THE USE OF ALTERNATIVE REFRIGERANTS FOR MISSILE GUIDANCE COOLING SYSTEMS

THE U.S. AIR FORCE IS PRESENTLY PREPARING PLANS FOR THE PHASE OUT OF ATMOSPHERIC OZONE DEPLETING SUBSTANCES, SUCH AS CFC AND HCFC REFRIGERANTS. ONE OF THE MORE DIFFICULT APPLICATIONS TO ADDRESS IS THE COOLING COMPONENTS ASSOCIATED WITH GUIDED MISSILE WEAPON SYSTEMS, WHICH PRESENTLY EMPLOY EITHER CFC-12 OR HCFC-22. FINDING SUITABLE ZERO ODP SUBSTITUTE REFRIGERANTS FOR THESE APPLICATIONS IS PARTICULARLY DIFFICULT, BECAUSE MUCH OF THE COOLING IS UNIQUE TO GUIDED MISSILES AND THE HARDWARE IS INTEGRAL TO THE ENTIRE WEAPONS SYSTEM. ALTERNATE REFRIGERANTS MUST BE EMPLOYED IN A FASHION THAT MINIMIZES THE NEED FOR ALTERATION TO THIS HARDWARE, WHILE STILL MEETING DESIGN COOLING REQUIREMENTS. LEADING CANDIDATE REFRIGERANTS THAT HAVE LITTLE OR NO IMPACT ON ATMOSPHERIC OZONE INCLUDE HFC'S AND REFRIGERANT BLENDS OF HFC'S AND HCFC'S. THE PROPOSED PROJECT WILL EXAMINE THE SPECIFIC REQUIREMENTS OF EACH COOLING SYSTEM AND DETERMINE THE ALTERNATE REFRIGERANT THAT CAN BE EMPLOYED WITH MINIMAL HARDWARE CHANGE. SYSTEM MODIFICATIONS WILL BE IDENTIFIED THAT WILL ENSURE PROPER PERFORMANCE. TESTING OF THE REFRIGERANTS WILL BE UNDERTAKEN TO VERIFY THAT THE DESIGN APPROACH WILL PRODUCE THE DESIRED END RESULTS.