Version number 2: loss of consciousness by Seregin
During the flight, Seregin could have a heart attack - he piled on the control panel and blocked it. Gagarin was unable to eject due to the special system of the aircraft. The ejection seats in the training MiG-15 are triggered in turn: first, the instructor sitting in the back leaves the cockpit, and only then the student. True, in this case it remains unclear why Gagarin did not report the situation to the ground.
Version # 3: loss of consciousness by both crew members
The aircraft was at an altitude of 4000 m. During the flight, the cockpit could be depressurized. Feeling the lack of oxygen, the pilots attempted a sharp decline. There was a pressure surge, resulting in a loss of consciousness.
However, this version has its own Achilles heel: both pilots were trained people. An altitude of 4000 m from the point of view of oxygen deficiency should not have become critical for them. In addition, Gagarin and Seregin had a solid age difference (the first turned 34 at the time of his death, the second 45). According to doctors, hypoxia could not affect them in the same way. If the pilots lost consciousness, it would not be at the same time.
Version No. 4: hooliganism in the air
In the 50-60s. aerial hooliganism among Soviet pilots was widespread. Gagarin and Seregin, contrary to the order, could not set the course for a return, but engage in complex aerobatics at low altitude. Performing risky maneuvers led to disaster.
Version No. 5: negligence of the flight director
It is known that the flight director provided Gagarin and Seregin with outdated data on weather conditions. The pilots should have received a fresh forecast already at altitude, but for some reason the information was never transmitted.
On March 27, 1968, the cloud base in the northeast of the Moscow region was at a level of 400 m from the ground - such conditions were not suitable for difficult maneuvers. Performing a descent from the aerobatic zone, the pilots made a coup with a dive exit and got into a zone of increased cloudiness. At the same time, they did not worry, since their data on the cloud boundary were incorrect (according to the head's information, the lower edge was at an altitude of 900 m). As a result, when the pilots saw the ground, the altitude for level flight was simply not enough.
In what year Gagarin died, today every schoolboy knows. But the reasons for the death of the astronaut can only be guessed at. Each of the voiced versions has the right to exist, and each may turn out to be the only true one. However, most experts are inclined to believe that the leaders of the Center should be considered the culprits of the tragedy: too many disciplinary violations were revealed during the investigation. This version explains well why the "Gagarin case" was quickly put on the shelf. Indeed, otherwise, many high-ranking officials would have to bring charges - including the Air Force High Command, which is responsible for order in the units entrusted to them..