Vostok-3 and Vostok-4 and observations of their flight in radio intercepts

Sven Grahn


After the successful flight of Gherman Titov in August 1961, most observers expected the next Soviet manned spaceflight to be flown soon. Howeveer, the Korolev design bureau concentrated on getting the military spy satellite version of Vostok - Zenit - to work. However, when John Glenn flew in February 1962 the Soviet leadership suddenly asked Korolev to launch the next space spectacular promptly. But there were problems with Zenit and only one operational launch pad at Baikonur for this type of launch vehicle. This delayed the first group flight until August. The notion of a group flight had been advanced in the months after Vostok-2. Initially the idea was to fly three spacecraft, but  soon a consensus was reached to fly two vehicles. The final decision on the flight duration was taken as late as 18 July 1962 when the two flights were aimed at lasting "up to three days". That the flights lasted four days was due to a decision taken during the flight by Khruschov himself. (8)

Friday 10 August 1962

During the evening of 10 Aug 1962 rumors started among journalists in Moscow that a space spectacular was imminent. Soviet journalists had been told to watch the radio news closely in the days to follow. A much longer flight than that of Vostok-2 was one possibility mentioned, but also the launch of two cosmonauts. (9)

Saturday 11 August 1962

Vostok-3 was indeed launched from Baikonur at 0830 UT on 11 August 1962 carrying cosmonaut Andriyan Nikolayev.

In Sweden, the Telecommunications Administration monitoring station at Enkoping near Stockholm picked up Vostok-3 (1). Beacon signals on 19.995 MHz were picked up by operator Alf Svensson (see picture on the right) at 1303 and 1432 UT.  At 1606-1608.30 UT the following conversation was picked up on 20.006 MHz by the same station:

"....in eight minutes the fifth revolution will be completed... Vesna 1, ya Sokol (Eagle) I give you some data; the time is now 1908...one and one,, and and two..temperature 203, I feel fine..."

More beacon signals were picked up on 19.995 MHz at 1734 and 1905-1913 UT.

Sunday 12 August 1962

Vostok-4 with Pavel Popovich was launched from Baikonur at 0802:33 UT and Moscow promptly released the news to the world. At 1236 UT he was heard talking on 20.006 MHz by the Telecommunications Administration monitoring station at Enkoping and beacon signals from Vostok-4 were picked up at 1842 UT (2).

Monday 13 August 1962

Beacon signals from the spacecraft were picked up by Telecommunications Administration monitoring station at Enkoping  at 0738, 1037, 1207,1338 UT. Some voice was heard at 1509 UT followed at more beacon signals in the evening; on 19.995 MHz at 1939 UT and on 19.990 MHz at 1942 UT. The Japanese monitoring station at Chiba reported that they had heard ground stations order the cosmonauts to prepare for descent (2), but Moscow denied all rumours of an imminent landing.

A greeting to the Scandinavian peoples was sent from Vostok-3 at 1338 UT (3) and picked up by Terje Isberg in Danderyd outside Stockholm (6). the message read: ".. From the Soviet space ship Vostok-3   I send a greeting  and the best wishes to the Scandinavian peoples. Cosmonaut Nikolayev....."

Tuesday 14 August 1962 - Vesna 1 and Sokol quarrel!

Starting at 1301 UT the following exchange between cosmonaut Nikolayev and the ground was picked up by Telecommunications Administration monitoring station at Enkoping (4) (click here to see map of this pass over Sweden):

".....Vesna 1, ya Sokol. You have made an error of five minutes at your latest time report. I have checked and the time was not 1512 Moscow Time as you said but rather 1507. Now, give me a new time. Can't you hear me? I hear you very well, Now get started with your time report. No, now you are getting it wrong again! You do not do this the right way! Now listen to me! Listen, I said! I will teach you how to do this perfectly. Correct time is 1609..1609...1609.. attention! (Vnimanie)....now (otchet)!....Vesna 1- that was a correct time report, wasn't it? That's is the way to run the show and not in the sloppy way that you did. Vesna 6 gave me correct time at 1529 and they knew how to do it. Please convey my thanks to Vesna 6. Their  time report was really good.... Yes, OK, your time report is correct now, thanks ... Here on board all is well. The cabin pressure is 1 and 1, temperature 12, humidity 72, pressure in the instrument section 1 and 2, pressure in the manual system is 70 and in the automatic system: first 145, second 130. As for myself, I feel excellent. Everything is working out precisely as we planned. Cheerio (privet)..."

At 1607 UT the Vostok-4 beacon on 19.989 MHz was heard. At 1609 UT cosmonaut Nikolayev was again heard on 20.006 MHz talking to "Vesna 1":

"....Vesna 1, ya Sokol how do you read me? I will relay some instrument readings. Pressure in the catapult system is 300.. I have been in touch with Golden eagle (Berkut) at the southern point. At this moment I have no contact with Berkut...". This was the first time that Sokol mentioned the catapult!

