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The A-37 Dragonfly in Vietnam

When light attack was the real thing

A small cadre of mid-grade Pentagon officers — the “renegades,” some call them — are arguing for a light attack capability for the U.S. Air Force.

 “We had more time on station than the big fighters and unlike them we could operate under cloud cover and in tough terrain that might have deterred a larger jet.”

Believing the United States will find itself fighting in Third World trouble spots for years to come, they want the Air Force to have its own squadrons of a warplane in the category of today’s Sierra Nevada Corp./Embraer A-29B Super Tucano or Beechcraft AT-6 Texan II.

A-37B Dragonfly

A formation of Cessna A-37Bs of the 757th Special Operations Group, Air Force Reserve. The A-37B Dragonfly was an example of the U.S. Air Force getting the light attack concept right. U.S. Air Force photo

The light attack concept has been under study since the 1950s, but in the opinion of many the Air Force only got it right once – during the Vietnam War with the Cessna A-37B Dragonfly.

“Our troops on the ground were glad when the aircraft coming to help them was an A-37,” said retired Lt. Col. Dennis Selvig, who piloted A-37Bs with the 604th Special Operations Squadron (SOS) at Bien Hoa from March 1970 to March 1971. “The bigger fighters were less able to help them out of a tight spot. We had more time on station than the big fighters and unlike them we could operate under cloud cover and in tough terrain that might have deterred a larger jet.”

“It was bulkier,” says retired Lt. Col. Cort Durocher, who also piloted the A-37B with the 604th squadron. “It was on steroids. It had a bigger engine. This was a sturdy combat aircraft, not a flimsy trainer.”

The straight-wing, two-seat A-37B (its second seat unused most of the time) was a true light attack aircraft of the kind the Pentagon upstarts want today. Still, when considering the A-37B it’s important to distinguish between little and little. Contrary to appearances, the A-37B was bigger in every way than the T-37 “Tweet” jet trainer from which it was derived.

“It was bulkier,” says retired Lt. Col. Cort Durocher, who also piloted the A-37B with the 604th squadron. “It was on steroids. It had a bigger engine. This was a sturdy combat aircraft, not a flimsy trainer.”

A-37B Dragonfly

Then-1st Lt. Cort Durocher poses with an A-37B Dragonfly of the 604th Special Operations Squadron at Bien Hoa, South Vietnam. Photo courtesy of Cort Durocher

The light attack concept that yielded the Dragonfly predates the Vietnam War. The U.S. Army evaluated the T-37 trainer for a combat role from 1956 to 1958, during Project Long Arm, when three T-37s in Army markings operated from Salinas, Calif., and flew simulated close air support strikes at nearby Fort Ord. Half a decade later, the Air Force invested in two armed AT-37D demonstrators, which acquitted themselves well in an evaluation. By the time the AT-37D made its formal first flight on October 22, 1963 – with a J85 engine replacing the J69 used on the trainer – the United States was becoming deeply embroiled in Vietnam, and a combat aircraft based on the “Tweet” was an idea that was belatedly revived.

 

Dragonfly Orgins

The Air Force evaluated the AT-37Ds between 1964 and 1966. At one point, after it was thought tests were completed, one of them had to be hauled out of the Air Force Museum to resume further evaluation. In 1967, the Pentagon hired Cessna to modify 39 T-37 trainers into A-37As. Later that year, the Air Force sent 25 A-37As to Southeast Asia for combat evaluation under the name Combat Dragon. These aircraft flew close air support, night interdiction, and forward air control missions in South Vietnam and southern Laos.

“Delivering ordnance in an A-37B was a little like throwing a rock at a fence post, and you didn’t really need a sight.”

Based on the successful results of Combat Dragon – the name has been reprised for the today’s ongoing light attack demonstration, Combat Dragon II – the Air Force ordered newly-built A-37Bs, which introduced cockpit armor, more powerful engines (J85s), redundant flight controls, provision to receive aerial refueling, and a strengthened airframe.

The A-37B had four under-wing hardpoints and pylons on each wing, with provision for a variety of weapons (often 500-pound Mark 82 bombs), self-sealing fuel tanks, and a General Electric GAU-2B/A 7.62mm minigun mounted in the nose compartment with 1,200 rounds of ammunition.

A-37B Dragonfly

The Cessna A-37B’s GAU-2B/A 7.62mm minigun was mounted in a nose compartment along with 1,200 rounds of ammunition. U.S. Air Force photo

Former Staff Sgt. Fredric Neumann, a maintainer who served with the 604th squadron, said, “The A-37 followed the KISS principle (‘keep it simple, stupid’). It was well equipped for operations from primitive airfields and required little of the fancy, high-tech maintenance needed by more sophisticated warplanes like the F-4 Phantom II.”

Of 577 A-37Bs built, the Air Force eventually turned 254 over to the South Vietnamese Air Force to replace its aging A-1 Skyraiders. Most pilots, including Vietnamese pilots, were trained in the A-37 at England Air Force Base near Alexandria, La.

Retired Col. Hank Hoffman, a pilot in the 604th SOS remembered how a typical mission began: “The A-37B looks tiny in its concrete nest designed for a bigger fighter. I take one step over the side of my bird onto the survival cushion that we sit on, and plop my ass down on it while turning on the battery switch. The crew chief is holding the shoulder straps of the parachute and seat harness over my shoulders and I slip into them. Just two buckles secure me, those for the parachute, and survival kit. I push one button to start number one engine even before the chief is gone from in front of it. At 15 percent power, it gets gas from the throttle. At 45 percent power, I start the other engine. As number two comes up to idle I pull forward outside the revetment and look for the Plumber” – wingman 2nd Lt. Chuck “Plumber” Purcell – “who is right behind me.

