United Launch Alliance (ULA), the Denver-based company that builds and operates the Atlas 5 and Delta 4 rockets, joined the Commercial Spaceflight Federation as an executive member, the Washington-based trade association announced June 21.

ULA received a $6.7 million award under NASA’s Commercial Crew Development Program in February to work on an emergency detection system that could be installed on Atlas 5 and Delta 4 rockets launching crew.

ULA, however, did not sign a June 22 open letter to Congress calling on lawmakers to fully fund President Barack Obama’s plan to replace the space shuttle with commercial rockets. Among the more than 50 people who signed the letter were Commercial Spaceflight Federation President Bretton Alexander and the top executives of many of the federation’s member companies.

ULA spokesman Mike Rein told Space News July 25 that the company remains support of NASA’s new strategic initiative.

“All interested parties are well aware of ULA’s position and capabilities when it comes to the new commercial space initiative,” Rein said in an e-mail. “We stand ready to support any policy that is decided upon by the leadership of our nation.”