Zephyr Breaks Its Own Record – Again

The Royal Aeronautical Society, official record keeper for such things, announced in an August 8 press release, “Taking off from Arizona, US on 11 July, Airbus Defense’s solar-powered UAV (unpiloted aerial vehicle), the British-built Zephyr S, has smashed the existing endurance record for unrefueled, unmanned flight by staying aloft for 25 days, 23 hours and 57 minutes. This, the maiden flight of the production Zephyr S HAPS (high altitude pseudo satellite) for the UK MoD (United Kingdom Ministry of Defense), once verified, almost doubles the existing endurance flight record of 14 days, 22 minutes for UAVs, set by a previous Zephyr prototype in 2010. The solar-powered Zephyr UAV, which weighs less than 75 [kilograms – 165 pounds], flies at 70,000ft, above air traffic and weather, to provide a new class of platform for persistent surveillance, observation, communications relay or connectivity for military or commercial customers. Airbus said that the maiden flight saw test objectives met with further flights planned in the second half of 2018.”

Airbus reports, “Zephyr is a High Altitude Pseudo-Satellite (HAPS) UAS/UAV which runs on solar power. This unmanned aircraft provides local satellite-like services. It endures like a satellite, focuses like an aircraft and is cheaper than either of them.”

The previous longest flight duration record was also logged by a Zephyr prototype aircraft at over 14 days in 2010, ten times longer than any other aircraft in the world at that time.  The record flights were made with Sion Power lithium-sulfur batteries.

Craig Wilson, Managing Director of Williams Advanced Engineering said: “Airbus is a name synonymous with innovation and technology in the industry. As such, we are delighted to be working with them on this project, and hope to share some of our expertise in electrification, battery systems and advanced lightweight materials, as well as learn from their vast experience in aerospace. We are very much looking forward to working together on this project and hope the learnings from one another may continue in the future.”

Built one-at-a-time for the first three units, Zephyr’s success has prompted Airbus to create a construction facility at Farnborough in England and an operations site in Australia, where the Outback will doubtless beckon new long-distance, high-endurance records.

Jana Rosenmann, Head of Unmanned Aerial Systems at Airbus. Follows up on the new record. “This very successful maiden flight represents a new significant milestone in the Zephyr program, adding a new stratospheric flight endurance record which we hope will be formalized very shortly. We will in the coming days check all engineering data and outputs and start the preparation of additional flights planned for the second half of this year from our new operating site at the Wyndham airfield in Western Australia.”

The Airbus Zephyr Program

Zephyr UAVs provide “local (as opposed to satellite worldviews) persistence at an affordable price with a re-usable solar-powered aircraft.” Limiting its surveillance to areas hundreds of miles wide, Zephyrs will enable high-resolution visual observation over extended periods.  As Airbus notes, the only civil aircraft that flew at Zephyr’s altitude were the Concorde and NASA’s U2s.  The military had the SR-71 Blackbird.  None of these had the duration to allow day and night observations.

Zephyr T is larger twin-tailed variant that can carry 20 kilogram (44 pound) payload


Airbus has two variants of the Zephyr, designed to accommodate a variety of payloads.

The production model Zephyr S is able to carry see, sense and connect payloads.  In development now, the larger, two-tailed Zephyr T spans 33 meters (108.27 feet).  It weighs 140 kilograms (308 pounds) and can carry a 20 kilogram (44 pound) payload with an even greater range of capabilities.

An interview with Steve Whitby, head of Business Development and Sales explains the current state of Zephyr, its strengths, and the future including that for the larger Zephyr T.  He notes that working with Williams Engineering and its expertise in structures and batteries will enable flights of 30 days with available batteries, and up to 120 days with newer batteries and no changes to the structure.

He foresees building up to 60 Zephyrs in the next year, indicating a growing demand.


Paradoxically, almost every battery breakthrough seems to have an accompanying problem, and battery developers end up sometimes ditching the positive because of an overriding negative.  Solid-state batteries promise some gains without compromise, though.

Conventional lithium-ion batteries have possibly reached the limit of their capacity, some scientists fear, and still remain prone to issues like thermal runaway.  Developers have looked at solid-state battery designs in which even the electrolyte is solid and not prone to bursting into flame.  These batteries promise to have higher energy densities and longer lives, but high resistance at the electrolyte-electrode interface tends to interfere with charging and discharging speeds.

Two groups of researchers at the Tokyo Institute of Technology have been taking different approaches to creating a solid-state battery with improved performance and few of the disadvantages of more conventional lithium cells.

