According to Russian publications, the Russia-based rocket propulsion company Energomash has signed a deal to sell six more RD-180 rocket engines to United Launch Alliance in 2020. These six engines will allow for six additional flights of the Atlas V rocket, which flies national security payloads and science missions for the US government. Soon, the rocket will also fly Boeing's crewed Starliner spacecraft into orbit.

NASA has understandably made a big deal out of its commercial crew program through which it is paying Boeing and SpaceX to develop spacecraft that will allow astronauts to launch to the International Space Station from Florida. Since the 2011 retirement of the space shuttle, NASA has gotten its people into space aboard Russian rockets launching from Kazakhstan.

Seizing upon this announcement, the Russian embassy in Washington, DC, evidently felt the need to troll United Launch Alliance, the US military, and NASA on Twitter, saying, "Russian rocket engines to continue launching America into space."

Russian rocket engines to continue launching America into space🚀 The cheaper and more reliable RD-180 engine is developed and manufactured by #Energomash and is designed for the US Atlas carrier rockets @ulalaunch 👉 https://t.co/S2lYYm8Pip pic.twitter.com/thuDbi7WSp — Russia in USA 🇷🇺 (@RusEmbUSA) July 31, 2018

Why RD-180s?

The Atlas V rocket has an exceptional track record and has launched many important spy and communications satellites—as well as science missions—for the US government since its debut in 2002. Although it is more expensive than its competitors in the medium-lift category of rockets, the Atlas V can boast of a proven track record with 100-percent mission success.

But there is one flaw with this rocket—its first stage relies on a single Russian-made RD-180 engine to reach orbit. It made sense to choose this engine for the new Atlas launcher in the late 1990s, when US-Russian relations were thawing and American policymakers wanted to keep Russian rocket scientists employed on aerospace projects rather than risking them moving to other countries that might want their skills for the development of intercontinental ballistic missiles. It also helped that the reliable RD-180 engine cost considerably less than US-made counterparts.

However, after Russia's annexation of Crimea in 2014, the RD-180 engine became a liability for the Atlas V rocket and its manufacturer, United Launch Alliance. US Senators demanded that the rocket company stop using the RD-180 engine, and United Launch Alliance moved to develop a new rocket, the Vulcan, with American-made engines. This new rocket could take flight as soon as 2020, but it will probably be delayed into 2021.

Commercial crew

The agreement to buy more RD-180 engines comes as NASA will announce the crews for the first flights of Boeing's Starliner and SpaceX's Dragon spacecraft on Friday morning. These flights should take place some time in 2019.

NASA has been promoting the commercial crew program with the "Launch America" tagline and hashtag. And while it's true that both companies will launch their rockets from US soil, the additional purchases of RD-180 engines suggest that at least a few Starliner crews will still ride into space on top of a Russian engine. In a recent report on the commercial crew program, the US Government Accountability Office cited limited access to data about the Russian engine as one of three top "programmatic risks" for further delays.

By contrast, the other provider of commercial crew services, SpaceX, produces its Falcon 9 rocket almost entirely from US components.