Echoing, in this editor’s mind, the collaboration between Oxford University and YASA motors, a recently announced motor from Belgium’s Ghent University and Magnax, makers of what they term an “axial flux machine.” Similar to YASA’s products, the motors are yokeless, which the makers claim promotes lower weight and the shortest possible flux path.
Beyond this feature, the motor/generators offer “A patented system for cooling the windings, for the lowest possible stator temperatures.” According to Magnax, their Dual permanent magnet rotors give “the highest possible torque-to-weight ratio.” Rectangular section copper wire fills more area than round wire and concentrated windings allow “the lowest possible copper losses (no coil overhangs).” Grain-oriented electric steel lowers “core losses by as much as 85-percent.”
The company’s white paper gives graphic and written explanations as to why these factors enable the Magnax motors to achieve 96-percent efficiency. While the company compares their motors to large, stationary industrial motors which apply radial flux to their operation, it might be more productive to compare them to other lightweight axial flux units, such as those from Emrax or YASA.
Exploded view of Magnax motor shows key features
Magnax shows, in its white paper, that their motors can be as small as 150 millimeters (5.9 inches) in diameter to over 5,400 mm (212.6 inches). The larger sizes would be destined for industrial or wind turbine applications.
Emrax motors range from 188 mm to 348 mm, all designed for power applications on lightweight devices. The 188 mm unit produces 70 kilowatts (93.8 pounds) from 6.8 kg. (14.96 pounds), while the 348 mm motor can put out 300 kW (402 hp.) from its 40 kilogram (88 pound) mass. Peak torques for the larger motor is a massive 1,000 Newton-meters (737 foot-pounds). The 188 produces 6.27 hp. per pound: the 348 makes about 4.6 hp. per pound.
Magnax motor as it might be mounted in a light aircraft
Magnax’s white paper makes a direct comparison between YASA’s P400S and their AXF275. The 305 mm. diameter P400S weighs 27 kilograms (59.4 pounds), while the AXF275 (mm. diameter) weighs 24 kg. (52.8 pounds). The P400S puts out 160 kilowatts for a maximum power density of 5.92 kilowatts per kilogram. Magnax takes it up a notch, though, with its claimed 300 kilowatt maximum power for a power density of 12.5 kilowatts per kilogram.
The company hopes to have production motors available by the end of this year, with some introductions in October. With direct drive and significant power-to-weight ratios, Magnax’s intended markets in transportation and wind turbines seem like logical places to see this technology in action. Now, if we could see a similar improvement in batteries….
Lange Aviation explained the large glider-like machine on display at the 2018 Aero Expo this way: “During this year’s AERO in Friedrichshafen, a mock-up of the Antares E2 was displayed publicly for the first time by our sister company, Lange Research Aircraft GmbH. The Antares E2 is an aircraft with an extreme endurance and very high reliability, which has been designed primarily to address maritime monitoring tasks such as fishery control. In order to fulfill the design goals, a novel propulsive system using six fuel-cell systems and six over-wing propulsors has been developed.
Lange E2 garnered considerable media attention
A Large, Heavy Machine Beyond Glider Status
Weighing in at a hefty 1,650 kilograms (3,630 pounds), the Lange E2 carries that weight on a 23 meter (75.45 feet) wingspan. Part of that is the 300 kilograms (660 pounds) of methanol that powers the six 6.7 kilowatt (8.98 horsepower) fuel cells that in turn power the six 15 kilowatt (20.1 hp.) motors.
High wing loading brings high speed, the E2 capable of a top rate of 135 knots (155.25 mph) and a stall speed of 62 knots (68.2 mph). Clean design and the efficiency of fuel cells enables an endurance of up to 40 hours, a range of 5.400 kilometers (3,348 miles). It can carry a 200 kilogram (440 pound) payload to 20,000 feet and power its sensors and communications links with a four-kilowatt, 28 Volt DC power supply.
As noted on Lange’s web site, “’The E2 is only a glider at first glance,’ says CEO Axel Lange, in fact, it is a flying sensor platform for research purposes, which can remain in the air with fuel cell drive about 40 hours in the air….’” Initial tests will be performed with a manned version, but later, the E2 will fly autonomously on missions such as border patrols or identification of marine pollution.
Lange E2 pilot will have a formidable array to monitor. Later flights will be autonomous
Lange emphasizes redundancy onboard the E2. Besides a quadruple redundant main computer, systems include:
6 x fuel cells with reformer and DC / DC
6 x propulsors with integrated inverters
2 x propulsive power bus, reconfigurable
3 x system power bus, SOH voting
9 x data-bus in three branches (CAN)
Lange Antares E2 feature multiple redundant systems
Methanol Fuel Cell Economy
The Antares E2’s energy supply uses fuel cells with an integrated methanol reformer system claimed to be “superior to other forms of energy supply, especially when there is a long-term and constant need for energy. This is because the reformer allows the extraction of much higher energy than standard burner motors.”
