Tuesday, April 12, 2011

Commemorating the 50th anniversary of mankind's first steps into space

 Vostok 1 Mission Insignia

Vostok 1 was the first known spaceflight in the Vostok program and the first known human spaceflight in history. (Vostok is Russian for “Orient” or “East”; I presume it was so named because spacecraft are launched on an easterly trajectory to harness the rotational force of the Earth)  The Vostok 3KA spacecraft was launched on April 12, 1961.  The flight took Yuri Gagarin, a cosmonaut from the Soviet Union, into space, marking the first time that a human entered outer space, as well as the first orbital flight of a manned vehicle.  Vostok 1 was launched by the Soviet space program, and was designed by Soviet engineers guided by Sergei Korolyev under military supervision of Kerim Kerimov and others.
 In case you forgot who the Soviet Union was.

The spaceflight consisted of a single orbit of the Earth.  According to official records, the spaceflight took 108 minutes from launch to landing.  As planned, Gagarin landed separately from his spacecraft, having ejected with a parachute 7 km (23,000 ft) above ground.  Due to the secrecy surrounding the Soviet space program at the time, many details of the spaceflight only came to light years later, and several details in the original press releases turned out to be false.

 Yuri, Yuri, you're the cosmonaut for me

27 year-old Yuri Gagarin was the only crew member of Vostok 1.  The Vostok spacecraft were designed to carry a single cosmonaut.  The primary and secondary backup cosmonauts for the mission were Gherman Titov and Grigori Nelyubov.  The assignments were formally made on April 8, four days before the mission, but Gagarin had been a favorite among the cosmonaut candidates for at least several months.

Unlike later Vostok missions, there were no dedicated tracking ships available to receive signals from the spacecraft.  Instead, they relied on the network of ground stations, also called Command Points, to communicate with the spacecraft; all of these Command Points were located within the Soviet Union.  This meant that communication with the craft was not always clear, and telemetry data were not immediately available.  Also, because of weight constraints, there was no backup retrorocket engine.  The spacecraft carried 10 days of provisions to allow for survival and natural decay of the orbit in the event the retrorockets failed. 

The entire mission would be controlled by either automatic systems, or by ground control.  This was because medical staff and spacecraft engineers were unsure how a human might react to weightlessness, and therefore it was decided to lock the pilot's manual controls.  In an unusual move, a code to unlock the controls was placed in an onboard envelope, for Gagarin's use in case of emergency.  But, prior to the flight, one of the mission controllers told Gagarin the code anyway.
 Strap a rocket on this badboy, and you're ready for launch!  
(pretty much literally)

On the morning of April 11, 1961, the Vostok-K rocket, together with the attached Vostok 3KA spacecraft, were transported several miles to the launch pad, in a horizontal position.  Once they arrived at the launch pad, Sergei Korolyev inspected the rocket and spacecraft for problems, and without finding any, the rocket was raised into the upright position.  At 10am (Moscow time), Gagarin and Titov were given a final review of the flight plan.  They were informed that launch was scheduled to occur at 9:07am Moscow time.  This time was chosen so that when the spacecraft started to fly over Africa, which was when the retrorockets would need to fire for reentry, the solar illumination would be ideal for the orientation system's sensors.

At 5:30 a.m. Moscow time, on the morning of April 12, 1961, both Gagarin and his backup Titov were woken.  They were given breakfast, and assisted into their spacesuits.  One of the onlookers in the dressing room semi-jokingly suggested that upon landing in his futuristic outfit Gagarin could be mistaken for the pilot of an American spy plane like the one that had been shot down over USSR in the previous year.  The idea was taken seriously and officials made the urgent decision to paint C C C P (USSR) on the front of Gagarin's helmet in big red letters.  A number of photos showing Gagarin in his helmet before and after the letters were painted confirm the aucenticity of the story.  One life-support engineer known for his calligraphic writing quickly accomplished the improvised task.  Gagarin reportedly pleaded with the "artist" to be careful not to drop red paint on his nose.  After transport to the launch pad, Gagarin entered the Vostok 1 spacecraft, and at 07:10 local time (04:10 UTC), the radio communication system was turned on.  Once Gagarin was in the Vostok 1 spacecraft, his picture appeared on television screens in the launch control room from an onboard camera.  Launch would not occur for another two hours, and during the time Gagarin chatted with the mission's main CapCom (the flight control “capsule communicator"), as well as Chief Designer Sergei Korolev, Nikolai Kamanin, and a few others.  Following a series of tests and checks, about forty minutes after Gagarin entered the spacecraft, its hatch was closed.  It was soon discovered that the seal was not complete, so technicians spent nearly an hour removing all the screws and sealing the hatch again. 

