Shoot ‘Em Up

Sometimes you have to destroy the aircraft in order to save it.

A live-fire test on a North American F-86. During the Vietnam War, engineers looked for ways to toughen aircraft against ground fire and surface-to-air missiles. (U.S. Navy)
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Someday, on a mission to extract a special operations team, a pilot will fly into enemy territory in an MH-60S, a forthcoming U.S. Navy version of the Sikorsky Black Hawk helicopter, and an anti-aircraft round will drill into the MH-60’s rotor drive system. For the shooter on the ground, hitting the helicopter won’t be easy—it will be moving fast, the rotors and shaft spinning faster—but there are always lucky shots. The pilot will feel a jolt and wonder if his aircraft can survive the strike.

Joe Manchor is about to find out, long before the pilot has to. Dressed in sneakers and blue jeans, the lead engineer on the live-fire test and evaluation of the MH-60S has a prototype of the helicopter locked onto a steel platform, dead in the sight of a nasty-looking gun. We’re at the Naval Air Warfare Center’s Weapons Survivability Laboratory at China Lake, California. The rig is 10 miles into China Lake’s hidden city, 3,800 square miles—an area the size of Delaware—of high Mojave scrub and mountains. Outside the sky is deep blue, the winter sun glaring, but we’re hunkering in a windowless control room protected by a 20-foot-tall wall of steel plate. Two hundred yards away on a test pad stands the helicopter, prepped for its final judgment. Though it was built with care and is worth over $10 million (and no doubt coveted by dozens of aviation museum curators), it is being sacrificed for the future glory of the MH-60s that will go to war.

The helicopter is bolted to a system of steel beams and remotely controlled airbags and actuators that took eight months to design and build. Mounted on another steel frame 30 feet from the MH-60 and level with its rotor mast stands the remotely operated, electronically fired gun. Exactly what bullet it’s about to shoot is classified, but the gun is capable of firing a 7.62-, 12.7-, 14.5-, 23-, or 30-mm anti-aircraft round. If the test works as planned, the gun will fire 0.0012 second before the helicopter’s pitch control link spins into its sights, enabling the projectile, traveling at 2,510 feet per second, to smash into its laser-painted bull’s-eye. High-speed video cameras will record the shot, allowing Manchor and his team to analyze what happens as the bullet finds its mark.

Such sacrifices are routine at China Lake, where combat aircraft both old and new are methodically destroyed by guys like Manchor. The tests have changed the way airplanes and helicopters are designed and have enabled pilots to get safely home in aircraft riddled with holes. “We lost 5,500 helicopters and airplanes in Vietnam,” says Robert E. Ball, Distinguished Professor, Emeritus, at the Naval Postgraduate School in Monterey, California, “and in Desert Storm, four [F/A-18] Hornets got hit by infrared [-guided] surface-to-air missiles and all came back.” Ball’s textbook on aircraft survivability is the discipline’s bible.

As effective as live-fire survivability testing seems, however, it is controversial. Contractors and program managers chafe over the time-consuming and destructive testing, which will reveal flaws in expensive hardware only after its development is well under way—sometimes at the stage of full-scale production. Today’s single shot at the MH-60’s pitch control link—a slender rod that adjusts the pitch of the rotor blades—has taken several days to set up. The complete MH-60 live-fire test sequence will take three years. Should serious vulnerabilities be uncovered, key components will have to be redesigned.

Survivability, according to WSL director Jay Kovar, is determined by the answers to a series of three questions: “Can he see me? If he can see me, can he hit me? If he can hit me, can he kill me?” The operation run by Kovar, a strapping former nationally ranked discus thrower, focuses on the last question in the series.

In the opening days of World War II, airplanes were easy to see, hit, and kill. On May 14, 1940, the British lost 23 of 64 Blenhiem and Fairey Battle bombers. And when Germans invaded the Soviet Union a year later, more than 1,400 Soviet airplanes were lost in a single day. As the war ground on, air forces tried to decrease the visibility of aircraft or increase their defenses. “Think about it,” says Robert Ball. “Eight of the 10 men in a B-17 were manning machine guns, and the weight of the guns and ammunition was about twice the weight of the bombs carried.”

By the time of the Vietnam War 20 years later, little had changed. “There was very little attention paid during the design of any aircraft of that era to the damage that enemy guns or guided missiles might do,” says Ball. Increasingly sophisticated high-altitude surface-to-air missiles forced pilots to fly low, which made them vulnerable to small arms fire.

“All of the planes flying in Vietnam were designed for a completely different environment,” says Chuck Myers, the former director of air warfare in the Office of the Secretary of Defense. “The F-4’s mission was to intercept incoming bombers and hit them with Sparrow missiles. The F-105 was designed as a low-altitude nuclear-strike airplane to drop bombs and leave. You didn’t worry about bullets. But those planes were terribly vulnerable. We sent them into the conventional [warfare] morass of Vietnam, and when those SOBs got hit with bullets they came apart.” Ditto with helicopters, which were used in combat in large numbers for the first time in Vietnam. By 1970 some 1,500 had been shot down; their fast-spinning turboshaft engines and light materials proved highly vulnerable to 23-mm anti-aircraft fire.

With losses so high, the Air Force Systems Command dispatched a fact-finding team to Vietnam in 1966 to determine the cause. The directive setting up the mission included the conjecture that aircraft were crashing from catastrophic structural damage. But Dale Atkinson, then an aerospace engineer at the Air Force’s flight dynamics laboratory, thought otherwise. After examining damaged aircraft and talking to surviving crew members and wingmen, Atkinson concluded that airplanes were taking hits and still flying, only to crash because of the fuel system fires and explosions ignited by incendiary ammunition and because of flight control damage.

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