A J-2 engine undergoes static firing. The J-2, developed under the direction of the Marshall Space Flight Center, was propelled by liquid hydrogen and liquid oxygen. A single J-2 was utilized in the S-IVB stage (the second stage for the Saturn IB and third stage for the Saturn V) and in a cluster of five for the second stage (S-II) of the Saturn V. Initially rated at 200,000 pounds of thrust, the engine was later uprated in the Saturn V program to 230,000 pounds.
NASA
1965
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