Naval Air Station Joint Reserve Base Fort Worth (abbreviated NAS JRB Fort Worth) (IATA: FWH, ICAO: KNFW, FAA LID: NFW) includes Carswell Field, a military airbase located 5 nautical miles (9 km; 6 mi) west of the central business district of Fort Worth, in Tarrant County, Texas, United States. This military airfield is operated by the United States Navy Reserve. It is located in the cities of Fort Worth, Westworth Village, and White Settlement in the western part of the Fort Worth urban area.

NAS Fort Worth JRB is the successor to the former Naval Air Station Dallas and incorporates other Reserve commands and activities, primarily those of the Air Force Reserve, that were present on site when the installation was known as Carswell Air Force Base, a former Strategic Air Command (SAC) facility later transferred to the Air Combat Command (ACC).

Several United States Navy headquarters and operational units are based at NAS Fort Worth JRB, including Naval Air Reserve air wings and aviation squadrons, intelligence commands and Seabees.

The Air Force Reserve Command's Tenth Air Force (10 AF) headquarters and the 301st Fighter Wing and its flying squadron the 457th Fighter Squadron continue to be based at the installation. The Wing is currently (2024) converting to the F-35 Lightning II after operating the F-16 for 32 years. The 136th Airlift Wing of the Texas Air National Guard and its flying component, the 181st Airlift Squadron, fly new stretch versions of the C-130J airlifter. MAG-41, a Marine Aircraft Group, with VMFA-112 (F-18C), VMGR-234 (KC-130J), VMR-1 (C-40A), and various ground units are also located at NAS Fort Worth JRB. VR-59 flies the C-40A personnel and cargo transport.

Aircraft types initially based at NAS Fort Worth JRB were the F-14 Tomcat, F/A-18 Hornet, C-9B Skytrain II, C-130 Hercules and KC-130 Hercules that relocated from the former NAS Dallas, joining extant F-16 Fighting Falcon aircraft that were previously located at the installation while it was known as Carswell Air Force Base and later as Carswell Air Reserve Station.

Currently based aircraft are Navy C-40 Clipper transports of the Naval Air Reserve, Air Force F-16 Fighting Falcon fighters of the Air Force Reserve Command, C-130 Hercules airlift aircraft of the Texas Air National Guard, Marine Corps F/A-18 Hornet strike fighters and KC-130 Hercules aerial refueling and transport aircraft of the Marine Corps Reserve. The U.S. Army Reserve also has D Co, 6/52AVN flying UC-35 and C-12 aircraft on VIP transportation duties.

Carswell Air Force Base was named after Medal of Honor recipient Major Horace S. Carswell, Jr., USAAF (1916–1944). Major Carswell was returning from an attack on Japanese shipping in the South China Sea on 26 October 1944 when he attempted to save a crewmember whose parachute had been destroyed by flak. He remained at the controls of his crippled bomber and died while crash-landing the B-24 Liberator near Tungchen, China. The base was renamed in his honor on 29 January 1948.

Carswell's origins date back to the early years of aviation. After the United States' entry into World War I in April 1917, General John J. "Blackjack" Pershing invited the British Royal Flying Corps (RFC) to establish training fields in the southern United States where the warmer weather would be more conducive for flying year-round. In June, the War Department inspected 6 sites around Fort Worth, Texas which had been offered by the Chamber of Commerce. In August the War Department signed leases with the RFC on 3 sites around Fort Worth. Knows as the Flying Triangle, these sites were Hicks Field (#1), Barron Field (#2), and Benbrook (later Carruthers) Field (#3) based on their locations. In April 1918 these airfield were turned over to the Air Service, United States Army as training fields for American pilots. Hundreds of pilots learned their basic and primary flying skills at these airfields in the Fort Worth area during the war. They were closed in 1919 when the war ended.