MiG-21 / Yg-E/1 / Ye-E/2 / Ye-E/3 |Ye-BB|

The first three MiG-21 prototypes, Ye-6/1, Ye-6/2, and Ye-6/3, were built and flight-tested in 1957 and 1958. They were powered by a new version of the AM-11 turbojet, the R-11F-300 (developed from the experimental R-37F) rated at 3,800 daN (3,880 kg st) dry or 5,625 daN (5,740 kg st) with afterburner. Their stabilators were lower than that of the Ye-5, forcing designers to rearrange the airbrakes in these units; the two canted ventral fins on the fuselage under the tail were replaced by a single unit; the nozzle throat was lengthened; and the rear part of the cockpit hood was redesigned. Only the Ye-6/1 retained the six wing fences first seen on the Ye-5.

The MiG-21’s airbrakes closely followed the shape of the NR-30 gun fairings.

In no time the Ye-6/1 reached Mach 2.05 at 12,050 m (39,520 feet). But the seventh flight, on 28 May 1958, ended in tragedy after the engine failed at about 18,000 m (59,040 feet). The test pilot, V. A. Nefyedov, struggled desperately to return to the airfield in order to save the aircraft and the recording of all its flight data. He made it to the runway, but as the plane touched down it overturned and caught fire Severely burned, Nefyedov died in a hospital a few hours later. The official inquiry established that the pilot was betrayed by the pres­sure drop in the hydraulic system due to engine failure. Because the stabilator was hydraulically controlled the standby electrical control was automatically activated, but it took the backup unit far too long to set the stabilator at the proper angle. As a consequence the hydraulic system on the Ye-6/2 was duplicated and backed up by an emergency pump, and the electrical control unit was removed. К. K. Kokkinaki was given responsibility for the Ye-6/2 test program. This second pro­totype, numbered 22, was equipped experimentally with missile launching rails at the wing tips.

The Ye-6/3 made its first flight in December 1958 and became world-famous a few months later under the fanciful designation Ye-66 while beating two world records:

1. 31 October 1959. Speed over a 15- to 25-km (9- to 16-mile) course at unrestricted altitude, 2,388 km/h (1,289.52 kt). Pilot, G. K.

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MiG-21F (MiG OKB three-view drawing)

3740

A MiG-21F equipped experimentally with K-13 air-to-air missiles under wing pylons. The cannons were removed.

Mosolov. Highest speed attained during this flight, 2,504 km/h (1,352.16 kt)

2. 16 September 1960. Speed over a closed circuit of 100 km (62 miles), 2,148.66 km/h (1,160.28 kt). Pilot, К. K. Kokkinaki. High­est speed attained during this flight, 2,499 km/h (1,349.46 kt) or Mach 2.35

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