September—Pasadena philanthropist Amos Throop (1811–1894) rents the Wooster Block building in Pasadena for the purpose of establishing Throop University, the forerunner of Caltech. In November of that year, Throop University opened its doors to 31 students and a six-member faculty.
Astronomer George Ellery Hale (1868–1938) arrives in Pasadena. He is the first Director of the Mount Wilson observatory. Hale becomes a member of Throop's board of trustees in 1907; under Hale's leadership, the transformation of Throop begins. December 17, 1903—Wright Brothers' first powered flight at Kitty Hawk, North Carolina. The Wrights pioneered many of the basic tenets and techniques of modern aeronautical engineering, such as the use of a wind tunnel and flight testing as design tools.
December 17, 1903—Wright Brothers first powered flight at Kitty Hawk, North Carolina. The Wrights pioneered many of the basic tenets and techniques of modern aeronautical engineering, such as the use of a wind tunnel and flight testing as design tools. (Pictured at left: W.Wright and A. Merrill, 1910.)
Harry Bateman (1882–1946) Professor of Mathematics, Physics, and Aeronautics, 1917–1946. One of the two first faculty members in Aeronautics, he was already an accomplished mathematical physicist when Hale recruited him. Bateman taught and carried out research in hydrodynamics, elasticity, and mathematical methods; authored four textbooks. His shoe boxes full of notes on special functions kept several mathematicians busy after his death on the "Bateman Manuscript Project," editing his notes into three classic volumes entitled Higher Transcendental Functions. Hale solicits donation and trustees approve construction for the first wind tunnel (4 by 4 foot) built in southern California.
Bateman, Harry (1953) Higher Transcendental Functions [Volumes I-III]. Vol.I-III. McGraw-Hill Book Company, New York.
Bateman, Harry (1954) Tables of Integral Transforms [Volumes I & II]. Vol.I & II. McGraw-Hill Book Company, New York. ISBN 07-019549-8
Albert A. Merrill (1875–1952) Instructor in Aeronautics, 1918–1930, 1940–1952. First Instructor in Aeronautics at Caltech. In 1895, the Boston Aeronautical Society was formed with Merrill, William H. Pickering, and James Means forming the executive committee. In 1911, he learned to fly, first at Squantum and later at the Wrights' place in Dayton. At Caltech, Merrill operated the first wind tunnel and complemented Bateman's theoretical instruction with wind tunnel measurement practice and airplane design. He was self-taught, holding several patents and building several airplanes, including the "Dill Pickle" with Klein and Millikan.
Donald Douglas starts his aircraft company in Santa Monica.
Hale is joined by chemist Arthur A. Noyes (1866–1936) and physicist Robert A. Millikan (1868–1953). These three men set the school, which by then had been renamed the California Institute of Technology, firmly on its new course. Millikan serves as Chairman (effectively the President) until 1945.
Daniel Guggenheim sets up $2.5 million fund to jumpstart seven aeronautical schools in seven universities, including Caltech. A sum of $300,000 is earmarked for Caltech for the construction of a laboratory and the establishment of a graduate school in aeronautics. (Pictured at left: Guggenheim building under construction, 1927.)
Arthur Emmons Raymond (1899–1999). Assistant Professor of Aeronautics, 1927–1934. Chief Engineer, Douglas Aircraft Company (1925–60). Raymond works for Douglas during the week and begins teaching a Saturday class on airplane design to von Kármán, Klein, Bateman, Clark Millikan, Sechler, and Merrill; serves as longtime GALCIT connection to Douglas Aircraft for testing of DC-1 through DC-8 aircraft. Becomes VP of Douglas Aircraft.
Charles Lindbergh completes first solo flight across the Atlantic Ocean in May; Roosevelt Field near New York City to Paris in 33.5 hours.
Birth of GALCIT through the Daniel Guggenheim Fund for the Promotion of Aeronautics. From 1926–1928, the Guggenheim Laboratory was built, wrapping itself around the 10-foot wind tunnel. The academic staff consisted of mathematician Professor Harry Bateman, Professor Theodore von Kármán, Assistant Professors Arthur L. Klein, Clark B. Millikan, and Arthur E. Raymond. Albert A. Merrill was Instructor. Others on staff included William H. Bowen, Ernest E. Sechler, and Baily (Ozzie) Oswald. (Pictured at right: A. Merrill wind tunnel, circa 1928.)
Clark Blanchard Millikan (1903–1966) (Physics PhD 1928) Founding Member of the National Academy of Engineering. Professor of Aeronautics 1929–1966. Director of the Southern California Cooperative Wind Tunnel, 1945–1960. Second Director of GALCIT, 1949–1966. Caltech physics graduate student with an early interest in aeronautics. Produced his thesis, "The Steady Motion of Viscous Incompressible Fluids," under Bateman. Played a key role, together with Klein, in the development of the 10-foot tunnel and the testing programs. Contributed both to practical aerodynamics and theoretical fluid mechanics including: effect of turbulence on lift; similarity in turbulent boundary layer and pipe flow; effect of propeller slipstream on aircraft performance; development of multi-engine high-altitude airplanes; jet propulsion; and guided missiles. Supervised all of the testing research carried out in the 10-foot wind tunnel, and had a significant influence on the early development of many of the important airplanes of the 1930s and 1940s. Effectively directed GALCIT beginning in 1942, until he passed away in 1966. Saw the need for and proposed the Southern California Cooperative Wind Tunnel in 1938. Maintained productive relations with industry and government agencies; rebuilt GALCIT after the end of WWII.
Millikan, Clark Blanchard (1928) Some problems in the steady motion of viscous, incompressible fluids; with particular reference to a variation principle. Dissertation (Ph.D.), California Institute of Technology.
Arthur Louis "Maj" Klein (1898–1983) (BS 1921, MS 1924, PhD 1925) Professor of Aeronautics, 1929–1968. In addition to his significant contributions as a teacher of aeronautical engineering, Klein was a legendary designer, and responsible for the engineering and building of the GALCIT 10-foot wind tunnel and related equipment (especially balances and rigging). In 1937 he began spending half his time with Douglas Aircraft, where he had been an intermittent consultant since 1932, and he was instrumental in the design of many of their aircraft over the next 20 years.
Klein, Arthur Louis (1925) The secondary emission from a nickel surface due to positive ion bombardment. Dissertation (Ph.D.), California Institute of Technology.
Klein, Arthur Louis (1924) Secondary emission from metallic surfaces due to positive ion bombardment. Master's thesis, California Institute of Technology.
Theodore von Kármán (1881–1963) Professor of Aeronautics, 1930–1949. First Director of GALCIT, 1930–1949. In 1926 von Kármán was invited to Caltech to give talks on aerodynamics, and review plans for the new wind tunnel. In 1928 he returned to Caltech for an exchange semester, and finally joined the Institute in 1929 as a research associate in aeronautics. In 1930, he was appointed Professor of Aeronautics and Director of GALCIT. von Kármán was a true mechanician of his time and as such he was as accomplished in fluid mechanics as he was in the mechanics of solids and structures. Among his accomplishments were: the first computation of drag for a supersonic projectile; the Fopplevon Kármán plate theory for large deflections; application of dimensional analysis to turbulent flow; the Born-von Kármán lattice model in crystallography; the log-law and von Kármán constant for turbulent boundary layer velocity distribution (law of the wall); the first design of a triaxial testing configuration for the testing of geomaterials; fundamental studies on turbulence; the discovery of the similarity law of transonic flow; and the use of stiffened panels in aircraft construction. He spent much of his time in Washington after 1942. Stepped down as Director in 1949 and became Professor Emeritus. In 1962, at age 81, he was awarded the first National Medal of Science, bestowed in a White House ceremony by President John F. Kennedy. On his characteristic of never declining a lecturing opportunity, he once joked "I can never pass up the opportunity to dominate the conversation for an entire hour."
December—the first complete scale model airplane, the Northrop Alpha, was installed in the 10-foot wind tunnel for design and development testing. (Pictured below: W. Bowen, C. Millikan, and B. Oswald, 1930.)
