2.1 MISSION Endurance UAV systems provide a broad spectrum of intelligence collection capability to support joint combatant forces in worldwide peace, crisis, and wartime operations. The capabilities of these UAV systems will provide for adaptive real-time planning of current operations, to include: monitoring enemy offensive and defensive positions, deception postures and combat assessment. Endurance UAVs will provide a rapid turnaround of raw data to aid a robust targeting cycle following a "First Look, First Shoot, First Kill" methodology.

 2.2 TASK The ability of endurance UAVs to provide 24-hour coverage in an area of interest with high quality sensors will give the theater CINC additional advantages and capabilities, while providing a force multiplier, and complement manned/space reconnaissance. Covering the spectrum from peace to war, potential applications of endurance UAVs include:

2.2.1 Near- Real -Time (NRT) Targeting and Precision Strike Support Endurance UAV systems will offer opportunities to fulfill time-sensitive targeting requirements by providing a means to shorten the targeting cycle for interdiction campaigns through NRT precise location of mobile enemy forces. The ability to locate, identify, and quickly destroy mobile targets will eliminate the enemy's ability to resupply and maneuver forces. Endurance UAV sensor resolution and accuracy will enable expanded use of precision-guided munitions, improving battlefield efficiency.

2.2.2 NRT Combat Assessment Provides NRT combat assessment of on going operations to the battlefield commander. Immediate feedback of planned and executed operations will assist with the efficient prosecution of campaigns and minimize the fog and friction of war.

  2.2.3 Enemy Order of Battle (EOB) Information Allows a rapid means to develop and track enemy order of battle information, especially in areas where information is sparse.

  2.2.4 Battle Damage Assessment (BDA) Provides high resolution, NRT assessment of target damage. Immediate feedback will support the warfighter’s immediate restrike requirements.

  2.2.5 Intelligence Preparation of the Battlefield (IPB) Survey areas of interest in preparation for battle or amphibious assaults and landings. Significantly enhances Indications and Warning (I&W) capability.

  2.2.6 Special Operations Missions in support of special operations can provide real-time data for mission planning. UAV assets can be used to track high-interest, sea-going vessels, high-interest individuals or organizations. UAV information also has the potential of providing direct imagery down links to ground special operations units that need to "look beyond the horizon" for ingress, targeting, or egress from hostile areas.

2.2.7 Blockade and Quarantine Enforcement Economic, military and drug enforcement blockade and quarantine missions may be supported by UAVs to free up enforcement patrol assets for other missions.

2.2.8 Sensitive Reconnaissance Operations (SRO) SRO missions which, by virtue of collections objectives, means of collection, or area of operations, involve significant military risk or political sensitivity.

2.2.9 Humanitarian Aid Missions in support of humanitarian aid planning can be done virtually anywhere at anytime. The UAV can provide information on the number of people displaced or survey weather damage, etc.

2.2.10 United Nations (UN) Treaty Monitoring A variety of UN missions can be accomplished with endurance UAVs to ensure compliance with UN resolutions. It can alert UN authorities of violations while providing safe and NRT surveillance of areas of interest.

2.2.11 Counter Drugs Missions in support of counter drugs can be accomplished in a variety of environments by endurance UAVs. Endurance UAVs can aid in identification, tracking, and imaging of drug trafficking activities.

2.2.12 Single Integrated Operational Plan (SIOP) Endurance UAVs have the potential to assist missions in support of planning and employment of strategic forces, countering weapons of mass destruction, and nuclear strike assessment.

2.2.13 Communications The high altitude and long endurance of the UAV make it an excellent platform for C4I relay and broadcast systems. UAVs have potential to significantly enhance dissemination of battlefield intelligence and C2 information to all areas and levels of command.

2.3 ENDURANCE UAVs The endurance UAV systems are composed of air vehicles, sensor payloads, datalinks, a launch and recovery element (LRE), portable launch and recovery element (PLRE) (LRE/PLRE are not applicable for Predator UAV), mission control element (MCE) or Ground Control Station (GCS), support element (SE), and trained personnel. The following sections provide information on the operational capabilities and limitations for each of the three tiers in the endurance UAV class to assist in development of system employment concepts.


2.4.1 General The MAE UAV (Tier II) system, named Predator, is designed to provide near-continuous, 24-hour coverage (gaps in orbit coverage are due to the current baseline system limitation of the GCS only having the ability to control one vehicle at a time) at long ranges (500 NM) from the designated launch area. The system is composed of air vehicles (nicknamed the "Predator"), ground control station, sensor payloads, data links, ground support equipment, and trained personnel. (Table 2-4, page 2-18 provides system specifics and a comparison of endurance UAV capabilities.) General Atomics - Aeronautical Systems, Incorporated. is the prime contractor for the Predator UAV program. Some of the other contractors providing key technology include: Lockheed Martin (LORAL) UNISYS for the Ku-Band data link, Westinghouse for the SAR payload, Versatron for the EO/IR payload, and Boeing for data exploitation and mission planning systems.

2.4.2 Predator MAE UAV Ground Control Station (GCS) The Predator MAE UAV GCS is a 30x8x8 foot, triple-axle, commercially available trailer. This trailer is not configured for air mobility and requires special handling to load and unload from C-130 and C-141 aircraft. The trailer incorporates an integral uninterrupted power supply (UPS), environmental control system (cooling only), pilot and payload operator (PPO) workstations, data exploitation,- mission planning,- communication (DEMPC) terminals, and synthetic aperture radar (SAR) workstations. All mission imagery recording is located in the GCS since the Predator has no onboard recording capability. Power is supplied either by commercially supplied power or by dual external 35 kw generators. The entire GCS is transportable by a C-130. The PPO workstations are the primary means for providing direct and responsive provide primary control of the air vehicle and the sensor payload. The DEMPC workstations allow data exploitation, mission planning, mission and payload monitoring, and system management. SAR workstations will control, monitor, and are used for limited exploitation of the SAR data. External communications are via HF/UHF/VHF (voice/data), cellular/landline telephones, and hardwire connectivity with the TROJAN SPIRIT II satellite communication terminal. Other SATCOM systems may be used to link the GCS to an intelligence architecture. Future plans for the GCS include a migration to Houston Fearless type shelters (similar to those currently used with the Contingency Airborne Reconnaissance System [CARS]), enhancing security, supportability, mobility, and commonality with current and future ground systems. The GCS/Predator Control. One GCS controls one Predator, with no ability to relieve a vehicle on station. Original plans were for the GCS to control two Predators, one line-of-sight, and one on the Ku Band link. Technical feasibility and testing of this concept is not included in near term plans.

