The U.S. Army Designed One of the First Helicopter Gunships On a Napkin

WIB history September 13, 2016 0

General Electric’s weapons pod didn’t work out by JOSEPH TREVITHICK In the summer of 1956, U.S. Army colonel Jay Vanderpool found himself in Burlington, Vermont...

General Electric’s weapons pod didn’t work out

by JOSEPH TREVITHICK

In the summer of 1956, U.S. Army colonel Jay Vanderpool found himself in Burlington, Vermont for a secretive meeting with engineers at General Electric. The officer wanted to find out if the manufacturing giant could build weapons for a new type of military vehicle — a helicopter gunship.

That June, the commandant of the U.S. Army Aviation School Gen. Carl Hutton had brought Vanderpool out of retirement to develop and experiment with armed copters. Fearing the ground combat branch’s top leaders would scrap his pet project, the general initially ordered the work be done with no official orders and no budget.

“Armed with only a drawing on a paper napkin and no money, the colonel asked G.E. to build a rocket kit for a helicopter,” Army major Charles Griminger and Dr. Aaron Rose wrote in a historical study of gunships for the Aviation School in 1968. The company’s representatives “agreed to build the kit and promised it in three months.”

The firm ultimately built a pod with eight 89-millimeter rockets and two 7.62-millimeter machine guns.

When Vanderpool first got down to business at the Aviation School at Fort Rucker, Alabama, one of the biggest hurdles was that no one knew what a gunship was supposed to look like. During the Korean War, troops had tried firing a bazooka from a small Bell H-13 scout helicopter.

In 1953, soldiers in Japan built a home-brew grenade-dispenser for their own copters. The Marines had tried launching rockets from a larger Sikorsky H-19 transport.

Above, at top and below — G.E. Ground Fire Suppression Kit during Army tests. U.S. Army photos via Ray Wilhite

Across the Pentagon, the consensus was that existing helicopters were simply not powerful enough to withstand the shock of firing heavy machine guns, automatic cannon or rockets. But Hutton and Vanderpool were undeterred.

French forces appeared to be having some success with weapon-carrying copters as they battled insurgents in Algeria. Many of France’s gunships were based on American helicopter types.

In July 1956, Vanderpool’s unit at the Aviation School — quickly nicknamed Vanderpool’s Fools after his odd collection of spare copters and prototype weapons-packs — rigged up its first actual live-fire test. Worried about safety, the troops put an H-13 on an elevated platform and fired machine guns and rockets from a safe distance.

Everything went fine and the helicopter and the platform remained intact. With this successful proof-of-concept in hand, the group quickly expanded its arsenal.

Enter G.E.’s “Ground Fire Suppression Kit.”

Back in Burlington, engineers Thurlow Mayhood and Jack Harding were busy turning the napkin art into a real weapon. We don’t know what Vanderpool described in his original drawing, but the two designers built a pod around some of the newest weapons available at the time.

At the center of the sheet metal case were eight rocket tubes. Each held a single experimental 89-millimeter T-290 rocket.

Huey Cobra Gunships (New Vanguard)

Two T-161 machine guns — prototypes of the gun that eventually became the Army’s iconic M-60 — sat on either side of the launchers. Magazine for each weapon held 300 rounds of ammunition.

Without the the rockets or the guns, the pod itself only weighed approximately 50 pounds. Troop could quickly attach the whole setup to an H-13 helicopter’s skids using four small brackets.

“The Ground Fire Suppression Kit can be installed on or removed from the helicopter, without the use of special tools, in a matter of minutes by two men,” a contemporary sales pamphlet declared. “A defective pod can be quickly replaced with a spare unit, and routine maintenance can be performed without the use of special tools or equipment.”

The packet includes illustrations showing the weapons on Hiller UH-12 and Kaman K-600 copters in addition to the Army’s H-13. I found a copy of this document in the National Air and Space Museum archives.

As Mayhood and Harding’s design was one of the first such weapons, there were few other examples to serve as reference points. The designers were winging it. And, as a result, the kit suffered significant problems.

Some of these were not necessarily a product of the pod itself. Although G.E. had intended for two pods to be mounted on a helicopter at once, the company only managed to delivered one.

With all the weight on one side, troops found the copter hard to control. Putting ballast on the other side to even things out only helped so much.

On top of that, by the time the first package arrived at Fort Rucker, the Army had shot off the entire supply of T-290 rockets and wasn’t planning on buying any more. Engineers had to modify the kit to use 2.75-inch folding-fin aerial rockets.

These projectiles were significantly longer and more powerful. In the end, only four of the eight tubes could safely fire the new rockets.

Still, some of the issues were the fault of the pod itself. Since the machine guns could only accept belts of ammunition from one direction, the left weapon was awkwardly installed upside down so the belted rounds could feed straight and avoid jamming.

Troops complained that the gun was hard to reload on the ground, according to Griminger and Rose. Soldiers would have had to remove this gun from the kit to feed in new ammunition.

Since the pod was slung under the landing skids, there was an inherent danger of scraping the ground on uneven terrain. Fliers bent or broke the newly modified extra-long rocket rubes sticking out the back.

Perhaps most damning was the simple fact that Vanderpool’s Fools eventually ended up with 20 other armament packages for four different helicopters. The unit had other, simpler options readily available.

For scout helicopters such as the H-13, the Army eventually settled on a pair of machine guns rigged on top of the skids. The ground combat branch’s own Springfield Armory was responsible for the final design.

G.E. never found a buyer for its pod, but the company continued to build Gatling guns and other weapons for gunships into the 1980s.