Safety Design for Space Operations

Stainless Steel Tank

Metallurgical analyses were performed on the Delta II Stage 2 stainless steel propellant tank. Photographs (Figure 9.4.2) show that that the Stage 2 tank was largely intact upon landing on Earth. The Stage 2 tank had a long circumferential crack and a flattened top resulting from impact damage (see Figure 9.4.4).

FIGURE 9.4.4 Photograph of re-entered Delta II Stage 2 tank showing apparent molten hole. (photo courtesy NASA)

The melting point for the tank (410 stainless steel) is approximately 1500°C. The forward dome of the tank had a large hole with a jagged periphery of re-solidified molten metal (Figure 9.4.4), which ...