Maurice Biot (1905–1985) (PhD 1932; student of von Kármán) Biot earned the first PhD awarded by GALCIT. He would become well known in solid mechanics, large deformation continuum mechanics (geology), thermodynamics of solids, and dynamics applied to earthquake engineering. He was a research associate and technical adviser to the National Defense Research Committee at Caltech, 1940–43. Biot wrote three books, including a textbook on applied mathematics co-authored with von Kármán, as well as more than 178 scientific and engineering papers on various topics including elasticity theory, thermodynamics, applied mathematics, soil mechanics, wave propagation and scatter, wing flutter, geophysics, and seismology.
Biot, Maurice A. (1932) Transient oscillations in elastic systems. General theorems. Vibrations of buildings during earthquake. Critical torsional vibrations of accelerated rotating shafts. Dissertation (Ph.D.), California Institute of Technology.
Boeing Aircraft Company tests the YO-31A airplane in the 10-foot tunnel.
GALCIT Meteorology program, 1932–1944. Caltech was one of the five principal centers for training personnel for the Army and Navy during WWII.
Wiley Post completes first solo flight around the world, July 1933; 7 days, 19 hours.
The Douglas DC-1, DC-2 development begins. Over the years, Douglas Aircraft uses the GALCIT 10-foot tunnel more than any other company.
Amelia Earhart becomes the first person to solo the 2,408-mile distance across the Pacific between Honolulu and Oakland, California; first flight where a civilian aircraft carried a two-way radio.
The Suicide Squad—John W. Parsons, Edward S. Forman, and Caltech graduate students Frank J. Malina, Apollo Milton Olin Smith, and Hsue-shen Tsien carry out their first rocket firing on Halloween, 1936, in the Arroyo Seco, the site of the future JPL. The initial tests sparked von Kármán's interest, and he set up Molina with a rocket test facility on campus. Twice their experiments resulted in explosions; the group was sent to the Arroyo Seco. Malina, Tsien, and Smith carry out theoretical analyses on the feasibility of rocket propulsion and flight. From these modest origins, JPL was soon to take form.
Ernest Sechler (1905–1979). (BS 1928, MS 1929, PhD 1933; student of von Kármán) Professor of Aeronautics 1937–1976. Sechler became well known in the aircraft structures field through his pioneering work (initially with von Kármán 1930–35) on buckling of stiffened plates of basic interest in metal aircraft construction and advanced to buckling of cylindrical shells (airplane fuselage and rocket applications). He was an early proponent of using continuum mechanics to analyze structures rather than the then-dominant strength-of-materials approach. Guided by the observation of a failed rocket launch where asymmetrical forces prevailed without buckling of the external structure, he instituted intense efforts to understand the large difference between theoretical and measured buckling loads of cylindrical structures. This culminated in the findings of one of his students, C.D. Babcock. In the words of Y.-C. Fung, Sechler was a person who always found a simpler way to deal with a complex problem, guided and checked by experiment rather than theory alone. This philosophy has become a mainstay of GALCIT teaching and functions.
Start of boundary layer transition work at Caltech, funded by NACA, to look at effect of curvature on transition. Initial studies by Frank Wattendorf, Francis and Milton Clauser, and subsequently, Liepmann.
Sechler, Ernest Edwin (1930) Problems relating to the use of sheet metal in airplane construction. Master's thesis, California Institute of Technology.
Sechler, Ernest Edwin (1934) The ultimate compressive strength of thin sheet metal panels. Dissertation (Ph.D.), California Institute of Technology.
William Rees Sears (1913–2002). (PhD 1938; student of von Kármán) Assistant Professor of Aeronautics, 1940–1941. Served as an instructor at Caltech between 1937–1940 before becoming a professor. Chief of aerodynamics and flight testing at Northrop; headed the team that designed the P-61 (Black Widow) and the flying wing. Joined the faculty of Cornell University in 1946 as the founder and first director of its Graduate School of Aeronautical Engineering. Within a surprisingly few years, the Cornell Graduate School of Aeronautical Engineering was ranked among the world's best. Pioneered research in "ground effect," nonsteady airfoil response and flutter (with von Kármán), wing theory, unsteady flow, magnetohydrodynamics, and wind tunnel design to study transonic flight. (Pictured: Lockheed XP38 model, 1938.)
The growing use of thin metal structures in airplane manufacture, particularly at Northrop Aircraft, promoted von Kármán to revisit the problems of nonlinear buckling, the subject of his inaugural dissertation at Gottingen. With a team consisting of Tsien, Sechler, and Dunn, notable progress was made at GALCIT in understanding the failure of the linear theory and in establishing the appropriate view of post-buckling loads.
Sears, William Rees (1938) A systematic presentation of the theory of thin airfoils in non-uniform motion. Dissertation (Ph.D.), California Institute of Technology.
GALCIT was approached by Palmar C. Putnam, who was backed by electric utilities, to design a large windmill to generate electrical power. von Kármán had Sears and Rannie carry out the aerodynamic design. The final product, a windmill 170 feet in diameter, was erected on Granpa's Knob in Vermont and functioned as planned. After an unusually high wind bent one blade, the sponsors withdrew their support.
Albert Eaton Lombard (?–1983) (BS 1928, MS 1929, PhD 1939) Assistant Professor of Aeronautics and Mechanical Engineering, 1939–1946. Consulting Engineer to Curtiss- Wright Corporation 1929–1939. Lombard eventually joined McDonnell Aircraft Company.
Lombard, Albert Eaton (1939) An investigation of the conditions for the occurrence of flutter in aircraft and the development of criteria for the prediction and elimination of such flutter. Dissertation (Ph.D.), California Institute of Technology.
Hans Wolfgang Liepmann, Theodore von Kármán Professor of Aeronautics, 1945–1985, Emeritus. Third Director of GALCIT, 1972–1985. A member of the National Academy of Engineering and the National Academy of Sciences. Recipient of the National Medal of Science and of the National Medal of Technology. Research includes: boundary layer transition; effect of curvature; turbulent shear flow; transonic flow and boundary layer separation on airfoils. Early work done using 2 by 20-inch transonic tunnel; motivated by "compressibility burble" and buffeting problems on the P-38. Later work with his students in skin friction in supersonic flow; aircraft buffeting; rarified gas dynamics; magnetohydrodynamics and plasma physics; liquid helium; chemistry in turbulent mixing; active boundary layer control. With Roshko wrote classic text, Elements of Gasdynamics. Over 60 PhD students studied under him, and a large academic family has developed through the years. Many went on to be leaders in education and research, in universities, industry, and governments throughout the world.
Homer Joe Stewart (1915–2007) (PhD 1940; student of von Kármán) Professor of Aeronautics, 1942–1980. Starting as a graduate assistant at the GALCIT 10-foot wind tunnel, Stewart worked on meteorology, theoretical and applied aerodynamics, particularly unsteady flow around supersonic airfoils and bodies of revolution. He also participated in many pioneering rocket projects largely through his contributions in orbital mechanics, becoming a section manager of the analytical missile aerodynamics group at JPL. As chief of the research analysis section at JPL, he participated in many rocket projects, including the WAC Corporal, the Corporal, the Sergeant, and the Jupiter C. He was chief of JPL's liquid propulsion systems division when JPL and the Army Ballistic Missile Agency (now the Marshall Space Flight Center) developed and launched Explorer 1.
Stewart, Homer Joseph (1940) The effect of shear instability on the transverse circulation in the atmosphere. Dissertation (Ph.D.), California Institute of Technology.
The Tacoma Narrows Bridge collapsed following severe oscillations induced by wind. von Kármán, who was convinced that the accident resulted from aerodynamic instability, was appointed to a commission investigating the collapse. von Kármán had Rannie and Dunn carry out analyses and wind-tunnel experiments, the results of which proved vital in the redesign of the bridge.
Amman, Othmar H. and von Kármán, Theodore and Woodruff, Glenn B. (1941) The failure of the Tacoma Narrows Bridge. Washington, DC.2-1/2 by 2-1/2 inch Supersonic Tunnel was designed by Tsien and Serrurier starting in 1940 and operated by Puckett in 1941–1942. First continuously operated supersonic wind tunnel to reach M > 4 in the U.S. Used by students until demolition in 1997.
Out of the initial work by Malina's group on rocket propulsion, GALCIT Project No. 1 was organized to apply jet propulsion to assisting the take-off of aircraft. The JATO rocket was born and first solid-propellant rockets shortened the take-off distance of aircraft by up to 50%. (Pictured: S. Corrsin, circa 1943.)
