This Aviation Facilities Design Guide (DG 415-3) sets forth general functional guidance for the design architect-engineer (A-E) to use in developing the design and the construction documents for Army National Guard (ARNG) Aviation Support Facilities projects that qualify for support, totally or in part, from Federal funds. The guidance herein is applicable to all construction projects, including new construction as well as alterations to and rehabilitation and conversion of existing facilities. All ARNG facilities must be designed and constructed applying the principles and practices of sustainable design and development using U.S. Green Building Council LEED-NC Version 3.0 Green Building Rating System to achieve a “Silver” rating.