Solar Impulse Down, But Not Out

Dean Sigler Batteries, Electric Powerplants, Solar Power, Sustainable Aviation Leave a Comment

Following its cliff-hangar five-day flight from Nagoya, Japan to Kalaeloa Airport, Hawaii, Solar Impulse is undergoing an extended period of tender loving care, dedicated rebuilding of its battery packs and insightful reflection on how to avoid future issues. Landing July 3, 2015, Pilot André Borschberg broke the world records for distance along a course (6,825.4 kilometers – 4,231.5 miles), Straight distance, and Duration for solar aviation, as well as the world record for the longest solo flight ever (80 hours and 5,663 km. – 3,511 miles), according to the Solar Impulse web site. If all had gone according to plan, Bertrand Piccard would have hopped on board a few days later and headed for the United States on the second leg of the trans-pacific part of the the team’s around-the-world voyage.  Unfortunately, the rigors of a test flight over Nagoya, followed by a climb to 28,000 feet too soon after that test flight, seems to have doomed at least some of the batteries. …

Researchers Strike Battery Fools Gold on Two Continents

Dean Sigler Batteries, Electric Aircraft Materials, Sustainable Aviation Leave a Comment

Better, Cheaper, Faster.  That was the mantra when your editor worked in the semiconductor manufacturing world.  Designs, processes and materials were all recalibrated constantly to enable the march toward those three goals.  And to some extent, constant repetition helped us achieve the ideal of Moore’s Law, the dictum that computer chips would double the number of transistors they contained every two years.  Transistor density in computer chips determines the level of performance they can achieve, and this doubling has yet to reach its end. Unfortunately, batteries haven’t doubled in performance every two years, but seem to follow an annual five-to-eight-percent increase in energy density.  This would mean, at best, that energy densities would double every nine years.  The Tesla Forum notes this progress would not be continuous, but introduced in steps. Without either party sharing much information on the energy densities of their experimental cells, researchers in America and Switzerland find the “super environmentally friendly” nature of fool’s gold in batteries …

Britain Puts an Electric Nose on a New Zealand Carbon Fiber Falco

Dean Sigler Batteries, Electric Aircraft Components, Electric Powerplants, Sustainable Aviation Leave a Comment

Richard Glassock, an Australian now working in Hungary, has been a presenter at an Electric Aircraft Symposium and received worldwide interest for his eight-passenger, open cockpit sailplane design a few years ago. He writes today to share news about a twin electric motor conversion for a Falco, the great, high-speed craft by Italian Stelio Frati. Originally designed for four-cylinder, horizontally-opposed engines of up to 300 horsepower, the wood airframe was incredibly complex and required thousands of hours to construct. Signor Aldini reported taking 80 hours just to make the main spar’s jig – with four people needed to complete clamping before the glue set. With the increasing difficulty of finding aircraft-grade sitka spruce or aircraft-grade wood craftsmen, those who can replace their time with money can purchase an all-carbon-fiber composite kit with qualifies under the FAA’s 51-percent rule – the homebuilder being responsible for 51 percent of the construction.  All kits for the airframe, firewall back, total over $92,000 (U. S. …

Cambridge’s “Ultimate” Battery? Wait 10 Years and See

Dean Sigler Batteries, Electric Aircraft Materials, Electric Powerplants Leave a Comment

Cambridge University researchers claim to have successfully demonstrated how several of the problems impeding the practical development of the so-called “ultimate” battery, in this case a lithium-oxygen unit, could be overcome.  They make some pretty impressive claims, saying they’ve developed a working laboratory demonstrator with “very high” energy density – comparable to that of gasoline and with greater than 90-percent efficiency, and the ability to be recharged more than 2,000 times, or 5-1/2 years with a complete cycle and recharge every day. A lithium-oxygen or lithium-air battery of this type would allow an uninterrupted drive between London and Edinburgh on a single charge, about 415 miles, over 100 miles greater than the top mileages promised by Tesla and GM at this point. Researchers add the promise of one-fifth the cost and one-fifth the weight of currently available batteries – a touchstone for electric aircraft designers, and close to the goals U. S. Energy Secretary Steven Chu asked for three years …