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User Test of Beacon, Light, Pathfinder, Project Nr AB 2059 and AVN 2360

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The Beacon, Light, Pathfinder, was erected at two widely separated sites on the Fort Rucker, Alabama, Military Reservation. Numerous combinations of lens colors and code signals were incorporated on separate tests in an effort to include each lens emission on continuous beam, automatic code, and manually operated code. The basic altitude flown by the Army aviators evaluating the test item was 1,000 feet above the terrain. However, in an effort to insure completeness of test, selected altitudes above and below 1,000 feet absolute were flown. Distances at which lights were first visible varied to some degree by the altitude being flown. On clear, moonless nights, while flying at an absolute altitude of 1,000 feet, red, clear, and amber lights were clearly distinguishable at distances up to approximately 10 statute miles. Discernibleness of color emissions of the test item ranged in effectiveness in order from red, clear, amber, green, to blue. Red emissions were often discernible at the range at which the test item was first attracted to the view of the aviators. The signals emitted from the beacons were readable at somewhat shorter ranges than the extreme limits of air-to-ground viewing limits. The lag between original sighting and readability appears to be geared to adaptability of the observer to signal interpretation. Signal emissions appeared to have the same effect as a flashing beacon in attracting the aviators attention. The test item appears to have excellent terminal aid potential under non-tactical conditions. The lights when coded flashing were visible and attracted the aviators at ranges in excess of five statute miles and at absolute altitudes of 1,000 feet.

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  • Terminal Flight Facilities

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