These records are from a multiple task effort pertaining to Jet Propulsion Laboratory's (JPL) safety related analysis of the Radioisotope Thermoelectric Generator (RTG) used on two NASA interplanetary investigations, the Galileo mission to Jupiter and the Ulysses mission around the poles of the sun. The RTG is a device that converts thermal energy produced by the radioactive decay of the isotope Plutonium 238 (oxide form PuO2), into electrical energy for spacecraft use, via Silicon Germainium unicouples, (thermocouple). Each Plutonium Oxide pellet is encased in an Iridium capsule which provides primary containment of the isotope. Two "Bare Clad" fuel pellets are placed in a Graphite Impact Shell (GIS). Two GIS's are inserted in a rectangular carbon/carbon composite Aeroshell. The Aeroshell unit is known as a General Purpose Heat Source (GPHS). There are 18 GPHS units in an RTG. The Breakup Analysis is part of a larger, more comprehensive, nuclear safety analysis which is required whenever an RTG is flown. The Breakup Analysis consists of the following subdivisions: 1. Determination of the aerodynamics of the reentry assembly. 2. Calculation of entry desceleration and heat transfer rates using the above aerodynamics. 3. Determine heat and dynamic forces on the spacecraft and RTG. 4. Determine structural responses of components subject to heat and stress forces. Once a component is predicted to fail, the process is repeated until the RTG is free of the spacecraft or the RTG itself is broken up and the GPHS modules are released. At this point an analysis of GPHS/bare clad fuel pellet and Earth impact is done. Solid rocket booster (SRB) and solid rocket motor (SRM) explosive fragmentation is analysed for fragment impingement on spacecraft/RTG and thereby causing breakup. This data is brought back into the iterative process. A principal in JPL's safety investigation and the source of these documents was Mr. Peter Jaffe, Sec. 354, Applied Mechanics Technologies. Contractors and other principals in the design, evaluation, and testing of the RTG units and peripherals are General Electric, General Dynamics/Convair, Sandia Laboratory, Los Alamos Laboratory, Johns Hopkins, Air Force Arnold Engineering Center, U. S. Army Ballistic Research Laboratory, Aerospace Research Laboratory, RDA Logicon, Martin Marietta, Fairchild, and NASA's Ames, Langely, and Lewis Facilities. The documents are a compilation of correspondence, drawings, exhibits (models), graphs, memoranda, notes, photographs, plans (procedures), reports, schedules, specifications, summaries, and tables. The dates of the material range from February 1962 through September 1990. The material is arranged topically but it is not in chronological order. The records are arranged in the following series: 1. Records relating to RTG safety, spacecraft and booster. 2. Accident models for RTG, spacecraft and boosters 3. Records describing explosions of solid rocket motors/boosters. 4. Aerodynamics of various shapes relating to RTG reentry. 5. Records relating to reentry heating and break up of Galileo / Ulysses or RTG. 6. Records relating to impact tests of heat source, bare clad fuel cells of RTG. 7. Computer documents: solid rocket fragments, RTG breakup, computer access.