2.4.3 Mission Planning Station The DEMPC hosts the Mission Planning Station that consists of a Sun SPARC 10 workstation, 17-inch display monitor, keyboard with trackball, and communications panel, along with supporting printers, scanners and storage devices. Primary map-based mission planning and digital map manipulation takes place at this workstation. The Air Force desired migratory mission planning system for Endurance UAV systems is the Air Force Mission Support System. 

2.4.4 Data Exploitation Station Although "first phase exploitation" is not accomplished in the GCS, a limited capability exists. The Data Exploitation station of the DEMPC consists of a Sun SPARC 10 workstation, 17-inch display monitor, keyboard with trackball, and communications panel, along with supporting printers, scanners, and storage devices. Primary data exploitation is performed by imagery exploitation specialists. Each Predator system requires 18 imagery specialists for 24-hour operations, placing high demands for this career field. Image data (to include annotated freeze frames, and voice-overs) are forwarded to the TROJAN SPIRIT II for dissemination by the Joint Deployable Intelligence Support System (JDISS). Electro Optical/Infra Red full motion video is transmittable over the analogue LOS and digital Ku Band links. SAR is transmittable over the Ku Band link only. Full motion video can be disseminated directly by the omni-directional broad beam LOS link (C-Band), via Ku Band TROJAN SPIRIT II (TS II) into the TS II net, or via Very Small Aperture Terminal (VSAT) into the Joint Broadcast System (JBS)/Global Broadcast System (GBS). SAR is a series of still images (no motion). SAR can be disseminated via the TROJAN SPIRIT II Ku Band link to a theater collection cell, intelligence server (JIC/JAC), or to a suitably equipped customer. Motion video will be disseminated directly by the TROJAN SPIRIT II.

2.4.5 Air Vehicle Operator Station The Air Vehicle Operator (AVO) portion of the PPO workstation consists of two 17-inch primary video display monitors; two 9-inch secondary display monitors for air vehicle (AV) status and performance data; desktop controls with throttle, flap, landing gear, keyboard with trackball and joystick controls; and floor-mounted AV brake/rudder control pedals. Displayed information can be modified by menu driven items to optimize the operator configuration. Primary visual information used for manual vehicle control, including takeoff and landings, is provided by a nose-mounted video camera and displayed on one of the primary 17-inch monitors. This station is not entirely interchangeable with the Payload Operator workstation. 

2.4.6 Payload Operator Station The Payload Operator portion of the PPO workstation consists of two 17-inch primary video display monitors; two 9-inch secondary display monitors; desktop controls with throttle, flap, landing gear, keyboard with trackball controls; and floor mounted AV brake/rudder control pedals. Limited data exploitation, to include a frame grab function, is performed by imagery exploitation specialists. Either manual or automatic EO/IR functions and camera settings are controlled at this station. PPO functions can also be performed at the AVO workstation.

2.4.7 Communications Control A broad range of communications equipment is available at each workstation. This includes serial data communications with the AV via the C-band data link for operations within 120 NMLOS and the over-the-horizon (OTH) UHF and Ku-band SATCOM data links. Both data links provide command and control uplinks, and imagery and telemetry downlinks. The UHF link data rate is not suitable for SAR imagery. Initially the MAE UAV system will utilize a narrow band UHF data link. Wide band Ku-band will be available with fielding of the SAR payload. External communications are via redundant HF/UHF/VHF radios, cellular/landline telephones, and hardwire connectivity into the TROJAN SPIRIT II. The GCS has no ability to communicate to an air control facility via the air vehicle. Land lines are currently used. The UHF SATCOM is seldom used due to its low data transfer rate and should be considered to be an emergency back-up vehicle C2 capability. Future plans for modifications include replacing the UHF SATCOM with a full duplex air-to-air/air-to-ground UHF/VHF radio system which will allow connectivity throughout the LOS or Ku Band SATCOM links.

  2.4.8 Air Vehicle The air vehicle is a low-wing monoplane with inverted V-tails and is constructed of composite materials (see Figure 2-1). The air vehicle is intended to be operated from a prepared strip (including grass and dirt runways) similar to light civil aircraft. The AV is constructed of advanced carbon-epoxy and Kevlar composite materials weighing less than 400 pounds. The removable wing structure is designed for a 6G maximum load. The fuselage section contains all fuel, avionics, payloads, parachute, and the power unit. The inverted V-tail is fully articulated and provides stability, rudder control, and protection for the 60-inch ground composite, pusher design propeller. Onboard fuel provides for endurance of approximately 20 greater than 24 hours for an EO/IR/SAR configured aircraft on station at 500 NM from the launch site. Every 20 lbs. of payload added above the basic EO/IR configuration reduces endurance by 1 hour. The parachute can be removed and 90 lbs. of fuel can be added in its place. Payloads will include an EO/IR camera system, and a synthetic aperture radar (SAR) with a SAR available in late 1995. The onboard data links includes both a C-band LOS, and a UHF, and Ku-band (Ku late 1995) OTH satellite data links. A Mode 3 transponder is integrated into the onboard avionics package. The landing gear includes a steerable nosewheel and individually controlled main wheel brakes. An integral emergency recovery system (parachute) is mounted within the fuselage. General aircraft characteristics are listed below in Table 2-1.




