AC-47 Spooky

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AC-47 Spooky

An AC-47 on the ground at Udorn Royal Thai Air Force Base, June 1970.

Type Fixed-wing gunship
Manufacturer Douglas Aircraft Company
Introduced 1965
Status In service in Colombia
Primary users United States Air Force
Vietnam Air Force
Royal Lao Air Force
Colombian Air Force
Developed from C-47 Skytrain

The Douglas AC-47 Spooky was the first in a series of gunships developed by the United States Air Force during the Vietnam War. It was felt that more firepower than could be provided by light and medium attack aircraft was needed in some situations when ground forces called for close air support.

Contents

[edit] Design and development

The AC-47 was a United States Air Force C-47 Skytrain (the military version of the DC-3) that had been modified by mounting three 7.62 mm General Electric miniguns to fire through two rear window openings and the side cargo door, all on the left (pilot's) side of the aircraft. Other armament configurations could also be found on similar C-47 based aircraft around the world. The guns were actuated by a control on the pilot's yoke, where he could control the guns either individually or together, though gunners were also among the crew to assist with gun failures and similar issues. Its primary function was for close air support for ground troops, both U.S. and South Vietnamese. Once called into action, it could loiter, orbiting the designated target, sometimes for hours, providing suppressing fire. Coverage given by a Spooky was over an elliptical area approximately 52 yards in diameter, placing a projectile within every 2.4 yards during a 3 second burst.[1]

Moreover, the plane carried 24,000 rounds of ammunition. Its high ammunition supply meant the AC-47 was highly unpopular with those on the receiving end of its fire, and extremely popular with the troops it supported (who nicknamed it Puff the Magic Dragon; there was even penned a version of the popular tune dedicated to the gunship). In addition to the miniguns, it also carried flares, which it could drop at will to light up the battleground.

AC-47
AC-47

Due to the age of its base airframe, the aircraft was very vulnerable to ground fire. Consequently, further gunship designs, the AC-119 gunship and the AC-130 gunship were developed, based around newer cargo airframes.

When the AC-47 was introduced, it was the first of its kind in and there were no preceding designs to gauge how successful the concept would be. When requests for additional gunships began to come in, the USAF found itself in a precarious situation. It simply did not have enough miniguns initially to fit additional aircraft after the first two conversions. The next four aircraft were in fact equipped with 10 AN/M2 .30 caliber (7.62 mm) machine guns. However, it was quickly found that these weapons, using ammunition stocks from WWII and Korea jammed easily, were extremely dirty in terms of gases produced from firing, and 10 guns could only provide the density of fire of a single minigun. When additional miniguns arrived, all four of these aircraft were retrofitted with to the standard armament configuration.

The mounting hardware initially used on the AC-47 simply used SUU-11/A gun pods that were installed on locally fabricated mounts for the gunship application. Eventually, Emerson Electric developed the MXU-470/A, a purpose built mount, which replaced the gun pods, and was also used on subsequent gunship aircraft.

[edit] Operational history

AC-47 at Nha Trang Air Base in South Vietnam
AC-47 at Nha Trang Air Base in South Vietnam

The AC-47D gunship should not be confused with a small number of C-47s were fitted with electronic equipment the 1950s. Prior to 1962, these aircraft were designated AC-47D. When a new designation system was adopted in 1962, these became EC-47Ds. In August 1964 years of fixed wing gunship experimentation reached a new peak with the intiation Project Tailchaser. This test involved the conversion of a single Convair C-131B to be able to fire a single GAU-2/A Minigun at downward angle out of the left side of the aircraft. It was discovered that even using crude grease pencil crosshairs it was very easy for a pilot flying in a pylon turn to hit a stationary area target with relative accuracy. Testing was conducted at Eglin AFB by ADTC.

