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Stephen Whitmore

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Mechanical and Aerospace Engineering

Faculty

Professor

Contact Information

Go toOffice Location: ENGR 419F
DialPhone: 435-797-2951
SendEmail: stephen.whitmore@usu.edu


Educational Background

PhD, Aerospace Engineering - Flight Dynamics and Control, (Applied Mathematics, Fluid Mechanics), University of California, Los Angeles, 1989
Formulation and Verification of a Technique For Compensation of Pneumati Attenuation Errors in Airborne Pressure Sensing Devices
Other, University of California, Los Angeles, 1987
MS, Mechanics and Structures, University of California, Los Angeles, 1983
Formulation and Implementation of a Practical Algorithm for Non-Stationary Adaptive State Estimation with Applications to Air Mass Reference Measurements
BS, Aerospace Engineering, University of Illinois, Urbana-Champaign, 1980


Biography

Dr. Whitmore joined USU in 2005 after more than 25 years as a civil servant for NASA. Prior to accepting early retirement from NASA, Dr. Whitmore served multiple roles within the agency including those of principal investigator, chief engineer, branch chief, and program manager. While at NASA he was fortunate to have worked on 7 different "X-planes." Dr. Whitmore is an Associate Fellow of the AIAA, and is a member of the AIAA Space Systems and Hybrid Propulsion Technical Committees. Dr. Whitmore is a strong advocate for the developing commercial space industry, and is a Member of the Commercial Space Flight Federation. Dr. Whitmore is a licensed private pilot with more than 400 hours as pilot in command and has accumulated numerous flight and flight-simulator hours as a flight test engineer in several military-class high performance jet aircraft.


Teaching Interests

Dr. Whitmore teaches upper division and graduate classes in fluid mechanics (MAE 5420 Compressible Fluids), propulsion systems (MAE 5540 Propulsion Systems, and MAE 6530, Advanced Propulsion Concepts), and instructs a section of the capstone senior design course (MAE 4800, 4810). His senior design teams have won the NASA-sponsored University Student Launch Initiative (USLI) Competition at Huntsville, AL, four times (2008, 2009, 2011, and 2012). Previously Dr. Whitmore instructed the junior level Instrumentation and measurements class (MAE 3340). Prior to his USU service Dr. Whitmore instructed courses in Space Systems (SS3011), and Astrodynamics (AE 4362), at the Naval Postgraduate School in Monterey, CA.