Frank Joseph Malina (1912–1981) (MS 1935 and 1936, PhD 1940; student of von Kármán) Assistant Professor of Aeronautics, 1942–1946. Co-founder GALCIT Rocket Research Project and Jet Propulsion Laboratory (JPL). As a graduate student, he led the group that did the initial research on propellants, rocket motors, and theoretical rocket performance. Gave the first theoretical demonstration (with von Kármán) that long-duration solid propellant rockets were possible. Became the first Acting Director of the Jet Propulsion Laboratory and led effort to build the WAC Corporal. Developed with Parsons the basic formulations of solid and liquid propellants, variations of which have found widespread use up to the present time. (Pictured at right: Frank J. Molina)
Malina, Frank J. (1936) Characteristics of braked, locked and free-wheeling two- and three-bladed propellers. Master's thesis, California Institute of Technology.
Malina, Frank J. (1940) Characteristics of the rocket motor and flight analyses of the sounding rocket. Dissertation (Ph.D.), California Institute of Technology.
Malina, Frank J. (1980) Interview with Frank J. Malina. [Oral History]
Aerojet Engineering Corporation founded by von Kármán and colleagues to manufacture jet-assisted take-off systems for the military.
At the request of the Air Technical Service Command. Army Air Force, von Kármán organizes a graduate curriculum in Jet Propulsion for a group of military officers. The courses and laboratories were taught by Caltech and JPL personnel. Tsien edited these courses into a massive book, "Jet Propulsion," which served as the standard for over ten years.
The GALCIT rocketry group under von Kármán, Tsien, and Malina draft a proposal (dated November 20, 1943) to the military to fund work to develop missiles. This document (the first official memo in the U.S. missile program) was the first to use the name "Jet Propulsion Laboratory."
Transonic wind tunnel, 2-in by 20-in, built by Liepmann. Used by Liepmann with H. Ashkenas and J. Cole to carry out pioneering studies on shock-wave/boundary interactions on high-speed flow over airfoils. Demonstrated the importance of the state of the boundary layer, laminar vs. turbulent, on resulting shock-wave pattern and pressure distribution. Later converted to 4-in by 10-in operation by Ashkenas, Satish Dhawan, and Roshko.
C. C. Lin (PhD 1944) Comprehensive analysis of the stability of two-dimensional parallel flow and stability of compressible boundary layer (with Lees), summarized in his book, The Theory of Hydrodynamic Instability.
Lin, Chia-Chiao (1944) On the development of turbulence. Dissertation (Ph.D.), California Institute of Technology.
Louis Dunn (1908–1979) (BS 1936, MS ME 1937, MS Ae 1938, PhD 1940). Professor of Aeronautics 1945–1954. Director of the Jet Propulsion Laboratory, 1947–1954. Dunn was a close colleague of Sechler and participated with him in the evolution of the "equivalent panel width" characterization of plates undergoing buckling. He became Assistant Director of JPL in 1945–1946 and the Director from 1947–1954, presiding over its early program in rocketry leading up to the development of the Sergeant missile. He left JPL to take over the beginning Atlas missile project for the recently formed Ramo-Wooldridge Corporation.
Dunn, Louis G. (1938) An experimental investigation of the stresses in extruded sections commonly used in aircraft construction. Master's thesis, California Institute of Technology.
Dunn, Louis G. (1940) An investigation of sheet-stiffener panels subjected to compression loads with particular reference to torsionally weak stiffeners. Dissertation (Ph.D.), California Institute of Technology.
Southern California Cooperative Wind Tunnel. Clark Millikan, Director, 1945–1960. Joint venture financed by five Southern California aircraft companies and managed and operated by Caltech. It was one of the first large supersonic wind tunnels. Upgraded to transonic operation in 1955, shut down in 1960 when it became uneconomical to operate.
Paco A. Lagerstrom (1914–1989) Professor of Aeronautics 1952–1966. Professor of Applied Mathematics 1967–1981. Educated as a pure mathematician; recruited by Liepmann from Douglas Santa Monica in 1946. Applied elegant mathematical methods, including asymptotic expansions and similarity solutions based on group theory, to fluid mechanics problems. Wrote classic section on "Laminar Flow Theory" for Princeton Handbook series. Lagerstrom, Cole, van Dyke, and Kaplun pioneered the use of matched asymptotic expansions in solving fluid-flow problems.
Lee A. DuBridge (1901–1994) President of Caltech, 1946–1969.
W. Duncan Rannie (1914–1988) (PhD 1951; student of von Kármán and Tsien) Robert H. Goddard Professor of Jet Propulsion 1947–1981. Early work while still a student on the aerodynamics of suspension bridges and wind power (unfortunately, his analytical findings regarding the stability of the giant windmill were not incorporated into the final design). Went to Northrop to work on the "Turbodyne" project and developed the theories and design procedures for axial compressors that became the basis for much of the progress in gas turbine technology that followed. Became chief of ramjet and combustion research at JPL in 1945, and a member of the GALCIT faculty in 1947. His thesis on heat transfer in turbulent flow was interrupted by the war; was accepted and published in 1951.
Rannie, W. Duncan (1951) Heat transfer in turbulent shear flow. Dissertation (Ph.D.), California Institute of Technology.
Charles Yeager completes first supersonic flight on October 14, 1947, over dry Rogers Lake in California. Yeager rode the X-1, attached to the belly of a B-29 bomber, to an altitude of 25,000 feet. After releasing from the B-29, he rocketed to an altitude of 40,000 feet. He became the first person to break the sound barrier, safely taking the X-1 to a speed of 662 mph, faster than the speed of sound at his altitude.
RAND Report No. 1 U.S. Army Air Forces receive the Douglas study proposing early development of an American communications satellite and attesting to the feasibility of the undertaking. A number of GALCIT faculty and alumni, including Frances Clauser, Paco Lagerstrom, and Hans Liepmann, were involved in the study.
The first analytical study of the detailed flow in axial turbomachines was published by Marble, leading to an extensive program of internal aerodynamics. This work included analysis and experiments of distorted inlet flow by Rannie, Marble, Katz, and Heiser, and extensive experiments by Iura and analysis by Oates and Burggraf to confirm the mechanism of stall propagation in compressor blade rows.
Frank E. Marble (MS 1942, AE 1947, PhD 1948; student of Liepmann) Member of the National Academy of Engineering. Richard L. and Dorothy M. Hayman Professor of Mechanical Engineering and Professor of Jet Propulsion, 1948–1989, Emeritus. Marble was appointed Instructor in Aeronautics in 1948 and Assistant Professor of Jet Propulsion and Mechanical Engineering in 1949 at the time the Jet Propulsion Center was established. That same year he organized a joint effort between the Jet Propulsion Center and JPL, which was the focus of combustion research in propulsion systems over a period of ten years. He has carried out extensive research in the fluid mechanics of turbomachinery, combustion fluid mechanics, acoustics, dynamics of heterogeneous media, and a wide variety of problems associated with high Mach number propulsion systems. In 1999 was awarded the Daniel Guggenheim Medal for Notable Achievements in the Advancement of Aeronautics.
A continuously operating hypersonic tunnel was built in an extension to the original Guggenheim building. This had a 5-in by 5-in test section; the M = 6 leg was put into operation first, followed later by the M = 11 leg. These were operated as the Hypersonics Lab (funded by the Army) up to 1953 under Nagamatsu, and from 1953 to 1970 under Lees. Under Lees' leadership, extensive experimental and theoretical work was carried out on various hypersonic flow topics.
Marble, Frank E. (1947) The rotational motion of an ideal fluid and application to the three-dimensional flow through axial turbomachinery. Engineer's thesis, California Institute of Technology.
Marble, Frank E (1948) Some problems concerning the rotational motion of a perfect fluid. Dissertation (Ph.D.), California Institute of Technology.
Marble, Frank E. (1997) Interview with Frank E. Marble. [Oral History]
Clark Blanchard Millikan becomes second director of GALCIT (1949–1966).
