Sikorsky Aircraft Corp., a Lockheed Martin company, Stratford, Connecticut, is awarded a $550,372,323 modification (P00043) to previously awarded fixed-price-incentive (firm target), firm-fixed-price contract N00019-16-C-0048.  This modification is for Lot IV low rate initial production and delivery of six CH-53K aircraft and associated aircraft, programmatic and logistics support, rate tooling and physical configuration audits.  Work will be performed in Stratford, Connecticut (33.17%); Wichita, Kansas (11.51%); Salt Lake City, Utah (7.18%); Hazelwood, Missouri (6.28%); Bridgeport, West Virginia (3.22%); Redmond, Washington (2.12%); Windsor Lock, Connecticut (1.84%); Kent, Washington (1.54%); Fort Worth, Texas (1.44%); Quebec, Canada (1.35%); Cudahy, Wisconsin (1.29%); Rochester, United Kingdom (1.27%); Fort Walton Beach, Florida (1.11%); various locations within the continental U.S. (24.68%); and various locations outside the continental U.S. (2%), and is expected to be completed in July 2024.  Fiscal 2020 aircraft procurement (Navy) funds in the amount of $519,899,846; and fiscal 2021 aircraft procurement (Navy) funds in the amount of $30,472,477 will be obligated at time of award, none of which will expire at the end of the current fiscal year.  The Naval Air Systems Command, Patuxent River, Maryland, is the contracting activity.