Design Loiter Time

Typical Loiter Time


24+ Hours at Operational Radius (EO/IR only)

8-1024+ Hours (EO/IR/SAR with Ku Band SATCOM and parachute)at Operational Radius

Design Operational Radius

Typical Operational Radius

500 NM

200-300 NM

Design Endurance (EO/IR/UHF SATCOM)

Typical Endurance (EO/IR/SAR/Ku Band)

40+ Hours Flight Time at 15,000 ft MSL

16-20 hours sortie at 13,000 ft MSL

Table 2-1: Predator Operational Planning Factors MAE UAV Proposed Flight Characteristics

2.4.9 Air Vehicle Signature The air vehicle was not specifically designed to meet low signature requirements, but due to its small size, composite materials, and shape, although not tested, has it does have inherently low signature characteristics.

2.4.10 Weather Effects The air vehicle is operable in mildly adverse weather, equivalent to instrumented flight by a light civil aircraft. Adverse weather conditions, such as icing, moderate to heavy precipitation airborne or on the ground, or high surface winds may prevent or affect launches or operations. Neither the GCS or the AV are water-proof. Max crosswind limit is 14kts. takeoffs and landings. Maximum ground operation wind limit is 30 kts. The AV has no tie down points and must be hungered during high wind conditions. Maximum true airspeed of the vehicle will be exceeded by winds aloft in excess of 110 kts. Furthermore, areas of responsibility (AORs) with heavy precipitation seasons and adverse landing conditions may severely impede Predator operations. The air vehicle is operable in mildly adverse weather, equivalent to instrumented flight by a light civil aircraft. Adverse weather conditions, such as icing, heavy precipitation, or high surface winds may prevent or affect launches or operations. Furthermore, areas of responsibility (AORs) with heavy precipitation seasons and adverse landing conditions may make MAE UAV operations difficult.

2.4.11 Propulsion The AV is powered by a non-turbocharged Rotax 912 fuel injected motor. The four-cylinder, four-stroke motor produces 85 horsepower at sea level. A gear reduction unit reduces engine RPM at a 2.27:1 ratio, providing for a maximum drive shaft RPM of 2555. This powers a 60-inch, adjustable variable-pitch (an adjustment made on the ground by maintenance personnel), pusher-type propeller and the AV alternator. The compact 912 power plant, including propeller, muffler, and alternator weighs 180 pounds. A turbo-charged ROTAX motor capable of producing 150 hp is being tested. The AV is expected to eventually have a small turboprop power plant.

  2.4.12 Avionics The avionics package includes an integrated Inertial Navigation System (INS)/P-Coded Global Positioning System (GPS), auto pilot controller, IFF transponder, and control avionics for flight systems management.

  2.4.13 Sensor Payloads The baseline payload, Skyball Model 18, incorporates an EO/IR sensor package manufactured by Versatron. Skyball Model 18 is an EO/IR sensor, gyro-stabilized platform with a 360 degree field of view. The payload is slewable in elevation and azimuth. The daylight video camera system includes both spotter and zoom lens. The infrared lens system is a modified Mitsubishi IR-5120 CIV, and has six fields of view available. A Westinghouse developed synthetic aperture radar (SAR) payload provides day and night all-weather still imagery. In Jan 96, a Westinghouse developed SAR payload will be available. Electro-Optical (EO)/Infrared (IR) Commercial off-the-shelf (COTS) EO and IR systems were available when Predator was rolled out in August 1994. The EO and IR payload consists of two daylight video cameras and an IR camera mounted on a stabilized gimbal. The payload provides national imagery interpretation reconnaissance scale (NIIRS) 6 quality imagery (15,000 ft AGL, nadir). The gimbal provides 360 degrees of lower hemisphere coverage for the EO/IR cameras. Synthetic Aperture Radar (SAR) The SAR subsystem will produces a series of spot (approx. 800m x 800m box at 15,000 AGL) continuous, near -real-time, high resolution strip imagery. The subsystem will function autonomously by executing a series of preplanned mission commands loaded prior to operations, which are and will be capable of being altering mission profiles while inflight. Compressed and continuous SAR imagery is not available in the LOS/UHF modes of operation. It can only be transmitted over the 1.5 Mb/s Ku wideband data link via satellite relay to the ground control station (GCS) for decompression and display (with an estimated .5 NIIRS loss).

  2.4.14 Data Link Initial fielding provided will provide for communications with the AV via a C-band data link for operations within LOS and a UHF SATCOM data link for OTH operations. All onboard data link equipment is located in the forward airframe compartment. The latest final configuration will uses the same C-band data link for LOS operations, and a wideband Ku-band and/or UHF SATCOM data link for OTH operations. The UHF SATCOM is seldom used due to its low data transfer rate. Data transfer rates over Ku Band require payload operators to modify their manual payload control technique to compensate for the lower transfer rate. All data links provide command and control uplinks as well as imagery and telemetry downlinks.

2.4.15 Communications The GCS will employ tactical radios for Joint Forces Commander (JFC)/Joint Force Air Component Commander (JFACC) tasking and support from the Component Commander responsible for administrative support to the PREDATOR detachment. The GCS is linked to a TROJAN SPIRIT II trailer, capable of SATCOM relay, and linked to Joint Deployable Intelligence Support System (JDISS) via Joint Worldwide Intelligence Communications System (JWICS) connectivity in the TROJAN SPIRIT network. The GCS will have HF, UHF, VHF, and SHF available communications paths for command and control of the platforms and information relay. Landline secure telephones are also available.

