HENRY MCDONALD (1937-2021)

BY JAYANT S. SABNIS AND DANIEL S. GOLDIN

HENRY MCDONALD, a pioneer in the development of computational fluid dynamics methods and their applications in the analysis of engineering problems, and an engineering leader, died peacefully on May 25, 2021, surrounded by his family.

Harry was born in Glasgow, Scotland, on Jan. 24, 1937, to Alfred and Margaret McDonald and grew up in the small town of Girvan, Scotland, where he spent hours watching Royal Air Force planes taking off and landing, as well as building model planes. Harry studied aeronautical engineering at the University of Glasgow and trained as a pilot with the Royal Air Force Universities of Glasgow and Strathclyde Air Squadron. Harry worked in the U.K. aerospace industry on several civil and military aircraft before emigrating to the United States in 1965 with his wife June Seaton McDonald, M.D.

In the U.S., he joined a corporate research laboratory, United Technologies Research Center (UTRC) in East Hartford, Connecticut, as a staff member, rising to become head of the Gas Dynamics Group in 1973. At UTRC, Harry concentrated on experimental and analytical and computational investigations of heat transfer and fluid dynamics applied to turbomachinery flows. He was ahead of his time in the development of computational techniques in this field. While the conventional approach in the use of computational techniques consisted of making extensive measurements and using the data to develop empirical correlations for use in the design process, Harry was a strong proponent of developing physics-based models that could be validated using experimental data to continuously reduce the level of empiricism in codes developed for aerothermal analyses for aircraft engine components. Computer codes based upon these were extensively used in airfoil designs at Pratt & Whitney (P&W) and have influenced the aerodynamic designs of several P&W engines. Harry’s approach to the use of computational methods was well aligned with a Richard Hamming (NAE 1980) quote observed by one of the authors (J.S.) in Harry’s office: “The purpose of computing is insight, not numbers.”

Harry’s work also included leading the development of computational techniques for the solution of Navier-Stokes equations, a field that eventually became known as computational fluid dynamics. Harry, working with his longtime colleague W. Roger Briley, pioneered the Linearized Block Implicit (LBI) algorithm, which made it possible to obtain numerical solutions to systems of nonlinear, multidimensional, partial differential equations in a computationally efficient manner. This implicit finite-difference method for the multidimensional Navier-Stokes equations made it possible to exploit the favorable stability properties of implicit methods and thereby increase computational efficiency by taking large time steps. The method consists of a generalized implicit scheme that has been linearized by Taylor expansion about the solution at the known time level to produce a set of coupled linear difference equations that are valid for a given time step. The LBI algorithm was a field-leading accomplishment that enabled flow field simulations with high near-wall (viscous sublayer) resolution, thereby eliminating the use of empirical correlations in form of wall functions. This accomplishment was a key contributor to the development of the field of computational fluid dynamics.

Harry also led the development and demonstration of an unsteady Navier-Stokes code to compute the motion of a maneuvering submarine, including a rotating propeller. This code reduces the use of empirical approximations in the prediction of submarine maneuvering characteristics, thereby reducing scale-up problems.

In 1976 Harry left UTRC to start Scientific Research Associates Inc. (SRA), a research and development company in Glastonbury, Connecticut. He provided leadership to a group of highly qualified engineers and scientists who specialized in fluid dynamics, optical electronics, and biomedical research. Harry was an outstanding mentor and role model for these researchers working on the cutting edge of research in their fields. He nurtured their professional growth by giving them coaching and responsibility in their assignments, as well as providing critical yet supporting assessment as needed. Many members of this group of engineers have gone on to become recognized leaders in their respective fields.

Harry always welcomed new professional challenges and was energized by them. He also found ways to pass on this unique characteristic to those whom he mentored. He frequently nudged them to take on newer challenges and often knew that they were ready for such responsibility before the individuals knew it themselves.

