Ye l/Kh-1 / Ye-2/Kh 2

In the first half of the 1950s the military called for the development of a lightweight frontline fighter capable of speeds of Mach 2 and a ser­vice ceiling of 20,000 m (65,600 feet). Initial work was concerned with the test and aerodynamic refinement of a set of thin-airfoil wings char­acterized by a 55- to 57-degree sweepback at the leading edge, with the

design of reliable flying controls for transonic speeds and Mach num­bers between 1.5 and 1.7, and with the selective examination of all pos­sible power plants—including several types of turbojets associated with supersonic air intakes.

Such were the basic considerations that led in 1954 to a prelimi­nary design named Ye-1 or Kh-1 and powered by the AM-5A turbojet. This first draft was quickly modified during that same year and became the Ye-2 powered by the AM-9B turbojet with afterburner, a Mikulin engine that had been retained to power the mass-produced MiG-19. (The AM-11 was the engineers’ first choice, but it was not yet avail­able.) The Ye-2 was planned as a single-engine fighter and thus had 2,550 daN (2,600 kg st) of thrust available, or 3,185 daN (3,250 kg st) with afterburner.

It was decided to keep the aircraft’s master cross-section as little as possible because it was proportioned by the small volume of the cock­pit (1 m3 [35.3 cubic feet]) and the dimensions of the engine. The two – spar stressed-skin wing had a sweepback of 55 degrees at the leading edge and a thickness ratio of 6 percent. The Fowler flaps were hydraulically controlled. The two-segment ailerons were mechanically linked to the spoilers. The outer halves of the leading edge were fitted with two-segment slats. The cockpit canopy structure and the ejection seat were identical to those aboard the 1-3, and the canopy protected the pilot in case of ejection.

The windshield was heated by electrical wires set into the triplex glass interlayer. Flying controls were of the rigid type, the rudder being controlled by actuating rods that extended through the dorsal spine of the fuselage behind the cockpit. The slab tailplane was controlled by a servo-control unit located in the fin root. Each of the four fuselage tanks was cut off from the others by special nonreturn valves in order to improve the fuel system’s fatigue resistance. The turbojet plus after­burner bay was cooled by ventilation between the combustion cham­ber shroud and the fuselage skin. As the aircraft accelerated, ventila­tion was relative to ram air pressure; at zero airspeed, the engine bay was cooled by the discharge of sucked-in air.

The landing gear took up much less space. The main gear wheels retracted into the fuselage, while their legs folded into the wing between the fuel tank/wing box and the rear spar on which the flaps were hinged. This mechanism was later used on several types of MiG fighters because it cut the structure’s weight significantly. Armament consisted of two NR-30 cannons located in the lower part of the nose. The ammunition belts were housed in circular sleeves placed between fuselage bulkheads. Main equipment and accessories included the RSIU-4 VHF, the Uzel system’s homing receiver, the ARK-5 automatic direction finder, the MRP-48 ILS, the Radal-M ranging radar linked to the ASP-5N gunsight, and a radar warning receiver.

The Ye-2 was first piloted by G. K. Mosolov on 14 February 1955 but finished only a part of its test schedule, which was completed by the reengined Ye-2A.

Specifications

Span, 8 109 m (26 ft 7 2 In); length (except probe), 13.23 m (43 ft 4 9 in); fuselage length (except cone), 11 737 m (38 ft 6 1 in); wheel track, 2.679 m (8 ft 9 5 in); wheel base 4.41 m (14 ft 5.6 in); wing area, 21 m2 (226 sq ft), empty weight, 3,687 kg (8,125 lb), takeoff weight, 5,334 kg (11,755 lb) fuel, 1,360 kg (3,000 lb), wing loading, 254 kg/m2 (52 lb/sq ft)

Performance

Design max speed, 1 920 km/h (1,037 kt); landing speed, 250 km/h (135 kt), design service ceiling, 19,000 m (62 300 ft), takeoff roll, 700 m (2,295 ft), landing roll, 800 m (2 625 ft)