Naval Air Station Joint Reserve Base Willow Grove

Naval Air Station Joint Reserve Base Willow Grove or NASJRB Willow Grove was a Naval Air Station owned by the U.S. Navy and located in Horsham Township, Montgomery County, Pennsylvania, United States  four miles (6 km) northwest of the central business district of Willow Grove, which is north of Philadelphia, Pennsylvania. The installation was transferred to the Pennsylvania Air National Guard and the name changed to the Horsham Air Guard Station after the U.S. Navy departed in 2011.

History
Flight activity began here in 1926 when Harold Frederick Pitcairn constructed a hangar and a grass airstrip in Horsham, Pennsylvania. The name "Willow Grove" came from the nearest town. At the time, Horsham was a rural township with little significance. From 1926 to 1942 Pitcairn used the airfield for design, construction and testing of a number of aircraft, including the Mailwing which was used by the United States Postal Service.

After the start of World War II, the United States purchased the grounds, and launched a classified anti-submarine warfare program at the base. Following WWII and into the Cold War, it became an operational and training base for aviation activities of the Naval Reserve, Marine Corps Reserve, Air Force Reserve, Air National Guard, Army Reserve and Army National Guard. As part of its joint recruitment efforts, the base was an annual host to one of the largest air shows on the East Coast until 2006.

Units
Horsham ANGS is home to the following:
 * 111th Fighter Wing (111 FW), Pennsylvania Air National Guard. The 111 FW no longer operates the A-10 Thunderbolt II and is slated to acquire ground control stations to remotely fly the MQ-9 Reaper.   The 111th functions as the host wing for the installation.
 * 270th Engineering Installation Squadron (270 EIS), Pennsylvania Air National Guard
 * The Liberty Bell Squadron of the United States Naval Sea Cadet Corps
 * Group 3 Headquarters of Pennsylvania Wing Civil Air Patrol.

The former NAS JRB Willow Grove was most recently home to the following military aviation units:
 * Marine Aircraft Group 49 headquarters and HMH-772 of the Marine Air Reserve's 4th Marine Aircraft Wing, the latter operating the CH-53E Super Stallion. Both MAG-49 and HMH-772 relocated to Joint Base McGuire-Dix-Lakehurst in 2011.
 * Fleet Logistic Squadrons 52 (VR-52) and 64 (VR-64) of the Naval Air Reserve, operating the C-9 Skytrain II and C-130T Hercules, respectively. Both VR-52 and VR-64 relocated to Joint Base McGuire-Dix-Lakehurst in March 2011.
 * 913th Airlift Wing (913 AW) of the Air Force Reserve Command. The 913 AW was inactivated by BRAC action on 30 September 2007.

Base Realignment and ClosHAH
On May 28, 2005, the Base Realignment and Closure commission recommended that NAS JRB Willow Grove be closed as part of the 2005 BRAC round, that the tenant Air Force Reserve Command airlift wing be inactivated and that Navy Reserve and Marine Corps Reserve flying units relocate to McGuire Air Force Base in New Jersey as tenant units.

On September 30, 2007, pursuant to direction of BRAC 2005, the Air Force Reserve Command disestablished the 913th Airlift Wing at the collocated Willow Grove ARS, redistributing its C-130 Hercules aircraft to other active duty Air Force and Air Force Reserve units.

On February 29, 2008, the Commonwealth of Pennsylvania released a report detailing a plan for a joint interagency installation (JII), with a mission of national defense, homeland security and emergency preparedness. However, on November 13, 2009, Pennsylvania dropped the plan for the JII based on the gradual removal of the 111th Fighter Wing. Future plans for the base include using a portion for the National Guard and other Reserve Component military personnel.

The airfield shut down on March 31, 2011; VP-64, VR-52, and a C-12 detachment were transferred to McGuire Air Force Base.

Currently, the 111th Fighter Wing, operating the A-10 Thunderbolt II, has lost all its aircraft to other ANG Squadrons under BRAC; the unit will take on a new role (so far undecided) in the near future. The unit will no longer operate aircraft.

Final closure of NAS JRB Willow Grove occurred on September 15, 2011. The Pennsylvania Air National Guard is expected to take custody, and the facility will be designated Willow Grove Air National Guard Base. A handful of National Guard and Army Reserve soldiers will remain, and the Air Force will maintain administrative offices on the property. The surplus land containing the runways will be turned over to Horsham Township for redevelopment; Horsham and other adjoining townships in Montgomery and Bucks Counties are currently debating the nature of this redevelopment.