The Soviet air defense command in the Kamchatka Peninsula region has standing orders to force down any unauthorized aircraft that penetrates Soviet airspace, according to Soviet specialist Dimitri K. Simes.

"I was at Kamchatka in 1969 and lectured to pilots there, and they told me how they operate," said Simes, a Soviet emigre and a senior fellow at the Carnegie Endowment for International Peace.

Simes said any intruding aircraft sets in motion a standard procedure. Fighter planes are launched, and military district headquarters is contacted. "No special order is needed, or expected, to force the plane to land. The assumption is that the plane . . . must be forced to land," he said.

Interceptors have instructions to identify themselves and make visual contact, he said. If the intruder "refuses to cooperate," he said, pilots "fly in front of it to be absolutely certain the pilot is aware of what is going on."

Next come "warning shots" that, if unheeded, are followed by "wavering fire . . . to put the onus of decision on the intruder's crew," he said.

"The assumption is that if the pilot has nothing to hide, he will land" or be shot down, Simes said.

A jumbo jet operating in the area for a considerable time would require communication with air defense headquarters in Moscow, and "a new decision" there would be required to overturn standard operating procedure, he said.

"In other words, it would require a decision to let this plane pass," he said.