eMission control – Focus: Airways

Global air travel is not receding. In fact, in several places triple-digit percentage increases are not uncommon.

Katherine Rowland in OnEarth magazine in “Infographic: Flying the Friendlier Skies,” writes: “In emerging economies, the growth has been dramatic: between 2007 and 2010, passenger volume in China increased by almost 50 percent — another 84 million fliers. In a number of smaller countries, growth has been even more rapid, with passenger numbers doubling in the Philippines, Turkey, and Vietnam; tripling in Ukraine; quadrupling in Hungary.”

Rowland also cites the National Aeronautics and Space Administration (NASA) in stating that four percent of the world’s greenhouse gas (GHG) emissions are attributable to flight. And in the U.S. alone, jet fuel to the tune of nearly 20 billion yearly gallons is burned. And scaling back the number of flights “isn’t likely to happen,” the OnEarth writer surmised.

On the surface (and above it), in the grand scheme of things, aviation produces but a scant four percent of global GHG emissions overall. That means the remaining 96 percent comes from elsewhere. But the downside is if the number of flights continues to increase, GHG emissions from aviation will also go up. Unless …

NASA's Helios unmanned aerial vehicle
NASA’s Helios unmanned aerial vehicle

Solar cells, fuel cells and more

Jet fuels that burn more cleanly than that which is commonly used today is one answer to help reduce aviation’s carbon footprint. Another would be a reconfiguration of travel patterns; that is, fewer numbers of fliers taking to the skies with more opting to travel via high-speed train for example for intermediate-distance trips – or trip lengths from between 100 and 500 miles, in other words. Radical new designs in aircraft, meanwhile, would be yet another.

With regard to the last, Nancy Atkinson at Universe Today in “Solar-Powered Airplane Makes First Intercontinental Round-trip Flight,” on July 24, 2012 writes: “A unique airplane has just completed a 6,000 km journey, making the first solar-powered intercontinental round-trip air journey.”

Called the Solar Impulse, the aircraft made the historic flight between Africa and Europe and covered a distance of 4,000 miles (6,000 kilometers).

“The trip began two months ago, on May 24 and so was not a test to see how fast it could make the trip, but to assess the endurance and reliability of the craft, as well as bringing awareness to more people of energy issues,” writes Atkinson.

A unique Solar Impulse feature is the solar cells – which enable the plane to fly – are built right into the aircraft’s wings. According to Atkinson, the wings are 193 feet (64.3 meters) in length and accommodate 12,000 photovoltaic cells, the plane itself weighing 3,500 pounds (1,600 kilograms). A light flight, for sure!

Meanwhile, light from the sun collected by the cells is converted into electricity which, in this case, supplied energy to four electric motors.

Bertrand Piccard and André Borschberg took turns piloting the craft. Flying was done predominantly during daylight hours, although the plane has flown at night in the past as I understand it.

So what’s in store? A ‘round-the-world trip? Stay tuned.

Other experimental electric solar- and fuel-cell-powered aircraft include the Pathfinder, Pathfinder Plus, Centurion and Helios from NASA.

In the meantime, look for more aviation breakthroughs to help lower greenhouse gas and other emissions coming from that sector.

Image above: NASA

– Alan Kandel