A BARREL BALLOON CAMPAIGN TO STUDY ENERGETIC ELECTRON PRECIPITATIONTHIS PROPOSAL DESCRIBES A BARREL (BALLOON ARRAY FOR RADIATION RELATIVISTIC ELECTRON LOSSES) BALLOON CAMPAIGN TO STUDY ELECTRON PRECIPITATION. THE PROPOSED WORK ADDRESSES ONE OF THE THREE PRIORITIZED SCIENCE GOALS FROM THE VAN ALLEN PROBES EXTENDED MISSION PROPOSAL TO INVESTIGATE"THE RELATIVE IMPORTANCE OF PRECIPITATION AND MAGNETOPAUSE LOSSES OF ENERGETIC PARTICLES IN THE INNER MAGNETOSPHERE AND PROVIDE MORE DEFINITIVE INFORMATION ABOUT THE CAUSES AND CONSEQUENCES OF THE PRECIPITATION". THE BARREL TEAM HAS SO FAR CONDUCTED THREE SUCCESSFUL BALLOON CAMPAIGNS. THE PROPOSED CAMPAIGN WILL STUDY WAVE-PARTICLE INTERACTIONS THAT CAUSE PRECIPITATION AND INVESTIGATE THE RELATIVE IMPORTANCE OF DIFFERENT PLASMA WAVES IN CAUSING PARTICLE LOSS. TO ACHIEVE THE SCIENCE OBJECTIVES OUTLINED BELOW WE WILL LAUNCH UP TO 8 BALLOON PAYLOADS FROM KIRUNA SWEDEN DURING AUGUST 2016. THE PAYLOADS ARE ALREADY BUILT HAVING BEEN REFURBISHED AFTER FLIGHTS FROM SWEDEN DURING A SIMILAR CAMPAIGN LAST YEAR. LIKE OTHER LOW-ALTITUDE MEASUREMENTS BALLOONS PROVIDE AN ESSENTIAL TOOL FOR MONITORING AND STUDYING PRECIPITATION THUS COMPLEMENTING THE EQUATORIAL VAN ALLEN PROBE MEASUREMENTS.