By Georgy GRECHKO*, Dr. Sc. (Phys. & Math.), pilot-astronaut of the USSR In 1955, I began working as an engineer at the Experimental Design Office-1 with Sergey Korolev, and a year and a half later I was told to calculate a trajectory of guiding the first national satellite of the Earth into orbit. Namely, it was required to develop programs of pitching (angular movement of aircraft with regard to transverse) and characteristic speed so that a rocket would reach the first cosmic velocity with zero tilt over the local horizon. By that time the Americans had already madetwo attempts to launch such vehicles but they failed. However, we understood that there would be the third one soon, therefore, we had to hurry. Designers, "girls" as we called them, calculated this program under my direction using electromechanical machines (arithmometers but with electromotors). Of course, they were forty-fifty years old, however, at that time it was customary to address them so. Their first shift worked from 9 a.m. till 5 p.m.; then there was the second shift which worked from 6 p.m. till midnight. Then everybody left, and I could have a rest. But, as the next shift of designers came to work at 9 a.m., in order not to go far, I put on my coat and slept on my desk. This cycle was repeated every morning. Once an interesting thing happened to us. It is very difficult to select proper programs, so that the rocket would go out at a given point with zero tilt to the horizon: in the calculations it flew over it either with "plus", or "minus"; we had to use the method of successive approximations. The machines we used could not calculate trigonometric functions, therefore, we had to calculate them arithmetically. Suddenly, it was found out that we took the required functions from Khrenov's table, where trigonometric functions were specified with eight characters after a comma. At first, the designers went berserk: How come? We have always calculated according to B ... Read more