Hsue-shen Tsien (PhD 1939; student of von Kármán) Assistant Professor of Aeronautics, 1943–1946; Robert H. Goddard Professor, 1949–1955. Director of the Guggenheim Jet Propulsion Center, 1949–1955. Scientist who was von Kármán's protégé, colleague, and heir-apparent. Became the first Director of the Daniel and Florence Guggenheim Jet Propulsion Center established at Caltech in 1949. Seminal work in many areas, including aeronautics, applied mechanics, rocketry, and control. Discovered similarity laws of hypersonic flow; designed GALCIT's first supersonic tunnel. Was instrumental in advising the U.S. military during WWII. Sadly, Tsien was forced to leave the U.S. in 1955; subsequently played a key role in developing Chinese missile research. In addition, he is widely considered the father of the modern Chinese space program.
Tsien, Hsue Shen (1939) Problems in motion of compressible fluids and reaction propulsion. Dissertation (Ph.D.), California Institute of Technology.
Allen Puckett (PhD 1949; student of von Kármán) Built 2-1/2 -in by 2-1/2 -in supersonic tunnel during 1941–1942 and designed a larger tunnel (3-ft by 3-ft) in 1942 that was built at Ballistic Research Laboratories, Aberdeen Proving Ground, MD. Also designed smaller tunnels for JPL. Conducted supersonic airfoil studies and developed delta wing theory with H. J. Stewart. Taught compressible flow theory with Liepmann to Kelly Johnson and others at Lockheed at end of WWII. Co-author (with Liepmann) of pioneering text, Aerodynamics and Compressible Flow. Went on to become CEO and Chairman of Hughes Aircraft.
Puckett, Allen E. (1949) Supersonic wave drag on thin airfoils. Dissertation (Ph.D.), California Institute of Technology.
Max L. Williams (MS 1947, AE 1948, PhD 1950; student of Sechler) Member of the National Academy of Engineering. Professor of Aeronautics, 1951–1966. Considered, along with George Irwin, to be the father of fracture mechanics. With Sechler, generalized formulation of the Kirchhoff/Timoshenko plate equations for bending and in-plane loading. Investigated the stress distribution at the corner of the wing-fuselage connection for arbitrary re-entrant angles. The limit case of zeroincluded angle, simulating a crack, led him to the first analytical publication of the square root singularity in fracture problems, which established the similarity of all (brittle) fracture problems in terms of a stress intensity factor which characterized the severity of stresses at the tips of cracks. Established one of the first dynamic fracture laboratories in the U.S. Examined the nature of the stress singularity at interface cracks between dissimilar materials (earthquake applications); became a seminal contribution to adhesive fracture issues in the 1990s. His research led to far-reaching changes in design practices regarding the structural integrity of solid propellant rocket motors in terms of mechanics principles, via both fracture and adhesion investigations. Became a major force behind instituting viscoelastic material characterization and extension to viscoelastic fracture mechanics. Had a major international influence on the evolving understanding of the time-dependent behavior of polymers. Founded The International Journal of Fracture.
Williams, Max L. (1948) Maximum stress in a cylindrical bar of double wedge cross section under torsion. Engineer's thesis, California Institute of Technology.
Williams, Max L. (1950) The plate problem for a cantilever sector of uniform thickness. Dissertation (Ph.D.), California Institute of Technology.
Yuan-Cheng Fung (PhD 1948; student of Sechler) Member of the National Academy of Engineering, the National Academy of Sciences, and the Institute of Medicine. Professor of Aeronautics, 1951–1966. Considered the father of biomechanics. His early interest in shell structures focused initially on stability issues of curved plates and shells of variable thickness. His interest in airplane stability and fluid-structures interaction precipitated by von Kármán vortices lead to an extended and long involvement in aeroelasticity as documented through his 1955 Introduction to the Theory of Aeroelasticity and which provided leadership into the supersonic age. Author of Fundamentals of Solid Mechanics. Significant work in formulating structural stability problems in statistical terms, especially in connection with supersonic aircraft. His interest in shell structures had a profound influence on his research when he observed in Harold Wayland's laboratories (Caltech Mechanical Engineering) the ease with which blood cells moved through blood vessels of much smaller diameter; observing that a blood cell exhibits a low (~zero) internal pressure to allow the relative flexibility of its shell/membrane. On sabbatical leave in Germany in 1958–1959, he observed that the disciplines of neither medicine nor biology dealt with the concept of mechanical forces in their endeavors. This observation ultimately led to a new career in biomechanics, which he started in the Caltech Firestone Laboratories with the mechanics of lung tissue and its function, but which he then continued very successfully at the University of California, San Diego. (Pictured above: M. Williams and Yuan-Cheng Fung, 1970.)
Fung, Yuan-Cheng (1948) Elastostatic and aeroelastic problems relating to thin wings of high speed airplanes. Dissertation (Ph.D.), California Institute of Technology.
The Jet Propulsion Center and JPL establish a joint research program on combustion problems in propulsion systems directed by Marble. Among its accomplishments during the next decade were the first analysis of ignition and combustion in mixing layers between combustible gas and hot combustion products (Adamson); demonstration of the mechanism by which flames are stabilized in the wakes of solid bodies; development of scaling laws which allowed sizing and spacing of flame-holders in air-breathing propulsion engines (Zukoski and Broman); establishment of the mechanism of high-frequency combustion instability in gas turbine afterburners (Rogers and Barker). The final investigation of this program was a series of combustion instability experiments in solid propellant rockets by Brownlee, the data from which constitute the most complete set of organized rocket firings.
Merrill Wind Tunnel Closed-return tunnel used for teaching and research projects; 200 mph, 3-ft by 4-ft test section. Named after Albert Merrill, who helped with the design, the tunnel was installed in 1950 and was decommissioned a little more than 50 years later.
Julian Cole (MS 1946, PhD 1949) Professor of Aeronautics, 1951–1967, Professor of Applied Mathematics, 1967–1971. Contributions to transonic aerodynamic theory and singular perturbation methods.
Cole, Julian D. (1947) On the transonic flow past thin airfoils. Engineer's thesis, California Institute of Technology.
Cole, Julian D. (1949) Problems in transonic flow. Dissertation (Ph.D.), California Institute of Technology.
Tsien introduces the concepts of contemporary control theory into the control of propulsion systems. Among the consequences of these studies were the introductory investigations of servostabilization of combustion instability in monopropellant and bipropellant liquid rocket motors.
Lester Lees (1920–1986) Professor of Aeronautics and Environmental Engineering, 1953–1985. As director of the Hypersonics Laboratory from 1953–1970, he led investigations into key technological aspects of ballistic missiles and reentry body design including leading-edge shock-wave influence on boundary layers, hypersonic wakes, shock-wave/boundary interactions, rarified flow about blunt slender bodies, and physics of ablation. Director of Caltech's Environmental Quality Laboratory from 1970 until 1974.
William H. Pickering (1910–2004) (BS 1932, MS 1933, PhD 1936) Professor of Electrical Engineering, Emeritus, 1940–1980. Director of JPL, 1954–1976. In 1944, Pickering organized the electronics efforts at JPL to support guided missile research and development, becoming project manager for Corporal, the first operational missile JPL developed. From 1954 to 1976 he was Director of JPL, and oversaw the development of Explorer 1, Pioneer 4 (the first successful U.S. circumlunar space probe), the Mariner flights to Venus and Mars in the early to mid-1960s, the Ranger photographic missions to the moon in 1964–65, and the Surveyor lunar landings of 1966–67. In 1975, recalling the achievement of Explorer 1 and its impact on a new era of space exploration, Pickering stated "The event was symbolic of the mixing process between engineering and science, between the world and the research laboratory...it had mixed rocket technology with the universe, and reduced astronautics to practice at last."
Pickering, William H. (1936) A Geiger counter study of the cosmic radiations. Dissertation (Ph.D.), California Institute of Technology.
Anatol Roshko (MS 1947, PhD 1952; student of Liepmann) Member of the National Academy of Engineering, the National Academy of Sciences, and the American Academy of Arts and Sciences. Theodore von Kármán Professor of Aeronautics, 1955–1994, Emeritus. Acting Director, Graduate Aeronautical Laboratories, 1985–87. Experimental fluid mechanics. Shock-wave boundary-layer interaction. Boundary-layer effects in shock-tube design. Subsonic and supersonic separated flows: wake structure, base pressure, bluff-body modelling, vortex shedding, flow-induced vibration. New insights into turbulent-shear-flow structure and mixing, with Garry Brown and Gene Broadwell. With Liepmann wrote classic text, Elements of Gasdynamics.
