Solar Impulse 2 Batteries – Better than We Thought

Dean Sigler Batteries, Solar Power, Sustainable Aviation 0 Comments

What happened to Solar Impulse 2’s batteries on those long five days and nights over the Pacific?  It took months of enforced downtime in Hawaii to have new batteries made, sent from Korea, installed, tested, and flown again.  Could the plane have completed the flight on the original batteries? Kokam, manufacturer of the airplane’s cells, has released new information that provides details of the drive system and relieves a few lingering anxieties.  An over-riding concern was that batteries overheated on the Japan to Hawaii part of the mission, topping out at 50 degrees Centigrade (122 degrees Fahrenheit) – above their design temperature.  Your editor has thought deeply about what Andre’ Borschberg must have gone through every day of the five …

An Electric Helicopter Lifts Off – Briefly

Dean Sigler Electric Powerplants, Sustainable Aviation 4 Comments

Gizmag apparently beat everybody to this story, with even Popular Science quoting from the online gadget hunter’s web site. They report that in mid-August 2011, Pascal Chretien piloted his creation, a coaxial rotor, twin Lynch-motored helicopter that he built for Solution F, a Swiss racing engine development firm.  He performed the flight “in the presence of a court appointed witness,” according to a press release from Lithium Balance, the firm that supplied the battery management system (BMS) for and acted as consultants to the project.  The “first” Chretien claims is a carefully parsed one, an “untethered, fully electric manned helicopter flight in a prototype machine.”  The fact that he designed and built a unique machine and flew it in a …