Harry also actively participated in Connecticut’s high-technology economic development policy. Under his leadership, SRA was awarded the Governor’s Innovation Award acknowledging its economic development contributions to the state of Connecticut. At SRA, Harry was co-inventor of a novel high-frequency jet ventilator, which provides life support to patients critically ill with Adult Respiratory Distress Syndrome. He was awarded the Small Businessman of the Year Award for High-Technology by the state of Connecticut for this achievement.

Harry held academic positions at Pennsylvania State University and Mississippi State before accepting an appointment as director of NASA Ames Research Center in 1996. His specific mandate from the NASA Administrator Daniel S. Goldin (NAE 1998) was to “significantly improve America’s capability in the field of computational fluid dynamics and help the about 5000 people working at the Center see a future that made Ames a driving force within NASA and as a supporter of partner federal agencies to advance our nations technical leadership.” Harry delivered and provided exceptional leadership and technical insight helping the center reinvent itself in the late 1990s. He secured the lead NASA center role for Ames in astrobiology, air traffic management, information technology, and nanotechnology. He went on to recruit Nobel laureate Dr. Baruch Blumberg (NAM 1982; NAS 1975) as the inaugural director of the NASA Astrobiology Institute, a virtual organization composed of NASA centers, universities, and others dedicated to studying the origin, evolution, distribution, and destiny of life in the universe. Under Harry’s inspirational and dynamic leadership, the NASA Ames Kepler Team developed the key technologies necessary to win a Discovery Spacecraft Award in 2001. This event led to the development, launch, and in-space operation of the most important exoplanet finding missions to date. Harry also initiated the University Affiliated Research Center and the NASA Research Park, which created flourishing partnerships of enduring strategic importance to the NASA Ames Research Center.

Throughout his career, Harry was engaged in several investigations of failures in aerospace systems. In 1986, he was asked to assist the NASA team investigating the Challenger disaster. In 1999, Joseph Rothenberg, the associate administrator for space flight, appointed Harry to lead the Space Shuttle Independent Assessment Team, an independent technical team to review the space shuttle systems and maintenance practices. In addition, Harry led an independent investigation of a V-22 Osprey accident as chair of the Tiltrotor Aeromechanical Phenomena Assessment Panel, reporting safety- and stability-related recommendations to the assistant secretary of defense. He was also a member of the Lockheed Martin team investigating the failure of a solid rocket booster that was a part of the Titan IV rocket.

Harry was elected to the National Academy of Engineering in 2000. He was a fellow of the Royal Academy of Engineering, an honorary member of the American Society of Mechanical Engineers, a fellow of the Royal Aeronautical Society (RAeS), and an honorary fellow of the American Institute of Aeronautics and Astronautics.

Harry received the Gold Medal Award from the RAeS in 2009 for work of an outstanding nature in aerospace. Harry was awarded the NASA Distinguished Service Medal, NASA’s highest award, in 2000. In 2009, he was inducted into the NASA Ames Hall of Fame for providing “exceptional leadership and keen technical insight to NASA Ames as the Center reinvented itself in the late 1990s.”

Harry was an exceptionally strong mentor. He had an outstanding ability to assess the capabilities and development needs of his team members. He provided excellent support when it was needed, timely and quantitative critique when it was warranted, and built strong long-term bonds with the individuals who interacted with him. Those who were privileged to have Harry as a role model now have a way to think about leadership through reflecting on, and answering, the question “what would Harry do in this situation?” on their own.

Those of us who were privileged to have Harry as a mentor will miss his well-thought-out counsel. Those who worked with Harry as a colleague will miss an excellent sounding board. All will miss Harry as a uniquely interesting human being for his warm and charming demeanor, and his (almost impish) laughter.

In 2021, the Henry McDonald Memorial Fund was established to support engineering education at the University of Glasglow. Awards are given to “underprivileged and exceptional engineering students at the university to help eliminate barriers facing Scotland’s best and brightest.”

Harry is survived by his beloved wife, June Seaton McDonald; his loving children, Ian McDonald, Catriona Harrop, and Gordon McDonald; his nine grandchildren; and fondly remembered as a loving father-in-law by Patricia McDonald, Daniel Harrop, and Alison McDonald.