David Birkenstock and Ultimate Efficiency

Dean Sigler Sustainable Aviation Leave a Comment

According to his biography on Airliners.net, “David Birkenstock is a pilot for an east-coast charter and management firm, flying the Turbo Commander 690B and the BeechJet 400A. When he’s not flying, he’s working on modifying a light sport airplane for pressure thrust, hoping to enter it into the NASA Personal Air Vehicle Challenge. He has posted more information about pressure thrust at PressureThrust.com.” Birkenstock’s presentation at the fifth annual Electric Aircraft Symposium in Santa Rosa, California on April 29, 2011 extended his thoughts on pressure thrust, an outgrowth of Fabio Goldschmied’s theories that are well represented in the CAFE Foundation’s library. Most surprising (or maybe not surprising at all) in his talk were comments by major players in the aerospace industry. Around 2000, a senior airflow fellow for a “major airframe manufacturer was quoted as saying, “Our position is that aviation is a mature business and that the discoveries waiting to be identified are probably not worth looking for, much …

A Chance to Unwind

Dean Sigler Sustainable Aviation 4 Comments

Would you believe that there were once at least two rubber-band powered airplanes intended to carry people?  The Rubber Bandit and the RB-1 were attempts at truly flexible flight in the 1980s and ‘90s, and each elicited a brief kerfuffle in the press. Rubber Bandit was a well-designed effort to cruise the length of a runway on the thrust provided by twisted rubber bands.  Its motive power was cranked by a pickup-mounted winch that put hundreds of turns on the model-airplane-like craft’s motive source. Dave Barry was taken by the concept, and interviewed George Heaven, the plane’s designer in an August 3, 1997 column titled, “The Rubber Band Man.”  He talked about Stuff that Guys do, such as dropping bowling balls from airplanes on junked cars.  He explained that Guys, hearing about such things, responded with, “Cool!”  Women tended to say, “Why?”  Barry noted that, “Because guys like to do stuff… this explains both the Space Shuttle and mailbox vandalism.” …

Lighting Up the Electric Firefly

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

One highly enjoyable aspect of writing this blog is waking up in the morning to emails from France, announcing some exciting developments for those who love small aircraft. Fabrice Tummers from Luxembourg Special Aerotechnics (LSA) and Anne Lavrand from Electravia alerted your editor to a cooperative venture in which they swapped out the original Eck/Geiger motor/controller and Helix propeller combination  (with which the airplane set a class speed record) on LSA’s MC-30e Luciole (Firefly) for an Electravia power package. Since many of the Michel Colomban-designed MC-30s are powered by a Briggs & Stratton V-twin that produces about 26 horsepower, the new electric motor setup provides a great opportunity to compare electric and internal combustion performance. It should be a fair comparison, with the empty weight of the MC-30e with batteries registering a European legal ultralight 113 kilograms (248.6 pounds). The new system includes a 26-horsepower E-Motor GMPE 102 (motor and controller), a two-bladed E-Props wooden propeller, and a Kokam rechargeable …

It’s a Race – It’s an Economy Run

Dean Sigler Sustainable Aviation Leave a Comment

Stemme, the German manufacturer of a series of highly innovative sailplanes, motorgliders and even unmanned aerial vehicles, has announced the first Green Speed Cup, which will  take place between August 7 and 13, 2011, starting from Stausberg Airfield every day. Combining a race with an economy run, the six-day event will help illuminate the strategies different teams will use to fly “as fast as possible while minimizing the consumption of fossil fuel energy,” according to the GSC’s organizers.  Explaining that the Cup is a “a direct comparison of technologies, machines, materials and the capabilities of the pilots,” taking into account how pilots can exploit thermals and winds, Stemme expects that the competition should “practical solutions for saving energy during powered flight.” If all goes well, “Today’s standards for cruising speed, range and endurance should be reached or exceeded as far as possible.”  The contest will support a cooperative research project between Stemme and the Technical University of Dresden. Seven aircraft, …

If You Can Draw It, We Can Print It – In 3D

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Students and faculty at the University of Southampton on the southern English coast have created an unmanned aerial vehicle (UAV) in just a week, from the initial design to the finished, flying object. “Printed” from nylon on an EOS EOSINT P730 nylon laser sintering machine, the plane emerges from the device in successive layers and comes with hinges already in place, emulating the bearings, crank and headset-in-place bicycle recently produced by EADS (Airbus) using similar technology and materials. http://www.youtube.com/watch?v=aFFFiB_if18 Part of a “ground-breaking” course of study “which enables students to take a Master’s Degree in unmanned autonomous vehicle (UAV) design,” the Southampton University Layer Sintered Aircraft (SULSA) can be snap-fitted together in minutes without tools. SULSA has a 2-meter (6.4 feet) wingspan and an electric motor reputed to be “almost silent” in cruise mode (but not so much in launch mode as the video reveals).  It is steadied by a “miniature autopilot developed by Dr. Matt Bennett, one of the …