Roshko, Anatol (1952) On the development of turbulent wakes from vortex streets. Dissertation (Ph.D.), California Institute of Technology.
Donald Coles (MS 1948, PhD 1953; student of Liepmann) Member of the National Academy of Engineering. Professor of Aeronautics, 1956–1996, Emeritus. Known for his meticulous experimental studies and analysis of data, particularly in turbulent boundary layers. Discovered the "Law of the Wake" (1956); the complex transition between states in Taylor-Couette flow (1965); key participant in the influential 1968 Stanford Boundary Layer Conference; study of similarity structure of entrainment in turbulent spot (with Cantwell and Dimotakis); synthetic turbulent boundary layer (with Barker, Savas, Arakeri); wake structure of stalled airfoil (Wadcock) and cylinder (Cantwell) with the "flying hot wire" technique; writing monograph tentatively now titled Topics in Turbulent Shear Flow.
Coles, Donald Earl (1953) Measurements in the boundary layer on a smooth flat plate in supersonic flow. Dissertation (Ph.D.), California Institute of Technology.
Edward E. Zukoski (1927–1997) (MS 1951, PhD 1954) Professor of Jet Propulsion and Mechanical Engineering, 1957–1995. Thesis work in the problem of combustion stability in ramjet engines and gas turbine afterburners. His work laid the foundations of the flame-holding mechanism. He and his students made major contributions to magneto-gasdynamics, aeroacoustics, problems of propellant control under microgravity conditions, and hydrogen/air mixing in supersonic combustion ramjet propulsion systems. Zukoski researched building fires in the 1960s, and with Kubota developed the first comprehensive description of convective fire plumes.
Zukoski, Edward Edom (1954) Flame stabilization on bluff bodies at low and intermediate Reynolds numbers. Dissertation (Ph.D.), California Institute of Technology.
Max L. Williams publishes classical paper on the structure of the crack tip stress-field, which forms the basis of modern fracture mechanics. This was followed in 1959 by the identification of the stress-field for an interface crack which became the foundation of adhesion mechanism and fracture of heterogeneous materials, composites, and thin films. Sputnik 1—October 4, 1957, Russian launch of first artificial satellite of the Earth, Sputnik 1. This event began the space race by galvanizing interest and action on the part of the American public to support an active role in space research, technology, and exploration.
Explorer 1—the first U.S. Earth satellite was developed by Caltech and the Jet Propulsion Laboratory and carried the US-IGY (International Geophysical Year) experiment of James A. Van Allen that resulted in the discovery of the radiation belt around the Earth.
Toshi Kubota (1927–1999) (MS 1952, PhD 1957; student of Lees). Professor of Aeronautics, 1959–1990. From 1957 to 1959 Kubota was a research associate. He became a faculty member in 1959 and was promoted to full Professor in 1971. Kubota worked on fluid mechanics, with an emphasis on hypersonic flows, including wakes and shock layers. He also worked on supersonic turbulent shear flows and supersonic boundary layer separation. He supervised a number of students that worked in the Hypersonics Laboratory.
Kubota, Toshi (1957) Investigation of flow around simple bodies in hypersonic flow. Dissertation (Ph.D.), California Institute of Technology.
The 17-in shock tube was designed to operate at very low pressure in order to carry out shock-wave structure measurements with electron beams and mass spectrometry. The large size has been used to advantage at atmospheric pressure to study the focusing of weak shocks, shock-wave propagation through turbulence density fluctuations, and shock-wave induced instability; currently being used in converging shock studies.
The National Aerospace Laboratories (NAL) of India was established in 1959; its first three directors were GALCIT alumni: founding director P. Nilakantan (MS 1942), director from 1959–1964; S. R. Valluri (MS 1950 PhD 1954), director from 1965–1984; and R. Narasimha (PhD 1961), director from 1984–1993. The early years (1960–67) were spent in setting up wind tunnels across Bellandur Lake; notably the 1.2 meter trisonic blowdown wind tunnel which is operational to this day. Then followed a decade of facility build-up and the creation of R&D divisions encompassing practically every facet of aeronautics: theoretical and experimental aerodynamics, structures, materials, propulsion, electronics and systems. Beginning in the 1980s, NAL was further transformed, making its mark in civil aviation, parallel processing, aerospace electronics, surface technologies, and computational fluid dynamics.
Valluri, S. R. (1954) Some studies in the fundamental parameters of fatigue. Dissertation (Ph.D.), California Institute of Technology.
R. Narasimha Narasimha, Roddam (1961) Some flow problems in rarefied gas dynamics. Dissertation (Ph.D.), California Institute of Technology.
(Pictured above: C. Millikan, 1960.)
GALCIT is renamed and G now stands for "Graduate" rather than "Guggenheim."
Yuri Gagarin First person to orbit the Earth, April 12, 1961. The mission's maximum flight altitude was 327,000 meters. The maximum speed reached was 28,260 kilometers per hour. The flight lasted 108 minutes. Reentry was controlled by computer. Gagarin did not land inside of Vostok 1; he ejected from the spacecraft and landed by parachute.
Kármán Laboratory of Fluid Mechanics and Jet Propulsion dedicated. Funding provided principally by the Aerojet Corporation.
Firestone Flight Sciences Laboratory dedicated. Funding provided principally by the Firestone Corporation with the support of Leonard Firestone.
Gerald B. Whitham, Fellow of the Royal Society. Charles Lee Powell Professor of Applied Mathematics, 1962–1998, Emeritus. Approximate methods in wave propagation stimulated experimental and numerical studies, particularly in shock dynamics, nonlinear steepening, wave focusing, and sonic boom propagation. Wrote influential text, Linear and Nonlinear Waves.
Bradford Sturtevant (1933–2000) (MS 1956, PhD 1960; student of Liepmann) Hans W. Liepmann Professor of Aeronautics, 1962–2000. Worked on 17-in shock tube as a graduate student and faculty member. Taught and researched shock waves and nonsteady gas dynamics. His projects included experimental and theoretical investigations of the propagation of shock waves through nonuniform media, including shockexcited
Sturtevant, Bradford (1960) The effusion of charged particles from a shock heated gas. Dissertation (Ph.D.), California Institute of Technology.
Rayleigh-Taylor instability; hydrodynamic sources of earthquakes and harmonic tremor; sonic boom, the effects of dissociation relaxation in hypervelocity flow; shock-wave physics of extracorporeal shock wave lithotripsy, including the focusing of weak shock waves; the fluid mechanics of explosive volcanic eruptions, including the explosive evolution of dissolved gas from rapidly depressurized liquids.
Peter Lissaman (MS 1954, PhD 1966; student of Millikan) Assistant Professor of Aeronautics, 1962–1968. Research into applied aerodynamics and ground effect.
Lissaman, Peter B. S. (1966) A linear solution for the jet flap in ground effect. Dissertation (Ph.D.), California Institute of Technology.
Fred E. C. Culick, Richard L. and Dorothy M. Hayman Professor of Mechanical Engineering and Professor of Jet Propulsion, 1963-2004, Emeritus. Beginning with his M.I.T. Sc.D. thesis, has worked on both theory and experiment for the general problem of unsteady motions in combustion chambers. His own work and surveys of international works are covered in a monograph published by Cambridge University Press on combustion instabilities and related problems in gas and liquid rockets, ramjets, gas turbines and thrust augmentors. Work on active control of combustion dynamics grew out of earlier research on problems of robotics and control of dynamical systems. Actively involved for three decades in research and advisory activities at the Jet Propulsion Laboratory. Personal international collaborations have led to editing translations of two Russian monographs on theory and experiment of combustion instabilities in liquid propellant rockets. Interests in fundamentals and history of aerodynamics and aircraft dynamics motivated a monograph on basic airfoil theory also to be published by Cambridge University Press. Serves as Chairman of an AIAA project he co-founded in 1978 to construct two full-scale replicas of the 1903 Wright ‘Flyer,' one of which is displayed in the FAA building in Los Angeles, and the second, a flying replica, is nearly completed, at Flabob Airport, California. Built the first complete (1/6 scale) wind tunnel model of the ‘Flyer' and acquired data to explain the flight dynamics of the first airplane. Has authored numerous papers and presentations on various aspects of aeronautical history.