Research Interests

Since coming to USU, Dr. Whitmore has procured more than $2 million in research funding. His funding sources have included NASA, DoD, Federally Funded Research and Development Centers (FFRDC), the Utah Governor’s Economic Development Council (GOED), the Utah Science Technology and Research (USTAR) initiative, and Private Industry. Dr. Whitmore has published over 150 technical monographs including peer-reviewed journal articles, NASA-technical papers and technical memoranda, book chapters, and technical papers published in conference proceedings. He has been awarded 4 patents with 7 patent applications pending. *********************************************** GREEN PROPELLANTS .... ************************************************ Dr. Whitmore's current research focus is directed towards developing less hazardous, environmentally-friendly "green" propellant replacements for hydrazine. His research team recently developed a novel micro-hybrid gas generator that uses inexpensive and environmentally additively-printed thermoplastics as propellants. This alternative propellant technology derives from the electrical breakdown properties of certain 3-D printed thermoplastics like Acrylonitrile Butadiene Styrene (ABS), Low Density Polyethylene (LDPE) and High-Impact-Polystyrene (HIPS). These properties were discovered serendipitously while investigating the thermodynamic performance of ABS as a hybrid rocket fuel. When an electrostatic potential is placed across electrodes embedded into the 3-D printed material, charges flow from the energized electrode causing a localized electrostatic breakdown of the fuel material. This breakdown allows the charges to carve a path through the material. The resulting arc-track completes the circuit path to return electrode. Current flowing through the material causes Joule heating and pyrolyzes some of the material hydrocarbons. Ignition of the pyrolized fuel vapors occurs as soon as oxidizer flow is initiated. The arc-ignition concept has been engineered into a power-efficient system that can be started, stopped, and restarted with a high degree of reliability. On demand ignition has been demonstrated using compressed air, nitrous oxide (N2O), gaseous oxygen, and hydrogen peroxide as oxidizers. The arc ignition process is extremely energy efficient, requiring as little as 10 W for less than one second. Typical ignition energies are less than 10 Joules. The arc-ignition system has been demonstrated across a wide range ambient pressures including vacuum conditions. Recently, a small prototype system that burned ABS in enriched air (40% O2), was spaceflight tested at 170 km altitude. The payload was launched aboard a terrier Malemute launch vehicle from the NASA Wallops Flight Facility. The system successfully performed multiple restarts under hard-vacuum spaceflight conditions. Additive manufacturing is an essential feature of this technology. Multiple vendors using well-developed commercial technologies can produce identical pieces simultaneously, resulting in a "virtual assembly line." This approach is ideal for supporting the small-to-intermediate volume production rates required for most Aerospace applications, and offers potential of improving component quality, consistency, and performance, while reducing development and production costs. Dr. Whitmore and his team have recently received two key patents that are key to commercialization of this potentially market-disruptive technology. ******************************************************* FLUSH AIRDATA SENSING SYSTEM .... ****************************************************** Dr. Whitmore has also lead up the development of the new Flush Air Data System, known as FADS for the Sierra Nevada Corporation's Dream Chaser Reentry Vehicle. Dream Chaser is a multi-use spacecraft designed to glide back to Earth after re-entry, similar to the unpowered landings of the now-retired space shuttle. USU's role has been focused on algorithm development, sensor configuration optimization, sensor communication, aerodynamic calibration, redundancy management, systems verification & validation and flight test data analysis. Members of the USU team recently traveled to Edwards Air Force Base to support both the captive carry and free-flight tests at NASA’s Armstrong Flight Research Center. Accurate air speed information is critical for Dream Chaser to glide through the atmosphere on its approach to the runway. FADS generates air speed data using multiple flush-mounted sensors located on the nose of the spacecraft. By comparing air pressure values at multiple points, the autonomous Dream Chaser can calculate its air speed and adjust its flight path. The FADS represents an important milestone in reusable spacecraft design. The system eliminates the need for conventional air-data probes that extend from the side of a spacecraft. The probes used on the space shuttle, for example, were susceptible to the extreme temperatures of re-entry and were deployed only after the hottest phases of flight. On Nov. 11, SNC and NASA engineers tested the FADS by hoisting Dream Chaser 12,000 feet into the air via a Chinook helicopter and then cutting it loose, letting the vehicle fly unpowered, gliding toward Edwards Air Force Base where it gently touched down on runway 22-left. The successful free-flight test confirmed Dream Chaser’s FADS system worked correctly.

Awards

NASA MSFC Summer Faculty Research Fellowship, 2018

NASA

Researcher of the Year, 2017

USU MAE Department

NASA MSFC Summer Facuty Fellow Appointment, 2016

NASA Marshall SpaceFlight Center

Researcher of the Year, 2016

USU MAE Department

NASA MSFC Summer Facuty Fellow Appointment, 2015

NASA Marshall SpaceFlight Center

Best Technical Paper, 2012

Hybrid and Solid Propellant Technical Sessions

Winning Team, Faculty Mentor to Student Design Team NASA/ATK University Student Launch Initiative 2012, 2012

NASA Marshall Spaceflight Center

Winning Team, Faculty Mentor to Student Design Team NASA/ATK University Student Launch Initiative 2011 , 2011

NASA Marshall Spaceflight Center

Best Technical Paper, 2010

Ground Test Sessions, 43rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference

Utah Engineering Educator of the Year , 2009

Utah Engineering Council, Governor's Economic Council

Winning Team, Faculty Mentor to Student Design Team , 2009

NASA/ATK University Student Launch Initiative

Utah Aerospace Engineering Educator of the Year , 2008

Utah Section, AIAA

Winning Team, Faculty Mentor to Student Design Team, 2008

NASA/ATK University Student Launch Initiative

Associate Fellow Appointment , 2000

American Institute of Aeronautics and Astronautics

NASA Headquarters Achievement Award - Engineering Achievement Medal , 1997

NASA

NASA DFRC Honor Award - Outstanding Paper for Year 1996, 1996

NASA

NASA DFRC Honor Award - Outstanding Scientist for Year 1993, 1994

NASA

Excellence in Technical Presentation Award, Aerotech '91, 1991

Society of Automotive Engineers (SAE)

