Class I UAV

The U.S. Department of Defense (DoD) employs Unmanned Aerial Systems (UAS) across all echelons to support tactical, operational, and strategic operations. The types of UAS that are used in these operations are categorized into "Groups" according to their size and capability. Previous to 2010, UAS were categorized into "Tiers" or "Classes" separately by each branch of the military. In order to promote a homogeneous categorization, the "group system" was developed.

The "Group" system has 5 categories, from 1 to 5, with each category increasing in capability.

The previous classification system, termed the "Tier System", was used by military planners to designate the various individual aircraft elements in an overall usage plan for integrated operations. The Tiers do not refer to specific models of aircraft, but rather roles the aircraft would fill. The U.S. Air Force, U.S. Marine Corps, and U.S. Army each have their own tier system, and the systems are themselves not integrated.

Role currently filled by the AAI RQ-7 Shadow, although USMC planners do not view this aircraft as meeting future Tier III requirements.

Future Combat Systems (FCS) was the United States Army's principal modernization program from 2003 to early 2009.

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