During this time Gagarin requested some music to be played over the radio.  Sergei Korolyev was very nervous in the lead up to the launch; he experienced chest pains, and took a pill to calm his heart.  Gagarin, on the other hand, was described as calm; about half an hour before launch his pulse was recorded at 64 beats per minute.  Gagarin's launch vehicle blasted off into the cloudless blue sky almost as scheduled, just a fraction of a second before 09:07 Moscow Time.  Several thousands of military officers, soldiers, technicians and engineers spread over various facilities of the top-secret test range later known as Baikonur witnessed the roaring vehicle rising over the steppe and heading eastward.

 Orbital path of Vostok 1

Fortunately for Gagarin, his liftoff and the ride to orbit went smoothly. Inside the spacecraft, Gagarin felt how the heavy pressure of g-loads pressed him into the seat, stiffening his legs, arms and face and making it difficult to talk.  One minute after launch the acceleration had reached 3-4 g and Gagarin's pulse rose from a regular 64 to 150.  According to Korolyev, around 13 minutes after launch, he had confirmation that the first man from Earth had reached the Earth's orbit.  The question remained, though, of what kind of orbit it was.

For decades, countless books repeated each other, claiming that Gagarin's launch was flawless.  Only by the end of the 20th century did the truth start to emerge.  Later calculations showed that Gagarin's orbit was 327 kilometers above the Earth's surface at its highest point (apogee), instead of the planned 230 kilometers.  Overshooting its apogee by almost 100 kilometers posed multiple and potentially deadly problems.  Since Vostok had no backup braking engine, its planned orbit was calculated to be low enough to allow the rarified air at that altitude to slow down the spacecraft so that it could reenter the atmosphere and land 5-7 days after launch without any additional thrust.  In preparation for the possibility that the sole retrorocket could fail, Vostok carried enough air, food and other vital consumables on board for a 10-day flight.  However, Gagarin's actual orbit would need more than two weeks (possibly as many as 30 days) to decay and allow the return to Earth.  Therefore, if the first cosmonaut's braking engine failed, he would be doomed to a slow death in orbit.  Even if everything else went as planned, the higher-than-normal orbit could still affect the flight.  Immediately after the separation from the third stage of the launch vehicle, a special timer called PVU Granit was activated onboard Vostok, counting down toward the firing of the braking engine.  Probably as a result of the higher (and consequently longer) orbit, the timer was now programmed to start the deorbiting maneuver slightly ahead of the correct point.  In turn, the premature reentry would shift Gagarin's touchdown point forward, short of its target.

While over the tip of South America, as Vostok was near the highest point of its orbit, Gagarin noticed 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.  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.  Also, 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.

As the sun appeared over the horizon for Gagarin, 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.  Everything looked good until the conclusion of the 40-second burn of the braking engine, initiated successfully at 10:25 Moscow Time.  Gagarin was expecting the separation of his reentry capsule from the instrument module to take place 10-12 seconds after the deorbiting burn (which would have been just as the craft began to pass over Africa); however, it did not take place.  In the meantime, the spacecraft continued tumbling wildly, as it approached denser layers of the atmosphere.  Despite this situation, Gagarin believed everything was on track for a safe landing, and when the separation finally did take place ten minutes later, the spacecraft was over the Mediterranean Sea.

For decades, the very fact, not to mention the cause, of the whole incident with the separation of the capsule and its instrument module remained unknown to the general public.  Even after Gagarin's mission report was published, at least one participant of the events denied any problems during the reentry and tried to explain the situation by Gagarin's confusion about the real time of the separation.  As it turned out, a single valve within the braking engine failed to shut completely at the beginning of the engine burn, letting some fuel leak out and avoid the combustion chamber.  As a result, the engine "ran out of gas" and shut down around a second earlier than scheduled.  The aborted maneuver slowed the spacecraft by 132 meters per second instead of the programmed 136 meters per second.  Even though it was enough to push the spacecraft off its orbit toward reentry, it was apparently not enough for the "punctual" flight control system to generate the nominal command to cut off the engine.  In the absence of a proper cutoff command, the propellant lines of the engine remained open, after it ran out of fuel and stalled.  As a result, the pressurization gas and remaining oxidizer continued escaping through the main nozzle and steering thrusters, causing the spacecraft to spin wildly.  Although the engine was later cut off by a timer, the lack of delivered thrust also caused the flight control system to scrub the primary sequence for the separation between the reentry vehicle and the instrument module.  Fortunately, the separation did take place some 10 minutes later, (around 10:35 Moscow time), supposedly, as a result of an emergency command.

