1. International Planetary Probe Workshop 10
Entry, Descent, and Landing Systems Short Course Subject: Supersonic Retropropulsion Author: Karl Edquist NASA Langley Research Center
sponsored by
International Planetary Probe Workshop 10
June 15-16, 2013
San Jose, California

2. International Planetary Probe Workshop 10 Short Course 2013
Outline
Introduction
Recent Work
Recommended Next Steps
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

3. International Planetary Probe Workshop 10 Short Course 2013
Introduction
MSL EDL
Mars EDL with SRP
(NASA/TM )
Problem: Mars EDL technologies are nearing their payload limit
Mars Science Laboratory = 4.5 m aeroshell m parachute = 0.9 t payload
Larger supersonic parachutes are inhibited by scaling challenges
Goals beyond MSL:
More mass (10s of t)
Better accuracy (meters)
Higher landing elevation
Solution: Use propulsive deceleration = Supersonic Retropropulsion (SRP)
SRP is considered to be enabling for human-scale (5-40 t) & enhancing for robotic-scale (2-5 t) Mars EDL
1.8 MN O/CH4
3-4 Earth g’s
0.9 t payload
“As Mars missions approach human class entry masses, the required size of supersonic deployable aerodynamic decelerators renders them impractical…initiation of propulsive deceleration must occur earlier in the descent phase…SRP becomes an enabling technology for human class Mars missions.”
- NASA EDL Roadmap (TA09), November 2010.
40 t payload
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

4. SRP Early Developments
Wind tunnel tests from 1950s to 1970s studied SRP as an augmentation to aerodynamic deceleration
General aerodynamic trends were observed, but no development beyond the laboratory
CD,Total = CD,Aero + CT
CT (= T/q∞Sref) known from engine thrust and trajectory conditions
CD,Aero depends on vehicle geometry, jet configuration & thrust magnitude
Jarvinen, NASA CR NAS 7-576, 1970
Long period of inactivity from 1970s to 2000s
1 Jet, High Thrust
3 Jets, Low Thrust
Mach > 1
Jet
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

5. International Planetary Probe Workshop 10 Short Course 2013
SRP in EDL Project ( )
Wind Tunnel Testing
Mach 1.8 to 4.6
Cold gas jets
CT = T/(q∞Sref) = 0 to ~10
Surface pressure & high-speed video
LaRC 4x4
ARC 9x7
CFD Modeling
CFD complicated by unsteady & turbulent flow
Promising qualitative (flowfield structure) & quantitative (pressure) comparisons to wind tunnel data
DPLR
FUN3D
OVERFLOW
Mach 4.6, CT = 2
Flight Test Conceptual Design
Sounding rocket platform
Engine options, notional mass & packaging
Open Issues
Vehicle configurations, engine development, aerodynamic stability, aerothermodynamics, vehicle transitions, ground interactions, flight tests
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

6. NASA LaRC UPWT Test, Mach 4.6, AoA = 0
No Jets
1 Jet, CT = 2
3 Jets, CT = 2
4 Jets, CT = 2
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

7. CFD of NASA LaRC UPWT Test 3 Jets, Mach 4.6, AoA = 12, CT = 3
DPLR
OVERFLOW
FUN3D
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

8. SRP Recommended Next Steps
Define reference vehicles (robotic & human)
Allows sizing of propulsion system (engines, tanks, etc.)
Complete hot-fire engine tests
Provides data for startup transients & effect on vehicle aerodynamics
Develop large (100s of kN) throttle-able engines
Required for engine use through touchdown
Complete Earth-based & Mars precursor flight tests at progressively higher scale & complexity
Reduces risks for mission infusion
Eventually includes vehicle transitions & touchdown
Develop high-fidelity EDL simulations
SRP mass, packaging & performance
CFD-based aerosciences tools
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013

9. International Planetary Probe Workshop 10 Short Course 2013
References
Adler, M., Wright, M., Campbell, C., Clark, I., Engelund, W., and Manning, R. M., “DRAFT Entry, Descent, and Landing Roadmap, Technology Area 09," National Aeronautics and Space Administration, November 2010.
Dwyer-Cianciolo, A., et al, “Entry, Descent and Landing Systems Analysis Study: Phase 1 Report,” NASA/TM , July 2010.
Dwyer-Cianciolo, A., et al, “Entry, Descent and Landing Systems Analysis Study: Phase 2 Report on Exploration Feed Forward Systems,” NASA/TM , February 2011.
Korzun, A., “Aerodynamic and Performance Characterization of Supersonic Retropropulsion for Application to Planetary Entry and Descent,” Ph. D. Dissertation, Department of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA, 2012.
Edquist, K., et al, “Development of Supersonic Retro-Propulsion for Future Mars Entry, Descent, and Landing Systems,” AIAA Paper , AIAA Fluid Dynamics Conference, Chicago, IL, 28 June-2 July 2010.
Berry, S., et al, “Supersonic Retro-Propulsion Experimental Design for Computational Fluid Dynamics Model Validation,” IEEEAC Paper 1499, IEEE Aerospace Conference, Big Sky, MT, 5-12 March 2011.
Berry, S., Rhode, M., Edquist, K., and Player, C., “Supersonic Retropropulsion Experimental Results from the NASA Langley Unitary Plan Wind Tunnel,” AIAA Paper , AIAA Thermophysics Conference, Honolulu, HI, June 2011.
Berry, S., Rhode, M., and Edquist, K., “Supersonic Retropropulsion Experimental Results from the NASA Ames 9- x 7-Foot Supersonic Wind Tunnel,” AIAA Paper , AIAA Fluid Dynamics Conference, New Orleans, LA, June 2012.
Rhode, M., and Oberkampf, W., “Estimation of Uncertainties for a Supersonic Retro-Propulsion Model Validation Experiment in a Wind Tunnel,” AIAA Paper , AIAA Fluid Dynamics Conference, New Orleans, LA, June 2012.
Trumble, K., Schauerhamer, D., Kleb, B., and Edquist, K., “Analysis of Navier-Stokes Codes Applied to Supersonic Retro-Propulsion Wind Tunnel Test,” IEEEAC Paper 1471, IEEE Aerospace Conference, Big Sky, MT, 5-12 March 2011.
Trumble, K. et al, “An Initial Assessment of Navier-Stokes Codes Applied to Supersonic Retro-Propulsion,” AIAA Paper , AIAA Fluid Dynamics Conference, Chicago, IL, 28 June-2 July 2010.
Kleb, B., et al “Toward Supersonic Retropropulsion CFD Validation,” AIAA Paper , AIAA Thermophysics Conference, Honolulu, HI, June 2011.
Schauerhamer, D., et al, ”Continuing Validation of Computational Fluid Dynamics for Supersonic Retropropulsion,” AIAA Paper , AIAA Aerospace Science Meeting & Exhibit, Orlando, FL, 9-13 January 2012.
Zarchi, K., Schauerhamer, D., Kleb, B., Carlson, J. R., and Edquist, K., “Computational Fluid Dynamics Validation and Post-Test Analysis of Supersonic Retropropulsion in the Ames 9×7 Unitary Tunnel,” AIAA Paper , AIAA Fluid Dynamics Conference, New Orleans, LA, June 2012.
Post, E., Dupzyk, I., Korzun, A., Dyakonov, A., Tanimoto, R., and Edquist, K., “Supersonic Retropropulsion Flight Test Concepts,” 8th International Planetary Probe Workshop, Portsmouth, VA, 6-10 June 2011.
June 15-16, 2013
International Planetary Probe Workshop 10 Short Course 2013