PBO/ALFS CABLE

AIRBORN LOW FREQUENCY SONAR (ALFS) CABLES MADE WITH CURRENT STATE-OF-THE-ART MATERIALS MAKE PRECISE DEPTH CONTROL DIFFICULT AND THREATEN HELICOPTER SAFETY DURING RETRIEVAL. STRETCH CAN BE LIMITED BY REDUCING STRESS (LARGER DIAMETER) BUT THIS ADDS UNACCEPTABLE WEIGHT AND HANDLING CHARACTERISTICS, PARTICULARLY AT COLD TEMPERATURES. A NEW CABLE DESIGNED FOR MINIMUM STRETCH AND USING A NEW ULTRAHIGH MODULUS/HIGH STRENGTH LIQUID CRYSTAL ORDERED POLYMER WILL REDUCE CABLE DIAMETER (AND WEIGHT) TO A NEW MINIMUM AND ELIMINATE CURRENT ELASTICITY AND HANDLING PROBLEMS. WE BELIEVE THIS NEW CABLE WILL BE 30 PERCENT SMALLER IN DIAMETER AND 50 PERCENT LIGHTER THAN THE CURRENT 8.4 MM DIAMETER KEVLAR CABLE. THE PROPOSED PHASE I PROGRAM WILL DESIGN A MINIMUM STRETCH/MINIMUM WEIGHT CABLE CONSISTENT WITH NAVY PERFORMANCE REQUREMENTS USING POLY-P-PHENYLENE BENZOBISOXAZOLE (PBO) FIBER. A SAMPLE CABLE WILL BE FABRICATED BY NEW ENGLAND ROPES, TESTED AND EVALUATED BY FOSTER-MILLER FOR PERFORMANCE AND TO RECOMMEND PHASE II IMPROVEMENTS. THE SUCCESSFUL TEST PROGRAM WILL FORM THE BASIS OF A PHASE II PROGRAM THAT WILL OPTIMIZE THE CABLE DESIGN AND FABRICATE AND TEST A FULL-SCALE PROTOTYPE ALFS CABLE THAT WILL BE DELIVERED TO NADC.