On seventies, more Turkish F-100 Supersabre and Iranian F-4 Phantom II military and other civil aircraft intruded into Soviet airspace over the Caucasus region.
Example an incident on the Iranian border occurred on 18th July 1981. An unidentified aircraft flying at about 8,000 m (26,250 ft) briefly entered Soviet airspace but then left it and the pair of 166th Guard Fighter Air Regiment PVO's Su-15 'Flagon-Ds' which had taken off to intercept it was ordered back to base.
A few hours later, however, another unidentified aircraft intruded into Soviet airspace; this time a single Su-15 'Flagon-D' of 166th Guard regiment flown by Capt. V.A. Kulyapin and armed with two R-98s scrambled to intercept it. The intruder turned out to be a Canadair CL-44 freighter leased from an Argentinean airline and flown by a Swiss crew. The fighter gave the customary ‘follow me’ signals, trying to force it down at a Soviet airfield, instead, the big turboprop started maneuvering dangerously, making sharp turns in the direction of the Su-15.
Next pictures: Soviet 166th Guard Fighter Air Regiment PVO at Marneuli, Sandar airport in 1981.