General aviation industry representatives accept the inevitability of unmanned aircraft systems (UAS) flying in civil airspace, though they urge a go-safely approach to introducing robotic aircraft. “[AOPA is]  certainly an advocate of new aircraft entering the airspace system. It’s a matter of doing that safely. The introduction of UAS is inevitable, it’s here,” Heidi Williams, AOPA’s senior director of airspace and modernization, told attendees last week at the Unmanned Systems North America conference in Washington, D.C. Currently, unmanned aircraft in the U.S. can operate only in restricted airspace or through certificates of authorization (CoA) issued by the FAA to public agencies. A company that seeks to operate a UAS must obtain a special airworthiness certificate-experimental category (SAC-EC). There are 285 active CoAs and 15 active SAC-ECs, according to the FAA. A proposed rulemaking governing the operation of small UAS–nominally 50 pounds or lighter–is also anticipated by December, with a final rule expected in mid-2013. In June, the FAA established an aviation rulemaking committee to consider allowing larger unmanned aircraft to fly in civil airspace.