Charles Babcock (1935–1988) (MS 1958 PhD 1962; student of Sechler) Professor of Aeronautics and Applied Mathematics, 1963–1988. Reconciled theory and experiments on buckling of cylindrical shells through the use of exceedingly closely toleranced shells (electroplating process) and control of the edge boundary conditions. Used imperfection theory to place the problem of shell stability and structural reliability on a different level. Applications to buckling of large liquid storage tanks under earthquake conditions and collapse of sea-bed deployed oil pipe lines. Knauss and Babcock studied the important problem of layer delamination in damaged composite panels under in-plane compression from a combined fracture mechanics and bucking point of view. Vice Provost of Caltech under R. Vogt until Babcock's untimely death in 1988.
Babcock, Charles D. (1962) The buckling of cylindrical shells with an initial imperfection under axial compression loading. Dissertation (Ph.D.), California Institute of Technology.
Babcock, Charles D. (1962) The buckling of cylindrical shells with an initial imperfection under axial compression loading. Dissertation (Ph.D.), California Institute of Technology.
Applied Mathematics is established as a new graduate Option and splits off from GALCIT.
Philip G. Saffman, Fellow of the Royal Society. Theodore von Kármán Professor of Applied Mathematics and Aeronautics, 1964–1999, Emeritus. Influential teacher and researcher on fluid mechanics. Emphasized role of vorticity and vortex dynamics in fluid mechanics. Studied vortex instability, reconnection, and dynamics of arrays of vortices. Author of Vortex Dynamics, based on his course of the same name.
Miklos Sajben, Assistant Professor of Aeronautics, 1964–1970. Student of Lees, research into inlet aerodyamics. Went to Douglas Research Laboratory and eventually joined the University of Cincinnati as a professor.
Wolfgang G. Knauss (BS 1958, MS 1959, PhD 1963; student of Williams) Member of the National Academy of Engineering. Theodore von Kármán Professor of Aeronautics and Applied Mechanics, 1965–2004, Emeritus. Motivated by the need to understand failure of solid propellant rocket fuels, provided the main experimental background for understanding the role of viscoelasticity in fracture propagation, and established the first comprehensive (linearly) viscoelastic fracture theory. Studied high-rate crack extension in brittle solids and resolved a longstanding dichotomy in dynamic fracture. Detailed highspeed photography demonstrated that the theoretically modeled fracture process was unrealistic and that multiple fractures at the crack tip controlled both the speed and the phenomenon of crack branching. Demonstrated the important influence of dilatational changes on the time dependence of the constitutive relationships for polymers in the nonlinear range. Pioneered work in nano-mechanics and reliability through the use of probe microscopy. Early diversions into geology and biomechanics (radial keratotomy, human intervetebral disk) investigations attest to the breadth of mechanics supported by the GALCIT spirit.
The 6-inch shock tube built to study ionized gases at high shock Mach numbers (Roshko, Smith). Used also to study focusing of strong shock waves in cones (Storm, Setchell), refraction of shocks through density gradients (Haas), and numerous student projects.
Knauss, Wolfgang Gustav (1963) Rupture phenomena in viscoelastic materials. Dissertation (Ph.D.), California Institute of Technology.
Wilhelm Behrens (PhD 1966; student of Lees) Assistant Professor of Aeronautics, 1967–1973. Research into hypersonic flow including the structure and stability of hypersonic wakes, separated flow on lifting bodies, and viscous interactions. Joined TRW in 1973; held positions including Manager of Fluid Thermophysics Department, Northrop Grumman.
Behrens, Hermann Wilhelm (1966) Flow field and stability of the far wake behind cylinders at hypersonic speeds. Dissertation (Ph.D.), California Institute of Technology.
Francis Clauser (BS 1934, MS 1935, PhD 1937; student of von Kármán) Professor of Engineering, 1969–1980; Clark Blanchard Millikan Professor of Engineering, Emeritus. Francis Clauser's early career included a job as research aerodynamicist at Douglas Aircraft after which he went on to teach at Johns Hopkins University. At Hopkins he founded and chaired the Department of Aeronautics. From there he went to the University of California, Santa Cruz, where he was a vice chancellor and professor of engineering. He returned to Caltech in 1969 to become the Chair of the Division of Engineering and Applied Science.
Clauser, Francis H (1937) The effect of curvature on the transition from laminar to the turbulent boundary layer. Dissertation (Ph.D.), California Institute of Technology.
Clauser, Francis H. (1937) New methods of solving the equations for the flow of a compressible fluid. Dissertation (Ph.D.), California Institute of Technology.
Gordon Harris, Assistant Professor of Aeronautics, 1969–1972. Research into vehicle aerodynamics.
Apollo Program successful, first astronauts land on the Moon and return to Earth.
Harold Brown becomes Caltech's third President (1969–1977).
At the request of the National Bureau of Standards, a study was undertaken by Marble, Rannie, and Zukoski to formulate a long-term program of analytical and experimental research aimed at a rational understanding of fire propagation in large building structures. This work led, in turn, to detailed experiments and computations by Zukoski and Kubota of fire spread in single rooms.
Hans Wolfgang Liepmann becomes third Director of GALCIT (1972–1985).
In 1972, the Indian Space Research Organization (ISRO) was brought under the Department of Space, and in the same year, GALCIT alumnus S. Dhawan (Engineer 1949, PhD 1951) became the Chairman of ISRO. He served in that capacity until 1995. Prior, he served as the Director of the Indian Institute of Science (1962–1981).
Dhawan, Satish (1949) On the design and use of a flexible nozzle for the Galcit tronsonic tunnel. Engineer's thesis, California Institute of Technology.
Dhawan, Satish (1951) Direct measurements of skin friction. Dissertation (Ph.D.), California Institute of Technology.
Cyrogenic shock tube used to study first and second shock waves in liquid He(II). Fluid mechanics of liquid helium studied for the next decade by Liepmann and students, Cummings, Dimotakis, Laguna, Moody, Rupert, Turner, Torcyzinski, and Wise.
Candel and Marble establish that the passage of regions of non-uniform entropy through a choked nozzle produced a large acoustic source and made a significant contribution to the noise emitted by jets from propulsion devices.
Brown and Roshko discover two-dimensional coherent structures in high Reynolds number shear flow, upsetting traditional views of "fully turbulent flow." Later studies show streamwise streaks, highly intermittment entrainment, and the existence of a "mixing transition" at a critical Reynolds number. (Pictured above: coherent structures in shear layer, and pictured below: turbulent spot.)
Paul E. Dimotakis (BS 1968, MS 1969, PhD 1973; student of Liepmann) John K. Northrop Professor of Aeronautics and Professor of Applied Physics, 1975–present. Chief Technologist, Jet Propulsion Laboratory, 2006–present. His investigations include work on liquid helium superfluid mechanics, turbulence and turbulent mixing, chemically reacting flows and combustion, flow control, and aerooptics. Contributed developments in instrumentation and data acquisition, laser diagnostics, high-speed digital imaging technology, image correlation and particle-streak velocimetry.
Dimotakis, Paul E (1973) Investigation of supercritical heat flow in helium II. Dissertation (Ph.D.), California Institute of Technology.
Bruce Murray, Professor of Planetary Science and Geology, 1960–2001, Emeritus. Director of the Jet Propulsion Laboratory, 1976–1982. Oversaw the Viking landings on Mars and the Voyager mission through Jupiter and Saturn encounters.
Garry L. Brown, Professor of Aeronautics, 1977–1982. Contributions to structure and mixing in turbulent shear flow; innovative design of experimental facilities. Became director of the Australian Aeronautical Research Laboratory. Returned to the U.S. to serve as Chair of the Department of Mechanical and Aerospace Engineering at Princeton University.
The study of the distortion and stretching of flames in vortex structures was begun by Marble, Karagozian, and Candel.
Paul J. MacCready (1925–2007) (PhD 1952) With Lissaman, created the first practical human-powered aircraft, the Gossamer Condor, and thereby won the Kremer prize in 1977. The award-winning plane was built out of piano wire, bicycle parts, and mylar.
MacCready, Paul B (1952) Investigation of atmospheric turbulence. Dissertation (Ph.D.), California Institute of Technology.
Marvin L. Goldberger becomes the fourth President of Caltech (1978–1987).