Methanol fuel cells enable 40-hour missions
For additional energy during maneuvers such as takeoffs, the system uses lithium-ion battery modules mounted in the wing inner nose. According to Lange, “Each cell is voltage and temperature-monitored with multiple redundancies. In addition, the modules have battery-heating systems in order to allow use at optimal temperature ranges.”
The fuel cell system, with an inverter from Elmo Motion Control, was tested at Lange. Five other systems built by Serenergy passed the Factory Acceptance Test. All the DC-DC converters were therefore built and successfully tested.
Efficiency and Economy for Future Missions
Lange Research notes, “Observation and surveillance missions are mostly implemented by using conventional, ie petrol-driven, aircrafts. The Antares E2 wants to make the implementation of missions much more efficient due to its lesser fuel consumption and lower costs of preparation. This new economic efficiency also wants to open the market for new missions, which are not yet ready for their high cost.”
Following certification for Pipistrel’s Alpha Electro trainer in Australia, China, and Canada, the FAA presented this highly-valued acknowledgment that the aircraft meets current airworthiness standards. After waiting for the agency to remove the restrictive word “reciprocating” from its Light Sport Aircraft regulations, electric aircraft designers have permission to field aircraft with truly modern powerplants.
With FAA inspectors painstakingly perusing every part of the Electros, a formal presentation followed, enabling the Sustainable Aviation Project to move forward with plans to bring low-cost pilot training to the Fresno, California area.
FAA officials display certification document for Alpha Electro trainer, a first in America
Officials from the four cities in which Alpha Electros will be hangared were on hand to lend encouragement during the public flight displays of the aircraft.
For a thoroughly modern design, the Alpha Electro is very light, at 368 kilograms (809 pounds) with batteries. Compare that to a Piper J3 Cub, which with a 65-horsepower Continental engine weighed 765 pounds empty. Adding 12 gallons of gasoline to fill its tank, though, would have given a weight of 837 pounds. Even that Cub would have used a minimum of four gallons an hour – $20 worth of non-renewable resources.
The trainers are priced around $130,000 and with projected $3 per hour direct operating costs should fulfill their mission to bring flight training to a broader audience.
You can see videos of the Alpha Electros flying and various local dignitaries commenting on the event here and here.
Meanwhile, at Cypress College, Virtually
Sabi Apai, Pipistrel’s California dealer, delivered the second X-ALPHA Virtual Reality trainer to Cypress College, a community college located about 25 miles southeast of downtown Los Angeles. The first simulator has been operating at Compton Airport for several months, and more such units are anticipated in the Los Angeles and Central Valley regions.
Sabi Apai (standing) delivers virtual reality trainer to Cypress College
As reported by Apai, the simulator had to be lifted up “several flights of stairs (with the help of several students) because we missed out on using the service elevator by about half an inch.
“After unpacking and installing the systems that have been removed for transit we nervously turned on the power switch and to my surprise (because it meant we had everything plugged in correctly) everything fired up and within minutes we had staff and students in the simulator with a grin from ear-to-ear.”
The virtual reality part is a huge sales point for this system. According to Pipistrel, “The single most important element of our simulator system is virtual reality.
“The X-ALPHA uses VR (Virtual Reality) headset instead of the usual monitors.
“This is a huge advantage because the headset allows the pilot a 360-degree view of the cockpit and the landscape. You can lean closer to the instrument panel to read the marks written in smaller font, look through the window and check if the landing gear is still in one piece after the landing or whether the flaps are indeed in the second position and did I mention sound? Sound comes through the VR headset that replicates the throttle setting and noise of the actual aircraft.”
With highly developed and refined flight vehicles and simulators, coupled with quiet electric power and economy of operation, Pipistrel could be leading the way in introducing new and returning student pilots to a green aviation future.
Mary Grady, writing in AVweb, reports that “Siemens brought its prototype electric aircraft to the U.S. this week for the first time, showcasing the airplane at the company’s Innovation Day in Chicago. ‘Electric propulsion is one of the transformative technologies that will help the industry meet the goals of reduced fuel, emissions and noise,’ said Teri Hamlin, vice president of electric propulsion for Siemens. ‘By accomplishing testing on our systems on select flying testbeds in the lower power classes, we are gaining valuable experience and knowledge that accelerates and validates our other developments in hybrid-electric propulsion systems in the high power classes.’“
Testing in Waco
Further testing of the technology will take place in Waco, Texas, at the Texas State Technical College Airfield. The eFusion with its Siemens 55-kilowatt electric propulsion unit, “Will be key in data collection on new electric propulsion systems, enabling safety standards and certification efforts for the aerospace market.” Lessons learned from the eFusion will benefit Airbus on their “City Airbus” demonstrator, a VTOL (vertical takeoff and landing) craft designed for urban mobility in conjunction with Roll-Royce and Siemens.
