This image shows the SNAP-19 RTG unit 111 in a fueled state. This image was taken November 22, 1974. Design and Testing for the RTGs was unique because their systems had to be shipped to the launch site 6 months in advance of the Lander Encapsulation. This resulted in a Design Test cycle deadline in advance of many other systems. This was complicated by the need to do environmental testing (food chain contamination analysis), biological testing, structural integrity testing, and many other tests as a result of the SAR (safety and analysis requirements). The SNAP-19 RTG was designed to meet rigorous performance and safety requirements. The design was verified through a combination of testing and analysis. A comprehensive Safety Analysis Report was required to meet requirements for the launch of a nuclear device. This analysis was accomplished with the help of several of the National Laboratories including Los
Alamos, Sandia, Livermore, and Oakridge. The food chain contamination analysis tested for the impact on particles if there was a leak. How much contamination into water systems, agriculture, food, and air. One of the structural tests involved mounting a fuel capsule on a train track and running a locomotive into the capsule at over 60 miles per hour. The result of that test was the minor structural damage but no breach of the capsule.