Structure of sublayer and entrainment in turbulent spot determined by Cantwell, Coles, and Dimotakis.
(Pictured below left: F. Culick and Wright Flyer model, 1979; below right: H.Hornung, ABC Nightline, 1987.)
Super Sonic Shear Layer Facility established. Designed for the study of molecular mixing in high-speed flows from high subsonic to supersonic. Unique facility that relies on the fast chemical kinetics between hydrogen and fluorine to mark fluid that is mixed at a molecular level.
Launch of Columbia, first space shuttle.
Lew Allen, Jr., Director of Jet Propulsion Laboratory, 1982–1991.
Ares J. Rosakis, Theodore von Kármán Professor of Aeronautics and Mechanical Engineering, 1982–present. Fifth Director of GALCIT, 2005–2009. The 2005 William M. Murray Medalist and Lecturer for the Society for Experimental Mechanics (SEM), in recognition of his contributions to the development and application of advanced methods for accurate measurement of transient, dynamic phenomena. Developed the Coherent Gradient Sensing (CGS) method for optically determining deformation gradients under arbitrarily rapid loading conditions. Provided applications in determining the curvature of silicon wafers used in micro-electronics industry. Experimental development (with Ravichandran) of high-speed thermography to follow the evolution of energy conversion at the tips of rapidly moving cracks and in the evolution of shear bands. Other interests include dynamic fragmentation, shear dominated intersonic rupture of inhomogeneous solids, rupture mechanics of crustal earthquakes, shielding of spacecraft from hypervelocity micrometeoroid impact threats, and reliability of thin films. His most recent work in seismology has resulted in the discovery of the phenomenon of super-shear fault rupture and in the experimental visualization of propagating, self-healing, frictional ruptures.
High-Speed Imaging Facility This facility specializes in the real-time visualization of dynamic deformation and failure events using laser interferometry, ultra-high-speed photography of various types, and high-speed infrared thermography. It is unique since it is capable of simultaneously measuring both deformation and temperature fields in the sub-microsecond regime.
Anthony Leonard (BS 1959) Theodore von Kármán Professor of Aeronautics, 1985–2005, Emeritus. Numerical simulation of fluid motion. Direct simulation of the Navier- Stokes equations and studies of turbulence and mixing. Vortex element and vortex particle methods for separated flows. Discovered the role of the "Leonard Stresses" in large-eddy simulations. Simulation of flow-structure interactions near wake regions of oscillating bodies.
Among the problems posed by the hypersonic ramjet propulsion system was the injection and rapid mixing of the hydrogen fuel with air at Mach numbers on the order of six. Marble proposed a mechanism by which the mixing of low density hydrogen with air could be greatly enhanced by carefully controlled weak shock waves. Over a period of five years the shock-enhanced injection system was developed by Marble, Zukoski, and their students, and was successfully demonstrated by Waitz at the NASA Langley Research Center.
Hans G. Hornung, C. L. "Kelly" Johnson Professor of Aeronautics, 1987–2005, Emeritus. Foreign Member of the National Academy of Engineering. Fourth Director of GALCIT, 1987–2003. After serving as director of the DFVLR in Gottingen from 1980–1987, Hornung became the fourth Director of GALCIT. With a special interest in hyper-velocity and nonequilibrium flow, he initiated construction of the F.E.C. Culick and Wright Flyer model, 1979.
T5 shock tunnel and a series of investigations into chemical reaction rate effects on shock standoff, boundary layer stability and transition, transverse jet interactions, facility characterization and advanced diagnostics, and vorticity production behind curved shocks.
Thomas E. Everhart becomes the sixth President of Caltech (1987–1997).
The T5 facility at GALCIT is a free piston shock tunnel, and is named T5 because it is the fifth in a series of shock tunnels built by or under the supervision of R. J. Stalker, H. G. Hornung, and colleagues (the previous four are in Australia). The facility is capable of producing flows of air or nitrogen up to specific reservoir enthalpy of 25 MJ/kg, reservoir pressure of 100 MPa, and reservoir temperature 10,000 K. It achieves this by using a free piston to adiabatically compress the driver gas of the shock tunnel to very high pressure, as high as 130 MPa. These conditions are needed to simulate the real gas effects of chemical dissociation and reaction that occur in flows about vehicles flying at sub-orbital speeds through the atmosphere. The test section can accommodate models up to 8 inches in diameter and the useful test time is 1–2 ms. Construction started in 1989 and the first test was in 1990.
Guruswami Ravichandran, Professor of Aeronautics and Mechanical Engineering, 1990– present; John E. Goode, Jr., Professor, 2005–present. Sixth Director of GALCIT, 2009–present Experimentalist whose work has covered dynamic response characteristics of materials; thermodynamics of the energy conversion process in large deformation and rate dependent plasticity phenomena. In deviating from the standard test routines associated with uniaxial compression behavior, his interest has centered on generating multiaxial stress states dynamically using high-strain rates, with applications to impact and penetration problems in metals, ceramics, and heterogeneous materials including composites and sandwich structures. Experimental development (with Rosakis) of highspeed thermography to follow the evolution of energy conversion at the tips of rapidly moving cracks and in the evolution of shear bands. Time-dependent and multiaxial behavior of amorphous metals and metallic glasses. Investigation of large deformation elastostriction behavior in materials that can potentially be used as actuators. Investigation of 3D deformation in biomaterials and cell motility.
High Strain Rate Laboratory This facility was established to investigate the dynamic deformation, damage, and failure of materials. It consists of Split-Hopkinson (Kolsky) bars, plate impact facilities, gas and propellant guns, and a variety of high-speed diagnostics. Specific contributions include the study of the conversion of plastic work into heat, techniques for investigating the dynamic multi-axial behavior of ceramics and composites, and the study of shock waves through heterogeneous media.
Edward C. Stone, David Morrisroe Professor of Physics, Vice Provost for Special Projects. Director of the Jet Propulsion Laboratory, 1991–2001.
Dale Pullin, Professor of Aeronautics, 1991–present; Theodore von Karman Professor of Aeronautics, 2006–present. Research interests include: Computational and theoretical fluid dynamics, vortex dynamics, theory and simulation of complex turbulent flow including mixing, compressible turbulence, shock-driven turbulence. Structure-based methods for large-eddy simulation and multiscale modeling of turbulent flows. Numerical simulation and modeling of wall-bounded flows at ultra-high Reynolds number. Dynamics of vortex and dipole sheets. Geometrical structure of turbulence, application of differential geometry, multiscale diagnostic and automated clustering techniques to the characterization and classification of eddy geometry in turbulence over all scales. Hydrodynamic stability, shock-driven instabilities, vorticity deposition mechanisms and transition to turbulence in impulsive unstable flows. Large-eddy simulation of Richtmyer-Meshkov instability in converging geometries and in fluids with exotic equations of state. Development of high-order, asymptotically and energy stable, finite-difference stencils with step changes in grid resolution for fluid simulation. Direct numerical simulation of compressible flows including full resolution of internal shock structure. Hybrid, shock-fitting, shock-capturing but smoothly non-dissipative numerical schemes for detonation driven and other flows. Eulerian description of mixed phase solid/fluid flows including phase-change modeling.
Morteza Gharib (PhD 1981; student of Roshko) Professor of Aeronautics, 1992–2001; Professor of Aeronautics and Bioengineering, 2001–2002; Hans W. Liepmann Professor of Aeronautics and Bioengineering, 2002–present. Research interests have included advanced sensors and diagnostic systems such as digital particle image velocimetry, thermometry, 3-D particle velocimetry and micro-optical systems. His fluid mechanics research interests include vortex flows, unsteady aerodynamics, two-phase flows, and flow-induced vibration. Biomechanics work includes cardiovascular mechanics and fluid dynamics, eye optics and fluid mechanics. Co-founder of the Bioengineering Option at Caltech and Director of the Charyk Laboratory of Bio-Inspired Design at GALCIT.
Gharib, Morteza (1983) The effect of flow oscillations on cavity drag, and a technique for their control. Dissertation (Ph.D.), California Institute of Technology.