A Double-Play at Friedrichshafen
Following last season’s twin battery-powered Magnus eFusion formation flight at the Smart Flyer Challenge in Switzerland, Siemens and Magnus showed up at Aero Expo in Friedrichshafen with a battery electric eFusion and a hybrid eFusion powered by a Siemens motor and an EcoFly Diesel unit based on a Mercedes Smart Car engine.
Siemens Magnus eFusions in formation, trailed by a Rotax-powered version
The battery-powered eFusion is very much what was shown at the Smart Flyer Challenge, with the addition of a new, compact inverter (see below).
The hybrid version manages to fill an engine compartment with a Siemens SP55D motor, an Ecofly 800-cubic-centimeter Diesel engine, batteries and electronic control gear. The airplane doubtless loses some batteries, allowing the weight of the 89 kilogram (195.8 pound) engine to be accommodated.
Its frugal sipping of Diesel fuel or Jet-A at seven liters (1.85 U. S. gallons) per hour will enable this Light Sport Aircraft to range far afield For comparison, the Magnus 212 on which the hybrid is based consumes 16 to 21 liters per hour, typical of Rotax-powered Light Sport Aircraft. Because of this economy, Ecofly claims an astonishing range of 4,000 kilometers (2,480 miles) for the engine powering their FK9 testbed.
Hybridization might be an intermediate answer for light aircraft while we wait for the ever-promised 10X batteries of the future.
Although the Smart Car engine is not as aesthetically pleasing as many opposed cylinder flat-fours, its economical ways may win over many .
An Ultralight Inverter/Motor Controller
Siemens claims their tiny inverter has the highest power density for electric and hybrid-electric aircraft. Flying in their Magnus eFusion electric test plane, the Siemens inverter “SD104” uses silicon-carbide semiconductors and has a micro channel cooling plate. The power electronics fit in a box of 47millimeters by 94mm by141mm (1.85 inches by 3.7 inches by 5.55 inches) and weighs only 900grams (1.98 pounds). It delivers a maximum of 104kVA of propulsive power.
Siemens Magnus eFusion hybrid, with compact inverter atop unit to right
With ongoing efforts to develop power electronics and lighter, more powerful motors, Siemens seems to be positioning itself to provide electric propulsion to a wide range of aircraft – from ultralights to urban sky taxis to future airliners.
Its translucent wing shimmering on the wall above Hall A7 at Friedrichshafen’s 2018 Aero Expo, A-I-R’s ATOS Wing commanded the attention of show goers. A-I-R (Aeronautic Innovation Rühle & Co GmbH) produces a line of ultralight hang gliders and electrically-powered craft based on a common wing design modified for different weight and performance requirements. Note the large wing at about 35 seconds into this perambulation around Hall A7, along with tantalizing glimpses of the other displays that we will cover in the near future.
Although ethereal in appearance, ATOS wings can carry significant loads compared to their minimal weight. The 50 kilogram (110 pound) VRS 280, for instance, can carry an all-up weight of 330 kilograms (726 pounds), an impressive structural weight to gross weight ratio. Coupled with the Wing’s 28:1 claimed glide ratio and 0.55 meters per second (108.3 feet per minute) rate of sink, the Wing will allow long, lazy glides from altitude and even permit modest cross-country flights.
A-I-R ATOS Wing coupled with somewhat conventional fuselage and FES-like folding propeller ostensibly allows 28:1 glide ratio
The electrified Wing fits in the 120 kilogram (264 pounds) empty weight category and can carry up to a 110-kilogram (242 pound) pilot. The 506 pound total carried on a 14.5 meter (47.6 feet) span equals a very light span loading of 10.6 pounds per foot. A high-performance 15-meter class sailplane such as a Windward Performance Duckhawk carries 19.5 pounds per foot of span.
Variations using different forms of the basic wing and the ubiquitous Eck/Geiger electric motors showed up at last year’s Greilinger Elektroflugtage (Greilinger Electric Flying Days). This was the second outing for the event and “A forum for the exchange of pilots among themselves and between the manufacturers of aircraft and components instead. Devices were shown from the model airplane to the aircraft of the 120 KG class.”
As a report on the get-together explains, must of the hang gliders and “trike” setups had ATOS wings and Eck/Geiger motors. A-I-R allows the use of its wing’s many variants on myriad platforms, and continues to develop new ways of exploiting their strength and aerodynamic finesse. This efficiency enables surprising performance on limited power, and excellent gliding performance allows the use of smaller battery packs.
These ultralight developments could bring back, in a new and improved way, the old part 103, only transfigured into quiet, green machines with low operating costs and much better reliability than the noisy two-stroke engines that once powered these craft. It’s a future for low-cost flight that is worth exploring.
