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A wide array of of solar planes are flying in the sky

EDITORS NOTE: Don Lee is taking a break from his column this week. The following is a piece that originally was published on May 14, 2017:

In addition to the Solar Impulse, there are other solar-powered planes in the news.
The Aero Electric Aircraft Company’s Sun Flyer, which the inventors envision as a trainer for student pilots, would be able to stay in the air for three hours.
They have great hopes for it of course. They hope to have prototype flying before the year ends. The company claims that the fuel cost will be $1 per hour.
With aviation gas at $5.60 a gallon, and assuming a Cessna 172 consumes eightgallons per hour, that fuel cost for the Cessna trainer would be $44.80 per hour. They hope to achieve this great efficiency by using lithium batteries and adding power from solar cells mounted on top of the wings.
These solar cells will fully charge the batteries if it is parked outside for a couple of days. The claim is that these cells will provide 15 percent of the power while flying. Another claim is to recover power from the propeller while descending.
The electric motor will become a generator when descending. They plan to recover another 15 percent from it. The electric motor/generator driving the propeller is the size of a stack of pancakes.
The projected price of the Sun Flyer is $200,000. The company anticipates a shortage of pilots since the Air Force doesn’t graduate as many as it has in the past. I have also read the F-35 fighter airplane will be the last pilot-flown fighter.
With the advent of advanced drones, the demise of the fighter seems probable. The drones can be designed to withstand G forces that would incapacitate a human pilot. Humans would not be a risk also.
Until I visited the Experiment Aircraft Association convention in Oshkosh, Wisconsin, I didn’t realize there were so many solar-powered planes that are flying. Upon further exploration on the Internet, I found a whole bevy of solar planes that are flying.
I’ll mention a few others that seem viable.
The SunSeeker II has flown over the Alps and toured the European Continent in 2009. It is a single place plane but they have a two-place plane named Sunseeker Duo, which is the first two-place solar plane. It has been flying since 2013 and has logged thousands of hours of flight. It has a wingspan of 75 feet but the wings fold for storage. It weighs a little over 1,000 pounds.
I’ll mention one more, the Electric MC-15 Cri-Cri Cristaline Airplane. It is an unusual plane even for an electric-powered one.
It is a twin, single place and claimed the speed record for an electric powered plane at 163 miles per hour on Sept. 5, 2010. This one has no solar cells for augmentation.
It bested its old record at the Paris Air Show on June 25, 2011, with a speed of 175.5 miles per hour.
The flight time of the Cri-Cri is only 25 minutes, which is really not very practical.
I think that with all the money being spent on electric planes the result surely be a practical solar assisted general aviation plane in the next few years.

Don Lee, a pilot flying out of Lawrence County Airport since 1970, has been in charge of equipment and grounds maintenance for the last several years. He can be reached at eelnod22@gmail.com.