In 1968, Kuznetsov and others were investigating the causes of the Mig-15 disaster that killed the two men.
During the past 37 years, many versions of the accident have circulated, but the main question - what happened to the plane and its crew during the last 68 seconds of flight - remains unanswered.
Kuznetsov's conclusions are sensational. He claims Gagarin and Seryogin were unconscious during the fall and could not pull out of the steep descent. He says the cause was a vent cock somebody left open in Gagarin's cabin, leaving the cabin unpressurized from the flight's start. The pilots could not have known this until they reached an altitude of more than two thousand meters. In the emergency, they acted according to instructions -aborting the mission and promptly descending to a lower level. Seryogin made the "dive", Kuznetsov says. But the plane never pulled out of its descent.
According to Kuznetsov, the pilots were at an altitude of 4,200 meters in a depressurized cabin for more than six minutes and suffered oxygen deprivation. For five out of the six minutes, the men experienced increased G-loads. The cabin pressure mounted like an avalanche. It is possible that in the first five seconds, the men suffered aerodynamic shock. The pressure was rising at the rate of 14 mm of mercury per second because the rate of vertical descent was 140-150 meters per second. There are grounds for believing that during the first three seconds the pilots became disabled, and then the uncontrolled descent. Gagarin and Seryogin simply had no time to regain consciousness and take over the controls again.
Kuznetsov said that the half-opened cock and the quick descent in diving was not the crew's fault. The cock could have been left open either by the technician or the pilot who flew the plane before Gagarin. The men acted strictly according to instructions, Kuznetsov said. And instructions did not restrict the rate of descent.
