Military Personnel: Actions Needed to Better Position the Navy and the Marine Corps to Support Expanding Unmanned Systems Operations, Report to Congressional Committees [open pdf - 5MB]
"The Navy and the Marine Corps are rapidly growing their portfolios of unmanned aerial systems (UAS) and unmanned maritime systems and have opted to use military personnel as operators without evaluating alternatives, such as federal civilian employees and private sector contractors. Service officials stated that civilians or contractors are not viable alternatives and policies are unclear about when and how to use them. However, a June 2016 Department of Defensecommissioned study found that alternative staffing strategies could meet the UAS mission more cost-effectively. Military personnel may be the most appropriate option for unmanned systems, but without clarifying policies to identify circumstances in which civilians and contractors may serve in operational roles, the services could continue to make workforce decisions that do not consider all available resources."
Government Accountability Office: http://www.gao.gov/