Alliance Ground Surveillance (AGS)

  • Last updated: 04 Sep. 2023 11:09

NATO's Alliance Ground Surveillance (AGS) system is composed of five NATO RQ-4D ''Phoenix'' remotely piloted aircraft and a series of associated ground command and control stations. The AGS system gives commanders a comprehensive picture of the situation on the ground, providing a state-of-the-art Intelligence, Surveillance and Reconnaissance (ISR) capability to NATO.

Naval Air Station Sigonella, Italy - NATO'€™s first RQ-4D has arrived in Europe.


  • The AGS system consists of air, ground and support segments, performing all-weather, persistent wide-area terrestrial and maritime surveillance in near real-time.
  • AGS provides in-theatre situational awareness to commanders of deployed forces.
  • AGS contributes to a range of missions such as protection of ground troops and civilian populations, border control and maritime safety, the fight against terrorism, crisis management and humanitarian assistance in natural disasters.
  • All five NATO AGS aircraft are located at the AGS Main Operating Base in Sigonella, Italy. 



The NATO-owned and -operated AGS core system enables the Alliance to perform persistent surveillance over wide areas from the high-altitude, long-endurance (HALE) aircraft, operating at considerable stand-off distances and in any weather or light condition. Using advanced radar sensors, these systems continuously detect and track moving objects throughout observed areas and provide radar imagery of areas of interest and stationary objects.

The NATO AGS Force is based at the AGS Main Operating Base in Sigonella, Italy. The base hosts around 400 AGS personnel, in addition to a small number of AGS staff elements based at Allied Command Operations in Mons, Belgium and at Allied Air Command in Ramstein, Germany. The AGS Main Operating Base serves as a NATO Joint Intelligence, Surveillance and Reconnaissance (JISR) deployment base and as a data exploitation and training centre.

Just as NATO Airborne Early Warning & Control (NAEW&C) aircraft – also known as AWACS or “NATO’s eyes in the sky” – monitor Alliance airspace, AGS is able to observe what is happening on the Earth’s surface, providing situational awareness before, during and, if needed, after NATO operations.

The AGS system was acquired by 15 NATO Allies: Bulgaria, Czechia, Denmark, Estonia, Germany, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Romania, Slovakia, Slovenia and the United States. Shortly after AGS declared Initial Operational Capability on 15 February 2021, responsibility for the sustainment of the AGS capability transferred to all Allies.

On completion of the acquisition process and handover of the AGS to NATO, responsibility for programme management and through-life support passed to the NATO Support and Procurement Agency (NSPA). The engagement of NATO common funds for infrastructure, communications, operation and support follows normal funding authorisation procedures applicable within the Alliance.


Technical components

The AGS core is an integrated system consisting of the air segment, a ground segment and a support segment.

The air segment consists of the five NATO RQ-4D aircraft. The aircraft are equipped with a multi-platform radar technology insertion programme (MP-RTIP) and synthetic aperture radar (SAR) ground surveillance radar sensors, as well as an extensive suite of line-of-sight and beyond-line-of-sight, long-range, wideband data links.

The ground segment consists of a number of ground stations in fixed, mobile and transportable configurations, able to provide data-link connectivity, data-processing, exploitation capabilities and interfaces for interoperability. The ground segment provides an interface between the AGS core system and a wide range of command, control, intelligence, surveillance and reconnaissance (C2ISR) systems. It interconnects with multiple deployed and non-deployed operational users, as well as with reach-back facilities away from the surveillance area. 

The AGS core support segment includes dedicated mission support facilities at the AGS Main Operating Base in Sigonella. The composition of the AGS core system and national contributions in kind will provide NATO with considerable flexibility in employing its ground surveillance capabilities.

This will be supplemented by additional Allied interoperable airborne surveillance systems, under the Joint ISR concept, tailored to the needs of a specific operation or mission conducted by the Alliance.


Facts and figures about the NATO RQ-4D

General characteristics of the NATO RQ-4D remotely piloted aircraft:

  • Primary function: High-altitude, long-endurance intelligence, surveillance and reconnaissance
  • Power plant: Rolls Royce-North American AE 3007H turbofan
  • Thrust: 7,600 lbf /  33800 N
  • Wingspan: 130.9 ft / 39.8 m
  • Length: 47.6 ft / 14.5 m
  • Height: 15.3 ft / 4.7 m
  • Weight: 14,950 lbs / 6,781 kg
  • Maximum take-off weight: 32,250 lbs / 14,628 kg
  • Fuel capacity: 17,300 lbs / 7,847 kg
  • Payload: 3,000 lbs / 1,360 kg
  • Speed: 310 knots / 357 mph / 575 kph
  • Range: 8,700 nautical miles / 10,112 miles / 16,113 km
  • Ceiling: 60,000 ft / 18,288 m


  • expand timeline

    Originating from NATO’s Defence Planning Committee in 1992, the AGS programme was defined as a capability acquisition effort in 1995, when NATO Defence Ministers agreed that “the Alliance should pursue work on a minimum essential NATO-owned and -operated core capability supplemented by interoperable national assets.

    The AGS programme was to provide NATO with a complete and integrated ground surveillance capability that would offer the Alliance and its member countries unrestricted and unfiltered access to ground surveillance data in near real-time, and in an interoperable manner. It was to include an air segment comprising airborne radar sensors, and a ground segment comprising fixed, transportable and mobile ground stations for data exploitation and dissemination, all seamlessly interconnected through high-performance data links.