Two varying approaches to battery development may hold clues to future directions for energy storage. At the same time, their announcements, promising as they seem, reinforce our cautious attitudes toward how battery performance numbers are presented.
PNNL Attacks the Electrolyte Issue
According to Green Optimistic,“Researchers from the Pacific Northwest National Laboratory (PNNL) have developed a new formula for battery’s electrolyte solution to enhance its performance unprecedentedly in terms of its service life and storage capacity or an electric vehicle’s range.”
The video gives an overview of what it takes to make a battery and hints at the reasons battery research takes so long to give up improved energy storage devices.
Unprecedented the development may be, and the promise of a battery with a 7X longer lifespan and two-to-three times longer range than currently-available batteries certainly captures our attention. Its own press release suggests that PNNL researchers are enthusiastic about the longevity of their new chemistry. “When it comes to the special sauce of batteries, researchers … have discovered it’s all about the salt concentration. By getting the right amount of salt, right where they want it, they’ve demonstrated a small lithium-metal battery can re-charge about seven times more than batteries with conventional electrolytes.
Neither the press release nor the Green Optimistic report, however, provide greater detail about the greater range possible with the new chemistry. PNNL’s headline gives a clue, “Research hints at double the driving range for electric vehicles.” Beyond that, they note that “Lithium-metal batteries that replace a graphite electrode with a lithium electrode are the ‘holy grail’ of energy storage systems because lithium has a greater storage capacity and, therefore, a lithium-metal battery has double or triple the storage capacity. That extra power enables electric vehicles to drive more than two times longer between charges.” That “extra power” in sizes adaptable to EVs may be yet on the horizon, tests having been performed so far on coin-sized test cells.
The “catch” up to now is that the electrolytes used in today’s batteries corrode the electrodes, resulting in shorter overall lives for the cells.
PNNL thinks the key to the battery kingdom lies in electrolytes
PNNL has apparently solved this set of opposing forces with a new “secret sauce” that contains the right amount of lithium salts. “Their study published in the journal Advanced Materials found out that increasing the concentration of lithium-based salt in the electrolyte solution forms a barrier around the electrodes, protecting them from corrosion and ultimately, lengthening the battery life.” Two more problems arise from this solution, though.
First, the lithium-based salt is expensive. Second, increased salt concentration increases the electrolyte viscosity and lowers its conductivity. Researchers found a fluorine-based solvent solved the quandary.
PNNL senior battery researcher Ji Guang “Jason” Zhang said, “We were trying to preserve the advantage of the high concentration of salt, but offset the disadvantages. By combining a fluorine-based solvent to dilute the high concentration electrolyte, our team was able to significantly lower the total lithium salt concentration yet keep its benefits.”
While PNNL researchers investigate myriad chemistries, Sion Power of Tuscon, Arizona, has gained fame for its Lithium-sulfur cells. It claims its Licerion rechargeable lithium battery is 60-percent lighter than conventional Li-ion batteries, making it desirable for aircraft and drone use. Licerion technology, though, can be applied to many different battery chemistries, despite the company’s predilections.
Promised performance from Licerion technology would make Sion batteries aeronautically desireable
Promoted as having 500 Watt-hours per kilogram, 1,000 Watt-hours per liter, and capable of enduring 450 charge/discharge cycles, this should be the EV battery everyone has been looking for. Licerion cells are 10 centimeters X 10 centimeters X 1 centimeter (4” X 4” X 0.3”) and store 20 Amp-hours for what the company claims is “the highest energy density combination currently available.” That set of dimensions and the claimed energy storage may not confirm the 1,000 W-hrs. per liter, though.
A January 18 press release announcing a production ramp-up of the new cells explains, “At the core of Licerion technology is a protected metallic lithium thin film anode with multiple levels of physical and chemical protection to enhance the safety and life of lithium metal anodes. These anodes are paired with traditional lithium-ion intercalation cathodes.”
Sion’s partnership with BASF gives the firm access to new chemistries and their collaboration with Airbus allows testing of these developments in airborne applications. We can only hope that the numbers quoted are real-world and made available for commercial opportunities soon.
Pushevs.com remains skeptical, though. “If it is to work out as dreamed and pitched, though, the Sion Power Licerion battery could be one of the first to bring commercial electric flight to the mass market. Maybe. Perhaps. We’ll see.”
Relatively unknown to American pilots, Germany’s largest ultralight aircraft manufacturer, Comco Ikarus in Mengen, was able to announce the first flight of its successful two- seater C42 / CS as an electric version just before the start of AERO, the annual aircraft exposition in Friedrichshafen.
