Allan J. Acosta

Richard L. and Dorothy M. Hayman Professor of Mechanical Engineering (Emeritus)
California Institute of Technology

1924 – 2020

This blog is written in celebration of Allan J. Acosta’s achievements as a technical leader, educator, and mentor for the entire community of engineers.


Even when it’s expected, the passing of a friend, colleague, mentor is never easy. When it’s your father, all the less so. But the kind words you have all shared here have been tremendous comfort to me and my family. They have helped us appreciate what we already knew – our father and grandfather was a very special person. It’s nearly impossible to reflect on a lifetime of memories in a short space. I beg your indulgence with a long piece.

For an average kid growing up in suburban LA, we had far from an average life. Back then, it was hard to get here from India, England, China, South Africa, Germany, Japan, and Ireland. The visitors that graced our house granted me a small degree of childhood prestige with my friends. Mom and Dad’s affection for his colleagues and students gave us great exposure to the broader world. Many of them, like Uncle Rolf (Sabersky), are no longer with us and like Dad live on in our hearts.

You enriched our lives from my earliest recollections. Good meals, wine and heated discussions were a staple in our home.  Dad adored spicy condiments which always graced our table, frequently gifts from colleagues. He had a near-competitive addiction to hot chilies of all kinds. Once, a Korean chef once refused to prepare his order, fearing Dad couldn’t handle it. The milder dish he was served was the hottest he ever ate.  

As in some of your stories, Dad encouraged me, scolded me (usually with due cause), always pushed me, and never held me back. Except once when I was about 10 he refused to let me ride the motorcycle one student had driven to the house.  (Dating was an entirely different matter.)

Before the sailboats we camped and hiked. Dad shared his love of walking with me.  Vigorously. No dilly dallying – walks are serious business and pity the person who couldn’t keep up with those long legs. With Dad’s coaching, I could name most native California tree species along with many flowers.

He was demanding.  But this stern man was also forgiving – after a terrible performance at a violin competition he gave me the perfect fatherly encouragement, and after several attempts at picking a career path he provided wise and loving counsel despite his personal vexation at my circuitous college career.

He was a loving grandfather to my 3 kids, giving them all special, cherished memories. He was a great story teller, they refused to go to sleep without one when we stayed with them. Years earlier, he composed a serial tale of Esmerelda, a princess who lived in the Icy Mountains, that entertained us as young kids during the long drives that summer we camped through Europe.

Dad also passed along his love of music, he had an amazing collection of recordings and loved playing his flute. He enjoyed the challenge of playing with many of you, and just a few years ago Dad, his brother Ed, Ed’s wife, and I gathered in Seal Beach to play quartets.

Then there were the sailboats. What halcyon days! The first was a Cal-20 named Release after the USS Release. Although Mom eschewed Dad’s competitive racing bug, they both loved cruising. The 20-foot boat quickly became too small and was replaced by the Santana 27.

Like most dads he taught me to ride a bike and drive a car. But he also taught me how to row a dingy, hoist a jib, reef a main, chart a course, sail through squalls, and swim through kelp without getting tangled up.

Dad and I hiked all over Catalina. Before the Nature Conservancy took over, buffalo roamed the entire island. Once we came face to face with a massive bull, but Dad calmly had us quietly back up before beating a hasty retreat. I rowed the dingy while he dove for abalone and sea urchins. Once, perhaps stoking my rebellious streak, he put his out of season abalone catch in a gunny sack and told me to throw it overboard if Fish and Game approached.

But I never imagined Dulcibella. Building her was in many ways one of Dad’s biggest projects. 4 years of his and Mom’s hard work just to launch, were followed by nearly 40 more years of pleasure which included living aboard, cruising, and just sitting at the dock.

Reflecting on Dad’s career and accomplishments I find I didn’t ask enough probing questions. To me he was Dad, the one who gave me a passion for hard work, loyalty, dedication, music, and the outdoors. I never did understand the joy in his eyes when he told me calculus would unlock the mysteries of the world. But in adulthood I found the gift of appreciation of the significance of his work and his worldview of science. A few years ago my husband asked Dad what the biggest scientific breakthrough of his lifetime was. Without any hesitation, he answered the transistor – because it made everything possible.

For me, your stories combine fond memories with details of his contributions to engineering. They confirm a life well-lived.  He is now in peace, but he did not go gentle into that good night – his ideas and spirit live on. Of all his interests and passions, one of his greatest joys was the deep and enduring friendships with his students and colleagues.

Sail on Dad.  

Re: Allan Acosta

Hello everyone:

Like all of you, I was saddened to learn of Allan’s death.  He taught me a great deal, probably much more than he realized, about research, fluid mechanics, writing, and thinking, all of it informally.  He was also kind, for he let me explore a topic neither of us knew anything about, namely, non-Newtonian fluid mechanics.  All of his guidance came to the fore when I wrote a manuscript based on my PhD research.  It was a good paper, as it turned out, and he helped with the writing, but he thought that his name did not belong on the manuscript, saying that the work was all mine. I explained how much I had learned from him, as indicated above, and how much he had contributed to the paper in that way.  Happily, his name is there.  

It was part of the academic culture in those days — the sixties —  that I had to persuade my adviser to be a co-author. 

