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7/15/2020 A Tribute: Satish Dhawan (1920-2002) – A Quarterly Publication of ACCS
to the United States. There, at the University of Minnesota, he earned an MS in aeronautical engineering in
1947, and from California Institute of Technology (Caltech) he earned the Engineer’s degree in 1949 in
aeronautics and a PhD in aeronautics and mathematics in 1951. His PhD advisor was the renowned
professor Hans W. Liepmann who along with Anatol Roshko (also at Caltech) wrote a classic textbook,
Elements of Gas Dynamics, in 1957.

Dhawan’s Caltech years gave him the breadth of scholarship, depth of research and an opportunity to
hone his skills in investigating problems independently and e ciently. From this point onwards his
professional career would be stamped with these rare qualities from which others like Abdul Kalam would
bene t in their early professional years and into the future. Dhawan’s Engineer’s and PhD theses,
respectively, were

Dhawan, Satish. Engineer’s thesis, On the design and use of a exible nozzle for the Galcit transonic tunnel.
California Institute of Technology, June 1949.[2]
Dhawan, Satish. Direct measurements of skin friction. Dissertation (Ph.D.), California Institute of
Technology, 1951.[3]
Taken together the scienti c output was very signi cant as they produced some pioneering work on
boundary layer ows in uids. Liepmann and his two students Roshko, and Dhawan worked together and
demonstrated the importance of the state of the boundary layer, laminar vs. turbulent, on resulting shock-
wave pattern and pressure distribution. This was Dhawan’s rst participation in active research.[4] This
classic work is elegantly presented in NACA Report No. 1100 published in 1952.[5] The trio worked and got
along so well that it “laid the foundation” for their lasting friendship over the next half century. Following
this work, Dhawan started his PhD work on the direct measurement of skin friction.[6]

In his PhD thesis, Dhawan showed great ingenuity in developing a device to measure local skin friction on a
at plate by measuring the force exerted upon a minute movable part of the plate by means of a reactance
device. The device was then used to make accurate measurements in the low speed range, both for
laminar and turbulent boundary layers and then in the high speed subsonic range in turbulent boundary
layers. Finally, some measurements were made in supersonic ow. Those were the days when wave drag
and induced drag experienced by a body moving through a uid were much better understood than skin
friction and boundary layer whether in theory or in experiment. A much better understanding was critically
needed to design high speed aircraft (e.g., ghters) and missiles. The research done was a great success
and Dhawan’s stature as an outstanding researcher was established. His PhD thesis (with minor editorial
changes) also appeared as a NACA Report in 1953.[7]

In addition, Dhawan and Roshko collaborated on the design and construction of an ingenious exible
nozzle for conducting research in supersonic ows. At Caltech, Dhawan’s entire time was spent at the
Graduate Aerospace Laboratories of the California Institute of Technology (GALCIT); its rst director was
the Hungarian aerospace genius Theodore von Kármán (1881–1963) from 1930 to 1949.

In 1951 Dhawan returned to India and joined the Indian Institute of Science (IISc) as a scienti c o cer. In
1955, he became a professor and head of the Department of Aeronautical Engineering succeeding (O.G.
Tietjens, 1948 – 1955) and, in 1963, was appointed director of the institute (succeeding Suri Bhagavantam,
1957–1962), a position he occupied till 1981. Throughout his career, the in uence of Caltech and Liepmann
is highly visible. In scope and aim, he clearly wanted to emulate GALCIT. As Liepmann wrote about his
association with Dhawan: “Ever since then, we in GALCIT have had close contacts with the Indian Institute
of Science, and thus a calibration station for admission, leading to some excellent Indian graduate students
at GALCIT.”[8]
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