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	Director, Operational Test & Evaluation
	FY98 Annual Report

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The mission of the medium altitude endurance unmanned aerial vehicle (UAV) system is to provide cued and non-cued reconnaissance, surveillance, and targeting capability. The system can operate autonomously, is attritable (air vehicle cost is less than $3.5M), and does not compromise sensitive technology should it be lost over enemy territory. The RQ-1A will enable the in-theater CINC to contribute to the Joint Vision 2010 concept of dominant maneuver by providing information superiority.

The Predator system comprises both air and ground segments; it is intended to provide the Theater or Joint Task Force Commander with continuous imagery coverage of small, fixed, or mobile targets. The system will be required to operate in less than ideal weather conditions and has the capability to incorporate a wet-wing de-icing system for transit through moderate icing conditions.

The air segment consists of four propeller-driven full composite air vehicles, each with Electro-Optic, Infrared and Synthetic Aperture Radar sensor payloads. The RQ-1A will fly at altitudes up to 25,000 feet MSL. Data link systems between the air vehicle and the ground system include C-band line-of-sight and Ku-band satellite for operations beyond line-of-sight.

The ground segment consists of a shelter containing the Ground Control Station (GCS) and a High Mobility Multi-Purpose Wheeled Vehicle-based Trojan Spirit II satellite communications system. In addition, the ground segment also contains a 2.4-meter mobile antenna for imagery dissemination and a 5.5-meter antenna for air vehicle satellite communications.

In August 1997, the Predator completed its transition from an Advanced Concept Technology Demonstration (ACTD) to an ACAT II acquisition program. Six systems and 21 air vehicles are residuals from the ACTD. Also in 1997, two more systems with four air vehicles each were purchased. A 1998 contract procured two systems with four air vehicles each and 11 attrition air vehicles. These contracts bring the total number of systems delivered (or under contract) to ten. The final two systems, for a total force structure of 12 systems, will be procured after IOT&E scheduled for 4QFY99.

The Air Force Operational Requirements Document (ORD), approved in July 1997, delineated a number of system upgrades with the top priorities being: (1) a de-icing capability; (2) a UHF/VHF radio link for air traffic control through the air vehicle; (3) improved IFF transponders; and (4) a repackaged GCS. Other system capabilities that define the baseline system, and are scheduled to be included prior to operational test, include the more powerful Rotax 914 engine, relief on station (ROS) capability, and reliability improvements. Predator system number six will be the first system retrofitted with all the baseline capabilities, and will be used for initial OT. The Air Force's 11^th Reconnaissance Squadron received the fifth Predator system this year. Three systems are now operational at the 11^th RS training site at Indian Springs, NV; one is operating in Hungary and the other is supporting technical testing at the contractor's California facility.

DOT&E approved the TEMP in August 1998, with a letter specifying changes to be included in the next revision. The test strategy will maintain the streamlined acquisition nature of the Predator ACTD and evaluate the key critical areas not assessed during the ACTD and new system modifications. The basic scenario for IOT&E will consist of continuous operations for two five-day periods, featuring daily missions and ad hoc taskings, designed to assess continuous coverage capability. An end to end assessment will be conducted to determine the usefulness of the imagery products.

Flight performance characterization continued this year with the new turbo charged Rotax 914 engine and both wet and dry wing sets. During these flights, sensor performance (EO/IR/SAR) and target location data were collected. Demonstrations of multiple air vehicle control by a single GCS (relief on station) took place this year. AFOTEC conducted radar cross section (RCS) measurements at Indian Springs in April and May 1998, and also completed some survivability modeling for one-on-one and mission-level scenarios using the RCS data. Several live flights on the Nellis ranges against representative threats will be conducted in September to validate the model results. Incorporation of the ATC voice radio and new IFF transponders have been hampered by frequent delays; flight-testing is now scheduled to begin in October of this year.

The 11^th RS re-deployed to Hungary in March 1998 after standing down for the winter months. Mission data from March 1996-December 1997 were collected and assessed for mission completion rates and operational reliability.

