28 October 1969, the first flight of the experimental combat trainer aircraft E-155PU, which received the name MiG-25PU in serial production. The machine took to the skies test pilot Peter Ostapenko.
Flight tests of the E-155R reconnaissance aircraft and the E-155P interceptor began in March and September 1964, and in 1966 the Gorky Aviation Plant (now the Sokol Aviation Plant in Nizhny Novgorod) began building the first pre-production aircraft, which took off in 1967-1968. The military trials of the new machine and rearmament of fighter regiments started in 1970.
To train flight personnel for this aircraft, a training version of the E-155PU was created. A similar aircraft was developed for the reconnaissance aircraft. In place of the radar station installed instructor’s cabin on the model and similarity of the aircraft Tu-128U. The aircraft was equipped with a system of crew negotiations and dual control. Instead of the missing radar was put simulation equipment, and training versions of air-to-air missiles were also developed. In 1969, serial construction of twin cockpit MiG-25PU began, and until 1985, 180 such machines were produced.
In addition to its main purpose, one MiG-25PU was converted into a record-breaking E-133 aircraft in 1977. In August and October 1977, it set records for flight altitude (21209.9 metres) and speed at a distance of 500 km (2466.1 km/hour). The records were set by the future pilot-cosmonaut Svetlana Savitskaya.
Another MiG-25PU was re-equipped for optical-television observation and was used during tests on the Buran aerospace aircraft programme and in a number of other programmes. MiG-25PU-SOTN accompanied the flights of Buran analogues, performing a descent from an altitude of 18 km, conducting video recording of the test vehicle. The data were transmitted in real time to the ground control centre.
