Coincidental with the increased US involvement in Southeast Asia, the USAF had been experimenting with the concept of side-firing fixed-wing gunships as a means of providing heavy fire support in low-threat environments.  Following successful trials at Eglin AFB with a modified Convair C-131 in 1963 and 1964 the USAF modified two of the 1st ACS’s C-47s at Bien Hoa in December 1964 to gunship standard as an operational trial.  The fixed-wing gunship concept involved the aircraft maintaining a constant banked turn about 3,000 feet above the target.  Firepower was provided by three 7.62mm Gatling-type guns firing through the side windows.  As it was envisaged that the C-47’s size and performance would limit its use primarily to night operations, each aircraft carried an ample supply of flares with which to illuminate the target.  The system was ideal for the protection of isolated outposts and camps that were increasingly coming under Viet Cong attack at night.

The trial in South Vietnam proved the potential of the gunship concept and further aircraft were modified in the USA.  The 4th ACS arrived at Tan Son Nhut on 14 November 1965 with 20 gunships and had flown 277 operational sorties by the end of the year.  Initially designated the FC-47, the gunships were soon redesignated as the AC-47D and were quickly nicknamed Puff the Magic Dragon or simply Dragonship due to their apparent fire-breathing capability as they spat out thousands of rounds of tracer.  To the crews who flew them, the aircraft also became known as Spooky, after the Squadron’s radio call sign.  Once established at Tan Son Nhut the Squadron deployed flights of four aircraft to Da Nang, Pleiku, Nha Trang and Bin Thuy to provide gunship support throughout the country.  Twelve of the 47 AC-47s sent to Southeast Asia would be lost during the war.