Like many young boys, Farhan Gandhi too dreamt of being a pilot. "And then you realise you will be wearing glasses and that meant you cannot be a pilot," he says.

But he had no idea then, while studying at St Mary's High School in Mumbai, that he would still be connected to aviation. It was only after he got admission to IIT-Bombay, that he considered aerospace engineering.

It was a good choice. He went on to receive a bachelor's degree in aeronautical engineering from IIT in 1989. Currently a professor of aerospace engineering at Penn State, he was recently selected as a 2007 recipient of Popular Mechanics' Breakthrough Award for research done on rotors that increase in length as they move faster.

"I don't expect the invention to fly tomorrow, or the next year or one after that," he said. "The helicopter industry is very conservative. My concept is very radical and the risk involved in testing it is big. But surely we have started a discussion."

He expects the industry to try out his invention in unmanned aerial vehicles first. "They are omnipresent today," he said. "I expect the industry will take it to testing my invention there first and then on manned vehicles."

Dr Gandhi, who came to the University of Maryland, College Park, for graduate studies, obtained his Masters and PhD degrees in aerospace engineering, with specialisation in helicopters, and adaptive structures and materials. He joined the Aerospace Engineering faculty at Penn State seven years ago. He also serves as deputy director of the Penn State Vertical Lift Research Center of Excellence.

'Helicopter performance depends on the length of the rotor blades,' wrote Popular Mechanics in discussing Dr Gandhi's invention. 'For heavy lifting, a large rotor works best, but short blades reduce drag and ultimately allow for higher maximum speeds. Farhan Gandhi has devised an elegant, simple way to achieve both configurations in the same aircraft, using the same rotor.'

His idea involves having the outer half of the two-part rotor fit like a sleeve over the inner half. The two parts are held together by a spring at the far end of the inner part of the rotor. With increasing speed, the centrifugal force stretches the spring and the outer half slides out, increasing in an overall increase in length of the rotor.

A longer rotor results in more lift. When the rotors slow down, the reduced centrifugal force causes the spring to draw the outer half back in, thus reducing the overall length of the rotor. Gandhi told the publication, 'Instead of trying to muscle it with motors, we're exploiting the forces of nature and getting the work done for free.'

It is nothing unusual for IIT graduates to study abroad; many have joined private firms in America or started their own businesses. Dr Gandhi loves being in the academic world. "As to how I got here, I was very fortunate," he says. "My doctoral advisor, Inderjit Chopra, at the University of Maryland, was an outstanding mentor. He is himself a giant among academics and researchers in the field of helicopters, and he provided me with an environment in which I could flourish."

"Graduate studies is not about plugging numbers into equations, it is about learning how to attack engineering challenges," he says. "How do you get to the essence of a problem? How do you model and analyse the problem, and find solutions? I had this wonderful experience in graduate school and knew that this was the kind of environment I wanted to be in, for the rest of my career -- that's how I ended up in academia myself."

"Once you are seduced by the academic world, it is difficult to go into other businesses. Unless you are not good at what you are doing," he adds with a chuckle. "The really neat thing about being in academia is that unlike industry, where today's problems are being solved, we have the license to take on tomorrow's problems and challenges," he continues. "Work not so much on the nuts-and-bolts type engineering problems, but to dream big. To think of what can be! What if I could morph a helicopter? And then to try and actually make it happen."

At Penn State, he is also known for his individuality and passion for his work. "There are a lot of professors whose main focus is on trying to help industry solve their engineering problems," he muses. "Not so for me. If I do their jobs, what are they going to do? Rather, I'd like to work on problems and projects that they are not working on, certainly not in the near-term. I like to think out-of-the-box."

"To morph an aircraft, actuators are generally used. I like to think differently and ask if morphing can be accomplished without the cost and complexity and weight and power requirements associated with actuation. And I try to pass on this way of thinking, about graduate education, research, to my students. I have a group of 15 graduate students, mixture of MS and PhD students, from America, Korea, France [Images], India, and Turkey."