EMG-5 Electric Motorglider

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

This isn’t Brian Carpenter’s first time at the small airplane rodeo.  He’s built at least a dozen aircraft, designed several from scratch, and even entertained the hosts of TV’s Mythbusters series with a series of rides in his team’s ultralights. His latest creation at Tangent Aircraft is a sleek Part 103 ultralight that seems to break or bend the rules on several fronts, presenting a twin-pivoting-motored, Fowler-flapped, retractable-gear craft that would seem to be too complex to fall into legal 103 status – or even into something the average novice private pilot would be allowed to fly.  The 36-foot span and 105-square-foot wing would seem too fast to meet stall limits. Carpenter explained his design philosophy to your editor a few days ago, and he said the greatest challenge of meeting part 103 regulations was attaining the stall speed requirement with the small wing area.  Normal, unflapped ultralights need about 140 square feet to meet the 27.6 mph stall speed.  …

Electric Lazair Progress

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

During a visit to the International Vintage Sailplane Meet at Harris Hill, New York, your editor was fortunate to be a guest of Dale and Carmen Kramer, who graciously showed their home, once that of Glenn Curtis, “The Father of Naval Aviation.” Now the Hammondsport cottage (as in Glenn Hammond Curtis), which overlooks the lake where Curtis flew his early amphibians, is home to a high-tech cottage industry, with Dale creating battery monitoring systems, “brain boxes”, and other elements of his electrical power system for ultralight aircraft.  He designs the schematic and printed circuit boards for the system, sends them off to a PCB manufacturer and hand mounts very small components on the finished circuit boards, a process that would normally use expensive “pick and place” machinery and wave soldering.  His low-tech version of wave soldering takes place in a toaster oven. A table on the covered and shaded front porch overlooks the lake and holds stacks of water-jet cut …

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.” …

World’s First Electric Amphibian

Dean Sigler Electric Powerplants, Sustainable Aviation 7 Comments

Just days after flying his electric Lazair for the first time, Dale Kramer attached a float, outriggers, and retractable landing gear to his ultralight craft, took off from the grass field near his home, and flew to a nearby lake to make his first water landings and takeoffs.  He even managed to ridge soar the aircraft and stalk floating ducks. Having designed the Lazair 30 years ago, Kramer was heavily involved in the burgeoning ultralight movement, and over 1,200 of the twin-engined craft were built.  Today, he’s taking a lead in creating a low-cost ultralight electric flyer, topping the considerable accomplishment with a true world first – a twin-motored ultralight electric amphibian. He uses a pair of Joby JM1 motors, monitored by Eagle Tree instuments mounted to a piece of wood that was part of Kramer’s house in Hammondsport, New York.  The house, Kramer found after living there nine years, was once home to Glenn Curtiss, chief rival to the Wright Brothers …

Electric Gull Flies at Arlington

Dean Sigler Electric Powerplants, Sustainable Aviation 3 Comments

The annual fly in at Arlington, Washington was an electric landing zone for Mark Beierle’s Gull 2000, powered by his own design 20-kilowatt motor.  The 36-coil, 42 magnet disk, weighing 16 pounds, is mounted on a truss arrangement behind the airplane’s high wing, and drives a ground-adjustable pusher propeller. Flying five half-hour demonstration flights during the half-week event accounted for almost half the six hours total time on the airplane so far. The airplane has a 74-Volt Rhino Lithium-polymer battery pack made up to 11 packs in a parallel/series arrangement. Beierle says this array, and taking voltage from the ends of each 3.7-Volt series pack, allows balancing of all 210 cells. Power is run through a 500-Amp Kelly controller, which weighs about 12 pounds: Beierle hopes to try a new Kelly unit which will be half that weight and less expensive.   Battery protection is provided by circuits in the charger, which will be the same Kelly unit Beierle uses in recharging his …

Another Electric Lazair

Dean Sigler Electric Powerplants, Sustainable Aviation 1 Comment

Besides the incentives offered by the Green Flight Challenge and the Lindbergh Electric Aircraft Prize, a venerable institution is encouraging electric flight with a series of prizes.  The Experimental Aircraft  Associations plans on awarding $60,000 to electric flight competitors during this year’s AirVenture in Oshkosh, Wisconsin. According to EAA’s Newsline, “One entry in the EAA’s $60,000 Electric Flight Prize during AirVenture comes from a well-established design, the Electric Lazair, based on an ultralight designed more than 30 years ago by Dale Kramer, EAA 145132. Between 1979 and 1985, his company, Ultraflight, produced about 1,200 kits. Calling the twin-engine Lazair ‘an ideal vehicle for electric conversion,’ Kramer wrote that he has dabbled in trying to ‘electrify’ one several times.” Kramer recounted making several “thwarted” attempts, but shared the news of a Lazair flying in England on two Plettenberg Predator motors, as reported in this blog. Kramer said the radio-control world “has been invaluable to me in obtaining knowledge that I need to …