    From the outset, the AGS capability was expected to be based on one or more types of ground surveillance assets either already existing or in development in NATO member countries, an approach that later also came to include proposed developmental systems based on American or European radar. However, all those approaches failed to obtain sufficient support by the Allies to allow their realisation. In 2001, the North Atlantic Council decided to revitalise AGS through a developmental programme available to all NATO countries and a corresponding cooperative radar development effort called the Transatlantic Cooperative AGS Radar (TCAR).

    In 2004, NATO decided to move ahead with what was labelled as a mixed-fleet approach. The air segment was to include Airbus A321 manned aircraft and Global Hawk unmanned aerial vehicles (UAVs), both carrying versions of the TCAR radar, while the ground segment was to comprise an extensive set of fixed and deployable ground stations.

    Due to declining European defence budgets, NATO decided in 2007 to discontinue the mixed-fleet approach and instead to move forward with a simplified AGS system where the air segment was based on the off-the-shelf Global Hawk Block 40 UAV and its associated MP-RTIP sensor. The ground segment, which would largely be developed and built by European and Canadian industry, remained virtually unchanged as its functional and operational characteristics were largely independent of the actual aircraft and sensor used.

    In February 2009, the NATO Allies participating in the AGS programme started the process of signing the Programme Memorandum of Understanding (PMOU). This was a significant step forward on the road towards realising an urgently required, operationally essential capability for NATO. The NATO Alliance Ground Surveillance Management Agency (NAGSMA) was established in September 2009, after all participating countries had agreed on the PMOU. The PMOU served as the basis for the procurement of this new NATO capability.

    Another important milestone for the AGS programme was the 2010 Lisbon Summit, where the strong operational need for a NATO-owned and -operated AGS capability was reconfirmed with NATO’s 2010 Strategic Concept. AGS also featured in the Lisbon Package as one of the Alliance’s most pressing capability needs.

    On 3 February 2012, the North Atlantic Council decided on a way ahead to collectively cover the costs for operating AGS for the benefit of the Alliance. The decision to engage NATO common funding for infrastructure, satellite communications and operations and support paved the way for awarding the AGS acquisition contract. In addition, an agreement was reached to make the UK Sentinel system and the future French Heron TP system available as national contributions in kind, partly replacing financial contributions from those two Allies.

    In the margins of the 2012 NATO Summit in Chicago, NATO Allies took an important step towards the delivery of a NATO-owned and -operated ground surveillance and reconnaissance capability. A procurement contract for the AGS system was signed on 20 May 2012, in preparation for the delivery of a vital capability that would be made available to all NATO member countries. NAGSMA, representing the 15 AGS acquiring countries, awarded the prime contract for the system to Northrop Grumman. The company's primary industrial team included Airbus Defence and Space (Germany), Leonardo (Italy) and Kongsberg (Norway), as well as leading defence companies from all acquiring countries, which contributed to the delivery of the AGS system. The AGS acquisition contract included the purchase and initial operation and maintenance of unmanned aircraft equipped with advanced ground surveillance radar sensors.

    Designated the AGS NATO RQ-4D, NATO’s remotely piloted aircraft is based on the US Air Force Block 40 Global Hawk. It has been uniquely adapted to NATO requirements to provide a state-of-the-art Intelligence, Surveillance and Reconnaissance (ISR) capability to NATO.

    In September 2015, NATO AGS achieved important milestones such as the first live ground testing of NATO’s first RQ-4D aircraft and the activation of NATO AGS Force, meaning Allies formally agreed the configuration (number of staff, their rank structure, etc.) of the unit responsible for operating the AGS NATO RQ-4D remotely piloted aircraft from Sigonella Air Base.

    Between September and December 2015, other important milestones were achieved:

    • Mobile General Ground Station (MGGS) and Transportable General Ground Station (TGGS) roll-outs took place;
    • The first test flight of NATO’s first RQ-4D occurred in Palmdale, California; and
    • AGS successfully participated in exercise Trident Juncture 2015 from the NATO AGS Capability Testbed (NACT) in the Netherlands.

    From 2016 to 2019, a number of test flights took place in order to further develop and test AGS capabilities. These included the first flight remotely controlled from the AGS Main Operating Base in Sigonella at the end of 2017.

    Throughout 2018 and 2019, AGS temporary infrastructure at the Main Operating Base was put in place. The construction of permanent facilities for AGS began on the site and is expected to be completed in 2022. 

    Training of AGS pilots, Joint ISR analysts, sensor operators and maintainers is ongoing at the Main Operating Base, marking the first steps for the creation of a Premier NATO Training Centre in Sigonella. The centre will host 22 training instructors including mission crew and pilot trainers, working with a simulation capability that will be able to take on around 80 trainees per year.

    The first of five AGS NATO RQ-4D aircraft landed at its new permanent home in Sigonella, Italy on 21 November 2019. The first AGS ferry flight from the United States to Italy marked the implementation of a key multinational project for the procurement of state-of-the art equipment. Following arrival, a system-level performance verification phase was undertaken in order to ensure full compliance of the system with NATO requirements. The second AGS NATO RQ-4D aircraft landed in Sigonella on 19 December 2019, followed by the remaining three respectively on 15 July 2020, 26 July 2020 and 12 November 2020.

    Handover of the entire AGS system to the NATO AGS Force commenced in November 2020. Initial operational capability was achieved on 15 February 2021. Full handover was completed on 31 March 2022, when AGS was fully transferred from the 15 AGS acquiring countries (organised through NAGSMA) to all NATO Allies and the NSPA.