MOULTRIE — Continuing Colquitt County High School’s long-standing tradition of impressive showings at regional science fairs, four local students will advance to state competition, two to international competition and two to the national symposium.

Winning first place at the 36th Annual Darton College Regional Science and Engineering Fair recently are Arturo Arenas, Cole Perry, Lauren Cameron and Lena Griffin.

This year, Arenas, 17, a senior, took his project from last year to new heights by polishing his design of a hovercraft. This year, he replaced a water hose with rubber tubing for the perimeter of the disc-like craft to serve as a frame for the plastic interior. The rubber tubing was stronger than the plastic hose, he said. Also, he redesigned tubing on top of the craft to allow more air to pass from the top to the underside.

Arenas modified the hovercraft’s gyroscope, a bicycle wheel, by affixing it to a handheld drill. He was able to modify his craft to negotiate tighter turns.

He won grand prize in physical science and will advance to the International Science and Engineering Fair in Atlanta in May and the national symposium in Orlando later this month. His project also won the Woodrow Wilson Engineering Award at the regional fair.

Fifteen-year-old sophomore Perry’s analysis of cotton’s water consumption won him the grand prize in life science and a spot in the international competition.

Perry watered cotton in differing amounts and at different stages of development and found that watering later in the growing season would produce a higher yield, specifically three weeks after the first flower appears.

“Georgia had the biggest drought we’ve ever had, and this would save the farmers money and water,” Perry said.

Perry’s uncle is a farmer, and he was advised by Glen Ritchie of the University of Georgia Department of Crop and Soil Sciences. His project also won the attention of Regions Bank and an award from the U.S. Navy and Marine Corps.

Cameron, 16, a junior, manufactured biodiesel from soybean oil and ran it through a battery of tests up against petroleum diesel. He compared lubricity in endurance and strength, viscosity, cloud point, gel point and flash point in the fuels performances in a simple engine.

The biodiesel worked better in all aspects except for cloud and gel point and viscosity. More attention has to be paid to storage of biodiesel, especially in cold climates, he said.

“It takes a lot more heat for biodiesel to actually catch on fire, which is safer for storage,” he said.

But Cameron was most impressed by his biodiesel’s performance in lubricity to preserve the life and function of an engine.

“Biodiesel performed way better,” he said. “... Biofuel is such a good lubricant it’ll actually clean out your engine. That’s why you have to change your fuel filters.”

Cameron learned how to make biodiesel locally from online biofuel consultant Tommy Greene and Kathy Baker of T-Co Alternative Fuels.