People operating a disconnected Buk surface-to-air missile system of the kind suspected in the downing of Malaysian Airways Flight 17 yesterday could well have had trouble distinguishing commercial flights from military aircraft, according to an article published by MIT Technology Review.
While it’s still unclear whether the plane was shot down as an act of terror or by accident, the Buk’s simple radar and isolation from air control communication systems could make such a catastrophic mistake possible, the article says, citing experts:
The Buk system was originally designed to defend advancing columns of ground troops from air attack, says Steve Zaloga, an expert on missile systems at the Teal Group, a defense-consulting firm in Virginia. Because of its purpose as a tactical weapon designed to support frontline troops, it is not connected to national air defense networks and can be operated independently, using its own radar systems, Zaloga says.
The missile operators sit inside a very cramped launch vehicle looking at a fairly basic radar screen that shows the various objects the system is tracking. But without the larger [air control communication] network, that information has very little in the way of context. That explains why its operators may not have had enough information to distinguish the civilian airliner from a military threat. “This definitely could have been an error,” Zaloga says.
A former electronic warfare officer, Michael Pietrucha, who says he trained with German forces operating a similar Russian-built system during the 1990s, said an aircraft’s transponder broadcast might not identify it as a commercial or military plane—and since the Buk is tuned out of the air control system, its operators may have been unable to make that distinction:
Military and civilian aircraft often use the same transponder modes and therefore that signal is not used as a “discriminator” for a military targeting system, Pietrucha says. The system has to be tied into the national air traffic control system to use that information effectively.