A U.S. Army UH-60L Black Hawk in flight in Afghanistan in 2013.
Sikorsky is upgrading the U.S. military's fleet of UH-60 Black Hawks to fight corrosion, increase the number of available flight days for the rotorcraft in Afghanistan and other deployed areas, and reduce operations and maintenance costs.
"We’ve transitioned from many sheet metal components to high-speed machined components for the air frame," Chris Dowse, Sikorsky's director of Army programs, wrote in an email to R&WI. "Benefits of this adjustment include the elimination of mating surfaces prone to crevice corrosion, the elimination of holes prone to corrosion, and the elimination of air frame structure/dissimilar fastener locations prone to galvanic corrosion. We’ve also adopted the use of polyurethane gel floor tape, which has shown a significant improvement in corrosion performance; and the use of conductive polyurethane gel antenna gaskets. The result is reduced maintenance and extended inspection intervals."
Sikorsky and the Army have worked on a number of other UH-60 anti-corrosion upgrades, including improvements to the main gear box housing to reduce the number of "water trapping" pockets, according to an Army briefing in November 2017.
The DoD Corrosion Policy and Oversight Office said in an FY 2018 update report last year that the Army's 806 UH-60Ls were responsible for nearly $244 million in corrosion costs in FY 2016 and that the UH-60L has been among the top 10 helicopters contributing to average Army corrosion costs in the last decade of reports by the office.
Leading efforts to impede corrosion on military helicopters, such as the Black Hawks, will be a topic discussed at the Defense Strategies Institute Military Aviation Systems Summit on Jan. 16-17 in Tampa.
The DoD Corrosion Policy and Oversight Office said in its report last year that corrosion on Navy and Marine Corps' helicopters represented a "worrisome trend."
"The number of corrosion-related NADs (non-available days) has been increasing every year since FY 2010 and increased significantly in FY 2016," the report said. The three Navy/Marine Corps helicopters with the highest total corrosion costs in FY 2016 were the MV-22B, the MH-60R, and the MH-60S. Corrosion costs for those rotorcraft were more than $850 million in FY 2016.