Fighter Izdeliye 95
The success of the Type 94 prompted the OKB to produce an improved frontal fighter Izdeliye 95 (MiG-21S). This was based on the 94, but with the structure once again cleared to a load factor of 8.5. h combined the F2S engine, blown Haps, new seat and canopy, large spine with two 170lit tanks, very broad fin with large cap antenna, cruciform parabrake, AOA transmitter, gun pack and five pylons, with an upgraded radar, the RP-22 Sapfir.
The offset air-data boom was of the new PVD-7 type, with a ram inlet, three rows of static apertures and weathercock vanes for AOA and sideslip/yaw. This was connected via the Pion-N (peony) feeder coupler to the optical sight and various subsystems, but the cockpit instruments were served mainly by the small auxiliary pilot near the windscreen and the AOA sensor on the left of the nose.
Developed by the Volkov KB, the new radar fitted into the existing compartments and nosecone but had greater emitter power, increasing range against the standard 16sq m (172sq ft) target to 30km (18.6 miles), with a tail-on pursuit range of 15km (9.3 miles). This radar was fitted in 1964 to prototypes designated Ye-7S (from Sapfir). A large order for Frontal Aviation was placed in the same year, and the production aircraft, designated MiG-21S, was produced at Gorkiy in 1965-68. In the course of production the TS-27AMSh rear-view periscope was added.
The better radar and extra pair of pylons greatly increased capability, but at the expense of continued degradation in MiG-21S performance. Compared with the initial production MiG-21F, normal loaded weight had increased by some 1.5 tons, with little change in engine power. Despite the substantial increase in internal fuel, rearward shift in the centre of gravity made it impossible to use all of this fuel safely, with the result that the range without drop tanks had actually decreased. The ASCC name for MiG-21S remained “Fishbed-H”