Geiger-powered version of Comco Ikarus C42 CS as shown at Aero Expo in Friedrichshafen, Germany
Comco’s C42 CS forms the basis for the electric version. The avgas-powered version flies with either an 80-horsepower or 100-horsepower Rotax engine, the electric version with a 32-kilowatt (50 horsepower) electric motor from Geiger Engineering. Geiger’s power package includes their dedicated controller, control lever, and monitoring instrument. Four battery packs, 15 kilograms (33 pounds) each, power the prototype, but production versions will have six packs, enabling flight times of up to 90 minutes.
Geiger makes a full array of motor, controller, and battery packages available
The first electric flight was completed by Comco Ikarus’ managing director Horst Lieb on April 15, 2018. Comco notes, “The complete electrical unit with batteries is only marginally more expensive than the combustion version.”
The aircraft, with a span of 8.71 meters (28.6 feet) and an empty weight of 280.5 kilograms (617.1 pounds), is small and lighter than most Light Sport Aircraft (LSAs), and can carry a 192 kilogram (422.4 pound) payload in its Rotax powered version. The manufacturer explains the airframe had to be modified for electrification but does not list specifications for the battery-powered prototype. Battery weight with four packs will be 132 pounds, 30 pounds more than the 17-gallons (102 pounds) of fuel carried in the Rotax machines. Performance on the 50 electrical horsepower will doubtless be less sprightly than for even the 80-horsepower gas edition.
For those concerned that the machine’s light weight might indicate a certain fragility, consider this video your editor chanced upon, showing a C42 pilot chasing a wing-suit flyer down a perilous mountain slope. Kids, don’t try this at home! (Or is this a wee bit of digital trickery?)
Canadian and American sales are handled by the Canadian distributor in Ontario, and it will probably be a while before the electric ultralight/LSA becomes available. If electric prices stay close to those for the LSA models (below $65,000 US) the airplane might be a popular favorite. After all, over 1,400 have been sold in Europe, making it one of the most popular light aircraft on the continent.
Following assorted powerplant and taxi texts, the prototype Sun Flyer 2 prototype took to the air over Centennial Airport (KAPA) south of Denver, Colorado. Further tests will expand speed, altitude, and endurance capabilities, according to Bye Aerospace.
George Bye, Founder and CEO of Bye Aerospace, enthused, “We are excited about the future and the potential the Sun Flyer family of aircraft has to revolutionize general aviation, providing improved affordability and accessibility. Lower operating costs are key to solving the student pilot drop-out rate, which is curtailing the successful attainment of badly needed airline pilots. The Sun Flyer 2’s $3 hourly operating costs are 10 times lower than traditional piston-engine flight trainers, with no carbon emissions and significantly reduced noise.”
Such economies have probably contributed to the 121 reservations for Sun Flyers by organizations such as Spartan College of Aeronautics and Technology, where students might be able to avoid taking out loans to obtain their licenses and ratings. According to Aviation Week, George claims, “Flight schools desperately need this aircraft,” a step into the future from current hard-working trainers. Those who’ve grumbled about the lack of shoulder room in current side-by-side machines will find relief in Sun Flyer’s 46-inch wide cabin, which can accommodate two 220-pounders. Occupants will face an Avidyne glass panel, and can avoid fateful smacks on the ground with the full-airplane ballistic recovery parachute.
featuring a best climb rate of 1,150 fpm; normal speed range of 55-120 kt.; maximum endurance of 3.5 flight hours; super-recharge time of 30 minutes; zero emissions and nearly silent operation, as reported by Aviation Week, Sun Flyer will have a lot to offer students and operators.
With only one moving part in the motor, maintenance will be “minimal,” and Bye estimates operating costs at about $14 per hour.
Batteries are not as efficient at producing the energy per pound that gasoline or Diesel fuels manage, but the LG Chem “MJ1” lithium-ion cells installed in the Sun Flyer are capable of 260 Watt-hours per kilogram. EPS, Electric Power Systems, is contracted with Bye Aerospace to provide a complete energy package on Sun Flyers – both the two-seat 2 and four-seat 4, which will be brought to market soon. EPS will supply battery modules (packs), battery management units and power distribution units.
Nathan Milleam, Chief Executive Officer for EPS, says, “This partnership aligns with our shared vision to advance all-electric aircraft for commercial aviation applications. Our Energy Storage System leverages technology developed for NASA’s X57 platform, that enables our Battery Module to meet stringent FAA safety requirements around containment of cells in thermal runaway at a very light weight.”
Charlie Johnson, Bye Aerospace President, “extremely pleased to launch the test flight phase for the Sun Flyer 2 program,” hailed the “fantastic first flight.” Bye Aerospace notes the Sun Flyer family of aircraft, including the Sun Flyer 2 and the 4-seat Sun Flyer 4 will be the first FAA-certified, U.S.-sponsored, practical, all-electric airplanes to serve the flight training and general aviation markets.
100 years ago, a great air race – “The Great Air Race” – in fact, was held with competitors flying from Great Britain to the Northern Territories of Australia. Crews had 30 days to make the trip, and considering the reliability of engines at that time and the primitive nature of aerial navigation, very little time to relax.
