The squadron was first organized in England during World War II, moving to North Africa shortly after the invasion.

In the mid-1950s, its home station proved too small to accommodate jet fighters, so its role changed to airlift and it became the 140th Air Transport Squadron.

It was initially part of to VIII Fighter Command, equipped with a mixture of United States personnel reassigned from the 31st and 52d Fighter Groups, and Americans transferred from the Royal Air Force (RAF) who had volunteered to join the RAF prior to the United States entry into the European War.

The squadron deployed to French Morocco and became part of Twelfth Air Force where the unit engaged in combat during the North African Campaign.

Each squadron of the 350th Fighter Group was assigned two P-38s to intercept and destroy high flying Luftwaffe reconnaissance aircraft sent to photograph the allied invasion fleet gathering along the North African coast for the Operation Husky, the invasion of Sicily.

It also covered Allied landings on Elba in June 1944 and supported the invasion of southern France in August.

In September the squadron upgraded to jet propelled and air intercept radar equipped Lockheed F-94 Starfire aircraft.

[1] However, ADC was experiencing difficulty under the existing wing base organizational structure in deploying its fighter squadrons to best advantage.

On 1 November 1952 the 148th was returned to the control of the State of Pennsylvania[1] and its personnel, equipment and mission were transferred to the 46th Fighter-Interceptor Squadron, which was simultaneously activated at Dover.

However, the National Guard Bureau's and the Commonwealth of Pennsylvania's desire to retain the unit brought a new mission and a numeric designation to the organization, the squadron was redesignated the 140th Air Transport Squadron on 1 July 1956 using propeller-driven Curtiss C-46 Commando aircraft.

In 1961, the squadron moved to Olmsted Air Force Base, assuming an aeromedical evacuation mission and converted to Lockheed C-121 Constellations.

These units were located at Olmsted Air Force Base and operated the Lockheed C-121 Constellation.

Threatened by the closure of Olmsted (now Harrisburg Air National Guard Base) and by the downsizing of all conventionally powered transport aircraft, the National Guard Bureau volunteered the unit for a psychological warfare capability named "Coronet Solo" in 1967.