Patuxent River Naval Air Station (NHK)

Patuxent River Naval Air Station, also known as NAS Pax River, is a U.S. Navy air station in St. Mary's County, Maryland, on the Chesapeake Bay near the mouth of the Patuxent River. The installation serves as a center for naval aviation test, evaluation and systems acquisition, and is home to Naval Air Systems Command headquarters, the U.S. Naval Test Pilot School and the Atlantic Test Range.

The airfield was commissioned on April 1, 1943, and its airfield, Trapnell Field, was named in 1976 after pioneering aviator VADM Frederick M. Trapnell. The station operates three runways, including the 11,799-foot runway 6/24, supporting military, government and test operations rather than scheduled commercial passenger service.

Located at the confluence of the Patuxent River and the Chesapeake Bay on the Cedar Point peninsula, the air station is adjacent to Lexington Park and roughly 60 miles (about 100 km) southeast of Washington, D.C. Road access is via Route 235 (Three Notch Road), with the drive from the capital typically taking around 1.5 hours depending on traffic.

As an active military installation, access is restricted to authorized personnel and visitors, and visiting aircraft require prior permission. On-base lodging and support facilities serve personnel, families and official travelers arriving through the airfield.