He knew that this made the rocket twist and turn. He figured out that liquid-fuel burns evenly and makes the rocket fly straight (Munch 18). .
In the mid 1950's, tests and studies were done to determine if Tsiolkovsky's theory that liquid hydrogen used as a propellent would be safe to use. One of the major concerns was the fire and explosion hazards of hydrogen, and the other concern was if it could be handled as safely as gasoline. Tests were done in which a tank containing liquid hydrogen under pressure, was ruptured. The tests showed that most often, the hydrogen escaped quickly without igniting. Another test used, was to place a small charge on two tanks. One tank contained hydrogen, the other tank contained gasoline. When the hydrogen charge was ignited, a large fireball erupted, but quickly dissapated; the gasoline however, clearly did much more damage when ignited. Therefore these tests proved that yes, with proper care, liquid hydrogen could be handled safely and would also reduce the chance of causing a worse problem if something on the rocket malfunctioned. (Nasa Internet, 1) (liquid hydrogen as a propulsi!.
on fuel).
Tsiolkovsky also is know for advancing the concept of multi-stage rockets (Bryan 355). A multi-stage vehicle is actually several rockets combined to form one large rocket. They are hooked together to form one large rocket. Each rocket carries its" own tanks containing the liquid fuel. The stages are burned one at a time, until their fuel is used up, or they have reached their pre-determined velocity. Then the empty rockets are released, and fall back to earth (Munch 39).
Dr. Robert H. Goddard, the last of the three great rocket pioneers, was the maker and successful launcher of the liquid-fuel rocket. He began his studies with extensive research of rocket dynamics. He started his research in 1909. On March 16, 1926, in Auburn Massachusetts, Dr. Goddard launched the world's first liquid-fuel rocket, which reached a height of 184 feet (Bryan 364).