Unmanned Aerial Vehicles (UAVs) have been referred to in many ways: RPVs (remotelypiloted vehicle), drones, robot planes, and pilotless aircraft are a few of the terms that have beenused. Most often called UAVs, they are defined by the Department of Defense (DOD) as powered,aerial vehicles that do not carry a human operator, use aerodynamic forces to provide vehicle lift,can fly autonomously or be piloted remotely, can be expendable or recoverable, and can carry a lethalor nonlethal payload. Ballistic or semiballistic vehicles, cruise missiles, and artillery projectiles arenot considered UAVs by the DOD definition. (1) Drones differ from RPVs in that they are designed to flyautonomously. UAVs are either described as a single air vehicle (with associated surveillancesensors), or a UAV system (UAS), which usually consists of three to six air vehicles, a groundcontrol station, and support equipment. The military use of UAVs in recent conflicts such as Iraq (2003), Afghanistan (2001), andKosovo (1999) has opened the eyes of many to the advantages and disadvantages provided byunmanned aircraft. UAVs regularly make national headlines as they are used to perform taskshistorically performed by manned aircraft. UAVs are thought to offer two main advantages overmanned aircraft: they eliminate the risk to a pilot's life, and their aeronautical capabilities, such asendurance, are not bound by human limitations. UAVs may also be cheaper to procure and operatethan manned aircraft. UAVs protect the lives of pilots by performing the "3-D" missions - those dull,dirty, or dangerous missions that do not require a pilot in the cockpit. However, the lowerprocurement cost of UAVs must be weighed against their greater proclivity to crash, while theminimized risk should be weighed against the dangers inherent in having an unmanned vehicle flyingin airspace shared with manned assets. There are a number of reasons why the employment of UAVs has recently grown. Navigation and communication technology is now available that wasn't available just a few shortyears ago. Some say that the services' so-called "silk scarf syndrome" of preferring manned aviationover unmanned, has diminished as UAVs entered the mainstream. Although only recently procured in significant numbers by the United States, UAVs have hada century-old history in aviation. First included in Jane's All the World's Aircraft in 1920, UAVswere tested during World War I, but not used in combat by the United States during that war. However, it was not until the Vietnam War that UAVs such as the AQM-34 Firebee were used ina surveillance role. The Firebee exemplifies the versatility of UAVs -- initially flown in the 1970s,it was modified to deliver payloads and flew its first flight test as an armed UAV on December 20,2002. (2) The Israeli Air Force pioneered several UAVs in the late 1970s and 1980s that wereeventually integrated into the United States's UAV inventory. U.S. observers noticed Israel'ssuccessful use of UAVs during operations in Lebanon in 1982, encouraging then-Navy SecretaryJohn Lehman to acquire a UAV capability for the Navy. Interest also grew in other parts of thePentagon, and the Reagan Administration's FY1987 budget requested notably higher levels of UAVfunding. (3) This markedthe transition of UAVs in the United States from experimental projects to acquisition programs. One of the UAVs acquired from Israel, Pioneer, emerged as a useful source of intelligenceat the tactical level during Operation Desert Storm. Pioneer was used by Navy battleships to locateIraqi targets for its 16-inch guns. Following the Gulf War, military officials recognized the potentialvalue of UAVs, and the Air Force's Predator became a UAV on a fast track, quickly adding newcapabilities. (4) Debutingin the Balkans conflict, the Predator performed surveillance missions such as monitoring area roadsfor weapons movements and conducting battle damage assessment. Operations in Afghanistan havefeatured the Air Force's Global Hawk, as well as adding a new mission for Predator that allows theUAV to live up to its name -- armed reconnaissance. There are currently five major UAVs in theU.S. inventory: the Navy and Marine Corps's Pioneer, the Air Force's Global Hawk and Predator,and the Army's Hunter and Shadow UAVs. Reflecting a growing awareness and support in Congress for UAVs, investment in unmannedaerial vehicles has increased annually. The FY2001 investment in UAVs was approximately $667million, while the FY2003 funding totaled over $1.1 billion dollars. The Pentagon has asked for$1.6 billion in procurement and development