Joby “Unicorn” Gains Private, Military Backing

Dean Sigler Announcements, Batteries, Electric Powerplants, Fuel Cells, Hydrogen Fuel, Sky Taxis, Sustainable Aviation Leave a Comment

Joby Aviation is one of few “unicorns” in the electric Vertical Take Off and Landing (eVTOL) market, a billion-dollar enterprise.  With funding coming from Toyota, several venture capital investors, Uber and the U. S. Army, Joby seems poised to demonstrate Urban Air Mobility (UAM) in a serious way. In 2011 JoeBen Bevirt, founder of Joby Energy, Joby Aviation, and creator of those knobby-looking tripods you see everywhere, invited Patrick McLaughlin to visit his design studio.  Your editor got to tag along.  On Woodpecker Ridge, north of Santa Cruz, JoeBen’s barn-like studio housed about a dozen engineers and designers all working on electricity-generating kites.  He wore a T-shirt reading, “If you’re not living on the edge, you’re taking up too much room.”  That edginess has helped him, in the last decade to be a major player, with now over 500 employees in the aviation sector.  JoeBen and Patrick discussed motor design and integration with a controller Patrick had built from off-the-shelf …

Clean Jet Fuel from the Air?

Dean Sigler Announcements, Biofuels, Diesel Powerplants, Sustainable Aviation Leave a Comment

What if we could suck carbon from the air, make clean jet fuel out of it, and reduce greenhouse gas emissions by using this fuel in our airliners?  That’s a dream pursued by many researchers, and recently Rotterdam the Hague Airport announced a study to sort out the plausibility of such a plan.  First, though, we need to look at the numbers for how much fossil fuel would have to be replaced. These are Big Numbers How much fuel goes into a large jetliner?  How efficiently is it used?  These are matters of concern to airline executives on a profit-and-loss basis, and to all of us on an environmental basis.  Let’s look at the Boeing 787 Dreamliner variants for an idea of how efficient a modern airliner can be.      The 787-8 burns 4,900 kilograms (10,780 pounds) per hour or Jet A, while the larger 7879 consumes 5,600 kilograms (12,320 pounds) per hour. Converting pounds (the way the military and airlines …

Avoiding Propeller Strikes on Electric Aircraft

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation Leave a Comment

At last year’s Electric Aircraft Symposium, Ron Gremban, developer of the Prius plug-in hybrid, shared several questions about promoting safety in electric aircraft.  One aspect that provoked deep thought was that of safety for those working around an electric airplane, whose propeller could start quietly and possibly strike an unaware bystander.  During the Green Flight Challenge, it was noteworthy that unlike their gasoline-powered counterparts which idled while awaiting takeoff, the Pipistrel G4 and e-Genius awaited their turn to launch with propellers at rest, only spinning when commanded – and very quietly at that. The question of avoiding prop strikes found at least one answer at EAS VII.  Karl Kaser demonstrated, in model form, his ePropeller Safety Device (eSD), noting “the risk to people, animals or objects in the propeller disk area and that they can be injured or damaged accidentally during the run-up of the propeller.”  He first noted that issue in the case of e-Genius, on which he was …

Living Up To a Standard

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Ron Gremban is an early developer of plug-in electric hybrid (PHEV) automobiles, having helped convert hundreds of Toyota Priuses to extend their electric-only range and make them even more practical real-world automobiles. His 2008 writing on the differences between the Prius and Chevrolet’s Volt shows an ability to consider the actual physics and engineering involved rather than allowing the heat of the debate to obscure the realities. Backing from Dr. Andrew Frank of UC Davis gives further credibility to Gremban’s views. Given his demonstrated abilities and his dispassionate vision, it’s no surprise that Gremban would look at projected electric flight in ways that haven’t yet occurred to its most ardent promoters. On April 27, at the Friday evening Motors theme dinner, as part of the Electric Aircraft Symposium hosted by the CAFE Foundation, he shared some of his concerns about potential safety concerns for electrified flight. For instance, how do pilots and know that an electrically-powered propeller is “on” or activated …