Unconventional Weapon

What we learned about stealth technology from the combat career of the F-117

Staff Sergeant Robin Walker (left) reports no foreign objects in the inlets to Staff Sergeant Greg Slavik piror to takeoff from Nellis Air Force Base in Nevada. (Tech. Sgt. Kevin J. Gruenwald/USAF)
Air & Space Magazine

(Continued from page 4)

Nadir Over Serbia

On March 27, 1999, an F-117A that had just bombed a target in Serbia was shot down 28 miles northwest of Belgrade. The weapon that shot it down was a veteran S-125 Neva-M missile system.

The other side of the story emerged in late 2005, when the Serb commander whose battery had planned the attack discussed it in detail for the first time. Colonel Dani Zoltan—whose traditional Hungarian name had not been released because it wasn’t Serbian, a testament to the bad blood between the two nations originating in Hungary’s World War II invasion of Yugoslavia—emerged as an energetic and original leader who used good tactical sense and modified equipment to down the world’s most sophisticated stealth aircraft.

To keep his radars and operators from being attacked, Zoltan kept them on the move. He led the Third Battery of the 250th Missile Brigade on more than 50,000 miles of blacked-out travel in the 78 days of the war. He also made unspecified modifications to the P-18 radar.

Resembling a Rube Goldberg assembly of housetop TV antennas, the P-18 differed from most radar because it operated in the VHF waveband, transmitting at a much lower frequency than most other radars. The radar-absorbent material covering the F-117 is less effective against VHF radars.

The jet’s primary defense against VHF resides in the wing edges, which take the form of deep and effective absorbers, called an “electromagnetic shock absorber” by chief engineer Alan Brown in a 1992 lecture.

Avoiding detection by systems like the P-18 required a combination of careful planning, operational security, and tactics. But Zoltan’s hyperactive battery couldn’t be pinned down. Serb agents were tracking takeoffs from the F-117s’ base in Aviano, Italy, and airspace restrictions indicated that the fighters were following very similar routes, night after night.

According to Dani, when the F-117A was head-on at 26,000 feet and eight miles out, the battery fired two missiles. Each would have closed the distance in seconds. The pilot, Air Force Lieutenant Colonel Darrell Zelko, has never specified how much warning he had of the attack. One still-classified aspect of the F-117 is whether it carries any kind of radar warning receiver. If it does, even the most comprehensive studies of the aircraft have not mentioned it, nor has it been mentioned as part of any upgrade.

A December 2006 account of the shootdown in Air Force magazine says only that Zelko’s “routine suddenly was shattered by indications that Serbian air defense systems had targeted his aircraft.” (Zelko ejected and was rescued by an MH-60 Pave Hawk helicopter six hours later.)

The shootdown led to such changes as the formation of an F-117 weapons school to develop, formalize, and train in tactics, and an increased emphasis on training with other forces, including the jet’s first participation in Red Flag war games. “Stealth is not perfect, and we still count on other assets to improve our capability,” Shoaf told the London conference.


Comment on this Story

comments powered by Disqus