transitioning to the Sentinel, which will ensure our Nation is ready to provide strategic deterrence for tomorrow».