Soyuz spacecraft dock in space
The Soyuz 7K-OK No. 5 (Baikal) (passive vehicle) lifted off on Oct. 30, 1967, at 11:12:46 Moscow Time from Site 1 in Tyuratam. It was officially announced as Kosmos-188. For the next hour, the flight control team had little to do but wait. The two ships conducted their pioneering maneuvers while crossing the Pacific, the Atlantic and then Africa, unheard by mission control.
Kosmos-186 (7K-OK No. 6) and Kosmos-188 (7K-OK No. 5) docked (almost) in orbit.
Kosmos-188 target vehicle No. 5 joins its counterpart in orbit
The Soyuz 7K-OK No. 5 (Baikal) (passive vehicle) lifted off on Oct. 30, 1967, at 11:12:46 Moscow Time from Site 1 in Tyuratam. It was officially announced as Kosmos-188. It was the same spacecraft, whose launch with three cosmonauts onboard had been canceled the previous April in the wake of problems aboard Soyuz-1.
During Orbit 49 (for the first ship), the ballistic calculations center in Bolshevo, near Moscow, reported that the ships were within the required 25-kilometer "window" from each other and that the distance between the two showed no tendency to increase rapidly. The incredible precision of the second launch meant that the radar of the active ship had immediately homed in on the signal of the radio beacon from the newly launch passive vehicle and the actual rendezvous process could begin immediately. According to one source, the actual distance between the two ships did not exceed 10 kilometers! (201)
As Chertok and his "co-conspirators" had previously planned, Agadzhanov directed his controllers to activate the rendezvous sequence. The USSR easternmost ground station, NIP-15, in Ussuriisk in the Soviet Far East transmitted the necessary commands to the spacecraft, as the pair was about to drift out of range over the Pacific Ocean. Chertok also informed Mishin and Kerimov about the decision, but instead of the expected reprimand, he heard a nod of approval.
For the next hour, the flight control team had little to do but wait. The two ships were supposed to conduct their pioneering maneuvers while crossing the Pacific, the Atlantic and then Africa, unheard by mission control. (466) Apparently, shortly before the ships went out of range, the last telemetry data signaled "drop in homing-in." "I knew you wouldn't be able to do it," General Yakov Tregub reportedly told to one of the Igla engineers V. Suslennikov and slammed the door behind him. (201)
Understanding the odds facing the mission, the flight team braced for failure. Engineers comforted themselves with the thought that they would not get too much flak for failing in the first attempt at such a complex experiment.
The mission control team hoped to get the earliest news on the status of the mission via short waves, which have the property of bouncing off the ionosphere and therefore enable over-the-horizon communications. Unfortunately, the shortwave radio was prone to interference and could transmitted only limited data.
Not surprisingly, the reception in short waves turned out to be very fragmentary in this case as well. Yet, as the clock was ticking, the developer of the shortwave system, Viktor Raspletin, stuttering from excitement, whispered to Chertok that it appeared that the spacecraft had docked. Mindful of a premature celebration, engineers decided to wait until the ships reappeared over the horizon. When Agadzhanov announced five-minute readiness for the next communications session, the main conference room occupied by the GOGU team was crowded with people.
They are docked!
As the crucial moment approached, Agadzhanov requested via an intercom system that Colonel Rodin from the telemetry service report immediately. The NIP-16 ground station in Crimea was the first to hear from the two ships approaching from the west.
"There is an indication of grapple and docking," one telemetry specialist reported looking at freshly printed telemetry tapes. A moment later, Petr Bratslavets screamed: "They are docked!" Loud applause exploded in the room.
A more detailed analysis of the telemetry then showed that the docking had been achieved at the margins of allowable parameters and that the proper berthing of the two vehicles had never been completed. There was some gap between the docking ports preventing the physical engagement of the electric interfaces on the two ships.
In the evening of October 30, Mishin, Kerimov, Feoktistov, Kamanin and Gagarin flew to Crimea from Tyuratam. At the joint meeting of the State Commission, excited engineers presented their reports based on the latest flight data that they had been able to decipher.
According to the latest information, the ships had spent 127 seconds conducting mutual attitude control adjustment, essentially turning toward each other. At the same time, the ships were also moving away from each other at a rate of 90 kilometers per hour. The Amur had to reverse the drift and begin the approach with the help of the SKD engine, while keeping the passive Baikal spacecraft within its radio range. Amur made more than 30 turns and 28 firings with the SKD engine. At a distance of 350 meters, the rendezvous process automatically switched to a slower berthing mode, which required 17 firings of the DPO thrusters. The entire rendezvous lasted just 54 minutes, but the active ship severely overspent the propellant for the SKD main engine and the DPO thrusters.
At the moment when the drogue of the active docking port hit the cone of the passive vehicle, the Igla rendezvous system was switched off. After the initial mechanical capture, the tightening of the two vehicles began, but the telemetry clearly registered that the berthing had not been completed. According to estimates made by docking experts, the ships were just 85 millimeters apart. However, TV images from orbit confirmed that the two spacecraft were in hard mate.
After all the tribulations and the tragedy of the past several months, the Soviet manned space flight team had finally a major accomplishment to celebrate.
Still in a triumphant mood, engineers formed several working groups to investigate the abnormal operation of the Igla system and the Rendezvous Control Unit, BUS. Another group working with the actual hardware at the production plant had to try to simulate what could have prevented the two vehicles from a complete docking. (466) According to one source, the in-depth investigation ultimately showed that as the two spacecraft had met up, they still had had a considerable side motion relative to each other, which probably caused the drogue of the active ship to physically bend as it engaged the cone receptacle of the passive ship. As a result, the full docking of the ships turned out to be impossible. (231)
Because a prolonged flight with a partially docked vehicles had been considered risky, mission control commanded the two ships to undock after two orbits in joint flight. The controllers then watched on live TV as the vehicles were moving apart. (466)
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Pavel Agadzhanov was the leading manager at mission control during the first automated rendezvous of the Soyuz spacecraft.
A meeting of the GOGU mission control team at NIP-16 in Crimea.
TV images of the Soyuz docking.
Live images of docked Soyuz spacecraft appeared in mission control, shortly after the two ships had entered the communications range of the Soviet ground stations.