## 1 Introduction  
In July 2014, the Teal group predicted that worldwide Unmanned Aerial Systems (UASs) expenditures will grow to over $11 Billion per year with a total investment of over $91 Billion by 2024. It is expected that 86% of the market will be military and 14% will be in the civil market [1,2]. As the growth continues, challenges and expectations will continue to rise as users will expect more robust and capable vehicles. The military market continues to expand and develop new capabilities and requirements. The growth in the civil market is expected to significantly expand as the rules on civil use of UASs in the US and around the world become better defined. As these markets expand, the need to have systems that can adapt to new missions, sensors, and environments will drive requirements. The Defense Advanced Research Projects Agency (DARPA) released a Broad Agency Announcement (BAA) for the Collaborative Operations in a Denied Environment (CODE) Program in 2014 [3]. This BAA defines numerous requirements and expectations for future system capability of unmanned and autonomous vehicles working as single systems and multiple vehicle teams. Many of the requirements defined in the CODE BAA can be utilized to define system architecture and capabilities for both military and civilian systems. These requirements will provide a significant portion of the requirements for the system defined herein. In early 2014, DARPA also released a BAA for Distributed Battlespace Management (DBM) that proposes a series of automated and autonomous decision aids to assist battle managers and pilots [4]. The DBM envisions, amongst other needs, the ability to enable improved command and control of autonomous operations of UASs, including in manned-unmanned teams. There are multiple thrusts within the DBM program, but one of the primary ones is for improved distributed adaptive planning and control. Additionally, requirements that can be applied globally across UASs from the Federal Aviation Administration (FAA) and other federal, state, and local laws are considered. There are a significant number of current and future uses for UASs throughout the military and civilian world. The military is currently using, and continues to anticipate increased usage of, these systems in numerous areas including intelligence, surveillance, and reconnaissance (ISR) [5; 6], data and communication interfaces [7], electronic warfare [8; 9], and limited attack roles [10]. Future cargo and transport capabilities [11] along with search and rescue operations [12] have been envisioned. In the commercial world, there are almost limitless possibilities of uses. Currently, applications exist for agriculture, firefighting, police, sciences, and forestry [2]. Significant efforts in cargo delivery, data capabilities, search and rescue, and traffic information are underway. Evaluating all of these capabilities and needs result in four primary mission types: ISR, persistent loiter, delivery, and attack. These four mission types will define the needs and requirements of the majority of the future UASs across the industry. An early systems engineering analysis to evaluating the requirements, needs, and capabilities must be performed in an attempt to define a system that can be robust and adaptive to current and future needs. Utilizing requirements defined in the CODE BAA and other resources, a set of requirements can be defined and utilized to develop a system architecture to meet the users' needs. Section 2 provides a high-level problem definition that is addressed by this system architecture design. Section 3 will provide this systems engineering review and architecture definition. Future multiple-scenario capability will require the system to operate dynamically across one or more of the four mission types and numerous subsets of those missions. Multiple-scenario control algorithms and architectures will enable a single platform to perform multiple mission roles with minimal reconfiguration.