NASA ARC Honor Award - Outstanding Scientist for Year 1989, 1990

NASA

NASA Headquarters Honor Award - Group Engineering Achievement Award , 1984

NASA Headquarters

Publications - Abstracts

    Publications - Books & Book Chapters

      Book Chapters

    * Has not been peer reviewed

    Publications - Fact Sheets

      * Has not been peer reviewed

      Publications - Curriculum

        * Has not been peer reviewed

        Publications - Journal Articles

          Academic Journal

        • Whitmore, S.A, Walker, S.D, (2016). Engineering Model for Hybrid Fuel Regression Rate Amplification Using Helical Ports. Journal of Propulsion and Power, 32:6, 1674-1694. doi: http://dx.doi.org/10.2514/1.B36208
        • Whitmore, S.A, Merkley, S.L, Tonc, L., Mathias, S., (2016). Survey of Selected Additively Manufactured Propellants for Arc Ignition of Hybrid Rockets. Journal of Propulsion and Power, 32:6, 1494-1504. doi: http://dx.doi.org/10.2514/1.B36106
        • Whitmore, S.A, (2016). Additive Manufacturing as an Enabling Technology for "Green" Hybrid Spacecraft Propulsion. IEEE Xplore, Additive Manufacturing as an Enabling Technology for "Green" Hybrid Spacecraft Propulsion, 47:2, on-line artical. doi: 10.1109/RAST.2015.7208305
        • Whitmore, S.A, (2015). Additively Manufactured Acrylonitrile-Butadiene-Styrene–Nitrous-Oxide Hybrid Rocket Motor with Electrostatic Igniter. Journal of Propulsion and Power, AIAA, 31:4, 1217-1220. doi: 10.2514/1.B35595
        • Whitmore, S.A, Sobbi, M., Walker, S., High Regression Rate Hybrid Rocket Fuel Grains with Helical Port Structures . AIAA Journal of Propulsion and Power
        • Whitmore, S.A, Peterson, Z.W, Eilers, S.D, Talley, D., (2014). Deep Throttle of a Nitrous Oxide and HTPB Hybrid Rocket Motor. AIAA Journal of Propulsion and Power, 30:01, 78-86. doi: DOI: 10.2514/1.B34967
        • Whitmore, S.A, Peterson, Z.P, Gupta., A., (2014). Closed-Loop Precision Throttling of a Hybrid Rocket Motor. AIAA Journal of Propulsion and Power, 30:1, 325-336. doi: DOI: 10.2514/1.34924
        • Whitmore, S.A, Eilers, S.D, Merkley, D.P, Judson, M.I, Talley, J.R, (2013). Regeneratively Cooled Multiple-Use Plug Hybrid Motor Nanosatellites. AIAA Journal of Propulsion and Power, 29:6, 1420-1434.. doi: 10.2514/1.B3518
        • Whitmore, S.A, Peterson, Z., Eilers, S., (2013). Comparing Hydroxyl Terminated Polybutadiene and Acrylonitrile Butadiene Styrene as Hybrid Rocket Fuels," : AIAA Journal of Propulsion and Power, Vol. 29, No 3, May-June, 2013, pp. 582-592.. AIAA Journal of Propulsion and Power, 29:3, 582-592. doi: 10.2514/1.B324382
        • Whitmore, S.A, Durgesh, V., Naughton, J., Strike, J., (2013). Experimental Investigation of Base-Drag Reduction via Boundary-Layer Modification. AIAA Journal, 51:2, 416-425. doi: 10.2514/1.J051825
        • Whitmore, S.A, Merrill, R.S, Hess, R., (2012). Nonlinear Large Angle Solutions of the Blade Element Momentum Theory Propeller Equations. AIAA J. of Aircraft, 49:4, 321-328.
        • Whitmore, S.A, Eilers, S.D, Talley, J.R, (2012). Side Force Amplifcation on an Aerodynamically Thrust Vectored Aerospike Nozzle. AIAA Journal of Propulsion and Power, 48:4, 811-819.
        • Whitmore, S.A, Erni, N.M, Baker, D.J, Rathakrishnan, E., (2012). Closed-Loop Attitude Control Using Fluid Dynamic Vectoring on an Aerospike Nozzle. International review of Aerospace Engineering, 5:1, 8-20.
        • Whitmore, S.A, Kraus, K., (2011). Analytical and Experimental Evaluation of Aerodynamic Thrust Vectoring on an Aerospike Nozzle. J. Utah Academy of Arts, Letters and Sciences, 8:1
        • Whitmore, S.A, Wilson, M., Friedman, P., (2011). Wiener Deconvolution for Reconstruction of Pneumatically-Attenuated Pressure Signals . AIAA Journal , 49:5, 706-714.
        • Whitmore, S.A, Wilson, M., Eilers, S., (2010). A Novel Technique for Reconstructing High-Frequency Transient Rocket Chamber Pressure Measurements . AIAA Journal of Spacecraft and Rockets , 47:3, 427-441.