Joseph E. Shepherd (PhD 1981; student of Sturtevant) Professor of Aeronautics and Mechanical Engineering, 1993–present. Developed Explosion Dynamics Laboratory and studies combustion, fuel properties, and fluid dynamics relevant to explosion initiation and propagation. Applications include: novel propulsion systems (pulse detonation engines); evaluation of explosion hazards in industrial processes, transportation systems, and nuclear facilities; and investigation of accidental explosions. Experimental studies are being carried out on ignition and propagation of flames, transition from flames to detonation, propagation of detonations and shock waves, response of structures to explosions, application of detailed chemical chemistry to combustion modeling, and the simulation of high-explosive detonation.
Shepherd, Joseph Emmett (1981) Dynamics of vapor explosions: rapid evaporation and instability of butane droplets exploding at the superheat limit. Dissertation (Ph.D.), California Institute of Technology.
Michael Ortiz, Member of the American Academy of Arts and Sciences, Professor of Aeronautics and Applied Mechanics, 1995–2000; Professor of Aeronautics and Mechanical Engineering, 2000–2004; Dotty and Dick Hayman Professor, 2004–present. Computational methods in mechanics. Scalable adaptive finite element software. Quasi-continuum software for advanced mixed atomistic-continuum simulations. Multiscale models of material failure, particularly the behavior of individual atoms and their electrons. Other focal areas of activity: the development of informed continuum models for plasticity and fatigue crack growth; the development of appropriate cohesive zone models for cracks and interfaces under fatigue and corrosion conditions; and the incorporation of continuum mass transport methods in the quasicontinuum method. Advanced numerical methods for the computation of shells and flexible structures.
David Baltimore, Robert Andrews Millikan Professor of Biology, becomes the seventh President of Caltech (1997–2006).
Demolition of 10-foot tunnel and rehabilitation of basement and subbasement of Guggenheim begins.
Ludwieg Tube This facility allows Mach 2.3 flow in an 8-in by 8-in in test section with a test time of 80 milliseconds. The flow is produced by unsteady expansion following the bursting of a diaphragm separating the test section from the dump tank. A novel suction scheme removes the boundary just upstream of the throat. The concept was first proposed in 1955 by Hubert Ludwieg. Construction started in 1998; the first test was in 2001. (Pictured: Lucas Wind Tunnel inaugural.)
Micro Device Reliability Laboratory (MDRL) A class one clean room area which houses the new MDRL is established in the basement of Firestone. This facility specializes in the fullfield interferometric measurement of wafer curvature and thinfilm stress in large 300-mm production wafers as well as in the in-situ inspection of large space mirror segments.
Charles Elachi (MS 1969, PhD 1971; student of Papas) Professor of Electrical Engineering and Planetary Science. Director of the Jet Propulsion Laboratory, 2001–present.
Elachi, Charles (1971) Electromagnetic wave propagation and source radiation in space-time periodic media. Dissertation (Ph.D.), California Institute of Technology.
Lees-Kubota Lecture Hall dedicated on January 8, 2001. Located in the Guggenheim Building on the site of the old Aero Library, this was made possible by donations of former students, particularly Denny R. S. Ko. (Pictured below: detail from exterior of Guggenheim building.)
John W. Lucas Adaptive Wall Wind Tunnel commissioned on October 3, 2002. It was built as a replacement for the 10-foot tunnel. The Lucas AWWT uses adaptive wall technology in the test section to reduce and even eliminate the need for data corrections required in straight-wall tunnel tests. While the tunnel is operating, pressure measurements are taken along the floor and ceiling of the test section; combined with the current displacement profiles, a one-step predictive algorithm determines the required wall contour for the current model configuration and adapts the walls to match. The system effectively "tricks" the air into thinking it is in an infinite flowfield, rather than confined by the walls of the tunnel. This idea was developed by Sears in the 1970s.
75th Anniversary of the Graduate Aeronautical Laboratories celebrated at Caltech.
Ares J. Rosakis becomes the fifth Director of GALCIT.
Small Particle Hypervelocity Impact Facility (SPHIR) SPHIR is a joint GALCIT/JPL facility which was established in Firestone to study the phenomenon of hypervelocity impact (2–10 km/s) as it relates to micro-meteoroid and space debris strikes on spacecraft and orbiting assets.
GALCIT reengages JPL in both teaching and research and launches a new graduate program in Space Engineering. GALCIT faculty and JPL engineers and scientists jointly engaged in curriculum design and teaching. The first GALCIT Master's class in Aerospace is admitted for the 2006–07 academic year.
John O. Dabiri (MS 2003, PhD 2005; student of Gharib) Assistant Professor of Aeronautics and Bioengineering, 2005–present. Experimentalist working at the intersection of fluid mechanics, biology, and bioinspired engineering design. Recent efforts have led to development of noninvasive methods to characterize the mechanics of propulsion in swimming and flying animals in situ. Research interests include unsteady fluid-structure interactions, small-scale underwater and aerial vehicles, geophysical fluid dynamics, and cardiovascular flows. Oversaw renovation of the Keck 40-Meter Flume, completed in 2007.
Dabiri, John Oluseun (2005) Unsteady fluid mechanics of starting-flow vortex generators with time-dependent boundary conditions. Dissertation (Ph.D.), California Institute of Technology.
Beverley McKeon, Assistant Professor of Aeronautics, 2006–present. Fluid mechanician with a focus on interdisciplinary approaches to the description and control of boundary layer flows. Her interests include the use of modern materials to provide novel surface actuation mechanisms including "morphing" surfaces capable of providing small geometric or morphological changes as a control input, non-normal mode amplification descriptions of turbulence, experimental measurements of canonical boundary layer flows at high Reynolds numbers and the accuracy of classical measurement techniques under these conditions.
Sandra M. Troian, Professor of Applied Physics, Aeronautics and Mechanical Engineering, 2006–present. Theoretical and experimental studies of micro/nanoscale transport phenomena in thin liquid films with applications to microfluidic devices, optofluidic sensing, and thin film lithography. Film patterning by thermocapillary, Marangoni and electrohydrodynamic stresses. Spear-headed the field of microfluidic devices based on free surface flows. Confinement effects which trigger instabilities and phase transitions in thin viscous films. Influence of non-normality on branching instabilities in spreading films. Commensurability and slip boundary conditions at liquid/solid interfaces. Evanescent wave sensing and trapping at liquid/solid interfaces.
Chiara Daraio, Assistant Professor of Aeronautics and Applied Physics, 2006–present. Her research interests reside at the interface of materials science, condensed matter physics, and solid mechanics, emphasizing in particular the highly nonlinear regime of wave propagation in solids. Her experimental work focuses on the design, development, and testing of multi-scale metamaterials and phononic crystals for use as tunable acoustic lenses and shock mitigating devices. Her work extends to the synthesis and assembly of nanomaterials and nanostructured systems and to their mechanical and electronic testing. Nanomaterials characterization includes also the study of carbon nanostructures found in sedimentary rocks to identify the oldest signatures of life preserved.
Jean-Lou Chameau becomes eighth President of Caltech.
Paul Dimotakis appointed JPL's Chief Technologist; succeeds Erik Antonsson, Professor of Mechanical Engineering.
Sergio Pellegrino Fellow of the Royal Academy of Engineering, Professor of Aeronautics and Civil Engineering, 2007–present. Studies of structural rigidity, with applications to prestressed mechanisms such as cable nets and tensegrity structures. Computations for statically and kinematically determinate/indeterminate structures. Research in deployable lightweight structures. New concepts for deployable space-based radar and antennas, retractable roofs, and multi-configuration structures. Self-deploying antennas made of ultra-thin composite materials that are folded elastically. Studies of deployment and stability of stratospheric balloons. Founder of Deployable Structures Laboratory (DSL) at University of Cambridge, 1990.
The Aerospace Historical Society is incorporated into GALCIT. The "International Wings of von Kármán Award" returns home.
Phase Two of the renovation of all GALCIT facilities commences in June. New laboratories and facilities include: the Laboratory for Large Space Structures, the Allen Puckett Laboratory of Computational Fluid Mechanics, the Gordon Cann Laboratory of Experimental Innovation, the Charyk Biomechanics Laboratory, and the new Karman Conference and GALCIT Archives room.
Fifty Years in Space GALCIT in collaboration with the Jet Propulsion Laboratory and Northrop Grumman celebrated the first 50 years of space technology by hosting Fifty Years in Space, an aerospace conference. It was attended by over 600 people and speakers included an international pantheon of space agency leaders, technologists, scientists, and politicians.