At 1620 "Sokol" can be hard calling "Vesna 4" saying that "I am concentrating on point 20 in the flight plan". Thereafter he calls Vesna 7. Beacon signals from Vostok 4 were heard on 19.990 MHz at 1735-1800 UT.

Wednesday 15 August 1962

After a flight of four and three days respectively, it was time to come down for the two spacefarers. The landings took place very far to the east, so it was not entirely easy to follow the landing phase through radio receptions.

Beacon signals on 19.995 MHz (i.e. from Vostok-3) and weak voice on 20.006 MHz appeared at 0628-0632 UT, At  0652 the word "...Three...three..." were heard in Russian and at 0715 the word "Attention" (Vnimanie)! was broadcast on this frequency.

At 0741 UT Radio Moscow announced that an important message would soon be broadcast and after intermission music radio announcer Yuri Levitan's booming voice appeared at 0748 UT (5) to announce the landing of both ships.

Andriyan Nikolayev landed in Vostok-3 at 0652 UT on 15 August 1962 at 48.03 degrees North, 75.75 degrees East. Pavel Popovich landed in Vostok-4 at 0659 UT on 15 August 1962 at 48.17 degrees North, 71.85 degrees East. The Vostok-3 retrorocket had ignited at 0624 UT and that of Vostok-4 six minutes later. (7)

It is interesting that they both landed on the same parallel, the 48 th. For Vostok 5 and 6 the same principle was used, but the landing was made on the 53 rd parallel. Perhaps the idea was to deploy recovery forces in an east-west pattern? Later, during fights of the Zenit reconnaissance satellite landings were made roughly along the 52 nd parallel (See Landing zones for Zenit-2 missions).

Why was nothing heard from Vostok-4?

It is interesting to note that all reports about the reception of voice signals from the mission mention only Nikolayev ("Sokol") talking to the ground on 20.006 MHz. Popovich ("Berkut") is never heard from on this channel even though it was said to be used also by Vostok-4 according to TASS. However, a revealing indication is given in (7): "The radio equipment aboard the spacecraft included three two-way radio-telephone lines, two in the shortwave band and one in the ultra-shortwave band". Two shortwave voice channels? Only one frequency is mentioned by TASS! So, perhaps Vostok-4 operated on an unannounced shortwave frequency? The "ultra-shortwave" frequency mentioned is of course 143.625 MHz.

Did they talk to each other?

The spacecraft orbited at about 170 km at the end of their missions and at that altitude the distance to the horizon is 1482 km. Near the end of the mission they craft were 2800 km from each other, so they were virtually at each other's horizon. Therefore during the flight they were within line-of-sight of each other. In (7) there is an "inter-ship channel" mentioned This channel seems to have been in the shortwave band because in (7) we can read: "Communications in the shortwave band were quite successful both along the main earth-ship-earth channel and in listening on the Earth to the ship-to-ship channel" (my emphasis). Clearly, the two crew members talked to each other.

How close did Vostok-3 and -4 come?

I have looked up the Vostok-3 and -4 element sets on NASA's web site for orbital information and I must conclude that the data is utterly unreliable when it comes to determining the distance between the spacecraft. The elements seem to have been reconstructed from Soviet data and perhaps spotty radio observations made elsewhere. The NASA elements for Vostok-3 match radio observations quite well, but the element set at launch for Vostok-4 is the same as that for Vostok-3 that same morning, which is not correct. The two spacecraft were injected into orbits with different orbital periods.

The distance between the spacecraft given by Soviet sources (7) is probably quite accurate concerning the distance between the spacecraft days after the launch of Vostok-4. The graph on the right is entirely consistent with the differnce in orbital period of 0.13 minutes given by the same source. The same source gave the initial distance between the ships as 6.5 kilometers. There is no way to check this number, but there is also no reason to doubt it.


  1. Swedish Daily "Dagens Nyheter", 12 August 1962, p. 8
  2. Swedish evening paper "Aftonbladet", 13 August 1962, p. 6-7
  3. Swedish Daily "Dagens Nyheter", 14 August 1962, p. 7
  4. Swedish Daily "Dagens Nyheter", 15 August 1962, p. 6
  5. Swedish Daily "Dagens Nyheter", 16 August 1962, p. 8
  6. Private communication by e-mail from Terje Isberg, 14 March 2000
  7. Conquest of Cosmic Space by the USSR,  official TASS communiques and material from the central press, 1957-67, Nauka Publishers, Moscow 1971, p. 400-401.
  8. Bart Hendricx, "The Kamanin diaries 1960-63", JBIS, Vol. 50, No.1, January 1997, p.36
  9. Swedish Daily "Dagens Nyheter", 11 August 1962


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