Puff the Magic Dragon
(AC-47 and AC-130)
Aircraft equipped with special rapid-fire guns did not see action in Vietnam until after us "Early War" guys left. Development of a fixed-wing aircraft with side-firing weapons began in December 1962, called "Project Tailchaser." After experimenting and testing with several planes equipped with various types and sizes of guns... in the advanced "Project Gunship I," the cargo plane, C-47, was chosen. First it was tagged FC-47 (Fighter/Cargo-47), but fighter pilots railed against such a designation on a rusty old C-47, no matter what type of weapons it carried. The C-47 became AC-47 (Attack/Cargo-47). It was equipped with three side-mounted, General Electric SUU-11A/A Gatling-type Miniguns that fired 7.62mm rounds. The purpose was for it to be a "target suppressor," circling a target and laying down massive fire to eliminate or at least subdue the enemy position - an anti-personnel weapon.
AC-47 - flares lighting the night and fire from its side.
Minigun SUU-11A/A out cargo door of an AC-47.
Miniguns are really just souped-up rotating, multi-barreled Gatling Guns, like the one patented and produced by Richard J. Gatling in 1862. But these Gatling Guns didn't have hand cranks - they were usually powered by electric, but also had pneumatic or hydraulic external power sources. Rotating-barrel cannons were powered by the gas pressure or recoil energy of fired cartridges. The two miniguns sited here are the SUU-11A/A and the MXU-470/A - both were made by GE, and both fired 7.62mm rounds. They were electric motor-driven beasts.
Miniguns - the original SUU-11A/A and replacement MXU-470/A.
The equipped AC-47 left for Southeast Asia for trials and was in combat by December, 1964. Thus, the AC-47 became known as the original gunship. Five went through the original testing, and later, twenty more, in immaculate brown and green camouflage paint, arrived to strengthen the force. Improvements and modifications were made, including a new minigun system, the MXU-470/A. It was a simplified one-ended linkless-feed drum that was vertical, with the minigun mounted horizontally on top of the drum so that it was just the right height to fire out the windows of the AC-47.
Three Miniguns, MXU-470/A, in an AC-47.
Closeup of a MXU-470/A out AC-47 window.
The AC-47 was an extraordinarily simple aircraft to operate, and it also had no fire control computers, or infra-red devices, not even a night observation sight. The only fire control devices on board were: 1) A good pair of eyes; 2) A quick mind to calculate the correct amount of "Kentucky Windage"; and, 3) A steady pair of sweaty palms. After locating the target, the pilot must mentally compute the "slant range" - the distance between the gun muzzle and the target. This slant range is what determined the amount of bank the aircraft needed to bring the guns on target. Other variables to consider included: 1) Airspeed - Each knot of wind will displace the projectile 1.69 feet per second of bullet travel; 2) Gun Recoil - As the guns are fired it causes the aft fuselage to swing to the right, which cause the bullets to fall short and to the rear of the target; and, 3) Saturation Factor - How many bullets in a prescribed target area. (Example - a four-second burst from one minigun, at a slant range of 4500 feet, will put 400 bullets in a circle 31.5 feet in diameter.)
Crew loading for next run - notice the three gun barrels.
The AC-47s used the call sign "Spooky" (a ghost coming out of the night), but were commonly referred to as "Puff" (as in "Puff the Magic Dragon"). The name traces back to one of the first missions, when the three miniguns were loaded with all tracer ammunition. South Vietnamese troops were panic-stricken by the tongues of fire they saw licking over the ground after Viet Cong. All they could see was a steady stream of tracers raining down from the sky and heard the eerie growl of the guns reverberating from the open cargo bay. Calling the plane a dragon, the troops were virtually on the point of breaking and running. Their U. S. Advisers calmed them with assurances that the dragon was friendly, but magic. It was a fire-breathing dragon with an extreme hail of fire during night missions, and thus, the Dragonship. The Vietnamese, being a superstitious people, took the name literally. Captured VC documents later told of orders not to attack the dragon as weapons are useless and it will only infuriate the monster.
The "Dragon's Breath" from an AC-47
The "Dragon's Teeth" - Three MXU-470/A.
