In the 1940's, Edward Parsons and John Forman were researching rocket engines and especially their fuels in all flight conditions.

-Both in atmosphere and in stratosphere.

-In the beginning, the nozzles were the object of special study due to the problems to adapt them from theory to real operation.

-In a way they were following Goddard's footsteps and tests.

“Parsons y Forman's rocket engine” (PiP=ps)