By end of the 20s years and beginning of the 30s years of the last century, scientists tried to gather important information for space travel with balloon flights to the stratosphere and the only possibility to reach an altitude of around 20 km (stratosphere layer) was the use of the so called stratosphere balloons.
Some people in different countries like USA, Russia, Poland and Belgium have started this trials and have been partly successful for example Auguste Piccard but as well partly failed with total disaster and mortal accident of the complete crew.
The most famous and successful pioneer in that field was Auguste Piccard from Belgium , a great friend of Albert Einstein, well know as well for his reaserch work on job during his flights and his submarine activities.
He achieved on 18 of august 1932 with his successful flight launched in Dübendorf an altitude of 16.250 m with his colleague M.Cosins.
In the year 1933 USA and Russia started a competition to reach the highest altitude.
The russian Prokofiew, Birnbaum and Godunow (Balloon Stratosta UdSSR I) reached on 30.09.1933 19.000 m successful, but the other crew with the russian team Fedossenk, Wassenko and Usyskin (Balloon Ossoawiachim I ) failed with their mission and the complete crew died during landing procedure (reached altitude was 22.000 m, 30.01.1934).
The absolute record for that time have been realized by the USA team Stevens and Anderson (Balloon Explorer II ) on 11 of november 1935 by achieving 22.066 m.
Even today with the 40 km stratosphere balloon flight and jump from Felix Baumgärtner (Austria) in 2013 out of his stratosphere balloon, there is some further interest in that kind of flights and transferring the won informations and results to the current manned spaceflight development.
But of coure we should as well remember that the precursor of all balloonflights has been the trials of the 2 brothers Joseph Michel Montgolfier and Jacques Etienne Montgolfier with their first balloonflight (hot gas) on 21.11.1783 in France.
Stratosphere balloon flights all nations