Westover Air Reserve Base is an Air Force Reserve Command (AFRC) installation located in the Massachusetts communities of Chicopee and Ludlow, near the city of Springfield, Massachusetts. Westover hosts the largest Air Reserve Base in the world in terms of area. Until 2011, it was a backup landing site for the NASA Space Shuttle and in the past few years has expanded to include a growing civilian access airport sharing Westover's military-maintained runways. The installation was named for Major General Oscar Westover, commanding officer of the Army Air Corps in the 1930s, killed in the crash of his high-speed Northrop A-17AS, 36-349, c/n 289, in a crosswind short of the runway at Lockheed Aircraft's air field in Burbank, California, now known as Bob Hope Airport, on 21 September 1938. The host unit is the 439th Airlift Wing (439 AW) of the Twenty-Second Air Force (22 AF), Air Force Reserve Command. Outside of the AFRC command structure, the 439 AW and Westover are operationally gained by the Air Mobility Command (AMC).