WASHINGTON — The U.S. Air Force formally requested bids July 15 for the first competitively awarded contract under its main satellite launching program since 2006, a step that coincided with the latest congressional push to expand the number of Pentagon missions being put up for grabs.

The first of the competitively awarded Evolved Expendable Launch Vehicle missions would be conducted on behalf of the U.S. National Reconnaissance Office, which operates the nation’s spy satellites, according to a notice posted on the Federal Business Opportunities procurement website. Proposals are due Aug. 14 for the mission, dubbed NROL-79, the notice said. The launch could take place at Cape Canaveral Air Station in Florida or at Vandenberg Air Force Base in California.

Gen. William Shelton, commander of Air Force Space Command, told SpaceNews July 16 that the service and Space Exploration Technologies Corp., which is challenging incumbent provider United Launch Alliance for a piece of the Pentagon market, were working hard to certify the company’s Falcon 9 rocket in time to compete for the mission.

The bid solicitation came on the same day that the Senate Appropriations defense subcommittee marked up a defense spending bill that recommends giving the Air Force $125 million next year to increase the number of competitive launch opportunities under the EELV program. Currently the Air Force is planning to put seven, and possibly eight, EELV missions up for bid over the next two years.

“Competition is a good thing and there is no competition in this to speak of,” Sen. Richard Durbin (D-Ill.), the subcommittee’s chairman, said of the national security launch marketplace during the July 15 markup hearing. “We’re going to change that with this bill.”

Currently, virtually all operational U.S. national security missions are launched by Denver-based ULA, established in 2006 by the once-competing launch business of Boeing and Lockheed Martin.

As part of its plan to reduce its satellite launching costs while mollifying critics of ULA’s monopoly, the Air Force has ordered a large batch of rockets on a sole-source basis from the incumbent — SpaceX is challenging that deal in federal court — while setting aside an additional seven to eight missions for competition. Previously, the service planned to competitively award as many as 14 missions.

The reduction, which the Air Force said was driven by changing mission requirements, has drawn criticism from SpaceX and its supporters.

The report accompanying the draft bill from the subcommittee said the $125 million would go toward the Air Force accelerating its work to put an eighth launch up for competitive bid.

The House Armed Services Committee has proposed something similar in its version of the 2015 defense authorization bill, directing the Air Force to use money it requested for a new weather satellite development program and apply it to the launch of an aging meteorological craft in what would be the eighth competitively awarded EELV launch.

“The folks at SpaceX said ‘we’re ready to compete,’” Durbin said. “Let’s give them the chance. Let’s do it this next year. I think it’s going to be interesting. I think it’s going to reduce costs.”

Since assuming the chairmanship of the Senate Appropriations defense subcommittee in January 2013, Durbin has taken a keen interest in the Pentagon’s satellite launching program. In March, he called a hearing that brought together SpaceX Founder and Chief Executive Elon Musk and ULA President and Chief Executive Michael Gass.

The Senate bill also includes $25 million for work on a new rocket engine, according to a July 15 press release from the committee. One of ULA’s two main rockets, the Atlas 5, is powered by a Russian-built engine whose availability has come into question following Russia’s incursion into neighboring Ukraine.

“America’s access to space should not depend on a state-owned foreign [company], which has dreams of empire at the cost of its innocent neighbors,” Durbin said.