2.4.16 TROJAN SPIRIT II The TROJAN SPIRIT II (TS II) is an Army satellite communications terminal and system which provides access to intelligence dissemination and processing systems. It provides both SCI and collateral circuits over C or Ku Bands. Equipment consists of two high-mobility multi-purpose wheeled vehicles (HMMWV) with shelters, two trailer-mounted SATCOM antennas, and two diesel-powered generators. Two types of ground data terminals are used, a 5.5 meter dish and a 2.4 meter dish. The larger dish is used for imagery relay from and command link to the AV. The smaller dish is used for passing selected imagery from the GCS into JDISS. The JDISS is a data dissemination and processing system that is located in the TS II. TS II requires 9 operators/maintainers and 1 C-141 for mobility. The Air Force will migrate to the Lightweight-Multi-band-Satellite-Terminal (LMST) when it becomes available. LMST requires only a pallet and a half for mobility.

2.4.175 Support Equipment Support equipment includes power generation, maintenance, testing, and troubleshooting equipment. Two 35 kw generators provide single and three phase power to the GCS. A fuel/de-fuel cart is used for each mission. An auxiliary power cart is used for powering the AV on the ground and AV startup. A portable hoist is used for lifting the AV in and out of the shipping container. A nickel-cadmium battery charger and maintenance tool kit are also included.


  2.5.1 General The Global Hawk (Tier II+) is optimized for supporting low-to-moderate threat, long endurance surveillance missions in which range, endurance, and time on station are paramount. The survivability of this vehicle is enhanced by its mission profile (i.e. high altitude and standoff). Flying at high altitudes (>50,000 ft) will make the vehicle more difficult to be engaged by hostile weapon systems. Additionally, standoff tactics will be employed where possible to avoid known threats and the use of early threat detection and warning capabilities (onboard and offboard) will assist with dynamic threat avoidance. These capabilities, coupled with the limited onboard electronic countermeasures and integrated composite force planning, will enhance survivability. Global Hawk requires a minimum complement of system components which include, air vehicles, sensor payloads, datalinks, launch and recovery element (LRE), portable launch and recovery element (PLRE), mission control element (MCE), support element (SE), and trained personnel. The HAE UAV ground segment, including the MCE, LRE, and PLRE, are common between Global Hawk and DarkStar. The prime contractor for Global Hawk is Teledyne Ryan Aeronautical. Other contractors include E-Systems for the ground segment, Hughes for the sensor payloads, Loral for communication links, and Boeing and GDE Systems Incorporated for mission planning.

