Ordinary Radio Waves Allegedly Can Knock Down Combat Copter

Routine radio waves can knock the Army’s most advanced battle transport helicopters out of the sky, and resulting crashes may have killed at least 22 servicemen, a published report said Sunday.

Transmissions from radio antennas, radar and microwave towers can interfere with the wiring and electrical components of the Army’s UH-60 Black Hawk helicopters and generate potentially devastating false commands, a report by Knight-Ridder Newspapers said.

Although the Army denied that electromagnetic interference (EMI) is linked to the deaths, one senior Army aviator said: “EMI is causing these aircraft to flip upside down and crash and kill everybody aboard. There is a definite problem with the Black Hawk and EMI--no question about it.”

The problem could put U.S. military forces in jeopardy during wartime because the Soviets are perfecting a radio-wave weapon to exploit the vulnerability, the report said.

Maj. Phil Soucy, a Pentagon spokesman, said Sunday the Army has conducted intensive testing into five Black Hawk crashes but has made no definitive link.

“The bottom line is that the Army has tried real hard, and it can’t link a single death or a single incident to this phenomenon of electromagnetic induction. The helicopters are susceptible (to interference) but not vulnerable,” Soucy said. “ . . . The phenomenon exists, but as we know it, it is not significant in a combat sense.”

Black Hawks are made by Sikorsky Aircraft Co., which plans to sell the Army 1,100 more helicopters by 1991 for $6 million apiece, the report said.

The Army grounded all Black Hawks last year after one crashed near a radio tower and killed three airmen, but sent them back into flight 49 days later.