        • Whitmore, S.A, Smith , T., (2010). Interim Access to the International Space Station . AIAA Journal of Spacecraft and Rockets , 47:3, 503-520.
        • Whitmore, S.A, Fox, B., (2009). Improved, Accuracy, "Second order Response Model for Pressure Sensing Systems. AIAA Journal of Aircraft , 46:2
        • Whitmore, S.A, Smith , T., (2009). Launch and Development Analysis for a Small, MEO, Technology Demonstration Satellite . AIAA Journal of Spacecraft and Rockets , 46:2
        • Eilers, S.D, Whitmore, S.A, (2008). Correlation of Hybrid Rocket Propellant Regression Measurements with Enthalpy-Balance Model Predictions . AIAA Journal of Spacecraft and Rockets , 45:4, 1010-1020.
        • Whitmore, S.A, Bingham, B., Young, Q., (2008). Deployment of a High-Latitude Dynamic E-Field Pico-Satellite Sensor Constellation . International Review of Aerospace Engineering , 1:4, 560-567.
        • Whitmore, S.A, (2008). Engineering Model of Temperature-Induced Pressure Gradients in Pneumatic Sensors for rarefied Flow Conditions. AIAA Journal of Spacecraft and Rockets , 45:4, 760-765.
        • Whitmore, S.A, Eilers, S.D, (2008). A Single Amplifier Third Order Butterworth Filter for Aerospace Anti-aliasing Applications. International Review of Aerospace Engineering , 1:2, 251-257.
        • Whitmore, S.A, Anderson , B., (2008). Aerodynamic Lift Enhancement of a Lunar Return Capsule . International Review of Aerospace Engineering , 2:2, 112-122.
        • Whitmore, S.A, (2007). Design of a Passively Reefed, Collapsible Drough Parachute System . AIAA Journal of Aircraft , 44:6, 1822-1839.
        • Whitmore, S.A, (2007). Real Gas Extensions to the Tangent Wedge and Tangent Cone Analysis . AIAA Journal , 5:8
        • Whitmore, S.A, Ellsworth, J.C, (2007). Reentry Air Data System for a Sub-orbital Spacecraft Based on X-34 Design . AIAA Journal of Spacecraft and Rockets , 45:4, 716-732.
        • Whitmore, S.A, (2006). A Frequency Response Model for Branched Pneumatic Sensing Systems . AIAA Journal of Aircraft , 43:6, 1845-1853.
        • Whitmore, S.A, Naughton , J.W, Sprague , S., (2002). Blunt-Body Drag Reduction using Forebody Surface Roughness . AIAA Journal of Spacecraft and Rockets , 39:4, 596-604.
        • Whitmore, S.A, (2002). Frequency Response of Pressure Sensor Configurations in Slip-Flow Conditions . AIAA Journal of Spacecraft and Rockets , 39:2, 219-226.
        • Whitmore, S.A, Moes , T.R, (2000). Base-drag reduction experiments on the X-33 Linear Aerospike SR-71 Flight Program . AIAA Journal of Spacecraft and Rockets , 37:3, 297-303.
        • Rohloff, T.H, Whitmore, S.A, Catton, I., (1999). Fault-Tolerant Neural Network Algorithm for Flush Air Data Sensing . AIAA Journal of Aircraft , 36:3, 541-549.
        • Rohloff, T.J, Whitmore, S.A, Catton, I., (1998). Air Data Sensing from Surface Pressure Measurements using a Neural Network Method . AIAA Journal, 36:11, 2094-2110.
        • Whitmore, S.A, Davis , R.J, Fife, M.J, (1996). In-Flight Demonstration of a Real-Time Flush Air Data Sensing System . AIAA Journal of Aircraft , 33:5, 970-977.
        • Whitmore, S.A, Petersen, B.J, (1996). Dynamic Response of Pressure Sensing Systems in Slip-Flow with Temperature . AIAA Journal , 37:6, 772-774.
        • Whitmore, S.A, Moes, T.R, Larson, T.L, (1992). High Angle-of-Attack Flush Air Data Sensing System . AIAA Journal of Aircraft , 29:5, 915-919.
        • Whitmore, S.A, Leondes , C.T, (1991). Pneumatic Distortion Compensation for Aircraft Surface Pressure Sensing Devices . AIAA Journal of Aircraft , 28:12, 828-836.
        • Whitmore, S.A, Leondes , C.T, (1986). Formulation and Implementation of a Practical Algorithm for Non-Stationary Adaptive State Estimation . International Journal of Control , 44:3, 767-775.
        • Professional Journal

