DISPOSABLE-TETHER PAYLOAD DEPLOYMENT SYSTEM

THIS PROJECT ANALYZES A NOVEL USE OF A SHUTTLE-BASED TETHER SYSTEM TO RELEASE A PAYLOAD INTO ORBIT WITH MORE ENERGY THANTHE SHUTTLE OR TO CAUSE CONTROLLED REENTRY OF AN EXTERNAL TANK. COMPARED TO CONCEPTS ANALYZED TO DATE, THIS CONCEPT RADICALLY REDUCES THE SYSTEM MASS AND VOLUME AND THE TIME REQUIRED FOR TETHER OPERATIONS BY USING LOW-TENSION DEPLOYMENT AND DISPOSABLE TETHERS. LOW DEPLOYMENT TENSION CAUSES NEAR-HORIZONTAL DEPLOYMENT FOLLOWED BY A PENDULUM SWING THROUGH THE VERTICAL. AFTER PAYLOAD RELEASE, THE TETHER IS ITSELF RELEASED. ELIMINATING RETRIEVAL (AND THE ASSOCIATED MOTORS, BATTERIES, ETC.) SIMPLIFIES THE DEPLOYERAND MAY ALLOW IT TO TRAVEL AS A "HITCH-HIKER". PHASE I WORKPURSUES SIX AREAS OF CONCEPT FEASIBILITY: (1) CONTROL STRATEGIES FOR PRECISE DEPLOYMENT AND RELEASE, (2) CHARACTERIZATION OF OPERATIONAL IMPACTS AND CONSTRAINTS, (3) INITIAL ANALYSES OF SYSTEM FAILURE MODES AND SAFETY ISSUES, (4) FEASIBILITY ANALYSES OF PROMISING EARLY APPLICATIONS, (5) IDENTIFICATION OF PAYLOAD BAY LOCATIONS FOR THE DEPLOYER, AND (6) FABRICATION, TESTING, AND ANALYSISOF A SPECIFIC DEPLOYER CONCEPT.