I am a research scientist in the Fluid Mechanics Laboratory at NASA Ames Research Center. My background is in experimental research of fluid flows as applied to the field of aeronautics --- this subject is popularly known as aerodynamics. Two interests that I developed during my college days are in wind tunnel design and sports ball aerodynamics. I did all my schooling in England. My undergraduate degree was in aeronautical engineering after which I went to graduate school at Imperial College in London where I specialized in fluid mechanics with emphasis on turbulence (yes, the same stuff you often experience on airplanes). My Ph.D. thesis was on the study of flow through the various components of a small low-speed wind tunnel (the kind that lots of schools now want to construct).

I have also helped with various projects here at Ames including the 12' wind tunnel renovation project and testing for a new National Wind Tunnel Complex which was proposed a few years ago, but was canceled last year. I have written articles which give "design rules" for small low-speed wind tunnels. As an offshoot, during the last couple of years I was at Imperial College, we started doing some wind tunnel research on cricket ball aerodynamics --- basically, a study of why a cricket ball curves through the air (much like a curveball in baseball) and what parameters can affect its flight. That is how I got started in this exciting field. After I moved to California, I also looked at the aerodynamics of baseballs and golf balls and I have recently become involved in a project on tennis balls. I am familiar with all kinds of sports balls and their aerodynamics and I have written several articles on the subject. Currently, I am writing a book on "The Aerodynamics of a Cricket Ball."

My Career Journey

I was born in Nairobi, Kenya, which lies on the east coast of Africa. I went to high school and beyond in England. I came to NASA as a National Research Council Post-Doctoral Fellow in 1981 after which I stayed on as a contractor through Stanford University. In December of last year I was hired by Ames as a Senior Research Scientist. The person who influenced me the most towards where I am today is my graduate advisor, Peter Bradshaw, who is now at Stanford.

Currently I am involved in research on a relatively new measurement technique which uses special paints to measure pressures on a model surface. The surface pressures are extremely important because they give the lift and drag forces on the model and they can also indicate design problems. The paint is excited by a special light source, and by measuring the intensity of the emitted light, we can determine the pressures on the model. High grade scientific CCD cameras are used to image the surface and the data are then processed on work stations. This technique will hopefully soon replace the old technique which consists of drilling tiny little holes on the model and then connecting them to pressure transducers, a procedure which is very time consuming and costly. The paint seems to work better at very high speeds (transonic to supersonic), but we are currently researching low-speed applications as well. The development and research of the pressure sensitive paint technique is typically done in the smaller wind tunnels, while the applications are tested in the bigger production tunnels such as the 12' and 11' complexes.

Career Likes and Dislikes

The main positive part is that in a research career you can work independently and there is the opportunity of doing what you want. You come up with new ideas or new ventures, and within reason, you can pursue them. I have been lucky enough to be able to do that for most of my research life. There is the sense of a challenge to uncover something that has not been uncovered before. Also, I love the fact that we do not have to dress up (in suits) every day. The main concern is that there is not enough research funding nowadays. NASA has been suffering from a constantly decreasing budget and, in my opinion, the aeronautics side of research has suffered more than its fair share. My main worry is that we will be unable to draw young researchers as a result which does not bode well for the future.

The Early Years

At the risk of sounding corny, I have loved planes since I was a little kid. My interest was maintained partly by looking at books and partly by going to the Nairobi airport to watch planes take-off and land. Like many small boys, my real dream was to become a commercial airline pilot. However, once I joined the Royal Air Force as a reserve (while I was in college) I soon realized that the only fun-flying was in fact as an air force pilot and that commercial flying would be awfully boring (worse than driving a bus!). The thought of leading a regimented life in the armed forces, however, did not appeal to me and I decided to pursue a career in aeronautics research.

Advice

Nowadays, there are a lot of opportunities for early learning in this field. A great way to start is by browsing on the Internet --- just like you are right now! Another thing kids can do is go to science and aeronautics museums. The Exploratorium in San Francisco has some excellent fluid flow exhibits, and I just recently visited a super aeronautics museum in Seattle, where Boeing resides. Building and flying model airplanes is also a great way to get an introduction to aerodynamics while having lots of fun at the same time. Concentrating on math and science while in school will help enormously in any engineering related career.

Personal Information

I have a wonderful wife, Beena, who is a laboratory technologist (yes, the medical person with a needle that kids are not too fond of) and she works at a lab in Mountain View. We have a 14-year-old son (Shalin) we are extremely proud of. Shalin just started high school and he loves to play ice hockey and golf --- unfortunately, he did not take a liking to cricket, a sport I played for most of my life. He also likes to listen to funky music (or more like noise, in my opinion) and plays the saxophone in the school symphonic band. We all love to watch sports, especially NFL football --- who wouldn't with a team like the 49ers in the area. We also like to go camping and hiking. I don't play cricket any more, but I found the closest sport, softball, which I now play regularly. I also enjoy playing golf, but I wish my game was more consistent, just like millions of other weekend golfers!

Archived QuestChats with Rabi Mehta

• January 26, 1999
• April 2, 1998