IVHG-23PD / 23-01

This aircraft represented one-half of a dichotomous attack to a single objective. The specifications for the 23-01—as well as for the 23-11 or MiG-23PD (as for the MiG-21 PD, Podyomnye Dvigatyeli = lift jet), built simultaneously—called for the aircraft to be capable of speeds of Mach 2-2.3 and also offer STOL performance.

The preliminaiy designs were completed in 1964, and assembly of the prototype started in 1965. V. A. Mikoyan (son of the president of

The STOL variant with lift jets was one of the innovations explored with the 23-01.

the Supreme Soviet and nephew of A. I. Mikoyan) was commissioned to take care of both projects. For the 23-01 the design bureau chose the tailed delta configuration of the MiG-21. The midwing was an enlarged replica of that of the MiG-21. The horizontal tail surfaces were of the all-flying type (slab tailplane). Because the concept selected for this prototype was based on the employment of lift jets, the primary turbo­jet could be fed only by semicircular lateral air intakes with shock cones identical to those of the French Mirage III. Both air ducts were separated slightly from the fuselage near the air intakes to create boundary layer bleeds, and both had blow-in doors above the wing’s leading edge.

The two Kolyesov RD-36-35 lift jets rated at 2,300 daN (2,350 kg st) apiece were set in the middle of the fuselage with a slight forward incli­nation. They operated only during takeoffs and landings. For those short periods, a rearward-hinged, louvered door was opened by an actuator to supply air to the lift jets. Under the fuselage, both nozzle throats were fitted with a rotating grid that allowed the pilot to alter the direction of the thrust vector. In a way they operated as thrust reversers at landing; on the other hand, at takeoff the thrust of the lift jets was added to that of the whole power unit. The primary power plant was the R-27-300 rated at 5,095 daN (5,200 kg st) dry or 7,645 daN

Moving the air intakes to the side made room for a radar unit aboard the 23-01, here armed with R-23R and R-23T air-to-air missiles

The 23-01 on final approach, with flaps fully extended The louvered door that feeds the lift jets is open.

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The tail chute was one of several devices employed to shorten the landing roll.

(7,800 kg st) with afterburner. Like most of the MiG-21 variants the 23- 01 had the SPS system (flap blowing by air bleed downstream from the last compressor stage of the R-27-300). The canister for the cruciform tail chute was located at the base of the tail fin’s trailing edge.

Armament consisted of one twin-barrel GSh-23 under the fuselage and two air-to-air K-23 missiles under the wing (one K-23R and one K – 23T). The 23-01 was first piloted on 3 April 1967 by P. M. Ostapyenko who then took part in a series of complicated flight tests administered by V. M. Timofeyev In three months Ostapyenko acquired sufficient experience with this machine to fly it in the air display planned for 9 July 1967 at Domodyedovo to celebrate the fiftieth anniversary of the October Revolution Another ОКБ pilot, A. V. Fedotov, also flight-tested the 23-01; but this prototype had a very short life. Once the bureau’s focus shifted to the variable geometry wing, the 23-01 tests were termi­nated—immediately after Ostapyenko’s flyover at Domodyedovo— even though the aircraft’s flight envelope was left practically unex­plored with the exception of the takeoff and landing performance.

Specifications

Span, 7.72 m (25 ft 3.9 in); length (except probe), 16.8 m (55 ft 1.4 in), fuselage length (except probe), 15.995 m (52 ft 5 7 in); height, 5.15 m (16 ft 10.7 in); wheel track, 3.46 m (11 ft 4.2 in); wheel base, 6.13 m (20 ft 1.3 in); wing area, 40 m2 (430.56 sq ft); takeoff weight, 16,000 kg (35,265 lb); war load, 2,500 kg (5,510 lb); max takeoff weight, 18,500 kg (40,775 lb).

Performance

Takeoff roll with SPS and lift jets in clean configuration, 180-200 m (590-655 ft); landing roll with SPS, lift jets, and tail chute, 250 m (820 ft).