“I speak rapidly on the radio: ‘Bien Hoa ground, HAWK One scramble two!’

A-37B Dragonfly

Then-Capt. Hank Hoffman climbs into an A-37B Dragonfly at Bien Hoa, South Vietnam. Hoffman piloted A-37Bs for the 604th SOS during the Vietnam War. Robert F. Dorr Collection

“Bien Hoa says, ‘HAWK One clear to taxi.’ Plumber says, ‘Two!’ and we’re on our way, not forgetting to salute the crew chief. He will worry about us while we’re gone.”

 

Into the Cauldron

Working with a forward air controller, or FAC, in an O-1 Bird Dog, Hoffman flew his A-37B into the fight. He carried a typical warload known as “shake and bake” – two Mark 82s and two 500-pound cans of napalm. He was ready, also, to use the 7.62mm gun possibly with, or possibly without, his crude gunsight. “The sight gave you a reticle where you could put in a mil setting for the type of ordnance you were carrying,” Hoffman said. “On some missions, I never turned it on. Delivering ordnance in an A-37B was a little like throwing a rock at a fence post, and you didn’t really need a sight.”

It was like using a hose. You could walk your rounds where you wanted them to go but it wasn’t easy.”

“We would have preferred a .50-caliber gun,” Hoffman said. “Our 7.62-mm wasn’t really effective. It was like using a hose. You could walk your rounds where you wanted them to go but it wasn’t easy.”

Guided by a FAC, able to operate beneath cloud cover where an F-4 Phantom II or F-100 Super Sabre couldn’t, Hoffman and his A-37B found Viet Cong troops approaching the friendlies. Hoffman followed the usual tactic of dropping his explosive bombs first, and then came around and released the napalm. “The easiest mistake to make in bombing is the ‘long-short error.’ You never attack by flying over the friendlies. You fly parallel to the battle line on the enemy’s side.” Hoffman said he rarely used the gun but other A-37 pilots used it frequently.

A-37B Dragonfly

An A-37B of the Vietnam Air Force (VNAF) flying out of Da Nang Air Base, South Vietnam. Simple to maintain and effective, it was ideal for the VNAF. U.S. Air Force photo

Veterans of A-37 duty say they never killed or wounded a friendly by mistake.

Hoffman and other pilots coaxed extra endurance out of the A-37B by routinely flying on one engine and leaving the other shut down. The A-37B had more than enough power and this simple step enhanced endurance and flexibility.

Surviving examples were retained in service and took on FAC duty, becoming OA-37Bs, with two Air National Guard squadrons and an Air Force composite wing at Howard Air Force Base, Panama as late as the late 1980s.

Two 2,850-lb thrust General Electric J85-GE-17A turbojet engines powered the A-37B. These provided about 30 percent more power and about 20 percent higher speed than the trainer version. Yet the A-37 was well equipped for operations from primitive airfields and required little of the fancy, high-tech maintenance needed by more sophisticated warplanes. It was ideal for use by Vietnamese forces, which had some excellent pilots but overall lacked the standard of training and expertise found in the U.S. Air Force.

Surviving examples were retained in service and took on FAC duty, becoming OA-37Bs, with two Air National Guard squadrons and an Air Force composite wing at Howard Air Force Base, Panama as late as the late 1980s. Fully 169 A-37Bs were delivered to Chile (34); Colombia (26); Ecuador (12); El Salvador (21); Guatemala (13); Honduras (15); Peru (36) and Uruguay (12), with other nations such as the Dominican Republic later acquiring them secondhand. A-37Bs have seen combat bombing rebels in Nicaragua (by Honduran aircraft); Guatemala, and Colombia.

A-37B Dragonfly

The A-37B Dragonfly was widely exported to nations in Latin America. This example was on duty in the Dominican Republic in March 1996. The Dominican Republic received their A-37Bs secondhand. Robert F. Dorr Collection

Col. Michael Pietrucha, one of today’s “renegades” advocating for a new light attack fleet — though he doesn’t use the term — told Defense Media Network he is “platform agnostic” but was influenced by the fact that the A-37 underwent a combat evaluation “in country, under real-world conditions.” Pietrucha is the officer responsible for resurrecting the Combat Dragon program name. “I intended that a handful of guys would take a few light attack aircraft into the combat zone and demonstrate its capabilities. The A-37 experience was a strong influence.” As it turned out, Combat Dragon II took place in the United States rather than, as hoped, in Afghanistan.

 

Cessna A-37B Dragonfly

Type: Two-seat fighter and attack aircraft

Powerplant: Two 2,850-lb (1293-kg) thrust General Electric J85-GE-17A turbojet engines

Performance: Maximum speed at 16,000 ft (4875 m) 524 mph (834 km/h); maximum cruising speed at 25,000 ft (7620 m) 489 mph; range with maximum payload, including 4,100 lb (1860 kg) of external weapons, 460 miles (740 km)

Weights: Empty equipped 6,211 lb (2817 kg); maximum takeoff 14,000 lb (6350 kg)

Dimensions: Span 35 ft 10-1/2 in (10.93 m); length 28 ft 3-1/2 in (8.62 m) without refueling probe; height 8 ft 10-1/2 in (2.71 m); wing area 183 sq ft (17.98 sq m)

Armament: One .30 cal. (7.62mm) GAU-2B/A Mini-gun; typically up to 5,000 lb (12268 kg) of Mark 82 500-lb (227-kg) or heavier bombs, napalm, or air-to-ground rocket projectile

First flight: Oct. 22, 1963 (YAT-37D); May 2, 1967 (A-37A); circa May 1, 1968 (A-37B)

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Robert F. Dorr is an author, U.S. Air Force veteran, and retired American diplomat who...