Friday, April 12, 2013


Yuri Alexevich Gagarin
First Man in Space
It was a political act. It had little to do with piloting. It was a dangerous stunt that almost cost a man his life, but it was the moment that began all manned spaceflight that followed. Fifty-two years ago today, Yuri Gagarin was strapped into an eight-foot-wide, aluminum-alloy sphere and launched into Earth orbit.

Gagarin was a tiny fellow, barely 5' 2". He was assigned the mission mostly because he didn't add much to the payload of the automated spacecraft. Sergei Korolev, the Chief Designer of the Soviet space program, said a final command to him before Gagarin climbed into the spacecraft: "Come back."

The ship Gagarin rode into space was called Vostok, which means "East" but also carries the idea of "Dawn" - - the beginning of a new day. The Vostok wasn't originally designed as a crewed spaceship - - Korolev's engineers based its construction on the requirements for a reconnaissance satellite, capable of hoisting several hundred pounds of cameras, lenses, and film into orbit. The ship was supposed to counter the American Corona project, which was already returning miles of photographic intelligence about Soviet air bases back to the CIA. Korolev managed to tack on the manned aspect of Vostok as a selling point to the Soviet politburo, who liked the secondary role for what it was: a great tool for propaganda about "space exploration," while concealing Vostok's primary purpose as a spy ship.

1:4 scale model of Vostok at the Kansas Cosmosphere.
Service Module at left, Descent Sphere at right.
Because Vostok's chief purpose was for unmanned missions, the control and operation of the ship was entirely automatic. A cosmonaut's role as pilot, then, was superfluous. Korolev worried about "interference" by pilots during flight, so the onboard controls were locked down with a password. As a compromise between the designers and the flight controllers, the ship carried a sealed envelope containing the manual override code. Cosmonauts were forbidden to open the envelope without approval from the mission operators back on Earth. I'm not exactly sure how they would stop a cosmonaut from opening the envelope.

Launch Day

On the morning of April 12th, 1961, Yuri Gagarin rode a bus to the base of the R-7 rocket that would launch his Vostok into the sky. He saluted Korolev, shook hands with several ground support personnel, and then climbed a ladder up to the Vostok's hatch. The ground team screwed on the hatch, and then needed to remove and reseat the hatch when they noticed it hadn't quite sealed properly. At 8:07am local Baikonur Time, the twenty engines of the R-7 Semyorka booster ignited, and Gagarin's ship lifted off the pad. He shouted "Поехали!" ("pyoucali!" or "Let's go!") into his microphone as the ship cleared the launch site.

Six minutes after launch, both the boosters and the protective cover around Gagarin's ship separated from Vostok 1. The cosmonaut's first opportunity to view the Earth from space revealed a cloud-covered morning over central Russia. "I can see the Earth. The visibility is good. I can almost see everything. There's a certain amount of space under the cumulus cloud cover," he reported back to Baikonur before flying out of radio range.

Unlike the American network of ships and ground stations spread across the world, the Soviet program had only a small group of ships scattered along Gagarin's intended flightpath. With limited data being returned to the control site, Korolev's people weren't sure if Vostok was in a stable orbit for nearly a half hour after launch.

Things were equally mysterious for Gagarin. Since he had only a few instruments to inform him about his ship's status, Gagarin could only rely on whatever information the ground controllers could radio to him during the brief moments when they were in touch via the relay ships. As he flew within communications range of a radar station in southeastern Siberia, Gagarin asked,  "What can you tell me about the flight? What can you tell me?" The station radioed back that they had nothing to report and that Korolev (code-named "Number Twenty") had no instructions for him. Vostok-1 continued its flight as it headed down the length of the Pacific Ocean.

At the half-way point over the Straits of Magellan, the Vostok attitude control system identified the Sun rising in the eastern sky. The ship aligned itself for retrofire, arming the service module's sole remaining engine. Korolev's mission designers had an unusual backup plan in the event of the rocket's failure during reentry: the selected orbit would decay naturally in 7-10 days, so they loaded Gagarin's crew module with a week's worth of food and oxygen to wait out the "organic" landing mode.

Fortunately, the retrorocket ignited successfully, chopping the orbital parameters to intersect with a ground track down to Siberia. Immediately after retrofire, though, came the mission's greatest failure. The service module containing the navigation and propellant equipment failed to detach from the descent sphere. As the upper atmosphere began to buffet the two modules, the sphere began to whip around the service module at an ever-increasing rate. Gagarin was experiencing more than 8 g's of lateral force, compounded by the deceleration effects of the atmospheric reentry. Ground controllers lost contact with the ship as it passed over Egypt. They wouldn't be able to communicate until the Vostok ship passed through the ionization layer.

Ejection tube of Vostok ship.
Kansas Cosmosphere
The buffeting snapped the connection between the service and descent modules, and Gagarin's ship managed to right itself to deploy the ship's parachute. As the ship approached an altitude of 23,000 feet, the cosmonaut ejected from the descent module, just as cameras and film would be jettisoned on unmanned reconnaissance missions. Gagarin descended separately from his ship because Korolev's spacecraft designers couldn't figure out how to build a parachute capable of landing both payload and ship safely. It was an embarrassing compromise for Korolev, and this aspect of the mission plan was kept from the West for decades.

In the Saratov region of western Siberia, two farm girls saw a pair of parachutes descending overhead. A man suspended by one of the parachutes landed on a nearby hill. Dressed in an orange suit with a large white helmet, the farm girls began to back away as he approached. They had heard about the American pilot Gary Powers and didn't want to be involved with another spy pilot. "Don't be afraid!" yelled Gagarin, lifting his visor. "I'm Russian!" Gagarin's  25,000 mile flight ended on a Siberian farm a little more than an hour and a half after it began.

Fifty two years later, the world celebrates the birth of manned spaceflight with Yuri's Night, a series of parties and star-gazing that anyone is free to join in and participate. Although Americans tend to ignore the achievements of other nations in space, this is truly an international event to appreciate. Gagarin's quick jaunt into space motivated Americans to reach for the Moon, and built the foundation for the world's cooperative program: the International Space Station. Go and enjoy Yuri's Night tonight, and think about the little guy who took that first flight.

No comments:

Post a Comment