The Navy is hoping to one day run a huge chunk of its fleet on biofuels. So the Navy's advanced researchers – and their partners at the U.S. Department of Agriculture – are turning to a tiny robotic helicopter to help them figure out which crop they might be able to convert into their fuel of the future.

The experiment is taking place over 35,000 acres of Maui soil, on the fields of Hawaiian Commercial & Sugar, the state's largest commercial sugar plantation. That's the site of a $10 million, five-year gamble to test which of plantation's crops might work as grow-your-jetfuel. The drone helicopter will track every temperature fluctuation and sprouting bud emerging into the Hawaiian sun.But it's hardly certain that any of the plants will actually wind up in the engines of destroyers or F/A-18s. Yes, the Navy is betting big on alt-energy – the goal is to cut its fossil fuel usage in half by 2020. And yes, the Navy just made its biggest-ever purchase of biofuels: 450,000 gallons for $12 million, enough to power an entire aircraft carrier strike group during a demonstration voyage this summer. But half of that order went to a division of Tyson Foods, which coverts fats and waste greases into biofuels. The other half went to Solazyme, which uses algae as a means of fermenting everything from plant matter to municipal waste into fuel. In other words, neither of them is really grow-your-own.

Nevertheless, the Office of Naval Research and the Agriculture Department are wondering whether Maui's mix of plants, tropical sun, and nutrient-rich soil can produce a bumper crop of clean, renewable energy. Enter the Leptron corporation's tiny drone helicopter, the Avenger. It's about to be the Navy's robotic horticulturist in Hawaii.

The Department of Agriculture recently bought an Avenger – not to be confused with the next-generation Predator drone – so its thermal imaging cameras can gather "small plot specific data," particularly about crop temperature. The department wants a drone instead of a manned helicopter so it can keep the Avenger hovering over the patch of farmland and taking pictures longer than a human being could handle. The idea is that the Avenger's persistent stare will alert researchers to any problems with the crops – including jatropha, sweet sorghum, and sugar cane – before the entire experiment is jeopardized. The team figures that Hawaii is an ideal venue for the experiement: it's a high-fertility environment that's already home to the Pacific Fleet. "A perfect storm of opportunity," is how the Navy's top energy official described Hawaii in 2010.

In a way, Hawaii is a microcosm of the energy situation the Navy's in. For an archipelago in the middle of the Pacific, importing fuel means energy prices are sky high; but because of all its sunlight, warmth and high rainfalls, its ability to grow more crops per acre than most of the mainland U.S. raises the prospect of growing an energy solution. Hawaii also has one of the first biodiesel plants in the U.S., Pacific Biodiesel, which is much touted by the Department of Agriculture and the Navy and whose fuel powers the Navy's tour boats for the Pearl Harbor memorial.

If the Hawaii experiment – or, frankly, any of the Navy's biofuel experiments – go gangbusters, it won't just be sailors who benefit. Along with the Agriculture and Energy departments, the Navy will pump over half a billion dollars into the biofuels industry, with the hope of eventually driving down costs of renewable, green fuel that doesn't come from volatile global hotspots.

Still, the sugar-derived biofuel is only an experiment, not necessarily a harbinger of the Navy definitely planting fuel in the future. Industrial agriculture can actually require lots of money and, ironically, fossil fuels to produce. It's entirely possible that recycling greases or other waste-products will turn out to be cheaper and greener.

But the first lookout for whether grow-your-own fuel is even viable will be the diminutive, svelte Avenger, whose main rotor is merely six feet in diameter. In addition to optional remote-control or programmable autonomous flight options, it comes with a pair of video goggles, which Leptron calls a "Personal Media Viewer," to give a person below a drone's eye view. Watching the grass grow was never this captivating.