  2.5.2 Mission Control Element (MCE) The MCE is the ground control station for both Global Hawk and DarkStar reconnaissance missions. It contains four workstations: the mission planning station, air vehicle operator, image quality control, and communications management. The mission commander will be a fifth operator responsible for overall mission management. The options of providing a dedicated mission commander workstation versus having the mission commander positioned behind the primary operators is still being evaluated. sensor data and processing station, air vehicle controller station, communication station and mission commander station. The MCE is composed of a standard shelter (with attached air conditioning equipment) which houses the crewmembers at their stations, dual generators to provide electrical power in the absence of compatible commercial sources, a Ku Band earth terminal, a MIST terminal for Common Data Link (CDL) operation, commercial satellite terminal, as well as terminals and antennas to LANs which provide theater communications. All equipment is intended to be air transportable in C-17, C-141, or C-1305 aircraft as part of the system deployment. Mission Planning Station The mission planning station generates an integrated mission plan consisting of a navigation plan, communications plan, sensor plan, and dissemination plan. During the mission, the mission planning station can initiate dynamic mission updates as required to ensure conformance with emergent tasking and clearances. These mission updates can range from retasking the sensor for a single image through replanning the entire mission plan including flight track, sensor plan, and/or dissemination plan. The MCE will have two Commander’s Tactical Terminal/Hybrid-Receive Only (CTT/HRs) to provide receive interfaces to the tactical intelligence broadcasts, including Tactical Reconnaissance Intelligence Exchange Service (TRIXS), Tactical Information Broadcast Service (TIBS), and Tactical Direct Dissemination System (TDDS)/Tactical Data Information Exchange System - Broadcast (TADIXS-B) networks. These threat data will be displayed to the AVO operator to provide NRT threat awareness. Threat data received from these sources will also be available to the mission planner. Ground communications will provide voice and/or data communications interfaces with theater communications networks for receipt of tasking, mission coordination (including tactical and airspace coordination circuits), and imagery/report dissemination. Circuits will include landline, LOS (UHF/VHF), and/or satellite. Planned communications capabilities include Public Switched Telephone Network (PSTN), STU-III, and AUTODIN. The ground communications will be compatible with current and future tactical and fixed communications systems and networks. Access to voice and data networks is the responsibility of the supported CINC. Sensor Data and Processing Station The Image Quality Control (QC) workstation will provide the capability to view imagery, monitor sensor status, initiate sensor calibration, and process/disseminate/store imagery. The image QC operator can view images to allow verification of sensor performance, as well as selected images for "quicklook" evaluation. Global Hawk SAR imagery will be "passed-through" the MCE processors, while EO/IR imagery will be mosaiced in the MCE’s Mercury processor prior to display and/or dissemination. Total processing time within the MCE prior to dissemination is expected to be less than 30 seconds. Primary imagery will be disseminated in NITFS 2.0 format with support data extensions at T-1 to T-3 rates (1.5 Mbps to 45 Mbps) and will be encrypted for transmission. T-1 rate imagery will be encrypted by KG-194A; T-3 rate imagery will be encrypted by KG-95-2. All received imagery will also be routed within the MCE to a Redundant Array of Inexpensive Discs (RAID) storage device; the RAID can store image data for up to 24 hours (at a 50 Mbps rate) and is designed as a backup should disseminated imagery not be received by the destination due to technical/ communications failure. This storage capability is not designed as an archive for user access. Pre-selected images will automatically be passed to the Joint Deployable Intelligence Support System (JDISS) processor for selected dissemination. The Global Hawk will also have the capability to provide unexploited imagery direct from the UAV to selected users. Exploitation will be accomplished through one or more existing or planned Department of Defense (DoD) imagery processing systems/installations including the Joint Services Imagery Processing System (JSIPS/JSIPS-N/JSIPS-TEG), Contingency Airborne Reconnaissance System (CARS), Modernized Imagery Exploitation System (MIES), and the Enhanced Tactical Radar Correlator (ETRAC). Exploitation might also occur at theater Joint Intelligence Centers (JICs) and Joint Analysis Center (JAC) or at CONUS-based production centers. Pending the modification of various exploitation systems to meet the CIG/SS architecture standards, a System Specific Interface (SSI) is being developed by Teledyne Ryan Aeronautical (TRA)/E-Systems for installation at supported exploitation sites during Phase II (CARS, ETRAC/MIES, JSIPS-N) to translate received HAE NITFS 2.0 imagery into the site-unique format. Air Vehicle Operator (AVO) Station The UAV operator is positioned within the MCE at the air vehicle operator station. Readouts of air vehicle position and flight instrumentation are displayed to the station operator at this position. From this station the AVO interfaces with air traffic control (ATC) and uplinks changes to the UAV if deviations from flight plan are necessary. The AVO position provides for continuous NRT monitoring of up to three air vehicles simultaneously, including air vehicle systems health and status, mission/threat status, and navigation, and allows the AVO to dynamically control the air vehicle flight path and systems operation. The AVO can modify the Global Hawk flight track through uplinking mission plan changes. Positive control of Global Hawk heading, altitude, or airspeed is provided to allow the operator to immediately respond to ATC/airspace coordination direction. The AVO will coordinate airspace management via a UHF/VHF voice relay through the air vehicle. The AVO will also control the aircraft threat warning and deception system and Identification Friend or Foe (IFF). Communications Control Station The communications specialist will operate the communications control station. The station will be equipped to maintain the health and status of all communication sub-systems. The communication specialist will be responsible for construction and monitoring of the communication plan, and redirection as required, as well as maintenance of the system. MCE communications includes all ground receive and transmit equipment to interface with both types of HAE air vehicles, as well as interfaces for theater communications. Air vehicle data links include a Ku Band terminal, Common Data Link (CDL) compatible LOS data link, and UHF SATCOM data links. All HAE data links are secure and have a voice channel for communications through a VHF/UHF voice relay (on the Global Hawk only). While this voice link is primarily for airspace coordination, it allows MCE/LRE/PLRE operators to talk through the air vehicle relay to anyone within LOS of the air vehicle, allowing use as a tactical circuit with Joint Surveillance Target Acquisition System (Joint STARS), Airborne Command and Control Center (ABCCC), Airborne Warning and Control Systems (AWACS), etc. MCE will incorporate an ARC-210 for direct LOS VHF/UHF voice communications with airspace control authorities. The Ku Band Tactical Field Terminal (TFT) uses a 6.25m dish antenna to provide for satellite communications relay C2 uplink, and down links of health and status and wideband imagery. The TFT can uplink to the air vehicle at 200 kbps and receive down links at 1.5, 10, 20, 30, 40, or 50 Mbps. The Modular Interoperable Surface Terminal (MIST) uses a 2m X-Band antenna to provide LOS C2 uplink, and health and status and wideband imagery down links. The MIST uplinks at 200 kbps, and receives down links at selectable rates of 1.5, 10.7, 137, or 274 Mpbs. For beyond LOS operations, the MCE has a Demand Assigned Multiple Access (DAMA) SATCOM for Global Hawk C2/health and status. The DAMA SATCOM provides for operation of up to three air vehicles simultaneously on the same data link.

  2.5.3 Launch and Recovery Element (LRE) The LRE is a subset of the MCE, providing the functionality for mission planning and air vehicle command and control. As depicted in Figure 2-1, the LRE contains a mission planning workstation and a command and control workstation. During split-site operations, the senior operator will function as the local mission commander until air vehicle control is passed to the MCE. The primary difference between the LRE and MCE is the lack of any wideband data links or image processing capability within the LRE and the addition of a Differential Global Positioning System (DGPS) system at the LRE to provide the precision navigation required for ground operations, take-off, and landing. The LRE mission planning capability is fully redundant with that in the MCE, which allows the LRE to make updates to the mission plan received from the MCE prior to launch or while enroute to/from the handover point; however, the LRE lacks provisions for automated reception of threat and weather data and will require these data from the MCE. Command and Control is executed over either the UHF SATCOM or LOS data links; voice coordination with airspace control authorities can be accomplished through the air vehicle relay (over UHF SATCOM only, and only through the Global Hawk) or via a dedicated ARC-210 VHF/UHF voice radio. The UHF SATCOM and LOS radios are interchangeable, providing an in-line spare for both links. Take-off and landing accuracy is obtained using DGPS; the DGPS system computes pseudo-range corrections to received GPS signals and transmits those corrections to the air vehicle, providing accuracy’s of 1.1 meter within 20 nm of the LRE. The pseudo-range corrections are transmitted over a separate VHF link for Global Hawk, and are integrated into to C2 uplink signal for DarkStar. (DarkStar does have a separate backup VHF link for DGPS corrections should the C2 link fail). The Global Hawk DGPS is designed for Special Category One (SCAT-1) operation. Once SCAT-1 systems become available and their use widespread, Global Hawk should be able to land at any airfield with an operable system, providing readily available alternative landing sites.

Figure 2-1 HAE Launch and Recovery Element Portable Launch and Recovery Element (PLRE) A small quantity of PLREs will be available for deployment to the supported AOR as necessary in order to manage alternate UAV recovery options. The actual size and composition of this element is undergoing development and will be more clearly defined as the ACTD progresses.


