This paper presents trade-offs for purchase of legacy military rotorcraft by expanding on considerations relevant to airworthiness certification with focus on a recommended approach to achieving the aircraft airworthiness type design certificate. The airworthiness certification approach utilizes basic principles of systems engineering, such as early planning and rigorous requirements development, and is structured in seven ordered elements: 1) Statement of Operating Intent (SOI), 2) Airworthiness Authority, 3) Key Agreements, 4) Airworthiness Criteria, 5) Contract Award, 6) Compliance Data, and 7) Aircraft Type Design Certificate. The approach enables risk identification and opportunities in support of decision making necessary to effectively choose a successful and cost-effective option.