Part II : 1950 -1957
Emphasis on Hydrogen
 When the NACA 1957 Flight Propulsion Conference was held at the Lewis laboratory on 21-22 November 1957, it could have been called, as one member of the audience remarked, a conference on liquid hydrogen as a fuel. The primary emphasis was on air-breathing engines, but the rocket group had a sizeable part of the program-the last three of eight presentations.40 Silverstein had decided that rather than having individual papers, each subject would be handled by a panel taking turns presenting the subject and discussing it. The subjects were broad. The three on rockets were propellants, turbopumps for high-energy propellants, and performance and missions. The last two were firmly on the subject of high-energy propellants, but somehow the one on propellants got out of line. It covered the spectrum of propellants, with high-energy propellants receiving attention only at the beginning and at the end, and even then the emphasis was on cooling rather than performance. This emphasis on cooling was due to circumstances. Of the four panelists on propellants, only Howard Douglass was experienced in investigating high-energy propellants. Two of the panelists were newcomers to rockets; one was studying solid propellants, and the other was a controls specialist. It was characteristic of Silverstein to stimulate research by obligating the staff to a research conference with tight deadlines and by assigning individuals the responsibility of discussing subjects broader than their immediate research. Douglass had intended to cover high-energy propellants more thoroughly and add experimental results, but a series of delays in experimental operations almost caused his discussion to be all theoretical.