2.5.4 Air Vehicle The air vehicle operation will be essentially autonomous using fail safe programs with the capability of being reprogrammed in flight should changes to its flight plan be required. System redundancy for selected systems will greatly reduce the probability of loss and allow extended time on missions while a replacement vehicle is enroute. GPS aided inertial navigation systems provide the accuracy required for both runway environment and flight operations. The vehicle is equipped with an automatic takeoff and landing (no man-in-the-loop) system capable of handling a cross-wind component of 20 knots and permitting operations from a >5000 foot improved runway in zero zero surface weather conditions. Accuracy is enhanced with differential GPS (DGPS) and a radar altimeter.




Operating Radius

3000 NM

Operating Altitude

>50,000 (Flight Level (FL) 500) 65,000 ft (Flight Level (FL) 650)

True Air Speed

300 - 400 Knots

Time on Station

24 Hours at Operating Radius/Altitude

Fuel Reserve

1 Hour

Table 2-2: Global Hawk Operational Planning Factors 

2.5.5 Air Vehicle Signature The air vehicle has not been specifically designed to offer a reduced signature and actual signature has not been determined. To enhance Global Hawk survivability, it is equipped with the AN/ALR-89(V) Threat Warning Receiver (TWR), a Threat Deception System (TDS) including onboard jammers, appliques, and expendable decoys, and the ALE-50 Towed Decoy System. These survivability systems are capable of manual or fully automated operation, either as independent systems or as a single integrated survivability suite. The TWR is fully integrated into the flight computer to provide automatic maneuvering of the air vehicle to minimize detected threats.

2.5.6 Weather Effects The vehicle is fully capable of operating in zero zero surface weather conditions and has an anti-skid braking system to reduce the problems associated with lowered runway condition readings (RCR). Wing spoilers aid in speed and roll control permitting operation in crosswind components of 20 knots. The rapid rate of climb through 25,000 feet reduces the time spent at ice producing altitudes and minimizes the amount of accretion on flight surfaces which will sublimate at higher altitudes. Vehicle speed during climb through the jet stream is sufficient to cope with the winds which will not be a factor during cruise at altitude. Large control surfaces and fly by wire reaction enable the autopilot to successfully attenuate the effects of high altitude clear air turbulence. Thunderstorms will rarely be encountered at mission altitudes but if forecast, will be circumvented if the cells are observed through on board sensors. Thunderstorm activity during climb and descent will be avoided by 20 NM through vectors provided to the LRE controller by local RAPCONs and ATC enroute radars. Descent through icing conditions will be rapid with the very low wing loading minimizing the effects of any substantial accretion. Specific icing and turbulence limitations will need to be established during flight testing and will be defined in technical data produced at the conclusion of the ACTD. The very long endurance and range give operators time to consider many options for safe recovery while still performing the mission should forecasts or conditions change drastically.

2.5.7 Propulsion The engine is a modified version of the commercial Allison AE3007 which produces 7,200 lbs thrust at sea level. The engine does not require special fuel and will operate on fuels from base POL sources used with other Air Force jet aircraft.

2.5.8 Avionics The avionics package includes automatic controls for taxi, takeoff, navigation and systems control through out the flight profile, sensor and communications functions, redundancy and flight systems management, return to base, landing, and taxi clear of runway. The UAV is equipped with an integrated Inertial Navigation System (INS) aided by the Global Positioning System (GPS) for controlling the auto pilot, and an IFF transponder with mode "C." Differential GPS and a radar altimeter is used to ensure runway environment accuracy, for taxi, take off and landing.

2.5.9 Sensor Payloads The baseline payload incorporates EO, IR, and SAR imagery sensors. All three imagery sensors are to be carried simultaneously and be capable of operating either the EO or IR sensor simultaneously with the SAR. Only data from one sensor at a time can be downlinked. The coverage objective may be interleaved as to area and spot coverage and by SAR and/or EO/IR sensors. Various special use sensor payloads may be added to the imagery payload depending on mission requirements. EO/IR The EO/IR sensors will operate in Wide Area Search, Spot Collection, Point Target (continuous stare), and Stereo Modes, providing a National Imagery Interpretability Rating Scale (NIIRS) rating capability of at least 6 for the EO (NIIRS 5 for DarkStar) and 5 for the IR, measured at 45 degrees depression from the horizontal, while in the Wide Area Search Mode. The Hughes IR aboard operates in the 3-5 micron spectrum. EO/IR pixel data will be processed aboard the air vehicle and transmitted as 1k x 1k image frames (EO) or 640 x 480 image frames (IR) in NITFS 2.0 format. These image frames will be mosaiced in the MCE (140 EO frames/spot image, 98 IR frames/spot image) prior to dissemination. SAR The SAR operates in the X-Band and has a Ground Moving Target Indicator (GMTI) mode with a minimum detectable velocity of 4 knots. The SAR sensor has the capability to image with 1 meter resolution in the search mode and 0.3 meter resolution in the spot mode. Maximum imaging range is 200 km. Data is processed onboard the aircraft and transmitted as uncompressed (8 bpp) or compressed (2bpp) images. Compression uses Joint Photographic Experts Group (JPEG) compression algorithms. Images are transmitted in NITFS 2.0 format with support data extensions (SDE); SAR wide area search (WAS) images are segmented. GMTI data are transmitted as a text product providing location and range velocity. Special Use Payloads The Global Hawk will have the capability to carry special use payloads to include: communications relay, signal intelligence (SIGINT), measurement and signal intelligence (MASINT), air sampling, and cartographic imagery sensors. These payloads and missions for Global Hawk are in the idea stage and not part of this CONOPS.

