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19760011102.Pdf XR-75-391 Contract 954205 MARS SURFACE SAMPLE RETURN TRADEOFF STUDIES Final Report October 1975 Approved Technical Director This report was performed for the Jet Propulsion Laboratory, California Institute of Technology, sponsored by the National Aeronautics and Space Administration under Contract NAS7-100. MARTIN MARIETTA CCRPORATION DENVER DIVISION Denver, Colorado 80201 Ihis report docllr~_ntsthe results of four specific study tasks defined by the JPL seady manager as critical to the evolving understanding of the lhrs Surface Sample Beturn (LISSR) mission. Task 1 campares the Mars mission opportunities in 1981, 1983184, 1986, 1988, and 1990 to detennine which mission modes are possible and appropriate for each. Task 2 mines the design features of the hardware systems used to return the saaple, in the Mars orbit rendezvous mode, to identify ways in which the probability of back contamination can be minimized. Task 3 loolcs into the hardware and performance trade offs between the options of direct entry of the returning sample capsule at Earth and the orbital capture of that capsule for recovery by the Shuttle. Task 4 explores the possibilities for increasing the landed weight at Mars, beyond that possible with zfnimally modified Viking lander, to support HSSR missi-n modes involvk-g heavier systems. Bode technical mesroranda were prepared in accordance with the Contract Schedule, Article 1, Paragraph a. (31, of JPL Contract No. 954205, Mars Surface Sample Return (lSSR) Tradeoff Studies. A technical memorandum is submitted for each of the four tasks in the Statement of Work as follows: Task 1: Compile mission performance data for the leading mission mode candidates for the 1981, 1984, 1986, 1988 and 1990 opportunities. Single and dual shuttle launches, in-orbit weights, landed weights, Earth return weights, and AV budgets shall be coasidered. Titan 111EICentaur launches are included for comparison purposes only, but not emphasized. Task 2: Identify and describe back contamination control options that could be incorporated into the Mars Ascent Vehicle (MAV) rendez- vous and docking, docking and sample transfer scheme, orbiter, Earth Return Vehicle (ERV) and Earth recovery hardware and operational sequences. Task 3: Perform tradeoffs for preliminary performance and hardware defi- nitions to compare the direct entry and orbital capture modes for Earth recovery. Task 4: Define and quantify available options for increasing landed weight. Appendices A through B are technical notes completed during the course of this work that provide additional detail and substantiation for assump- tions made in performing the contract trades. Martin Marietta wishes to recognize the contributions of the following individuals to this study : Louis D. Friedman of the Jet Propulsion Laboratory, Technical Representative of the Contracting Officer, for management and direction. Arthur L. Satin - Mission Analysis Norm Phillips - Back Contamination Design Considerations and Illustrations Scott K. Asnin - Mission Analysis TABLE OF CONTENTS Page Abstract ii Foreword iii Acknowledgement iv Table of Contents v List of Figures vii List of Tables ix Glossary xii List of Symbols riii I INTRODUCTION I1 TASK 1 MISSION PERFORMANCE DATA FOR VARIOUS MARS SAMPLE RETURN MODES A. INTRODUCTION B. APPROACH C. MISSION MODE DESCRIPTION D . EARTH-MARS PERFORMANCE SUMMARY E. MARS-EARTH PWFCRMANCE SUMMARY F . ROUNDTRIP MISSION OPP(IRTUiU'IrlIES MOR SUMMARY DIRECT RETURN SUMMARY G. TASK 1 - CONCLUSIONS I11 TASK 2 BACK CONTAMINATION CONTROL OPTIONS A. EVENT #1 (DURING TIME SPENT ON THE SURFACE OF MARS) B. EVENT #2 (SAMPLE TRANSFER FROM MAV TO ERV) C. EVENT 113 (SAMPLE RETRIEVAL AT EARTH) D. ALTERNATIVE DOCKING COKFIGURATION LIST OF FIGURES IUS/Tug Performance Potential Contamination Sources and Preventive Measures Back Contamination Prevention Concepts Canister Sealing Sequence Using Plastic Liner Alternative Docking Concept Based on Apollo Type Pr~be/DrogueDesign Sample Recovery in Earth Orbit Alternative Docking Concept Based on Apollo Type ProbeIDrogue Design IV- 1 Earth Orbiting Capsule and Earth Entry Capsule Configurations Influence of Entry Angle on Allowable Parachute Deployment Altitude Variation of Propellant Weight, Aeroshell Weight and Landed Weight with Entry Angle for Fixed Entry Weight Variation in Landed Weight and Entry Weight Constraints with Entry Angle Altitude for Parachute Deployment as Influenced by LID Influence of Smaller Corridor, Higher LID and Higher Thrust on Landed Weight Improvement in Landed Mass and Relaxation of Entry Mass ,onstraints is Made Posr Lble by Adjustment of EntryIDescent Parameters Non-Propulsive Mass of Interplanetary Cruise Vehicle (Included 28 Kg for Earth Entry Capsule) Deorbit AV for the 5-day Orbit Chute Deployment Attitude for the 5-Day Orbit Figure Page D-3 Lander Descent Engine Propellant Requirements D-8 D-4 Landed Weight for the 5-day Orbit D-9 E- 1 Minimum Deployment Attitude E-3 E-2 Maximum Dynamic Pressure E-3 E- 3 Propellant Requirements E-4 E-4 Landed Dry Weight E-5 ?aIST OF TABLES -Table Page 11- 1 Ehrth-Mars Performance Summary: 11-8 198112 Launch Year; L/V = Titan 3ElCentaur Earth-Mars Performance Summary: 198314 Launch Year; L/V = Titan 3ElCentaur Earth-Mars Performance Summary: 1986 Launch Year; L/v = Titan 3ElCentaur Ear th-Mars Performance Sunnnary : 1988 Launch Year; LIV = Titan 3ElCentaur Earth-Mars Performance Sumnary: 1990 Launch Year; t/V = Titan 3ElCentaur Ear th-Mar s Perf ormanse Summary : 198112 Launch Year; L/V = ShuttleIIUS Earth-Mars Performance Summary : 198314 Launch Year; L/V = ShuttleIIUS Earth-Mars Performance Summary : 1986 Launch Year; L/V = ShuttlelIUS Earth-Mars Performance Summary: 1988 Launch Year, L/V = Shuttle/IUS Earth-MaT:s Performance Summary: 1990 La-~nchYear; LIV = ShuttleIIUS Earth-Mars Performance Summary : 1'3112 Launch Year; L/V = ShurtleITug Earth-Mars Performance Summary: 198314 Launch Year; LIV = Shuttl-e/Tug Earth-Mars Performance Summary : 198516 Launch Year; L/V = Shuttle/Tug Ear th-Mars Performance Summary : IT- 15 I988 Launch Year; ilV = ShuttleITug Ear th-Mars Performance Summary : 11-15 1990 Launch Year; L/J = Shuttle/Tug -Table Page 11- 16 Maximum Available ERV Weight for Return to Earth 11- 16 Potential Earth Return Windows Minimum Energy Retvrn-to-Earth Sample EMERGE Output, MOR Type 11, 1988, L/V = Shuttle/Tug Minimvm Time Missions Sample EMERGE Output, MOR Type 11, 1988, L/V = Shuttle/Tug Maximum ERV Weight Margin Miss ions Dual Launch, Out-of-Orbit, MOR Single Launch, Direct Entry, MOR Single Launch, Out-of-Orbit, MOR Summary of Direct Return Mission ERV Weight Margins* with Minimum Energy Mars-Earth Transfers IV- 1 Comparison of Mass Breakdown for Earth Orbiting and Entry Capsules Dual Launch, Out-of -Orbit, MOR: Minimum Mission Time Dual Launch, Out-of-Orbit, MOR: Max ERV Weight ivIargin Single Launch, Out-of-Orbit, MOR: Minimum Mission Time Single Launch, Out-of-Orbit, MOR: Max l?RV We igb t Margin Single Launch, Direct Entry, MOR: Minimum Mission Time Single Launch, Direct Entry, MOR: Max ERV Weight Margin Pioneer Venus based ERV f!ass Breakdown JPL/LRC ERV Mass Breakdown ERV Sizing for 1981 and 1983184 Page C-2 MSSR Performance for Out-of-Orbit, Dual, I-aunch C-4 D-1 Performance Sumary for 5- lay 3nding Orbit, D-6 with Ve = 15650 fps and Aye = 4 , % = 0 ACS Attitude Control System EEC Earth Entry Capsule ERV Earth Return Vehicle IUS Interim Upper Stage LID Lift-to-Drag Ratio LD/ED Launch Date/Encount+r Date L/V Launch Vehicle M Mach Number 14Av Mars Ascent 7ehicle Wc Midcourse MOI Mars Orbital Injection I!OR Mars Orbital Rendezvous MSSR Mars Surface Sample Return PI I Propellar.; Inerts P/L Payload q Dynamic Yreasure RCS Reaction Control System VIS Yideo Imagtng System WNS Mission Number LIST OF SlXBOLS Energy C3 Earth Depxture DIA Declination of Launch Azimuth Per iapsis Altitude ,lerraia Height Specific Impulse Hyperbolic Excess Velocity v~ Entry Velocity Ent.-y Weight ERV Weight 'ERV WIN^ Insertion Weight W Liftoff Weight LIFT Landing Weight 'LND Landed k'eight 'LD Propellant Weight Flight Path Angle Entry Flight Path Angle Delta-V Earth Orbital Entry AV Mars Orbital Injection AV Statistical AV Trans-Earth Injection AV Entry Corridor 'Ihe krs Surface Sample Beturn (HSSR) mm.ision has been recognized by USA mission strategists and planetary scientists alike as the most attract- ive and potentially valuable unmanned firs exploration mission. The mission has been studied by a a.am'ber of groups in recent years (References 1 and 2 are mlesof previous work). Several problems and challenges merged from previous examinations of the mission that prompted Dr. Louis Friedman, flystudy manager for this contract, to request the four study tasks reported here. The first of these is that the projected cost of an MSSR mission makes it very di tcult to fit the program ;nto the NASA new start plan. There- fore, it appeared advisable to examit,r all the mission opportunities in the 1980-1990 time period to see if there Fere launch years offering more po- tential than othels. This information could then be factored into the dssicn planning process. Task 1 of this study is aimed at this objective. Task 1 also defines and examines the mission modes that are made possible by and are compatible with the Shuttle-IUS and Shuttle-Tug launch systems. Another problem encountered in planning the MSSRmission is minimizing the probability of bringing Mars organisms back into the Earth biosphere in an uncontrolled condition. T~SK2 of this study addresses the hardware design and operation features that could be incorporated into Mars Ascent Vehicle <MAV), the Earth Return Vehicle (ERV) and the hardware and sequences used in rendezvous and docking and recovery at Earth, to minimize back- contaminat ion probabilities . Task 3 derives also from the concerns over back contamin-tion. It compares the hardware implementation requirements for two methods of re- covering the sample capsule at Earth. One approach is to allow the capsule to enter the Earth's atmosphere directly from the Mars to Earth trajectory as ras done with the Apollo returns from the Moon.
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