        • Whitmore, S.A, Inkley, N.R, Merkley, D.P, Judson, M.I, (2015). Development of a Power-Efficient, Restart-Capable Arc Ignitor for Hybrid Rockets. Journal of Propulsion and Power, AIAA, 31:6, 1739-1749. doi: 10.2514/1.B35681
        • Whitmore, S.A, Walker, S.D, Merkley, D.P, Sobbi, M., (2015). High Regression Rate Hybrid Rocket Fuel Grains with Helical Port Structures. Journal of Propulsion and Power, AIAA, 31:6, 1727-1738. . doi: 10.2514/1.B35615
        • Whitmore, S.A, Wilson, J.R, Ritter, M.A, Williams, L.T, (2015). Estimating the Enthalpy of Gasification of Acrylonitrile–Butadiene–Styrene Hybrid Rocket Fuels. Journal of Propulsion and Power, AIAA, 31:4, 1033-1049. doi: 10.2514/1.B35621
        • Whitmore, S.A, Talley, D., Electrostatic Ignitor for an Additively Manufactured ABS-Nitrous Oxide Hybrid Rocket Motor. AIAA J. or Propulsion and Power.
        • Whitmore, S.A, Bath, A.R, Rathakrishnan, E., (2011). Sounding Rocket Energy Management Using Cold-Gas Aerospike Thrusters: A Senior Capstone Design Course. International Review of Aerospace Engineering, 4:4, 79-96.