PC-Aero Wins Lindbergh Electric Aircraft Vision Award

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

A Green Flight Challenge entrant, PC-Aero’s Elektra One, has won the Lindbergh Electric Aircraft Vision Award at AirVenture 2011 in Oshkosh, Wisconsin, becoming the latest winner of this important award for innovation in the pursuit of “green” aviation. Past winners of the Lindbergh Prize for Electric Aircraft include: Pipistrel: 2011 Aero-Friedrichshafen Best  Electric Aircraft LZ Design: 2011 Aero-Friedrichshafen Best  Electric Propulsion System Solar Impulse: 2011 Aero-Friedrichshafen  Outstanding Achievement Award Yuneec International: 2010 AirVenture Best  Electric Aircraft Sonex: 2010 AirVenture Best Electric Aircraft  Subsystem Lange Aviation: 2010 AirVenture Individual  Achievement Award According to Erik Lindbergh, grandson of Charles Lindbergh and founder of LEAP, the organization’s, “Programs recognize, inspire and incentivize the innovation that drives our culture, economy and future.  The LEAP Electric Flight Program is accelerating the development of the electric aircraft industry through a range of activities, from prizes to advocacy.” This year’s award, “Focuses on innovation with a “vision” for integrated electric power for an aircraft and its supporting …

Google to Sponsor Green Flight Challenge

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

Green Flight Challenge sponsored by Google to bring historic firsts to aviation Aviation’s largest ever prize to be awarded at Moffett Field October 3 during exposition hosted by NASA SANTA ROSA, CA (July 29, 2011) – The CAFE Foundation announced today that Google will sponsor the NASA Centennial Challenge flight competition known as the Green Flight Challenge (GFC). CAFE (Comparative Aircraft Flight Efficiency) will conduct the event from September 25 through October 2, 2011 at Charles M. Schulz Sonoma County Airport.  The NASA-funded prize purse of $1.65M makes this the largest ever prize for aviation.  Competing aircraft must demonstrate at least 100 mph and 200 passenger MPG on a 200 mile flight.  The aircraft in the Green Flight Challenge sponsored by Google represent a diverse mix of singular prototypes created expressly for the competition by some of the world’s top designers. Most will be propelled by batteries and electric motors, some by bio-fuel or hybrid. All competing aircraft will be …

Elektra One Flies Into Oshkosh with Solar Cells

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation 1 Comment

As described before in this blog, PC-Aero’s Elektra One is a single-seat electric airplane with an Eck/Geiger 13.5 kilowatt motor in the nose, and now at least partially solar powered. http://www.youtube.com/watch?v=r03nim-6qBw&feature=related Designer Calin Gologan gives a walkthrough of the design features which make Elektra One such an efficient airplane, and one likely to give other competitors in the Green Flight Challenge a good run.  While he describes the thin carbon-fiber shells which comprise the airplane’s primary structure, notice the light shining through.  That thinness helps explain Elektra One’s 100 kilogram (220 pounds) empty weight, only about 100 pounds of which is structure.  The motor is 4.7 kilogram (10.34 pounds) and the controller is a 270 gram (9-1/2 ounce) model airplane marvel.  Batteries can add up to 100 kilograms and the pilot another 100 kilograms, making the strength-to-weight ratio of the craft rather impressive, and its payload carrying abilities among the greatest for flying machines. Gologan claims a maximum range of 500 …

A Very Long Towline

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

John Carpinelli has a lofty vision, borne on gossamer threads that would pull giant cargo planes into the heights. We’re familiar with the rapid ascent of a sailplane on a winch tow, pitching up into a fighter-like climb and dropping off the towline at some predetermined altitude. What if the tow ropes were attached to a large, electrically-propelled airplane, pulling a heavy jet transport to a point several kilometers above its launch? It’s not as wild-eyed as it sounds – at least according to the CleanTech Open organizers. The Cleantech Open is an organization looking to find, fund and foster startup companies in green industries, and chose Electric Takeoff, Carpinelli’s firm, as a semifinalist in the Transportation category in their recent competition. Basing his work at least partially on the “bucket drop” technique created by missionary pilot and martyr Nate Saint, Carpinelli has the advantage of a degree in electrical engineering and the historical work of others who took the …

Carplane – German for BiPod?

Dean Sigler Electric Powerplants, Sustainable Aviation 8 Comments

Carplane is an innovative enterprise in Braunschweig, Germany, intent on producing a hybrid vehicle that, while it resembles the Rutan Model 367 BiPod, differs in significant ways. The company’s “pitch” is similar to those from other roadable car developers since the Waterman Aerobile or Taylor AeroCar.  “Imagine the daily commute without transfers, exits, congestion, or missed connections,” the German Center for Research and Innovation envisions.  “As an aircraft that can also drive on roads, the Carplane® will head for its destination in a beeline without detours or stop-and-go traffic. Located in Lower Saxony, Germany, and under the general management of Angela Fleck, herself a pilot, the Carplane GmbH is in the process of building such a dual-mode vehicle. Designed as a Light Sport Aircraft (LSA), requiring only 20 hours of instruction to fly, commercial applications will include recreation, business travel, and emergency service.” Like the BiPod, Carplane has a twin cockpit catamaran-like fuselage arrangement, a “hybrid” power system, and the …