Ralph Dace Kimberlin, Ph.D. of Winter Haven, Florida, respected experimental test pilot, engineer, and graduate professor, passed away on November 28, 2024. He was 84.
Ralph was born on January 6, 1940, to Hazel Marie (Dace) and Clyde Eugene Kimberlin in Sullivan, Missouri. Ralph was the first of five children, known to family as RD. He grew up in the Missouri area of Anthonies Mill in the aftermath of the Great Depression.
Ralph discovered his passion at age seven, when a relative arranged a plane ride for him and his father. Taking off from an alfalfa field in a Piper PA-12, Ralph looked down at the houses in the countryside and knew that he wanted to fly airplanes for the rest of his life.
And fly he did. Ralph became an experimental test pilot and aerospace engineer. In his lifetime, he logged 9,300+ hours as a pilot across 250 types of aircraft, with 2,250 hours on certification projects that involved 25 “first flights.” Ralph worked during a flourishing period in aviation when new aircraft were being developed and built. As an FAA-designated test pilot and flight analyst, Ralph pioneered a large number of the general aviation aircraft in use today.
He graduated from the US Naval Academy in 1963 and was commissioned as an officer in the US Air Force. He did pilot training at Moody Air Force Base (AFB), achieving his first solo in a Cessna T-37. In 1964 at Eglin AFB, he was one of three officers testing weapons systems that included the AC-47 Gunship. This work led Ralph to combat evaluations of the aircraft in Vietnam. He also helped design engineer the AC-130 Gunship, recently used by the US in Iraq and Afghanistan. Ralph moved into civilian life in 1967, but he served in the US Air Force Reserves for more than thirty years, retiring in 2000 as a colonel.
Testing the AC-47 in Vietnam was fortuitous for Ralph because he met his wife, “Jean” Pham Giang, in Saigon. Set up on a date by a fellow officer, Ralph said he fell in love with Jean at first sight. Their courtship spanned a few weeks and then continued over love letters until Jean emigrated and they married in Ft. Walton Beach, Florida, in 1965. They remained married for 58 years until Jean’s passing in 2023.
In his civilian career, Ralph worked for historic aircraft manufacturers including Cessna, Beech, Rockwell, and Piper. In 1974, Piper named him their chief of flight test and aerodynamics. In tandem, he earned a Master of Science in aerospace engineering from the University of Tennessee Space Institute (UTSI). He knew that his success as a test pilot was tantamount to his engineering knowledge. Working on the front lines of aircraft innovation was not without its risks, and as he had a wife and two small children, Ralph decided to pivot into academia at the end of the decade. He wrote about this decision in a memoir that Flying magazine recently excerpted.
Academia felt fitting to Ralph as his mother had been a teacher. He became a professor at UTSI in flight test engineering, establishing an academic program for a Master of Science in aviation systems. As chairman of the program a few years later, it included a flight research center, a hangar, and a dozen airplanes considered “flying classrooms,” a rarity at a university. Ralph collaborated with military, government, and civilian flight test programs, and he continued his own flight testing and research. The US Navy contracted him to test pilot the Ball-Bartoe Jetwing, the only blown-wing airplane in the world. It is now displayed at the Wings Over the Rockies Air & Space Museum.
Ralph also developed the prototype FAA Flight Test Pilot / Engineer Training Program that became mandatory for FAA personnel. Most notably, Ralph took great pride in his students. Thirteen of the world’s astronauts matriculated through his programs, including Scott Kelly, Chris Hadfield, and Barry “Butch” Wilmore, who is currently aboard the International Space Station, returning to Earth in February 2025.
In 1991, Ralph earned his Ph.D. in aerospace engineering from the Technical University of Aachen, Germany. Not knowing the language, Ralph taught himself using CDs and a private tutor in order to successfully defend his dissertation in German.
In 2003, the American Institute of Aeronautics and Astronautics published Ralph’s seminal book, Flight Testing of Fixed-Wing Aircraft. He had wanted to document some of what he had learned to help the next generation – and a majority in his industry will attest to its value. The book covers performance, stability, and control for propeller-driven and jet aircraft. A final section covers “hazardous flight tests,” including two tests that forced him to bail out of the aircraft. In 2010, in addition to worldwide distribution, his book was published in Chinese.
After 27 years at UTSI, Ralph retired as an emeritus professor, and alumni distinguished service professor in 2005.
In “retirement” Ralph worked as a consultant test pilot and flight analyst for 17 more years! Some of his projects included the Liberty XL2 development and certification flight tests; the Cessna 208B with hellfire missiles and laser-guided rockets for US Air Force Special Ops; and certification of the Embraer Phenom 300’s stabilized camera system positioned under the nose of the aircraft. This system made it possible to film the dramatic flight scenes of the box office smash Top Gun: Maverick.
In his final role beginning in 2012, Ralph joined the Florida Institute of Technology to help them develop a flight test engineering graduate program. He served as a part-time professor and test pilot instructor during his 12-year tenure.
Among Ralph’s numerous accolades, the FAA awarded him the Wright Brothers Master Pilot Award in 2022, for his 50+ years of outstanding contributions to aviation safety. In 2014, his peers in the Society of Experimental Test Pilots honored him with the distinction of Fellow, their recognition for exceptional test pilots who have made significant contributions to the aerospace industry. And after decades of service, the American Institute of Aeronautics and Astronautics appointed Ralph chairman emeritus of their global Flight Testing Technical Committee.
Ralph’s achievements are even more remarkable when you consider the adversity he faced: In his 30s, his mother and brother were killed; in his 50s, he survived pancreatic cancer; and in his 60s and 70s, he cared for his wife through her mental health challenges. In his 80s, he was her primary caregiver during her long spell in hospice, honoring her wishes to remain at home. Ralph found meaning through acts of service, and this extended to his charitable support of social justice and the alleviation of suffering.
Ralph’s test piloting work required enormous skill, knowledge, and grace under pressure, but he was known to be kind, funny, hard working, and incredibly humble. He was a survivor, and not just from cancer. One of his “near death” experiences occurred in a dive test when the tail of the aircraft came off at max speed! His close calls imbued in him a deep faith and spirituality, leading him to teach Sunday School, serve as a deacon, and volunteer on committees at his churches for decades.
At 84, Ralph had an active lifestyle still flying his aircraft, mentoring his students, and supporting his friends and colleagues. He championed his alma mater, the US Naval Academy, and he treasured opportunities to gather with his classmates for Navy football games and reunions. He also voraciously consumed news on current events and politics, and he loved to ride his bicycle daily. After all, staying fit was how he continued to pass his annual flying physicals! Ralph was at work on a second edition of his flight testing book, and a dozen chapters into writing his memoir about his flying career.
Outside of his test piloting, or perhaps because of it, Ralph was a sage counselor to his children across work and personal matters. His intellect, intuition, and understanding of people and human behavior will be terribly missed.
Ralph was preceded in death by his wife, Jean; his parents, Hazel and Clyde; and siblings, Judith and Michael. He is survived by his children, Charles “Tony” (Hadley) and Lisa; three grandchildren Jenna, Thomas, and Marissa; and his sister, Donna (Marcus) and brother, Tracy.
Memorial services will be held near his home in Lakeland, Florida, at Beacon Hill Fellowship, 220 West Beacon Road, Lakeland, Florida 33803, on March 8 at 1:30 p.m. with a reception following. An additional service will be held at the Naval Academy Chapel in Annapolis, Maryland, on February 6 at 10:30 a.m.