AIRBORNE LASER GENERATED LOW FREQUENCY SOUND FOR ASW APPLICATION

THE DETECTION AND LOCALIZATION PHASES OF AIRBORNE ANTISUBMARINE WARFARE (ASW) HAVE, IN THE PAST, RELIED HEAVILY ON PINGER OR EXPLOSIVE ACTIVE ADJUNCTS TO THE PASSIVE SONOBUOYS OR TO ACTIVE SONOBUOYS. BOTH OF THESE REQUIRE EXPENSIVE EXPENDABLES WHICH SEVERLY LIMIT THE DATA RATE. THIS PHASE I PROPOSAL IS TO DETERMINE THE FEASIBILITY OF USING LASER PULSES FROM THE AIRCRAFT TO GENERATE LOW FREQUENCY SOUND FOR SUBMARINE DETECTION AND LOCALIZATION AND FOR OTHER NAVAL APPLICATIONS. PHASE II IS TO DEVELOP THE TECHNOLOGY AND DEMONSTRATE THE CONCEPT. THE OVERALL OBJECTIVE OF THIS PHASE I PROGRAM IS TO DETERMINE THE FEASIBILITY OF GENERATING USEFUL SONAR PULSES IN WATER FROM AIRBORNE LASERS AND THEN TO SCALE THOSE RESULTS TO AN OPERATIONAL AIRCRAFT SCENARIO TO DETERMINE THE ECONOMIC AND PRACTICAL FEASIBILITY OF THE CONCEPT. SPECIFICALLY, THE FIRST OBJECTIVE IS TO MEASURE THE SOUND AS A FUNCTION OF THE TEMPORAL SHAPE, THE TOTAL ENERGY, THE ENERGY DENSITY (SPOT SIZE), AND THE PULSE LENGTH OF THE PULSE. ANOTHER OBJECTIVE IS TO DETERMINE THE LOW FREQUENCY CONTENT OF THE ACOUSTIC PULSE GENERATED BY THE SPECIAL LASER PULSE TECHNIQUE. A FINAL OBJECTIVE IS TO DEVELOP A CONCEPTUAL DESIGN OF AN AIRBORNE SYSTEM AND ESTIMATE THE SYSTEM COST AND PERFORMANCE.