BATTERY-POWERED PLANE

Science & Technology
BATTERY-POWERED PLANE
World's First Manned Flight on Dry Cell Batteries (September 29, 2006)

The plane in flight (Matsushita Electric Industrial Co. )

A propeller aircraft took to the air while powered by nothing more than commercial dry-cell batteries this past July. The flight was the fruit of a joint project by Matsushita Electric Industrial Co. and undergraduates at the Tokyo Institute of Technology. The group successfully completed a test flight in which the plane stayed airborne for 59 seconds and traveled 391 meters, exceeding by more than 100 meters the distance flown by the Wright brothers in the world's first manned flight in 1903.

Fuel-less Flight
A team of students from Tokyo Institute of Technology with experience participating in human-powered flight machine contests created the propeller aircraft, which has a wingspan of 31 meters. Their design called for an extremely light body, and the plane weighs in at just 54 kilograms, including batteries. The test flight took place in July at Okegawa Airport in Saitama Prefecture in the presence of official Japan Aeronautic Association observers.

Piloted by a 53-kilogram student, the aircraft rose smoothly off the ground and remained in the air for nearly a minute, traveling at an altitude of around 5 meters. The plane landed safely after exceeding its goal of traveling 260 meters, the distance covered by the Wright brothers when they completed the world's first sustained flight with a gasoline engine. The JAA has recognized the flight as the world's first by an aircraft powered by commercial dry-cell batteries and is seeking official recognition from the Fédération Aéronautique Internationale.

Innovative Batteries
The aircraft was powered by 160 AA-size Panasonic Oxyride dry cell batteries, which went on sale in 2004 and were Matsushita's first brand-new battery type in 40 years. Through various improvements in materials, these new batteries are capable of higher sustained voltage and also last longer than conventional alkaline batteries. Compared to gasoline and other fuels, the high weight-to-energy ratio of batteries renders them inefficient as a power source for aircraft. The Oxyride batteries, however, overcome that limitation. The plane's 160 batteries yielded 800 watts of power at takeoff, which is stronger than the takeoff power of human-powered aircraft that use pedals.

The successful team of students (Matsushita Electric Industrial Co.)

The student who piloted the aircraft said, "During the planning stage I wasn't sure that a battery-powered plane could actually fly. After several trial runs I grew more confident, though, and I'm relieved the flight succeeded." Matsushita Electric reports that, according to its designs, the plane is capable of flying a distance of 28 kilometers in around 30 minutes. The company also suggests that hybrid airplanes that utilize both battery and engine power are a possibility in the future.