WHAT'S DRIVING THE ROSEN BOYS?

Meet Harold Rosen, a slight, gentle-mannered 70-year-old Cal Tech Ph.D. who predates the space age by a dog's age. Yet every time you watch a live-television feed from distant parts of the earth, chances are the signal has bounced off one of the satellites he helped design for Hughes Aircraft in his 37-year career. "He is uncommonly brilliant," says his biggest fan, younger brother Ben, 63. "He's a national treasure."

Actually, a lot of people would say that about Ben. He has a way with numbers. As a five-year-old he could calculate complex mathematical progressions, and as a grownup he figured out that raw computing power was growing and the price dropping so quickly that one day every office and home in America would have a computer. With his partner L.J. Sevin, he helped launch Silicon Valley legends such as Lotus Development, Cypress Semiconductor, Borland International and an outfit called Compaq, the world's largest personal-computer maker. He's still chairman. "My brother has done pretty well for himself," says Harold with a smile. Little brother is worth about $100 million.

Logically speaking, if these two guys profess a view of something's being big in the future, it might be smart to pay attention. They do. That something is a newfangled, high-power, high-mileage, nonpolluting automobile engine that their company, Rosen Motors, plans to build and sell to automakers. "We see Rosen Motors as the capstone of our careers, the crowning achievement," says Ben.

The Rosen engine design, announced last week, draws its power from two very different sources. The first is a high-powered turbine--a mini-jet engine if you will--that will keep your car purring along on the freeway with just a spit of gas every now and then. For quick acceleration and hill climbing, the turbine is linked to a flywheel, an energy-producing and energy-storing contraption that is at least as old as the first potter's wheel--a stone that had to be heavy enough to continue turning between kicks from someone's foot. Flywheels were a prominent feature of the Industrial Revolution, delivering a smooth flow of power over the bumps and jerks made by an engine's piston strokes, and small flywheels perform that function in every car today.

Most of the auto companies and academics who have heard of this design think the Rosens are spinning their wheels. Of course, the auto companies thought the Japanese didn't have a clue either, but they've also invested billions of dollars in flywheel technology without coming up with much. Says Harold: "Detroit never took hybrids seriously. They weren't thinking broadly enough." Chrysler tried, and failed, to field a race car with a turbo-flywheel power train (the engine and transmission) a couple of years ago.

Yet every auto company in the world is desperately seeking an engine to replace the internal-combustion machine that has been powering cars, consuming oceans of fossil fuel and polluting the universe for about 100 years. GM, in fact, will begin selling a battery-powered electric car in California this year. California, locked in a perpetual automotive smog, requires that by 2003, 10% of the cars offered for sale in the state produce zero emissions; many states are expected to follow suit.

A handful of companies are working on advanced flywheel systems to power automobiles, buses and even trains. One company, U.S. Flywheel, is developing a car that uses a series of flywheels, with no gas engine at all. The flywheels would be recharged as batteries are. Rosen Motors will be first to the finish line, says Ben. "There are lots of others working on this. We think we will be there earlier and with better technology."

The flywheel in Rosen Motors' power train is something different altogether. It is a roughly 12-in. by 7-in. cylinder that hangs suspended in a vacuum from magnetic bearings and normally spins at 55,000 r.p.m.; today's cars run at an average of 2,000 r.p.m. The energy of the flywheel is stored in this rapid rotation, which generates electricity on demand. In the Rosens' power train, the flywheel works in conjunction with a gas-driven microturbine to make the car go.

The essence of the hybrid is that very little energy is wasted. Not only does the turbine re-spin the flywheel, but so does braking, which in today's cars produces energy that is lost. The same goes for fuel. With a catalytic "combustor" on the turbine that burns gas more efficiently, the power train will produce what is, by EPA standards, "zero emissions." According to the Rosens, the turbo-flywheel combination will at least double the gas mileage of the car in which it is used, produce a satisfying sound not unlike that of a Lear Jet (albeit far quieter), and push a Mercedes-Benz from 0 to 60 in a tidy six seconds flat, 0.6 seconds faster than Mercedes' own V-8 can do it.

The company expects to have a working prototype of this power train next year and even foresees limited sales to gotta-have car fanatics in 1998. But there is no way of knowing exactly how close they are to the multimillion-dollar and possibly multibillion-dollar payday that awaits them if the engine is mass produced. The hybrid works well in the lab, but the first road tests have been postponed until next year.

That's one reason many competitors in the race for a new engine remain exceedingly dubious. "I consider Rosen Motors to be a very small part of the overall flywheel effort," says Joe Beno, program manager for the electric-vehicle program at the University of Texas at Austin, whose group will put a flywheel motor in a commercial bus in Houston next year. Kevin M. Myles, director of the electrochemical technology program at Argonne National Laboratory, who has done extensive work with alternative-fuel vehicles, doesn't think the Rosens have addressed the safety problems inherent in flywheels. A wheel operating at such a high velocity can explode if knocked off-line--say by hitting a pothole--turning high-tech carbon fibers into shrapnel. "In the final analysis, the design needs a lot of work on housing and containment. I don't think he has the ultimate power train. No disrespect intended. This is simply an observation that these guys with very limited funds are trying to do what Detroit did over decades." Chrysler's flywheel failure mirrors these concerns.

The Rosens instead plan to blow away the field in part because Harold and his team of engineers have solved a set of daunting technological issues just in the past year. Harold is, after all, a rocket scientist. For instance, he has been able to create and sustain a relatively pure vacuum in which the flywheel spins, using such exotic devices as molecular drag pumps and molecular sieves. A better vacuum means less friction, thus better spin. He also has been able to suspend the rapidly spinning flywheel in its unstable environment by using sophisticated gimbals and magnetic bearings--something very few, if any, other scientists are thought to have accomplished. "Doing the magnetic bearings with those particular dynamics was a daunting task," says Harold. "You have to be able to hit a deep pothole and still make it work." That's a clue that the brothers are well on their way to solving safety problems.

By the end of the year, the Rosens will have spent $13 million on their project. They expect to spend an additional $10 million to $15 million next year, nearly all of it from Ben's silicon-lined pockets. They also plan to begin selling their flywheel to utilities for stationary power generation next year. Says Ben: "By the end of next year, we will have generated enough risk reduction to seek external funding." Eventually they plan to sell shares to the public. They want to build their own plants to make their own power trains and sell them to car companies. In their vision, "Powered by Rosen" would become a cachet, like "Intel Inside."

This is not a vision that anyone in Detroit shares. Instead, the industry is working closely with Rosen competitors like U.S. Flywheel, Trinity Flywheel and Unique Mobility. That's a badge of honor to Harold and Ben, who are clearly thrilled to be working together. When they were younger, Ben was very much the little brother walking devotedly in the older brother's footsteps: he followed Harold to Cal Tech, and then to Raytheon Corp. in the 1950s, when Ben got his very first job working for his brother, building missiles. Their paths diverged when Ben went East to get an M.B.A. and Harold started building satellites on the Coast. For years they kept up a bicoastal relationship, says Ben, "the way families that live far apart usually see each other, on occasional visits." Now, after 40 years, they see each other all the time. Yet why, after such extraordinary careers, do they need the headache of a high-tech start-up? "We both like tilting against giants," says Ben. "When Harold started his satellite program at Hughes, he was going against AT&T.; In the personal-computer business, I was up against IBM and other giants." The giants ignored them, and paid the price. The Rosens have this idea that history just might repeat itself.