Puff worked mostly at night and did not come up against gunners willing to face her murderous fire. Each of the three miniguns could selectively fire either 50 or 100 rounds per second. Cruising in an overhead orbit, making banked pylon-turns, at 120 knots at an altitude of 3,000 feet, the AC-47 could put a bullet into every square yard of a football field-sized target in a three second burst. And, as long as its forty-five 200,000 candlepower flares (which would be tossed out the open cargo door) and 24,000-round basic load of ammunition held out, it could do this intermittently while loitering over a combat zone for hours. At night, the firepower that came out of that plane looked like a storm of glowing red incendiary tracers, but there were at least 5 regular rounds in between each tracer, so the rate of fire was insanely high - 6,000 rounds per gun, equals 18,000 rounds per minute. When Spooky made his appearance, the smart bad guys would break off their attack, usually trying to out-wait the gunship. If they didn't break off, and were caught in the open, they quickly joined their ancestors. One AC-47 pilot caught an entire VC battalion in the open near Nha Trang and decimated them. The morning body count was over 400.
The tracers are only one of every five bullets.
Long exposure photo - AC-47 flying low and slow.
Flares bring daylight to the target.
Long exposure photo showing the "Cone of Fire."
One of the more enjoyable missions was when Spooky was assigned to work with a C-47 psy-war aircraft - Gabby to her friends and unofficially a Bullshit Bomber. It was a standard C-47 with a large speaker mounted in the cargo door and an ARVN troop constantly rejoicing over the mike about the benefits of the South Vietnamese government. Gabby would orbit at about 3500 feet in a pylon-turn and begin talking to the "little guys on the ground" - always imploring them not to fire upon the speaker aircraft or great trouble would befall them. Unbeknownst to the black pajama crowd, Spooky was also orbiting above them, behind Gabby. Sure enough, the black pajama boys would begin firing on Gabby and the mighty wrath of Spooky would fall upon them. Whereupon Gabby would retort, "See, I told you so!"
In 1969, the AC-47 was phased out in favor of their larger, more sophisticated brothers - the AC-130 Spectre, AC-119G Shadow, and AC-119K Stinger. Eighteen AC-47s were turned over to the Vietnam Air Force. At least eleven went to the Royal Lao Air Force. And several found their way into service with both the Thai and Cambodian Air Forces. During AC-47 operations between late 1964 and early 1969, over 6000 hamlets, forts, and firebases came under the protective fire of Spooky - not one of them fell while the AC-47 was overhead. Some Spookies were lost, especially in operations against radar and anti-aircraft guns, the most formidable defenses they would ever encounter, such as missions to interdict the flow of war supplies coming down the Ho Chi Minh Trail. The greatest compliment always came from the ground troops Spooky defended. The last message on the FM net was always the same - Thanks Spooky! We wouldn't be here now without you.
In June 1967, work began on "Project Gunship II" by converting a C-130 Hercules into what was to become the best known gunship platform, the AC-130 "Spectre." We should mention that during the gunship era in Vietnam, Helicopters and other fixed-wing aircraft were used as gunships, even a rare tank, and there were a number of variations in miniguns and rotating cannons, too. In September 1967, the AC-130 prototype was deployed to Southeast Asia for combat tests, resulting in great success. Being a much larger craft, the Spectre was equipped with much more fire-power - a combination of miniguns, cannons, and even an on-board modified 105mm howitzer - much more than just an anti-personnel weapon. Like the AC-47, they carried a load of flares. These heavily armed aircraft incorporated side-firing weapons integrated with sophisticated sensor, navigation and fire control systems to provide surgical firepower or area saturation during extended periods, at night and in adverse weather. During the Vietnam War, gunships destroyed more than 10,000 trucks and were credited with many life-saving close air-support missions. The Spectre was also called Spookie or Puff. The crew, though varied, could consist of upwards to 14 personnel - five officers (pilot, co-pilot, navigator, fire control officer, electronic warfare officer); and nine enlisted (flight engineer, loadmaster, low-light TV operator, infrared detection set operator, five aerial gunners). Over the years, after several upgrades and modifications, the AC-130 still serves as the USAF's premier fixed-wing gunship.
AC-130 - Note the guns out the side.
AC-130 on a banked run.
AC-130 dropping flares, turning night into day.
This AC-130 jettisoned an angel cluster of flares.
AC-130 - minigun, cannon, and 105 Howitzer.
AC-130 - 2 miniguns up front, cannon and 105 at rear.
AC-130 - 25mm rotating cannon.
AC-130 - 40mm cannon.
AC-130 - modified 105mm Howitzer with flash shield.
Note 40mm cannon pointing down.
Return to Home Page