Air Force Secretary Deborah Lee James testified before the Senate Armed Services Committee, along with Under Secretary of Defense for Acquisition, Technology and Logistics Frank Kendall, on military space launch and the use of Russian-made rocket engines Jan. 27.

During her testimony, James highlighted space capabilities' role in national security, the importance of modernization and the need for end-to-end space launch services.

"The U.S. relies upon space as an essential element of our national security," James said in her opening statement. "Space provides us with the ability to operate effectively around the world, to understand what our own forces are doing and to stay ahead of our adversaries. Space is key to projecting credible and effective power around the world to support our allies and deter aggression."

Maintaining the advantage requires the ability to modernize and replenish space architecture through a reliable launch capability, which remains the Air Force's number one space priority, James continued.

Assured access to space requires end-to-end space launch services and not just a rocket engine, James said in her written testimony.

"The Department would strongly prefer not to fund a rocket engine alone because a rocket alone will not get us to space," James said. "We need an entire capability, not just one single component. We need to expand on our horizon and keep focusing on the launch capability in its totality of which the engine is a key component, but it's not the only component."

The Air Force has been operating in space for decades and remains dedicated to maintaining its advantage. Exploring types of rocket propulsion systems in a competitive way could lead to having new competitors and new capabilities for space access.

"There are fantastic developments in the commercial world," James said. "We are following them, we are celebrating them, and we are putting some of our resources, time and energy toward trying to get them there because we will all benefit from it."