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Gagarin orbits the Earth aboard Vostok

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Milestones of Gagarin's historic mission and approximate geographic locations of key exchanges between the world's first cosmonaut and ground control. Notable are repeated and fruitless attempts by Gagarin to get data on the parameters of his orbit from the Zarya 3 ground station in the Soviet Far East and the apparent unwillingness of rank-and-file controllers to share even the most basic and potentially life-saving information with the cosmonaut until permission from their superiors finally came later during the flight. Also ironic is the fact that at 10:18, a ground controller already addressed Gagarin as "Major," contrary to later jokes that Sr. Lieutenant Gagarin was promoted to Captain for the launch and to Major for the landing.

In orbit

Although all these details would become clear later, Gagarin and his peers on the ground perfectly understood the importance of entering the correct trajectory. The transcripts of radio communications between Gagarin and the Zarya 3 ground station in Elizovo in the Kamchatka Peninsula in the Soviet Far East, reveal repeated attempts by the cosmonaut to get confirmation on the parameters of his orbit. At one point Gagarin seemingly lost his patience, as he was stonewalled by meaningless replies and questions about his condition by a ground controller, who was either unable or unwilling to provide useful information:

Kedr (Gagarin): Calling Zarya 3, how do you hear me?
Kedr: Zarya 3, how do you hear me, how do you hear me? Do not hear Vesna (short-wave ground station), do not hear Vesna.
Zarya 3 (Karpenko): Understood; we can hear you satisfactorily.
Kedr: The flight is going well, everything is going well. What can you tell me?
Kedr: The flight is proceeding successfully. Feeling of weightlessness is normal. Feeling good. All instruments, the whole system is working well. What can you tell me?
Zarya 3 (Karpenko): Hear you well, instruments work well, feeling well.
Kedr: Hear you perfectly. What can you tell me about the flight? What can you tell me?
Zarya 3 (Karpenko): Instructions from the 20th (Korolev) have not been received. The flight is going well.
Kedr (Gagarin): Understood, there were no instructions from the 20th. Report your data about
the flight!
Say hello to Blondie (a reference to his fellow cosmonaut Aleksei Leonov stationed in Elizovo).
Zarya 3 (Karpenko): How do you hear me?
Kedr: Hearing you well. And you?
Zarya 3 (Karpenko): How are feeling?
Kedr: I am feeling outstanding, perfect, perfect, perfect. Tell me results on the flight!
Zarya 3 (Karpenko): Repeat, can't hear well.
Kedr: I am feeling very well, very well, well.
Kedr: Report me your data about the flight!
Zarya 3 (Karpenko): How do you hear me?.. (465)

The ground controller's reference to the lack of instructions from Korolev provides a hint about his fear to give out any data without explicit permission from top bosses. Korolev's rage toward his misbehaved subordinates is legendary. (Not to mention that Soviet history, from the Nedelin disaster to the Chernobyl accident, is full of examples, when the life-saving information was withheld for the sake of paranoid secrecy or the overwhelming fear of higher-ups.) However, it is also possible that despite all the planning, mission controllers simply lacked reliable orbital parameters by the time Gagarin's spacecraft appeared within the range of Elizovo, just 20 minutes after liftoff.


A Vostok flight control room around the time of Gagarin's flight.

The official history of the Russian ground control network claims just that:

...This triumphant mission had encountered unacceptable problems, which became a source of deep concern or even stress (among flight controllers). It happened when a single short-term interruption of Korolev's UHF communications with the cosmonaut took place during the transition of the spacecraft from the range of the Sary Shagan ground station to the Kolpashevo site... It also happened when the regional flight control team led by future cosmonaut Aleksei Leonov did not receive data from the Coordination and Calculation Center in Moscow about the actual orbit of Vostok by the time of contact with Gagarin. At the time, Leonov, so as not to worry Gagarin, took the responsibility on himself of telling the cosmonaut that the orbit was normal. It could not be farther from the truth... It also happened, when the operator of the command station in Kamchatka, sent a single command to the spacecraft to activate the PVU (the PVU Granit timer for the braking maneuver) without taking into account the yet-to-be calculated actual orbit... (270)

The last statement is especially controversial, as according to many reliable sources (466), the activation of the PVU Granit timer was triggered by the separation between the spacecraft and the third stage, not by a command from the ground. However, given the influence of the final orbit on the accuracy of the landing, a ground command to activate the device seems logical. At least one reliable source describing unmanned Vostok launches, which were essentially dress rehearsals for Gagarin's flight, referred to the testing of the transmission of flight control commands to the spacecraft.

In any case, half a century after Gagarin's flight it was still unclear how informed Gagarin and ground control were about the flight orbit, by the time Vostok left the range of the Elizovo ground station and plunged into darkness over the Pacific Ocean. We also know little about when this situation dawned on mission officials. Clearly, many of the details became known only after Gagarin's landing.


