Naval Surface Warfare Center Dahlgren Division (NSWCDD) engineers designed, developed and delivered an upgraded 105 mm air gun unit (GAU) made specifically with the U.S. Air Force AC-130 “gunship” in mind.
The 105mm GAU provides heavy firepower to the AC-130 to perform its close air support, air interdiction and friendly force protection missions. These aircraft are often seen operating alongside Special Forces units deployments on the ground.
The new weapon replaces the former gun system and positively impacts the warfighters’ ability to operate and maintain the system in the field.
“It has become a much more reliable system with less maintenance,” said Matthew Buckler, chief mechanical engineer for the NSWCDD Gun Weapon System (BMS). “If we can get a system that is more reliable, that is more repeatable, that performs and that allows the warfighter to complete their mission every time, that’s a huge benefit.”
From the beginning of the design, the Dahlgren engineers behind the new 105 mm gun worked directly with experienced gunners and technicians to get real-time feedback on their operational needs and experiences.
GAU project engineers traveled to Wright-Patterson, Robins, Eglin, Hurlburt Field and Cannon Air Force bases during development to conduct testing and collaborate directly with users. Gunners and technicians also came to Dahlgren to provide feedback on hardware performance after testing.
“Personally, this is the most rewarding job I’ve done in my engineering career, hands down,” said Gregory Fish, senior GAU analyst at NSWCDD. “It’s a fantastic place to work, with an incredible sense of accomplishment and fulfillment. And when we get the reports on the effectiveness of the weapon in the field, it makes you feel like you’ve done something that makes a difference because these [GAUs] are literally the tip of the spear.”
The previous iteration of the AC-130 105mm gun system consisted of the M102 howitzer and M137A1 recoil mechanism, which are no longer supported by the Army, meaning an upgrade was necessary due to obsolescence and technological advances since the original recoil mechanism was designed.
Upgrades to the 105mm GAU are extensive, but Dahlgren engineers have been careful to ensure that the weapon’s functionality, accuracy and ease of use remain virtually the same.
Throughout the iterative design process, Buckler said the team encountered challenging, but navigable, obstacles and addressed each problem as it arose.
“We described [the development process] as peeling an onion,” Buckler said. “You take the most immediate problem and solve that one. Then, when you solve it, there’s something more important and you keep peeling until you’ve solved all the major problems and you can live with whatever the maintenance interval is.”
