USAF airman redesigns cargo door bracket with 3D printer Metal Tech News Weekly Edition – June 17, 2020
U.S. Air Force Airman Technical Sergeant Ryan McBride, who is the sheet metal production lead of the 19th Maintenance Squadron, in collaboration with the Air Force Life Cycle Management Center are utilizing metal 3D printing to create stronger and less expensive brackets for Hercules C-130 fleets.
Currently stationed at the Little Rock Air Force Base, McBride is the noncommissioned officer in-charge of metals technology.
During his time working on C-130Js, McBride found himself and his team needing to manufacture and replace a seemingly unremarkable, yet crucial bracket at unreasonable rates.
This bracket is designed to hold the C-130J's manual hydraulic pump, a device that allows for the lowering and raising of the ramp with a hand pump when the aircraft is powered off or if the hydraulic system fails. Lowering the ramp with this hand pump, however, puts immense force on the brackets.
"With its current design, the bracket can withstand very minimal side loading from the pump handle. Because of this, an estimated 30 to 40 brackets break per year and must be locally manufactured, which is a very difficult and time-consuming process," 1st Lt. Jesse Montgomery, Air Force Life Cycle Management Center C-130 structures engineer explained.
McBride had an idea to use metal 3D printing to make a stronger bracket at a fraction of the cost. His concept came to fruition earlier this month when the bracket became one of the first 3D printed metal parts to be installed on a C-130J.
"Lab testing has shown the new 3D printed part can withstand three times the downward force and 10 times the side force compared to the original bracket, making it much less likely to break in the field," said Montgomery. "The 3D printed version also costs an estimated $3,800 less per part to make and requires significantly fewer man-hours to produce. It also showcases the power of 3D printing in using complex geometry to improve strength and reduce costs, which would not be possible using traditional manufacturing."
With a cargo compartment approximately 41 feet long, nine feet tall and 10 feet wide, and a capacity for up to 92 troops, 64 paratroops, 74 littered patients or 45,000 pounds of cargo, there is a reason why the Hercules line has the longest continuous production run of any military aircraft in history.
Despite the stringent checks an aircraft must pass, let alone a military aircraft like the Hercules, the seldom used but necessary brackets would break from the force of the heavy rear hold door.
"3D printing the bracket will make it easier for C-130J maintenance units across the Air Force to obtain the part and eliminate the need to manufacture it themselves," said McBride. "Pending successful field testing, the bracket can be mass produced for the supply chain. Once approved, we will be able to order already printed parts that are ready for installation."
"As 3D printing becomes more prevalent, it has the potential to become more commonplace for engineering and manufacturing aircraft parts at a cheaper and more efficient rate. This introduces people to the benefits of 3D printing aircraft parts," he added. "This is just the beginning. It's still fairly new technology, but it's becoming much more readily available."
The Air Force is seemingly going all in with this burgeoning technology.
3D printed replacement latrine covers are already being produced for the C-5M Super Galaxy, a much larger jumbo jet by Lockheed Martin, at the Travis Air Force Base in California
The Air Force and Space Force are also collaborating on potentially 3D printing satellite parts.
While presently, the Air Force Life Cycle Management Center (LCMC) is limiting efforts to certify 3D printed aircraft parts to those that are not "flight critical", as the technology grows one can only imagine the shift towards massive industrialized 3D printing manufacturing becoming a possible future for military and private manufacturing alike.