Yuri Gagarin on a TV image apparently recorded on the ground during the flight.

In the meantime, after Vostok had gone out of range of the Elizovo's UHF receivers, voice communication with the cosmonaut could only be maintained via short wave stations in Khabarovsk (in the Soviet Far East) and later in Moscow. According to Gagarin, short wave communications were very poor, until his spacecraft reached the apogee of its orbit over the night-covered Southern Pacific. (465)

Gagarin missed his first orbital sunset and only realized it when it was no longer possible to see any features outside the spacecraft, besides occasional stars. With his windows filled with darkness, he started making entries into the flight journal, while still wearing his spacesuit gloves. (469) He then let the writing pad float weightlessly to take a break for a much debated snack in space. He found no problems either eating or drinking, however when he picked his journal again, the pencil attached to it by a string was missing. He then made the decision to rewind his voice recorder, which had ran out of tape before the sunset. Its sound-activated mechanism turned out to be too sensitive to the loud noise of fans and other mechanisms in the cabin and used up the tape too quickly. Gagarin partially rewound the tape and re-started his narrative with manual activation of the recorder. As a result, a segment of his earlier recordings was erased.

Around 09:50, Gagarin confirmed the activation of the attitude control system which had the task of pointing Vostok tail first for the braking maneuver. Gagarin noticed that the tumbling of the spacecraft had slowed down, as small jet thrusters were stabilizing the vehicle.

Only around the tip of South America, as Vostok was near the highest point of its orbit, did Gagarin notice improvement in communications via short-wave radio. Unknown to him, at 09:53, transmitters of the Vesna short wave station in Khabarovsk had been activated on explicit orders from General Kamanin with the goal of finally assuring Gagarin that his spacecraft was in the planned orbit and that the flight was proceeding normally. (465) (Again, it is still unclear if this misleading message was a ploy to give Gagarin a psychological boost or the result of a blissful ignorance on the part of mission managers.):

Vesna (Kadushkin): The flight is proceeding normally, the orbit is as calculated.

Kedr (Gagarin): Understood: the flight is proceeding normally.

As Vostok's orbit crossed from the Pacific into the Atlantic, Gagarin was determined not to miss the sunrise. At the right time, he stared into the Vzor window. He saw a bright orange arc suddenly light up the horizon. The bottom edge of the arc then smoothly transitioned into blue via every color of the rainbow and then into black, as the surface of the Earth was still in darkness.

As the Sun appeared over the horizon, the flight control system obtained an exact reference for the orientation of the spacecraft for landing. Gagarin felt the spacecraft pitching and yawing, as the attitude control system was "catching" the Sun into the main sensor. Vostok was then ready for the deorbiting maneuver. (230, 231)

At 10:02, Moscow radio finally made the long-awaited announcement about the flight. Given the original intention to announce the launch within 20 minutes after the fact, it is still unknown whether the delay was the result of red tape or due to scrambling to confirm orbital parameters.


The Vostok 3A No. 3 mission timeline:

Time (planned)
Time (actual)
Stage I separation (T+119 seconds (51))
Payload fairing separation (T+154 seconds (51) T+150 seconds (465))
Stage II separation (T+299 seconds (51))
Spacecraft separation from Stage III
09:18:28* (463)
Spacecraft orientation relative to the Sun
Braking engine ignition
10:25:48.2 (463)
Descent and service module separation
Disintegration of the antennas under heat of reentry
Ejection of cosmonaut from the reentry capsule
Touchdown of the descent module
10:48 (463)
Touchdown of the pilot
10:53 (463)

*or 09:18:07 (464)


Planned and actual orbital parameters during Gagarin's mission:

Perigee (lowest point)
Apogee (highest point)
Orbital period
Planned orbit (464)
180 kilometers
230 kilometers
Initial TASS post-launch announcement
175 kilometers
302 kilometers
89.1 minutes
Post-flight article in Pravda
181 kilometers
327 kilometers
The preliminary report on the launch results (463)
181 kilometers
372 kilometers
64.57 degrees
89.44 minutes
Block-E orbital elements from US radar observations (464)
190.6 kilometers
326.2 kilometers


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Page author: Anatoly Zak; Last update: April 8, 2016

Page editor: Alain Chabot; Last edit: April 8, 2011

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Flight journal (right) and ID of the International Aviation Federation, FAI, which Gagarin carried with him into orbit. Note the string for a pencil, which was lost during the flight. Copyright © 2001 Anatoly Zak


A demo version of the Vostok spacecraft, minus lower end of the instrument module. Copyright © 2011 Anatoly Zak


Gagarin tries space food as seen on a TV screen in mission control, however the footage was probably recorded during training.


Yuri Gagarin on a TV image apparently recorded on the ground during the flight.


A mission planning room around the time of Gagarin's flight.


Yuri Levitan, the famous Soviet radio announcer read the first public statement about Gagarin's launch on April 12, 1961.