Electric Propulsion for Big Birds

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Graham Warwick reports in the August 25 Aviation Week that NASA is investigating the creation of megawatt-scale electric propulsion systems for airliners.  These would be much more powerful than those in cars or even semi-trucks, and far lighter than equivalent units in ships. NASA’s research involves partnering with the University of Illinois, Ohio State University, General Electric, and Boeing.  NASA Glenn Research Center is working on its own self-cooled, superconducting wound field synchronous motor as part of the overall effort. NASA’s focus, according to the article, “is on electric machines that can be used as generators (sources) and motors (loads) and power electronics that convert AC to DC (rectifiers) and DC to AC (inverters).”  Research includes wiring systems that can distribute high levels of electrical power.  These efforts would support “near- or medium-term development of partially turboelectric and hybrid-electric propulsion systems for aircraft up to single-aisle airliner size.” Ambitious Goals, Different Approaches Goals are ambitious, with NASA Research Agreements (NRAs) awarded …

Quiet May Be the New Black

Dean Sigler Diesel Powerplants, Electric Powerplants, Sustainable Aviation 1 Comment

Noisy airplanes are the bane of modern living.  (Well, that and the myriad other intrusive sounds with which we are surrounded.)  People can create and easily get signatures on petitions to close 70-year-old airports surrounded by 20-year-old housing developments, so General Aviation’s survival will at least partly depend on hushing our aircraft. We’ve been privileged to see and hear the passage of e-Genius, Pipistrel’s G4, and Chip Yates’ Long-EAS with a Craig Catto propeller, which emitted a barely discernible howl when it pushed the airplane at full power to a new time-to-climb Guinness record at the California State Airshow in early October 2013, reaching 500 meters (1,640 feet) in one minute, four seconds. This quest for quiet presses on the big airplane producers, too, anxious to be good neighbors and give passengers a less raucous flight.  One engine make, Snecma, has been working on the problem since before 2009, when this report appeared in the blog Envirofuel. “Volvo Aero will …

The Happiest Materials Scientist

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

According to his NASA biography, “Dr. Ajay Misra, a member of the Senior Executive Service, is Chief of the Structures and Materials Division in the Research & Technology Directorate at the NASA Glenn Research Center in Cleveland, Ohio.  In this position, Dr. Misra has the responsibility for planning, advocating, coordinating, organizing, directing and supervising all phases of Division research and business activities.”  At the fourth annual Electric Aircraft Symposium in Rohnert Park, California in April 2010, Dr. Misra was among the most charming and happiest of presenters – probably because he had so many happy things to talk about.  Much of the joy comes from the continuing revelations about the characteristics of carbon and boron nanotubes.  They turn out to be absolutely wonderful for thermal, structural, battery, capacitor and motor applications.  Dr. Misra’s talk sounded at times like a pitch for a wonder cure-all, but one backed with solid scientific precepts. Boron nitrate nanotubes have better high-temperature characteristics than carbon …