---
title: "Jack Parsons"
chunk: 6/16
source: "https://en.wikipedia.org/wiki/Jack_Parsons"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:32:07.745794+00:00"
instance: "kb-cron"
---

For the JATO project, they were joined by Caltech mathematician Martin Summerfield and 18 workers supplied by the Works Progress Administration. Former colleagues like Qian were prevented from returning to the project by the Federal Bureau of Investigation (FBI), who ensured the secrecy of the operation and restricted the involvement of foreign nationals and political extremists. The FBI was satisfied that Parsons was not a Marxist but were concerned when Thelemite friend Paul Seckler used Parsons' gun in a drunken car hijacking, for which Seckler was imprisoned in San Quentin State Prison for two years. Englishman George Emerson replaced Arnold as the Group's official photographer.
The Group's aim was to find a replacement for black-powder rocket motors—units consisting of charcoal, sulfur and potassium nitrate with a binding agent. The mixture was unstable and there were frequent explosions damaging military aircraft. The solid JATO fuel invented by Parsons consisted of amide, corn starch, and ammonium nitrate bound together in the JATO unit with glue and blotting paper. It was codenamed GALCIT-27, implying the previous invention of 26 new fuels. The first JATO tests using an ERCO Ercoupe plane took place in late July 1941; though they aided propulsion, the units frequently exploded and damaged the aircraft. Parsons theorized that this was because the ammonium nitrate became dangerously combustible following overnight storage, during which temperature and consistency changes had resulted in a chemical imbalance. Parsons and Malina accordingly devised a method in which they would fill the JATOs with the fuel in the early mornings shortly before the tests, enduring sleep deprivation to do so. On August 21, 1941, Navy Captain Homer J. Boushey, Jr.—watched by Clark Millikan and William F. Durand—piloted the JATO-equipped Ercoupe at March Air Force Base in Moreno Valley, California. It proved a success and reduced takeoff distance by 30%, but one of the JATOs partially exploded. Over the following weeks 62 further tests took place, and the NAS increased their grant to $125,000. During a series of static experiments, an exploding JATO did significant damage to the rear fuselage of an Ercoupe; one observer optimistically noted that "at least it wasn't a big hole", but necessary repairs delayed their efforts.
The military ordered a flight test using liquid rather than solid fuel in early 1942. Upon the United States' entry into the Second World War in December 1941, the Group realized they could be drafted directly into military service if they failed to provide viable JATO technology for the military. Informed by their left-wing politics, aiding the war effort against Nazi Germany and the Axis powers was as much of a moral vocation to Parsons, Forman and Malina as it was a practical one. Parsons, Summerfield and the GALCIT workers focused on the task and found success with a combination of gasoline with red fuming nitric acid as its oxidizer; the latter, suggested by Parsons, was an effective substitute for liquid oxygen. The testing of this fuel resulted in another calamity, when the testing rocket motor exploded; the fire, containing iron shed fragments and shrapnel, inexplicably left the experimenters unscathed. Malina solved the problem by replacing the gasoline with aniline, resulting in a successful test launch of a JATO-equipped A-20A plane at the Muroc Auxiliary Air Field in the Mojave Desert. It provided five times more thrust than GALCIT-27, and again reduced takeoff distance by 30%; Malina wrote to his parents that "We now have something that really works and we should be able to help give the Fascists hell!"