The AFOTEC OA Report, dated June 15, 1998, evaluated current Predator capabilities and matched them against ORD thresholds to identify areas of risk prior to IOT&E. A Joint Reliability, Maintainability, and Evaluation Team (JRMET) evaluated data collected from Hungary, Indian Springs, and the contractor facility to determine current system suitability parameters.

The Predator demonstrated flight endurances of 21 hours 49 minutes with wet wings and 30 hours 18 minutes with dry wings. A technical demonstration of the capability to conduct emergency procedures using two air vehicles and one GCS was successful; however, full operational implementation of the ROS capability is not viable because of limitations integrating the data link with the ground station.

The operational mission data indicated that nearly half of all tasked missions in-theater between March 1996 and December 1997 were affected by weather. The primary weather factors were icing (12 percent of tasked missions) and conditions precluding takeoff minimums (visibility and ceiling, 10 percent of tasked missions). The newly developed de-icing system may alleviate some mission aborts by providing the capability to transit icing layers; however, given the overall flight performance capabilities of the Predator, it is unlikely that the operators would launch an air vehicle if icy conditions persisted in the local or target areas. An overall improvement in mission accomplishment, as a result of an operational de-icing system, would more than likely be less than 10 percent, leaving about 40 percent of the missions still affected by the weather.

Twelve percent of tasked missions during the same time period were affected by system failures, with the primary system failures being the air data systems and the engine. The average mission duration was 10.9 hours with an observed mission reliability of 74 percent. (Mission reliability is defined as the fraction of missions completed without system abort-excluding weather-affected missions.) For the 25-hour missions prescribed in the ORD, current data predict mission reliability of less than 50 percent. There has been reliability growth since the system first deployed in March 1996. Although the growth was quite large in the first few months, it has only shown a slight increase since then. Reliability at the end of deployment (December 1997) was estimated to be 36 hours mean time between mission affecting failure. (The ORD requirement is 40 hours.)

The Military Aircraft Sustainability Simulation (MASS) was developed by DOT&E to predict effective time-on-station (ETOS) rates based on observed or desired reliability, maintenance, and endurance values. The Predator ETOS requirement is 75 percent on station at 400 miles from base. Using data from the JRMET, MASS predicted about 60 percent ETOS without relief-on-station and 80 percent ETOS with relief-on-station using an air vehicle endurance of 33 hours and a reliability of 40 hours mean time between mission affecting failures. These results should be considered somewhat optimistic because they assume complete spares availability and ORD values (not demonstrated values) for other suitability parameters such as mean time to repair and mean time between non-essential maintenance action. In addition, the flights used to collect the JRMET data were significantly shorter than the air vehicle endurance. Thus, the demonstrated failure rates may be lower than should be expected for longer flights.

The Predator has demonstrated that it can sufficiently perform a multitude of Reconnaissance, Surveillance, and Target Acquisition missions. Although the system has demonstrated several capabilities, some functions, such as autonomous flight, sensor data recording, and adverse weather operations, require more work. The system has shown the potential to be maintained and logistically supported in the field, but the lack of sound data collection procedures in the field precluded an operationally representative assessment. This will be addressed during the upcoming IOT&E.

The Predator is similar to other general aviation aircraft in that adverse weather will significantly impact its flight operation. Even with the introduction of a de-icing system, weather phenomena such as icing and takeoff minimums will reduce the fraction of tasked flights able to be completed.

The ability to collect system sustainability data over a long period of time; i.e., during operations, training, and technical testing (in addition to the relatively short period of time during an operational test) increases the knowledge of the system's capability and helps reduce risk prior to IOT&E.

The use of sustainability data collected in the field, coupled with the MASS simulation developed by DOT&E, provided insight not otherwise available for Predator's target coverage rate. Since relief-on-station may not be operationally realistic for some time, the ETOS model can be used to predict the levels of target coverage during the absence or presence of relief-on-station.