funding for FY2006, with much more planned for theout years. Congress's role in UAV development has been one of strong encouragement tempered withconcern. Taking a proactive stance in UAV program management, Congress has in the past directedthe formation of joint program offices to ensure commonality between the services' UAV programs. Congress has also expressed concern that DOD's "growing enthusiasm may well lead to a situationin which there is no clear path toward the future of UAVs", and so has required DOD to submit aUAV roadmap. (5) In someinstances, Congress has advocated a more aggressive approach to fielding UAVs. For example, in1996, the House Armed Services Committee (HASC) supported legislation directing DOD toweaponize both the Predator and Hunter, but DOD opposed the initiative. (6) The scope of Congress'ssupport and confidence in UAV technology can be gleaned from a prediction in the reportaccompanying the National Defense Authorization Act for Fiscal Year 2001, which stated that,"Within ten years, one-third of U.S. military operational deep strike aircraft will be unmanned." (7) In recent years, the pace of UAV development has accelerated, and the scope of UAVmissions and applications has expanded. How should these efforts be managed so that they arecost-efficient, effective, and interoperable? In its eagerness to deploy UAVs, does DoD riskduplication of effort between various programs? Are DOD UAV acquisition plans responsive tocongressional direction? Investment priorities could change as the introduction of UAVs into the U.S. inventory shiftsthe balance between manned and unmanned capabilities. Congress, as part of its defense oversightresponsibilities, may assess DOD's current UAV efforts to verify that they match up with newinvestment goals and strategies. Conventional wisdom states that UAVs are cheap, or cost-effective. Is this true today? How do UAV costs compare to manned aircraft costs? UAVs have traditionally been used for reconnaissance and surveillance, but today they arebeing employed in roles and applications that their designers never envisioned. The unanticipatedflexibility and capability of UAVs has led some analysts to suggest that more, if not most, of themissions currently undertaken by manned aircraft could be turned over to unmanned aerial platforms,and that manned and unmanned aircraft could operate together. Congress may have to contemplatethe replacement of a significant portion of the manned aircraft fleet with unmanned aircraft that haveyet to be designed. The defining characteristic of UAVs is that they are "unmanned." If UAVs are introducedinto the force in large numbers, might personnel issues arise? Recruitment and retention is aperennial congressional issue, that may be receiving increased attention due to the operationalstresses associated with the Global War on Terrorism. What impact might wide spread deploymentof UAVs have on military personnel? Industrial base issues also need to be considered. If defense companies devote more of theirtime and expenses to develop unmanned aircraft, will the skills and technologies needed for mannedaircraft design erode? Those who argue that UAVs will replace manned aircraft in the future are notas concerned with the industrial base issue as those who feel manned aircraft will still be needed tocombat future threats. As U.S. companies compete for business in a growing international UAV marketplace,concerns about the proliferation of these systems may grow. Are steps required -- and if so, whatmight they be -- to control the spread of UAVs? As part of its defense and foreign policy oversight,Congress may examine whether a balance must be struck between supporting legitimate U.S. exportsand curbing the spread of UAV technologies to dangerous groups or countries. Undeniably, UAVs are being developed, procured and fielded in growing numbers. Thediversity of designs and applications is also accelerating. Considering this growth, many in Congressmay wish to evaluate the management of UAVs: Are UAVs being developed fast enough? Are theybeing developed too fast? Has DoD developed an appropriate plan and structure for incorporatingUAVs into future military capabilities? UAV programs range from the combat tested -- Pioneer, Hunter, Predator and Global Hawk-- to the not yet tested -- the Air Force and Navy's Unmanned Combat Air Vehicles. Sizes andranges of UAVs also vary greatly: the Wasp Micro UAV at 8 inches long has a combat radius of 5nautical miles, while the Global Hawk at 44 feet long (the size of a medium sized corporate jet) hasa combat radius of 5,400 nm.