David James

Re: Allan Acosta

It was a shock to hear of the passing of Allan; my friend, teacher and collaborator. While he had been ailing recently his passing leaves a deep sadness and it signifies the end of a very special era in my life. I met Allan on campus in 1960 when I arrived at Caltech as a foreign graduate student. He became my doctorate supervisor that year and that began a lifetime of camaraderie and friendship. Allan was unique in that he was able to slip transparently between being a teacher, a mentor and a friend thereby bridging the full spectrum of a close and enduring relationship. So many memories come to mind of this whether it was taking his classes, working with him in the lab, discussing some technical problem, critiquing my doctoral thesis, sailing or spending time with our families at his home in Altadena. He was always there to provide guidance, support and genuine personal interest. With great fondness, he always reminded me that I was his first doctoral student. I spent a couple of years after graduating as a Research Fellow working with him on several Navy and NASA contracts working in the Hydrodynamics laboratory in Guggenheim. We would spend many hours together on these programs but always go sailing on Wednesday afternoons in the “Wet Wednesday” racing series or race in some other regatta. Anchoring off Catalina on weekends to go scuba diving or fishing for abalone was another of his favorite past-times. 

Such life time recollections can never be replaced and will always be with me as i think of Allen. He changed my life and many others. To all his former students and colleagues and especially to his children Alison and Joey, who spent so much time with our family, and to Annette, our sincere condolences. We all will miss him!

Richard Wade

Re: Allan Acosta

Dear all,

I would like to join you mourning for Allan’s death. To me the new is inspiring deep sadness but also a feeling of serenity, as his has been a life of great accomplishments and recognitions by those who most closely knew him. Meeting Allan at Caltech 40 years ago when he became my supervisor was a very fortunate step in my life, since I ended up working with both a great teacher and a master of life. He has been a very special person to me for his enthusiasm and imagination and for his ability to motivate and direct a group that led research in his field worldwide for more than a generation. Allan always exercised the necessary leadership with wisdom, generosity, consideration and respect for the his younger collaborators. I owe him the “can do” attitude and the notion that “If everything seemed under control, you are just not going fast enough”, which hopefully inspired my later academic career. He once said that his objective in life was “trying to make things better”, the distinctive feature of a true gentleman. He fully succeeded. In retrospective, I was very happy and honored to realize that, while working with him, we had become friends, a friend I will never forget.


Luca d’Agostino

Re: Allan Acosta

Dear everybody

I am deeply sorry to hear Professor Allan Acosta’s passing away.  May he rest in peace.

I started the research of rocket pumps according to Allan Acosta’s proposal at Caltech in 1975.

I had gracefully appreciated his heartily appropriate advice and guidance in both USA and Japan.

He has been also my great senior and mentor for these 50 years.

Please convey my sincere condolences to his family.

Kenjiro Kamijo

Re: Allan Acosta

Hi All:

I concur with everything everyone has said about Al.  He was a great educator, mentor, friend and gentleman.  I had the pleasure and honor not only to have studied under him but worked closely along side him for more than a decade when he was consulting with the company where I was employed. He definitely had a positive influence on me and the other engineers who had the privilege of interfacing with him.  My wife and I have many fond  memories of having Pat and Al over to our home for social functions.  He will be sadly missed but not forgotten.

All the best,

Khoon Ooi

Kean Khoon Ooi

To Allan my mentor and friend

I joined Caltech in 1986. Having just landed from a flight from France, I recall the unsettling feeling of finding my marks in a place and city I had never been to. Just a day after I arrived Allan called me into his office, introducing himself with a warm smile and such a laid back open attitude that I instantly knew this was a man I could count on whenever I needed help. My PhD journey at Caltech would be ok… little did I know that Allan’s watchful presence would extend much beyond my PhD.

As a good mentor Allan knew when pushing for excellence was needed. During my first year of discovering the good side of Californian life I vividly recall being called to his office one day to be told “I did not bring you all the way from France for you to get a B in that electronics class”, and a small voice in my head telling me “I did not move all the way from France to be reprimanded by that professor”. My respect for Allan and the fatherly authority which emanated from him was enough to ensure that this single short burst of reprimand was the only recalibration that was ever needed towards the successful completion of my studies.

Allan of course had a passion for sea and sailing that pushed him to commute day after day 50 miles each way at very odd hours through the hellish LA traffic. It did take a few years for him to assess that I was far enough on my way to success, to finally ask me to go sailing with him to Catalina together with my girlfriend (now my wife Anh). I recall the first time I stepped on his boat asking basic questions about rigging and sensing the pride he had in explaining the some of the intricate details of the workmanship and construction process which took him many years to complete. What a fantastic demonstration of following through one’s dream! While mooring in Catalina Island’s Emerald bay sharing and tasting whiskeys, Allan related the story of what led him to build this boat and his long life dream to sail it around the world. Flashing a book with worn out pages one sees on manuscripts read and re-read hundreds of times, he narrated the story of this young man from Britany, France who had preceded him in the sixties: building that exact model boat while living in a camper car, and then setting off to worldwide adventures making friends and discovering different cultures. This book guided him, and is a great reflection of his never-ending eagerness to make meaningful friendships everywhere he went (even if his sailboat hardly ever sailed beyond Catalina). I thereafter sometimes wondered if my own Britany origins and love for sea played a part in my being selected to study at Caltech! For sure him bringing me to California had a defining impact on my life… I owe him, and Chris Brennen big time.

Through the years following my PhD there were several opportunities for us to catch up again, witnessing him being honored on multiple occasions, the pain of losing Pat, the joy of finding Annette, and whenever practical squeezing in a sailing trip to Catalina… Every time I travel through or set foot in LA I am instantly reminded of the nearby presence of my Californian father. Allan has taught me how to balance friendship and work, to follow one’s dreams with the hard realities of responsibilities that comes with being a family man. He was curious about everything, down to microdetailed technical understanding. Every time I would update him about a facet of my job he would never be contempt with the superficial and stubbornly drilled deeper until he would either run out of questions but mainly run me out of answers.

This morning, as I stand dumbfounded about the news of his passing away, I cannot help but to be profoundly sad… and happy knowing we will one day meet again and set off sailing amongst the breezy white clouds of eternity.

Yan Kuhn de Chizelle – May 2020