Of the six teams that entered, only two made it, three crashing (two fatally) and a fourth team being imprisoned in Yugoslavia as suspected Bolsheviks. Only two teams finished, and only one received the 10,000 Pound Sterling prize (about 544,577 pounds today – over $775,000), enough to cause the six crews to accept the high risk involved.
Captain Ross Smith with 10,000-pound prize money – equal to over a half-million today
The winning flight, in a Vickers Vimy WWI bomber, inspired the founders of Qantas to begin regular airline service in the country, with that company, nearly a century later, able to offer transit from Los Angeles to Sydney for under $1,500 (under $100 in 1919 currency). They have just added non-stop flights from Europe to Australia with Qantas’ great reliability and safety – a far cry from the derring-do of 1919.
“On the morning of November 12 1919, pilots Ross and Keith Smith, along with mechanics Sergeants Wally Shiers and Jim Bennett, took off in their Vickers Vimy G-EAOU from Hounslow aerodrome in West London.
“Over the next 29 days they passed through countries including France, Italy, Greece, Egypt, Iran, Pakistan, India, Myanmar, Singapore and Indonesia before touching down at Fannie Bay, Northern Territory.
“The realization that it was possible to fly from Australia to Great Britain was part of the inspiration that spurred the founding of Qantas, by Paul McGinness and Hudson Fysh, in 1920.”
Richard Glassock, a fellow at Nottingham University, emailed to report on plans to recreate the 1919 race and even a better-equipped 1934 air race from England to Australia, the MacRobertson Trophy Air Race.
Richard thinks the use of fuel-cell-energized, electric, all composite craft noted in contest rules will be the kind of technological leap that took place in the 15 years between the Great Air Race and the MacRobertson.
His interest in the projected event is echoed by University of NSW Emeritus Professor of physics John Storey, who said the race would help spur innovation in battery technology.
“The heart of the problem is to store enough energy in the batteries without making the aircraft weigh like an elephant,” Professor Storey said.
“The event is technically feasible, but being able to complete the route within 30 days is by no means a foregone conclusion.
“That makes 2019 the right time to stage it: in 2009 it would have been impossible, in 2029 it will be routine. It’s a very happy coincidence.”
According to Flight Safety Australia, “The 2019 race is sponsored by the Northern Territory government, which has adopted a suggestion made by entrepreneur Dick Smith that the centenary of the original race be marked by a similar race for electric aircraft.
The 2019 race will be for three categories of aircraft:
Battery electric, which must use batteries, wind turbines or solar power to turn an electric motor.
Hydrogen fuel-cell electric, which must use the above methods and hydrogen.
Hybrid combustion-engine electric, which must be series hybrid, without any direct drive between the fossil fuel engine and the propeller or propulsion turbine.
Aircraft can be fixed wing, rotorcraft or lighter than air.
Middle East Short Course Racing
Some will wonder about the range required for even the shortest legs of the Great Air Race. Organizers in Dubai are betting their Air Race E contestants will be able to stay in the air long enough for their eight laps around a five-kilometer (3.1 mile) course marked out by pylons, emulating Formula 1 air races seen at Reno, Nevada.
Air Race E course emulates that of Formula 1 racing
Even with throttles to the firewall, competitors should manage the 24.8 mile course, the G-forces of the turns putting a greater strain on pilots than on the motors or batteries. Conversions of exiting Formula 1 racers or new designs meant to optimize things for electric power should provide plenty of thrills for spectators as the aircraft buzz by, eight at a time.
Less eclectic than the Great Air Race, Air Race E contenders will be limited to electric, battery-powered, propeller-driven craft of a certain weight and size.
Across the Pacific, Electrically
Another event will capitalize on unpiloted craft to make the 4,500 mile jump from Japan to California non-stop. One competitor has accepted the challenge presented by iRobotics of Tokyo. Their audacious idea, to fly from Tokyo to San Francisco, seems like something that would challenge most large commercial aircraft using the best generally-accepted technology of our day. To add that the airplane will be unpiloted and powered by electricity adds a level of difficulty that makes this seem almost ludicrous.
“A Japanese drone start-up is throwing out a challenge to all comers for a drone race from Tokyo to San Francisco. It sounds far-fetched, but a lot indicates that the race could happen much sooner than you think. Even if drones taking part will need AI, flight-control software, sensors and batteries that hardly exist today.”
Sabrewings Draco-2, a competitor for the trans-Pacific Drone Race
So far, they have one challenger, Sabrewings Aircraft, headed by Ed De Reyes. A test pilot, a flight test engineer, and an FAA liaison for small and large companies alike, on various programs and projects. Ed is the Chief Executive Officer and co-founder of Sabrewing.
