The original developmental prototypes and concepts, to the first (pre)production aircraft. (Major variants: Ye-1, Ye-2, Ye-2A/MiG-23, Ye-4, Ye-50, Ye-50A/MiG-23U, Ye-5, MiG-21).

Ye-1 (1954)

Preliminary swept-wing design around the Mikulin AM-5A non-reheated turbojet. Instead of building it, the design was quickly reworked into the Ye-2.

Ye-2 (1954; NATO:

NATO reporting name

NATO reporting names are classified code names for military equipment of the Eastern Bloc...

"Faceplate")

Swept-wing prototype with Mikulin AM-9B reheated turbojet, armed with three NR-30 cannon, and could carry one UB-16-57 rocket pod. Fitted with RSIU-4 VHF radio, Uzel IFF interrogator, ARK-5 Amur automatic direction finder with RUP landing approach computer, MRP-48P Dyatel marker beacon receiver, SRO-2 Khrom IFF transponder, Sirena-2 RWR, SRD-1M Radal'-M radar rangefinder linked to an ASP-5N computing gunsight. Ye-2 made its maiden flight on 14 February 1955, but programme was abandoned when Mikulin RD-11 turbojet became available.

Ye-2A (1955; aka "MiG-23")

Ye-2 design modified for RD-11 turbojet. Six built. Identical to Ye-5 except for wings: Ye-2A had swept wings. Fitted with RSIU-4V radio, ARK-5 ADF with RUP module, MRP-48P marker beacon receiver, Bariy-M IFF transponder, Sirena-2 RWR, SRD-1M Radal'-M radar rangefinder with ASP-5N-V3 computing gunsight.

MiG-23 (1957; Izdeliye 63)

:Ye-2A was assigned the production designation MiG-23. It was to be much like the prototype, but with SRD-5M Baza-6 radar rangefinder and an SRO-2 Khrom IFF transponder, amongst other changes. Of twelve units planned for 1957, only five were built; these were powered by R11-300 turbojets (production version of RD-11) and had one (centreline) hardpoint to carry a 400-litre drop tank, a UB-16-57 rocket pod or a FAB-250 bomb. All work on this aircraft was ordered to be terminated in 1958, and the units built were reused for various special test programmes

Ye-4 (1955)

The first delta wing prototype of the MiG-21. Proof-of-concept testbed: used an existing production engine in a Ye-5 airframe.

Ye-50 (1956)

Swept-wing, experimental high-altitude interceptor. Ye-2 airframe modified to fit Dushkin S-155 rocket motor. Design work started in 1954, first flight in 1956. Programme terminated after crash of Ye-50/3 on 8 August 1957.

Ye-50A (1956)

Not to be confused with MiG-23 "Flogger." The Ye-50A was a refinement of the Ye-50; was to enter production and service with the designation "MiG-23U," but this didn't happen due to unavailability of the intended R11E-300 turbojet.

MiG-23U (1956; Izdeliye 64)

:U = Uskoritel ("Booster") ::This was to be production version of Ye-50A. Only one was completed due to continuing unavailability of the R11E-300 powerplant

Ye-5 (1956)

Delta wing research prototype powered by Mikulin AM-11 turbojet. Some changes besides the engine were made from the Ye-4, including addition of a second hydraulic system. The initial designation was I-500.

MiG-21 (1956; Izdeliye 65; NATO "Fishbed-A")

The first series of fighters, production version of Ye-5. Five units built at Tbilisi, but not continued due to efforts having been redirected towards the more advanced Ye-6/MiG-21F. The aircraft that were built found work as testbeds.