Office of Naval Research, 800 North Quincy St., Arlington, VA 22217-5660

R -- 58- AIRCRAFT ALERT RADAR SYSTEM DUE 121298 POC Business POC -- Susan Vilello, Contracting Officer (703) 696-2605 and Technical POC -- Edward Kennedy, Program Officer, (202) 767-2761 The Office of Naval Research (ONR) may have a requirement for an aircraft alert radar for the High-frequency Active Auroral Research Program (HAARP) and thus is seeking potential sources to provide the radar. The High-frequency Active Auroral Research Program is located in Alaska and is a state-of-the-art facility for the active study of the Earth's ionosphere and its effects on radio systems. The facility is on DoD-owned property near Gakona, Alaska about 180 miles east-northeast of Anchorage. Among the active instruments on the site is a prototype 360-kilowatt high frequency (HF) phased array, which was completed in 1996. By the end of calendar 1998 it is expected that the HF power will be increased to 960 kilowatts, and at completion (date currently unknown) the transmitting array will be capable of sending up to 3.6 million watts toward selected portions of the overhead ionosphere. Therefore, an aircraft alert radar is needed to detect aircraft on flight tracks that would intersect a specified "risk volume" above the facility, and automatically shut down the HF transmitters until such aircraft either turn to a non-intersecting track or exit the risk volume. This risk has the form of an inverted truncated cone centered on the array. At 100-meter (328 feet) altitude the radius of the truncated portion of the risk volume cone is 250 meters (820 feet). The risk volume ends at approximately 6500 meter (21,325 feet) altitude where the radius of the risk volume cone is 2600 meters (8530 feet). The radius of the risk volume cone at 10,000 feet is 2000 meters (6562 feet). At lower altitudes (less than 10,000 feet), general aviation visual flight rule (VFR) aircraft likely will comprise the dominant population. A small "rag and tube" aircraft may have a radar cross-section of one square meter. General aviation aircraft flying below 10,000 feet altitude could approach the site at speeds up to 180 knots. At middle and higher altitudes (greater than 10,000 feet) aircraft flying on established airways and on instrument flight rules (IFR) likely will comprise the dominant population. Business jets likely will be the smallest of the aircraft population at these altitudes. The expected radar cross section of the business jets nominally is three square meters. These aircraft could approach at a speed of 450 knots. Desired aircraft detection criteria: 360 degree azimuthal coverage; detection shall be at least 30 seconds prior to entering the risk volume. (At the top of the risk volume, the 30-second requirement corresponds to a radial range of approximately 5.2 nautical miles (31,330 feet) for an aircraft speed of 450 knots. At 10,000 feet altitude, the radial range is approximately 4.8 nautical miles (29,360 feet). At 100-meter (328 feet) altitude, the radial range is approximately 1.6 nautical miles (9,940 feet) at an aircraft speed of 180 knots.) Probability of Missed Detection: less than one in a million. Time between False Alarms: at least 10 hours. (A False Alarm is defined as a radar return(s) that has aircraft-like characteristics, has an inbound Doppler, is declared to be an aircraft, yet is not an aircraft.) Environmental and Siting Considerations: Detection shall be in the presence of ground clutter characteristic of the Gakona, Alaska site. Detection shall be in the presence of a rain rate of up to three millimeters per hour. The radar shall operate in winds up to and including 35 knots, survive winds of 75 knots with one-half inch of radial ice. and operate over the temperature range of 90 degrees to a low of minus 55 degrees Fahrenheit and survive a cold soak at minus 70 degrees Fahrenheit. The radar shall perform with the HF (2.8-10 MHz) transmitters and a UHF (nominally 425 MHz) incoherent scatter radar both operating and be sited within 2000 feet of the edge of the HF antenna array and within 2000 feet of the UHF incoherent scatter radar. The Gakona Alaska site is on a migratory bird route for larger birds such as geese and swans. The radar shall be operated whenever the HF transmitters are tested at high power or when science campaigns are conducted. These tests and operating periods are expected to occur approximately five times per year with duration of two weeks for each period. During these periods, the transmitters and the radar shall operate for an average of ten hours per day. The radar shall be secured in a stored mode during the non-operating periods of the transmitters, be available 95% of the time for the test and science campaign periods, and be maintainable by an electronic technician who will have the ability to remove and replace failed parts. The failed parts will be returned to the supplier for repair. Interest parties should submit the following information as a minimum: 1) radar system specifications, to include frequency of operation, peak and average power, environmental temperature operating range, size, weights of component parts; 2) an analysis demonstrating that all required detection criteria are met by the proposed radar system; 3) price and delivery schedule; and 4) warranty information.The information is due 30 days after the date of this announcement to the attention of Mr. Edward Kennedy at the Naval Research Laboratory, Code 5550, 4555 Overlook Avenue, S.W. Washington, DC 20375-5320. This announcement is not a solicitation, only a request for information. However, based on the information received in response to this announcement, a solicitation for an aircraft alert radar system may be issued. Posted 11/10/98 (W-SN270274). (0314)

Loren Data Corp. http://www.ld.com (SYN# 0098 19981113\R-0024.SOL)