As the spacecraft plunged into the atmosphere, Gagarin saw a bright crimson glow appear behind his windows.  It was accompanied by the crackling noise of thermal protection layers burning in the heat of atmospheric reentry.  Gagarin estimated that at their peak g-forces exceeded 10:
"There was a moment, about 2-3 seconds, when data on the control gauges started looking blurry.  It was starting turning gray in my eyes.  I braced and composed myself.  It helped, everything kind of returned to its place."
Potentially much more troubling and unexpected than g-loads was the burning smell in the cabin.  Fortunately, it was very slight and short-lived, according to Gagarin's recollections after the flight.

As G-forces subsided and the capsule continued descending safely, Gagarin prepared to eject from his craft.  At an altitude of seven kilometers, the main hatch of the capsule was jettisoned and seconds later, the pilot ejected.  The main parachute deployed successfully, however the backup chute came out later as well and, after some delay, deployed.  As a result, Gagarin landed under two parachutes.  For six minutes during the parachute descent Gagarin struggled to open a valve for breathing atmospheric air.  The device stuck below his external orange layer and he had to use a mirror to pull the valve.

Both he and the spacecraft landed via parachute 26 km (16 mi) south west of Engels, in the Saratov region.  A farmer and her daughter observed the strange scene of a figure in a bright orange suit with a large white helmet landing near them by parachute.  Gagarin later recalled, "When they saw me in my space suit and the parachute dragging alongside as I walked, they started to back away in fear.  I told them, don't be afraid, I am a Soviet like you, who has descended from space and I must find a telephone to call Moscow!"

Officially the U.S. congratulated the Soviet Union on its accomplishments.

The Soviet press later reported that minutes before boarding the spacecraft Gagarin made a speech: "Dear friends, you who are close to me, and you whom I do not know, fellow Russians, and people of all countries and all continents: In a few minutes a powerful space vehicle will carry me into the distant realm of space.  What can I tell you in these last minutes before the launch?  My whole life appears to me as one beautiful moment.  All that I previously lived through and did, was lived through and done for the sake of this moment." He actually recorded the speech—prepared by anonymous speechwriters—in Moscow.

Fédération Aéronautique Internationale (the world governing body for air sports and aeronautics and astronautics world records) rules in 1961 required that a pilot must land with the spacecraft to be considered an official spaceflight for the FAI record books.  At the time, the Soviet Union insisted that Gagarin had landed with the Vostok; the government forced the cosmonaut to lie in press conferences, and the FAI certified the flight.  The Soviet Union admitted in 1971 that Gagarin had ejected and landed separately from the Vostok descent module.  (cheating bastards)

 If you were the first person in space, this could have been yours.
The craft landing site is now a monument park.  The central feature in the park is a 25 meter tall monument that consists of a silver metallic rocket ship rising on a curved metallic column of flame, from a wedge shaped, white stone base.  In front of this is a 3 meter tall, white stone statue of Yuri Gagarin, wearing a spacesuit, and with one arm raised in greeting and the other holding a space helmet.

Not bad for a bunch of communists! 


  1. Yeah, it's a pretty amazing feat. It took a lot of work and cost a couple human lives though.

  2. I know this may sound stupid, but I read a manga once which stated that the Nazis were even the first to reach the moon. Of course this was a joke, and it worked :)

  3. I've always been interested in this. thanks!

  4. Great history lesson I always love learning :D

  5. going to read this when i'm at home, sounds interesting

  6. You are aware that Gagarin wasn't the first Soviet man in the space, right?
    He was the first to survive.

  7. Its pretty crazy when you think about how far we've come in such a short period of time.

  8. Shouldn't we have resorts on the moon by now?

  9. yuri is my hero, too bad he died so soon

  10. The corruption and back-room dealing done by both the US and USSR during the space race is kind of an interesting story now.

  11. I dont believe we ever made it to the Moon

  12. Very intriguing information. I will let this post digest and absorb it more over time. Thank you for sharing!