Both the iRobotics machine and the Sabrewing Draco-2 UAS are reputed to be capable of the 4,500 mile trip, and will feature dazzling arrays of technology and clever design. For the Draco-2, Sabrewing lists the following:
“The DRACO-2 is designed to fly non-stop and un-refueled for 4,500 nautical miles (8,800 kilometers). It launches from a standard runway, and provides near-real-time video from on-board the air vehicle for the first 150 miles of flight. At cruise altitude, it then switches to high-resolution, low-light, on-board cameras that are updated every 5 seconds and provide a view of the aircraft path and the air vehicle’s location over land or water. Day or night, good weather or bad, the Rapier has the capability of flying for days without stopping or refueling.
“For added safety, the DRACO-2 has a unique, proprietary sense-and-avoid sensor suite that detects objects that may conflict with the air vehicle’s flight path – and can instantly turn right or left, climb or descend – to autonomously avoid anything in its way…even as small as a bird. The DRACO-2 can even fly safely on two rotors – and every essential system on board is redundant to assure mission completion.
“The DRACO-2 is controlled via satellite, and is in constant communication with both the Launch and Recover Element (“LRE” – located at the launch point in Japan) and Mission Control Element (“MCE” – located at the destination landing point of Moffett Field, Mountain View, California, USA). The air vehicle is monitored by two pilots on the ground, in constant contact with Air Traffic Control. The trip is expected to last about 45 hours – and provide spectacular views of the air vehicle and its flight path – both day and night – while in flight.
iRobotics, in tendering its challenge, is fearless in taking on all challengers. They explain, “It might initially sounds strange, but iRobotics are hoping that giants like Boeing, Airbus, Google and many others will rise to the challenge. The Japanese start-up is not afraid of taking on companies that are easily 1,000 times bigger than them.
“It’s a gamble, of course. However, we feel that the race is a unique proposition that can help develop drones. We are pushing technology, making it capable of solving some of the challenges the human race faces. At the same time, it’s no secret that we’re hoping to make a profit, which I don’t think is wrong. It’s a situation where we’re having fun working on something we’re passionate about, which we believe will have a positive impact on the world, while challenging the idea of what can and can’t be done. It’s pretty much a perfect recipe,” Yoshiyasu Ando (CEO of iRobotics) says.
With three major electric air races with different goals, we might see a new golden age of (electric) air racing in the next few years. Racing does improve the breed, as great car makers have long known.
News from Joseph Oldham, founder of the Sustainable Aviation Project, and Michael Coates, United States master distributor for Pipistrel Aircraft, heralds the largest delivery of electric training aircraft to date. Four Pipistrel Alpha Electro Trainers showed up at Fresno, California’s Chandler Airport, all part of the Sustainable Aviation Project. Described as “a public-private collaboration to reduce the cost of flight training through the use of all-electric general aviation airplanes,” the Project might become a role model for future electric flight training.
On March 19, two 18-wheel trucks delivered two 40-foot shipping containers. Each container carried two Alpha Electros, two chargers, and a pair of replacement battery packs for each airplane. It took a mere two hours for a volunteer crew of up to six to remove the aircraft and chargers from the containers, leaving an X-Alpha simulator to be sent on its lonely way to Cypress College in Los Angeles.
Three of the four Alpha Electros after being removed from their plastic sheaths and assembled
Michael Coates reported, “After removing all the plastic wrapping it took about 10 minutes per plane to install the wings and horizontal stabilizers; the way Pipistrel designed the planes makes installation of the wings an easy process especially with all of our helpers on-hand.
“…Coates… was joined by Sabi Apai, the Pipistrel dealer for California who both helped guide the unloading and assembly process and were a great help!
“The planes had been in the containers at sea for 3 months due to incorrect shipping routing by CMA-CGM (dig intended and no apology from them received) where they endlessly sailed the world’s oceans and yet, the batteries were still at from 43% to 53% State of Charge when unloaded. All aircraft were charged to the recommended resting charge of 60-65% the next day.”
A Flight Program That Allows Cross-Country Electric Flight
Joseph Oldham is a driving force behind this electrification of flight training in the Central Valley. Aircraft and chargers will be fielded at Reedley Municipal Airport (032), William Robert Johnston Municipal Airport in Mendota (M90), Fresno Chandler Executive Airport (KFCH), and Fresno Yosemite International Airport (KFAT). This distribution was planned by Joseph and Richard Duncan, manager of Fresno Chandler Executive Airport. Working with project partners including the Cities of Reedley and Mendota, Reedley College, the Fresno Business Council and the CALSTART San Joaquin Valley Clean Transportation Center, they came up with a plan that allows the admittedly short-range aircraft to leave the traffic pattern, fly to a participating airport, recharge, and return. Cross-country trips will enable student pilots to gain the full gamut of skills necessary to achieve full certification.
