8TP/8TK IRST
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Developed by a team lead by D M Khorol at Geofizika, starting in 1970.
The 8TP is installed in a retractable cylindrical housing, and uses liquid nitrogen cooling. Testing started in 1977, and was declared operational with the MiG-31 in 1981.
Scan angles of the 8TP are +-60 degrees in azimuth, +6/-13 degrees in elevation. Angular resolution is 15 minutes. Power consumption of the unit is 1.3kW, MTBF 350h, weight 124kg.
Range is about 40km against a rear aspect fighter target in military power, 100-120km against an SR-71 in full afterburner.