By October, a C-47D under Project Gunship was converted to a similar standard as the Project Tailchaser aircraft, but instead with a total of 3 Miniguns. These were initially mounted on locally fabricated mounts, which essentially strapped gun pods intended for fixed wing aircraft (SUU-11/A) onto a mount allowing them to be fired remotely out the port side. This aircraft was sent for use by the 4th Air Commando in the Republic of Vietnam for operational testing. By mid-1965, a total of 6 aircraft were operating with the 4th Air Commando, and by fall of 1965, there were 20 more. The original gunships had been designated FC-47D by the United States Air Force, but with protests from fighter pilots, this designation was changed to AC-47D during 1965. Eventually the 4th Air Commando was absorbed into the 14th Special Operations Wing (SOW), and AC-47Ds were assigned to the 3rd and 4th Special Operations Squadrons (SOS), as well as, later to the 432nd Tactical Fighter Wing (TFW) at Udorn Royal Thai Air Force Base. By war's end, the USAF lost 19 AC-47 Gunship I's, to all causes.[2]

MXU-470/A Minigun modules in an AC-47.
MXU-470/A Minigun modules in an AC-47.

As the United States began Project Gunship II and Project Gunship III, many of the remaining AC-47Ds were transferred to the Vietnam Air Force (VNAF), the Royal Lao Air Force (RLAF), and to Cambodia, after Prince Sihanouk was deposed in a coup by General Lon Nol.

John L. Levitow was an AC-47 loadmaster on the February 24, 1969 mission that earned him the Medal of Honor.

Retrofitted AC-47s are still in use in Colombia, where they are known by civilians as Avion fantasma (ghost planes). They are successfully operated by the local airforce in COIN operations in conjunction with AH-60 Arpia helicopters (an armed variant of the UH-60) and A-37 Dragonflys against local illegal armed groups. These are mostly likely the five BT-67s purchased by Colombia with 12.7mm machine guns (of unknown type) slaved to a Forward Looking Infrared (or FLIR) system. For more information see Colombia: Seguridad & Defensa. The BT-67 is a variant of the C-47/DC-3 made by the Basler Corporation of Oshkosh, WI. These "Turbo Dakotas" feature Pratt & Whitney Canada PT6A-67R turboprops, driving five-bladed Hartzell propellers, along with essentially overhauling the basic airframe.

Variants of the AC-47 based on various iterations of the airframe including the BT-67, have been used by Laos, Cambodia, South Africa, and Rhodesia, to name just a few, and with a variety of weapons configurations including gatling weapons of numerous types, various medium and heavy machine guns, and larger autocannon (South African "Dragon Daks" were known to fit 20 mm cannons).

[edit] Operators

[edit] Current Operators

Flag of Colombia Colombia
Flag of El Salvador El Salvador
Flag of Thailand Thailand

[edit] Former Operators

Flag of Cambodia Cambodia
Flag of Laos Laos
Flag of Rhodesia Rhodesia
Flag of South Africa South Africa
Flag of South Vietnam South Vietnam
Flag of the United States United States

[edit] Specifications (AC-47)

General characteristics

  • Crew: 8: pilot, copilot, navigator, flight engineer, loadmaster, 2 gunners and a South Vietnamese observer
  • Length: 64 ft 5 in (19.6 m)
  • Wingspan: 95 ft 0 in (28.9 m)
  • Height: 16 ft 11 in (5.2 m)
  • Wing area: 987 ft² (91.7 m²)
  • Empty weight: 18,080 lb (8,200 kg)
  • Loaded weight: 33,000 lb (14,900 kg)
  • Max takeoff weight: lb (kg)
  • Powerplant:Pratt & Whitney R-1830 radial engines, 1,200 hp (895 kW) each

Performance

Armament

  • Guns:
    • 3× 7.62 mm (0.30 in) General Electric GAU-2/M134 miniguns, 2,000 rounds/gun or
    • 10× .30 in Browning AN/M2 machine guns
  • 48× Mk 24 flares

[edit] References

  1. ^ AC-47D factsheet from the National Museum of the USAF. Each minigun fired at a rate of 6000 rounds per minute. This provided coverage over an elliptical area approximately 52 yards in diameter, placing a projectile within every 2.4 yards during a 3 second burst.
  2. ^ Hobson, Chris. Vietnam Air Losses, USAF/USN/USMC, Fixed-Wing Aircraft Losses in Southeast Asia 1961-1973. 2001. ISBN 1-85780-1156

[edit] External links

[edit] See also

Related development

Comparable aircraft

Related lists