Frank Marble, 1918-2014: Tribute to an aerospace giant.

Frank Marble, among the nation’s preeminent aerospace propulsion scientists during the second half of the 20th century, has passed away at the age of 96. His pioneering technical contributions changed the direction of several important fields that are foundational to both aircraft and rocket systems. However, quite possibly, Frank Marble made even greater contributions to aerospace engineering through his gifted teaching and insightful training of legions of graduate students at the California Institute of Technology (Caltech), and through his serving as an example of true courage and loyalty during the McCarthy era and long afterward. Frank recounted his remarkable life experiences in a series of interviews conducted in 1994–1995 through Caltech’s Oral Histories Archive (1). And although, as a former graduate student and longtime friend of Frank’s, I had heard many of the stories recorded in these memoirs, there were many insights that I gained about the man, his contributions, and his experiences from reading the interview series. The reader is encouraged to access this marvelous resource for more information on this remarkable man. Frank was born in Cleveland, Ohio in 1918, and from a young age developed a passion for two things that remained with him throughout his life: airplanes and music. Ohio in the 1920s and 1930s was growing to become a rather significant player in the development of America’s burgeoning aviation industry. As a young boy, Frank used to take the streetcar regularly to the Cleveland Hopkins Airport, where he would wander into the hangars, look at the airplanes up close, and talk with the pilots and mechanics. This fascination set him on a lifelong journey of discovery with aircraft. Frank’s love affair with music also began at a young age, when he took up the trombone. He showed a great deal of talent, twice winning the state championship in trombone solo. Frank’s fascination with airplanes eventually won out over his musical focus, at least professionally. With financial assistance from his aunt and sister, Frank entered the Case School of Applied Science (now Case Western Reserve University) in Cleveland as a freshman, majoring in Mechanical Engineering. There Frank’s eyes were opened to the exciting world of aeronautics, the newly established field underlying the mechanics of flight. As Frank’s technical gifts and interests became evident, he dreamed of pursuing graduate studies at Caltech with the eminent fluid mechanician, Theodore von Karman. However, the outbreak of World War II altered Frank’s plans, at least for a time. He completed a Masters of Science degree at Case, and for most of the war worked at the newly established aero-propulsion laboratory in Cleveland, created by the National Advisory Council on Aeronautics (NACA); this was the predecessor of NASA’s Glenn Research Center at Lewis Field. As “Employee number 67” of the NACA Engine Research Lab, Frank was responsible for tackling a number of technological problems related to aircraft engines used in the war effort. Frank was able to solve engine cooling problems on the B-26 bomber (Martin Marauder) as well as the B-29 bomber (Superfortress). And although the propulsion systems for these bombers were of the air-cooled reciprocating/ radial type, Frank’s work at NACA also introduced him to gas turbine engine technologies, which showed promise for future air transportation systems. As Frank recounted, although the time he spent at NACA delayed the start of his doctorate studies, the experience changed the direction of his career and focus from aerodynamics to jet propulsion. After the war, Frank received a National Research Council predoctoral fellowship to study at Caltech, and he and his young wife, Ora Lee, headed to California in their “house trailer.” What started as a short stay for his doctorate turned into a lifelong association for the Marbles with Caltech and Pasadena, where Frank and Ora Lee raised their children,