Oldham explains in his press release, “We ended up with a unique public-private collaboration … to prove electric airplanes can dramatically cut the cost of flight training, and venture beyond the traffic pattern. The planes are being used to provide flight training for disadvantaged youth in the San Joaquin Valley with a primary focus on youth from the City of Reedley and the City of Mendota, both rural farming communities with high unemployment levels. We have set up a new non-profit corporation, New Vision Aviation, that will provide the flight training, operate, and maintain the aircraft on behalf of the two cities and we have just completed our instructor training program after getting our instructors validated on the aircraft. Now is the time for students to take to the skies.”
The Pipistrel Alpha Electro
Michael Coates explained to your editor that the motor powering the Alpha Electro is a product of their own making, and their Information Pack for the airplane adds that it is an Emrax motor modified by Pipistrel for use in this particular airplane. The Electro 60 motor and controller puts out 60 kilowatts (80.4 horsepower) maximum power for up to one minute and 50 kW (67 hp.) continuously. Samsung batteries contained in Pipistrel-made battery boxes and controlled by Pipistrel battery management systems (BMS) allow up to an hour in a traffic pattern with a 20 minute reserve for the Light Sport Aircraft version of the plane. Cross-country trips can last up to 45 minutes with 18 kilowatts consumed at 75 knots (86 mph) from the 21 kilowatt=hour pack.
The strategic positioning of the airports chosen for this training program allows for safe transit between the fields, with each offering the full-service needs of visiting aircraft. Chargers enable “refills” of battery packs, and spare, fully-charged packs allow five-minute swaps – not any worse than climbing on a ladder, dip-sticking the tank and performing refueling on a conventional airplane.
Low Operating and Maintenance Costs
From your editor’s own experience, a Cessna 150 can consume five to seven gallons of avgas per hour at a cost of $4.96 to $5.55 a gallon, as reported by 100LL.com. Locally (Aloha, Oregon), Portland General Electric charges residential users a low of 8.8 cents to a high of 18.1 cents per kilowatt-hour of electricity. The 21-kilowatt-hour pack on the Alpha Electro would cost $1.85 to $3.80 for a full charge at those rates.
Oldham reports in his blog for the project that 100LL and electricity costs in the Fresno Valley area are among the highest in the nation, with avgas at $6.55 per gallon. Oldham reviews hours and rates for the following: “The aircraft will fly 4 hours per day and operate 6 days per week. Each aircraft will be fully charged overnight using off-peak electricity at $.18 per kWh for the first hour of flight @ $2.52. Hour 2 will be charged using partial peak electricity at $.25 per kWh @ $3.50. Hour 3 will be charged using peak electricity at $.55 per kWh @ $7.70. Hour 4 will be charged at peak electricity at $.55 per kWh @ $7.70. This results in a weekday average cost of electricity for 56 kWh per day of $5.35 per hour. Weekend flights on Saturday will be a flat $2.52 per hour using the off-peak electricity. Total weekly cost of electricity is estimated to be $117.18 for 24 hours of flight time which yields an average cost of $4.88 per hour. This estimate is for summer operations.
Sectional of four project airports shows proximity within Alpha Electro range
“During the winter, there [are] no peak demand costs, only partial and off-peak. In this case the average should be about $.19 per kWh for the 56 kWh used each day or $2.66 per hour.” These hard numbers will be hard to beat with fossil-fuel powered equivalent aircraft. Since the Alpha Trainer with the Rotax 912 UL engine burns a mere 2.5 gallons of 100LL per hour, fuel costs will be around $11.00 or $12.00. That doesn’t include the higher maintenance costs for the Rotax, though.
Titan Aircraft lists a new 912 UL at $14,337. Discussions on the web suggest that the UL engine will achieve 2,000 hours between overhauls. Many rebuilders like Brian Carpenter suggest selling the engine at that point and getting a new one from the factory. Core engines seem to fetch $2,000 to $3.500, so the replacement ends up costing about $12,000, or $6.00 per hour. Of course, maintenance, oil changes, spark plugs, etc. run that number up considerably. As noted above, direct operating costs for a traditional trainer such as a Cessna 150/152 can top $30 an hour just for fuel.
By contrast, Pipistrel’s Electro 60 motor consumes relatively little energy and has two overhaul periods at a TBO of 2,000 hours, and according to numbers from the Pipistrel Alpha Electro Information Pack an overhaul cost of 500 Euros ($616) plus 12 hours of labor. With a motor life limit of 6,000 hours, replacement will cost about 10,000 euros ($12,320).
If the Sustainable Aviation Project can achieve FAA certification and approval for their aircraft and training program, we could see an inexpensive route to attain private pilot ratings, and once-again busy private fields in rural areas. This regional approach to flight was envisioned by William T. Piper, and the Alpha Electro could be a worthy successor to the iconic Piper Cub.