2.5.10 Datalink Command and Control Command and control communications to and from the aircraft will be accomplished using UHF DAMA satellite channels (MCE, LRE, and PLRE) or non-DAMA LOS (LRE and PLRE only) duplex data links at 1.2 kbps, or through the Ku Band SATCOM or LOS CDL at 200 kbps (MCE only). The UHF DAMA capability will allow the MCE to control and monitor health and status from three air vehicles simultaneously over a single data link. Appropriately equipped exploitation stations (afloat and ashore) will be able to utilize the Ku Band and CDL links to directly control the onboard sensors when tactically directed. In addition to the C2 commands, the UHF and Ku SATCOM and CDL LOS data links carry digitized voice data for relay through the onboard VHF/UHF voice relays to allow over-the-horizon communications with tactical or airspace control authorities within LOS of the air vehicle. Sensor Datalinks The program objective is to have untethered worldwide operations using a satellite link for sending sensor data from the aircraft to the MCE. All data links will be encrypted for security and will be designed to minimize susceptibility to jamming and interception. The system provides continuous duplex command and control communications with the air vehicles via satellite and line-of-sight data links. These links will allow dynamic mission updates in flight and continuous monitoring of the health and status of the aircraft and subsystems by both the MCE, LRE, and PLRE. The UAVs can utilize either the LOS CDL or the Ku Band commercial satellite data link to transmit sensor data back to the MCE. Global Hawk will transmit sensor data at up to 137 Mbps over CDL and will transmit at rates between 1.5 and 50 Mbps over the Ku Band. Dissemination of imagery will be directly to appropriately equipped exploitation systems and tactical field users at selectable rates from 1.5 Mbps to 137 Mbps depending on the capacity of the available link and capability of the ground receive terminal. Global Hawk will also carry an Ampex DCRsI-75 onboard recorder capable of recording up to 2 hours (at 50 Mbps rate) of wide area search imagery, with the capability to down links from the recorder upon command. The system is compliant with the CIG/SS architecture and will provide processed imagery from the air vehicle in NITFS 2.0 format with SDE. SAR data will be transmitted as formed images; EO/IR imagery data will be transmitted as 1k x 1k frames and mosaiced in the MCE.

2.5.11 Support Equipment The ground support segment includes all equipment required to operate and maintain the system, spare and repair parts, and personnel trained to maintain the air vehicles and ground elements. Support equipment includes 30- and 90-kw power generators, trailers, maintenance vans, test equipment, and tools. The support segment will include all equipment required to perform system, segment, and subsystem checkout, ground test, and end-to-end testing. Maximum use will be made of Built-in-Test Equipment (BITE). The use of special test and ground support equipment to support system components has been minimized. Adapters and interface devices will be included in the basic system design to allow use of common support and test equipment available at deployed locations. Spare and repair parts will be provided as pack-up kits or Mission Spares Kits (MSKs) and include parts to support the air vehicle, MCE, GCE, and LRE. MSKs for deployed operations will include sufficient spares for 30 days of continuous operations. Specific logistics considerations are discussed in Section 9. Maintenance manpower will be adequate to support 4-hour air vehicle turnaround, along with required preventative and corrective maintenance on all HAE system components. Section 8 discusses specific manpower and training issues and capabilities.


  2.6.1 General The Tier III- has been nicknamed "DarkStar". This class of high altitude UAV is being designed to penetrate into high threat areas where there is high risk to the Global Hawk vehicles. This vehicle is designed for low observability and is optimized for moderate endurance, high-threat reconnaissance missions in which ensured coverage is more important than range and endurance. The DarkStar mission requires a minimum compliment of an system is composed of air vehicles, sensor payloads, datalinks, launch and recovery element (LRE), portable launch and recovery element (PLRE), mission control element (MCE), support element (SE), and trained personnel. The prime contractor for the DarkStar is Lockheed Martin Skunk Works with Boeing Military Aircraft Division as a major sub-contractor for the initial ground control and processing equipment. The Tier III- has been nicknamed "Dark Star".

2.6.2 Mission Control Element (MCE) The MCE is common to both the Global Hawk and DarkStar UAVs. Reference Para 2.5.2 for MCE capabilities and description. Mission Planning Station See Para for mission planning commonality with Global Hawk. DarkStar does not have the same positive control capability for redirecting vehicle flight path as Global Hawk. DarkStar mission track changes required to respond to ATC direction, or ad hoc mission retasking, are commanded by sending updated "waypoint" data to the UAV. Data Exploitation Station See Para for data exploitation commonality with Global Hawk. DarkStar SAR and EO imagery is ground processed and formatted into National Imagery Transmission Format Standard (NITFS) 2.0 format prior to display and/or dissemination. Total processing time with the MCE prior to dissemination is expected to be less than 30 seconds. Air Vehicle Operator Station See Para, same as Global Hawk. Communications Control Station See Para, for communications commonality with Global Hawk. DarkStar does not have a voice channel for communications through a VHF/UHF relay allowing communications through the vehicle to other ground or airborne sites. Tactical Field Terminal (TFT) will neither uplink to the DarkStar nor deliver DarkStar imagery at rates greater than 1.5 Mbps because of air vehicle system design. A non-DAMA SATCOM is used for DarkStar C2/health and status.

2.6.3 Air Vehicle The DarkStar is made of graphite composite for low weight, and has a 69-foot span and 15-foot length. The zero fuel weight with the radar payload is 5,640 lb., and the electro-optical payload is about 200 lb. lighter. It is capable of fully autonomous operations once programmed by the ground stations, including fully automatic taxi, take-off, flight, and recovery. Aircraft system, sensor, and navigational status is provided continuously to the ground operators through health and status down links for mission monitoring, and the navigation and sensor plans updated in flight. The air vehicle has multiple contingency modes to provide safe, predictable operation in the event of lost data links, mission critical equipment, or flight critical equipment. Navigation is via inertial navigation with integrated GPS updates. Taxi, take-off, and landing accuracy is enhanced with DGPS and a laser altimeter. It is capable of operating from a 5,000 foot runway in a 20 kt crosswind. DarkStar’s limited range and unique DGPS system require it to operate only from a field where the LCRS, LRE, or PLRE is located and will normally be transported into theater.