        * Has not been peer reviewed

        Publications - Literary Journal

          * Has not been peer reviewed

          Publications - MultiMedia

            * Has not been peer reviewed

            Publications - Technical Reports

              Research Reports

            * Has not been peer reviewed

            Publications - Translations & Transcripts

              Publications - Other

                * Has not been peer reviewed

                Scheduled Teaching

                MAE 5540 - Propulsion Systems, Spring 2018

                MAE 5420 - Compressible Fluid Flow, Fall 2017

                MAE 6530 - Propulsion Systems, Fall 2017

                MAE 5540 - Propulsion Systems, Spring 2017

                MAE 6530 - Propulsion Systems, Spring 2017

                MAE 5420 - Compressible Fluid Flow, Fall 2016

                MAE 6530 - Propulsion Systems, Fall 2016

                MAE 3340 - Instrumentation and Measurements, Spring 2016

                MAE 5540 - Propulsion Systems, Spring 2016

                MAE 5420 - Compressible Fluid Flow, Fall 2015

                MAE 6530 - Propulsion Systems, Summer 2015

                MAE 3340 - Instrumentation and Measurements, Spring 2015

                MAE 5540 - Propulsion Systems, Spring 2015

                MAE 5420 - Compressible Fluid Flow, Fall 2014

                MAE 6530 - Propulsion Systems, Summer 2014

                MAE 3340 - Instrumentation and Measurements, Spring 2014

                MAE 5540 - Propulsion Systems, Spring 2014

                MAE 5420 - Compressible Fluid Flow, Fall 2013

                MAE 6530 - Propulsion Systems, Summer 2012

                MAE 4810 - Capstone Design II, Spring 2012

                MAE 5540 - Propulsion Systems, Spring 2012

                MAE 5420 - Compressible Fluid Flow, Fall 2011

                MAE 5930 - Special Problems, Fall 2011

                MAE 6530 - Propulsion Systems, Summer 2011

                MAE 4810 - CAPSTONE DESIGN II, Spring 2011

                MAE 5540 - PROPULSION SYSTEMS, Spring 2011

                MAE 5540 - PROPULSION SYSTEMS, Spring 2011

                MAE 5420 - Compressible Fluid Flow, Fall 2010

                MAE 5930 - Special Problems, Fall 2010


                Extension

                MAE Online Aerospace Masters Degree Program, 2010 - 2014

                Graduate Students Mentored

                David Brewer, Mechanical & Aerospace Engineering, August 2016 - December 2016
                Isaac Armstrong, Mechanical & Aerospace Engineering, August 2016 - December 2016
                Joel Marshall, Mechanical & Aerospace Engineering, May 2016 - December 2016
                Spencer Mathias, Mechanical & Aerospace Engineering, May 2016 - December 2016
                Zachary Lewis, Mechanical & Aerospace Engineering, May 2016 - December 2016
                Lan Liu, Mechanical & Aerospace Engineering, January 2016 - December 2016
                Stehen Merkley, Mechanical & Aerospace Engineering, August 2014 - December 2016
                Daniel Merkley, Mechanical & Aerospace Engineering, June 2012 - December 2016
                Britany Chamberlain, Mechanical & Aerospace Engineering, September 2011 - December 2016
                Zee Spurrier, Mechanical & Aerospace Engineering, December 2013 - August 2016
                Sean Walker, Mechanical & Aerospace Engineering, September 2013 - December 2015
                Zee Spurrier, Mechanical & Aerospace Engineering, December 2013 - August 2015
                Daniel Merkley, Mechanical & Aerospace Engineering, June 2012 - December 2014
                MIchael Judson, Mechanical & Aerospace Engineering, January 2011 - May 2014
                Mansour Sobbi, Mechanical & Aerospace Engineering, August 2013 - May 2014
                Nathan Inkley, Mechanical & Aerospace Engineering, November 2012 - December 2013
                James Wilson, Mechanical & Aerospace Engineering, September 2011 - December 2013
                MIchael Judson, Mechanical & Aerospace Engineering, January 2011 - December 2013
                Weston Nelson, Mechanical & Aerospace Engineering, November 2011 - July 2013
                Shannon Eilers, Mechanical & Aerospace Engineering, August 2007 - July 2013
                John McCulley, Mechanical & Aerospace Engineering, August 2010 - May 2013
                Matthew Wilson, Mechanical & Aerospace Engineering, August 2009 - May 2013
                Jason Firth, Mechanical & Aerospace Engineering, October 2011 - December 2012
                Andrew Bath, Mechanical & Aerospace Engineering, August 2010 - December 2012
                Zach Peterson, Mechanical & Aerospace Engineering, January 2010 - December 2012
                Sarah Isert, Mechanical & Aerospace Engineering, November 2010 - May 2012
                Ryan Schaeffermeyer, Mechanical & Aerospace Engineering, January 2010 - December 2011
                Brian Solomon, Mechanical & Aerospace Engineering, January 2011 - December 2011
                Rob Merrill, Mechanical & Aerospace Engineering, September 2010 - September 2011
                Spencer Sessions, Mechanical & Aerospace Engineering, September 2010 - February 2011