so there would be official footage of the event. This included an acceptance speech by Gagarin. As an indication of the level of secrecy involved, one of the other cosmonaut candidates, Alexei Leonov, later recalled that he did not know who was chosen for the mission until after the spaceflight had begun. Preparations 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. Because of weight constraints, there was no backup retrorocket engine. The spacecraft carried 13 days of provisions to allow for survival and natural orbital decay in the event the retrorockets failed. The letters "СССР" were hand-painted onto Gagarin's helmet by engineer Gherman Lebedev during transfer to the launch site. As it had been less than a year since U2 pilot Gary Powers was shot down, Lebedev reasoned that without some country identification, there was a small chance the cosmonaut might be mistaken for a spy on landing. Automatic control 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. Prior to the flight, Kamanin and others told Gagarin the code (1-2-5) anyway. April 11, 1961 At Baikonur Cosmodrome on the morning of April 11, 1961, the Vostok-K rocket, together with the attached Vostok 3KA space capsule, were transported several kilometers to the launch pad, in a horizontal position. Once they arrived at the launch pad, a quick examination of the booster was conducted by technicians to make sure everything was in order. When no visible problems were found, the booster was erected on LC-1. At 10:00 (Moscow Time), Gagarin and Titov were given a final review of the flight plan. They were informed that launch was scheduled to occur the following day, at 09:07 Moscow Time. This time was chosen so that when the capsule started to fly over Africa, which was when the retrorockets would need to fire for reentry, the solar illumination would be