DarkStar (Tier III Minus)

Operating Radius

>500 NM

Operating Altitude

>45,000 FT (FL 450)

True Air Speed

>250 Knots

Time on Station

>8 Hours

Fuel Reserve

>30 Minutes

Table 2-3: DarkStar Operational Planning Factors Flight Characteristics

2.6.4 Air Vehicle Signature DarkStar’s signature is currently classified.

2.6.5 Weather Effects TBD.

2.6.6 Propulsion "DarkStar" is powered by a Williams FJ44 turbojet engine producing 1,900 lbs. of sea-level static thrust.

2.6.7 Avionics To Be Added.

2.6.8 Sensor Payloads The DarkStar has the capability of carrying either an EO or SAR sensor (single sensor carriage). An IR capability is not currently planned for this vehicle. Maintenance personnel will be able to swap sensors with normal tools in field conditions at MOB and Non-MOB locations the FOL. This is to support both the dynamic conditions of the battlefield and to allow units flexibility due to unplanned (unforecasted) weather changes. EO The EO sensor will provide a NIIRS rating capability of 6, measured at 45 degrees depression from the horizontal. DarkStar will produce EO data in a nonstandard multiplexed format or as compressed pixels; accordingly, all DarkStar imagery will be transmitted to the MCE for processing and formatting prior to storage within the MCE or dissemination. SAR The SAR sensor will produce imagery with 1 meter resolution in the search mode and provide .3 meter resolution in the spot mode. It will also have a Ground Moving Target Indication (GMTI) mode with a minimum detectable velocity of 4 knots. DarkStar will provide SAR data as video phase history or compressed pixels for ground processing within the MCE.

2.6.9 Datalink Command and Control See para 2.5..109.1, for commonality with Global Hawk. Command and control for DarkStar is accomplished through non-DAMA UHF Milsat or LOS data links at 2.4 kbps or through the CDL at 200 kbps. The DarkStar does not have the capability for Ku Band uplink, remote sensor control, or voice relay. Sensor Datalinks The objective is to have untethered worldwide operations using a satellite link for sending sensor data from the aircraft to the MCE. DarkStar’s Ku SATCOM is spread-spectrum and transmits at 1.5 Mbps. It is envisioned that data rates up to >100 Mbit/second are achievable via commercial satellite (e.g. PANAMSAT or INTELSAT). A second method for receipt of sensor data at the MCE will be through the CDL when the UAV is operating within LOS. DarkStar provides sensor data to the MCE for processing and then retransmit processed/compressed data to theater and/or national sites for intelligence exploitation. An alternative concept and the preferred method is to data link directly from the UAV to a theater exploitation site. However, this concept depends on some on board processing capability and low observable data link antenna. Feasibility of this concept has not been determined.

  2.6.10 Support Equipment See para 2.5.11, same as Global Hawk. 

2.7 Future UAV Payload Modifications.

2.7.1 Follow-on missions for all UAVs are envisioned to include a range of advanced SIGINT applications. Concepts for ISR SIGINT and MASINT applications are being developed and will come under a separate cover.

2.7.2 The Air force Communications Agency is currently sponsoring a contractor study of the feasibility of using Global Hawk HAE UAV as a communications relay platform, with participation from Air Staff, Air Combat Command, Air Mobility Command, Air Force Special Operations Command, and the Defense Information Systems Agency for post integration. The four highest priority payload applications under evaluation are surrogate satellite (UHF and SHF), Communications bridging (interoperability), trunking concentrator (virtual ABCCC), and JTIDS Link 16.

2.7.3 Mid to long term modifications to UAV payloads could include equipment and weapons to accomplish the Suppression of Enemy Air Defenses (SEAD) and Interdiction missions. These mission areas are outside the ISR mission area and should be studied by the AF UAV Battle Lab.



Global Hawk


Gross Take-off Weight

>1873 lbs (EO/IR)

22,914 lbs

8,600 lbs


48.7 feet

116.2 feet

69 feet

Mission Duration

Operating Radius

24+ hours on station

@ 500 NM

24 hours on station

@3000 NM

> 8 hours on station

@ 500 NM

Maximum Endurance

40+ hours

42+ hours


Ferry Range


15,000 NM



>450 lbs

2,000 lbs

1,000 lbs

True Air Speed

60-110 knots

350 knots

>250 knots

Loiter altitude

25,000 feet max.

15,000 Feet Nominal

>50,000 feet

>45,000 feet

Survivability Measures


Threat warning and ECM

Very low observable

Command and Control





SAR: 1 ft IPR, Swath Width Approx. 800 m



Simultaneous Dual Carriage

SAR: 1 m search; 0.3 m spot



Simultaneous Dual Carriage

SAR: 1 m search 0.3 m spot


IR: None

Single Carriage

Coverage per mission

13,000 sq NM search imagery

40,000 sq. NM. search imagery, or
1,900 spot image frames

14,000 sq. NM search imagery, or
620 spot image frames

Sensor data transmission

Ku Band: 1.5 Mb/sec


LOS: C-band 4.5Mb/sec

Wide band COMSAT: 20-50 Mbits/sec

LOS: X-Band Wide Band (CDL): 137-275 Mbits/sec

Narrow band COMSAT: 1.5 Mbits/sec

LOS: X-Band Wide band (CDLS): 137-275 Mbits/sec


6 C-141s or 10 C-130s


Self deployable, SE requires airlift

3 C-141s or Multiple


Ground Control Station



Maximum use of GOTS/COTS (LOS & OTH)

Common with Tier II Plus

Data Exploitation

Existing and Programmed:

Existing and Programmed:

Existing and Programmed:


Table 2-4: Comparison of Endurance UAV Key Capabilities