REDUCED WEIGHT GONDOLAS FOR STRATOSPHERIC BALLOONS

STRATOSPHERIC AND RESEARCH BALLOONS CARRYING SCIENTIFIC INSTRUMENTS INTO THE UPPER ATMOSPHERE ARE VERY SENSITIVE TO PAYLOAD WEIGHT. REDUCTIONS IN BALLOON GONDOLA WEIGHT WILL ALLOW A CORRESPONDING REDUCTION IN BALLOON VOLUME REQUIRED TO REACH A GIVEN ALTITUDE RESULTING IN INCREASED SYSTEM RELIABILITY FOR A GIVEN FLIGHT. ALTHOUGH GONDOLA REQUIREMENTS VARY WITH TYPE OF INSTRUMENT PACKAGE, CURRENT GONDOLAS ARE OFTEN OPEN FRAME STRUCTURES OF ALUMINUM WITH SANDWICH PANEL PLATFORMS TO SUPPORT THE INSTRUMENT AND TELEMETRY PACKAGES. ADVANCED COMPOSITE MATERIALS WITH THEIRHIGH SPECIFIC STIFFNESS/STRENGTH OFFER AN OPPORTUNITY TO SIGNIFICANTLY REDUCE GONDOLA WEIGHT. THE GREATEST BENEFIT IS DERIVED BY DEVELOPING CONCEPTS AND DESIGN APPROACHES WHICH ARE TAILORED FOR COMPOSITE MATERIALS TO TAKE FULL ADVANTAGE OF THEIR HIGH SPECIFIC PROPERTIES WHILE ALLOWING FOR THE UNIQUE DESIGNS NECESSARY AT JOINTS LOAD INTRODUCTION POINTS. THE PROPOSED PHASE I PROGRAM DEVELOPS TWO COMPOSITE CONCEPTSFOR A LIGHTWEIGHT BALLOON GONDOLA. THE FIRST IS SIMILAR IN GEOMETRY TO EXISTING OPEN FRAME GONDOLAS WHILE THE SECOND CHANGES THE CONFIGURATION TO FURTHER REDUCE WEIGHT. BOTH CONCEPTS WILL BE ANALYZED AND DEVELOPED IN PHASE I TO OBTAINDETAILED DESIGNS. WITH INPUT FROM USER SCIENTISTS AND NASA,FOSTER-MILLER, INC. WILL SELECT A BASELINE COMPOSITE PROTOTYPE DESIGN. A CRITICAL COMPONENT OR JOINT FROM THIS DESIGN WILL BE FABRICATED AND TESTED TO OPTIMIZE THE DESIGN OF THE MATERIAL AS WELL AS THE GEOMETRY OF THE COMPONENT. PROTOTYPE GONDOLA PARTS WILL BE DEFINED IN DETAIL AND FABRICATION METHODS ESTABLISHED SUCH THAT A PROTOTYPE CAN BEFABRICATED, PROOF TESTED AND FLIGHT TESTED IN THE PHASE II PROGRAM.