On July 30, United Launch Alliance (ULA) launched the last of the top-secret satellites for the benefit of the US military into orbit using the Atlas V rocket. This ended the Pentagon’s use of Russian RD-180 engines in connection with the transition to entirely American boosters and engines.

The Atlas V launched from Cape Canaveral Space Station in Florida on July 30. The carrier was equipped with a Russian-made RD-180 engine and five solid-fuel boosters mounted in the most powerful configuration.

This was the 101st launch of the Atlas V missile since its debut in 2002, and the last of 58 total missiles to carry payloads for the U.S. military. U.S. Space Command confirmed the successful deployment of the payload.

At the same time, the July 30 launch marked the end of an era that began in the 1990s, when Washington policy allowed Lockheed Martin, the original developer of the Atlas V, to use Russian rocket engines in the first stage. At the time, the Pentagon was procuring new missiles to replace older versions of the Atlas, Delta and Titan families of launch vehicles that had been in service since the late 1950s or early 1960s.