Stacking Battery Components

Scientists from Tokyo Institute of Technology and Tohoku University, led by Professor Taro Hitosugi, “Fabricated all-solid-state batteries with extremely low interface resistance using Li(Ni0.5Mn1.5)O4 (LNMO, or Lithium Nickel Manganese Oxide), by fabricating and measuring their batteries under ultrahigh vacuum conditions, ensuring that the electrolyte/electrode interfaces were free of impurities.”

Researchers used X-ray diffraction and Raman spectroscopy to characterize electrochemical properties of the batteries by analyzing the crystal structure of the batteries’ thin films.  They found “spontaneous migration of lithium ions from the Li3PO4 (Lithium Phosphate) layer to the LNMO layer, which converted half the LNMO to L2NMO at the Li3PO4/LNMO interface.  This migration reverses during initial charging to regenerate LNMO.”

The batteries were made by stacking various layers via thin-film deposition methods. The LNMO/Li3PO4 interface showed spontaneous migration of Li ions and had an unprecedentedly low resistance.  Illustration: ACS Applied Materials & Interfaces

Researchers tested the impedance of the cells using electrochemical impedance spectroscopy.  Resistance “was 7.6 Ω cm2, two orders of magnitude smaller than that of previous LMNO-based all-solid-state batteries and even smaller than that of liquid-electrolyte-based Li-ion batteries using LNMO.”  These batteries also charged and discharged faster, “managing to charge/discharge half the battery within just one second.”  They  also showed “no degradation in performance even after 100 charge/discharge cycles.”

The team’s paper was published in ACS Applied Materials & Interfaces.

Performance of the fabricated all-solid-state batteries.  The (a) charge-discharge curves…

…and the (b) cycling performance plot show that the performance of the fabricated all-solid-state batteries did not degrade after repeated use, demonstrating their excellent stability and the total reversibility of the reactions involved in charging/discharging.

Li(Ni0.5Mn1.5)O4 is a promising material to increase the energy density of a battery, because the material provides us of a higher voltage. The research team hopes that these results will facilitate the development of high-performance all-solid-state batteries, which could revolutionize modern portable electronic devices and electric cars.

Professor Kanno’s Canned Energy

A second group at Tokyo Tech, led by Professor Ryoji Kanno of the Department of Electronic Chemistry, Interdisciplinary Graduate School of Science and Engineering, also works on solid-state batteries.

Currently, Kanno is mainly focusing his energy on the development of all-solid-state batteries, which dispense with the liquid electrolyte that is part of even so-called dry cells.  The organic solvents that act as electrolytes in many lithium batteries are combustible, a big safety concern – especially in aircraft.

Kanno’s all-solid-state batteries “replace organic solvent with solid material, significantly improving safety while making it possible to handle larger amounts of electricity. The travel distance of an electric automobile utilizing this type of battery, for example, can be increased from 200 kilometers (124 miles) to 500 kilometers (310 miles) on a single charge. A more compact design is also possible as all-solid-state batteries do not require the safety devices required for organic solvent.”

Kanno team’s depiction of solid-state battery compared to one with liquid electrolyte

Kanno explains “’Solidity reduces combustibility and increases safety. Furthermore, all-solid-state batteries function over a wide range of temperatures and easily pass current to provide increased power. Quick recharge is also a feature. While all-solid-state batteries have great merits, their one disadvantage is in initiating a contact because, unlike organic solvent, contact requires an interface. If we can solve this problem, the goal of commercialization will be within reach.’”

Following the Money

Commercialization is certainly a part of what is driving Japanese research.  As background, these notes from an article by Bertel Schmitt in Forbes magazine illuminate Toyota’s involvement in at least some of the research being done at Tokyo Tech and elsewhere.

“Solid-state batteries promise to do away with the liquids that caused the build-up of current in batteries ever since Mr. Volta dipped copper plates into brine. Those liquid electrolytes soon became nastier, and sulfuric acid keeps sloshing through car batteries to this very day. “Dry” cells never were completely dry, they use a moist paste that sometimes leaks out. Higher powered lithium-ion batteries can get sometimes way too hot, as the Galaxy Note 7, or the occasional electric vehicle fire can attest.

“Solid state batteries are no fire hazard, they promise to recharge faster, store more power in a given volume, and, especially interesting for automobile engineers, they can be molded into many shapes.

“In 2014, two years after Uchiyamada showed the solid-state-battery-powered skateboard, Toyota engineers presented a solid-state battery that exceeded the energy density of lithium-ion. Work on the solid-state battery continued, and it is continuing.  In 2016, professors at the Tokyo Institute of Technology presented a research paper, saying that the solid-state ‘cells provided high power density, with ultrafast charging capabilities and a longer lifespan than existing battery types.’ Toyota is one of the research partners.”


Coots and e-Gulls at Oshkosh

As many readers know, Richard Steeves, a physician and teacher at the University of Wisconsin – Madison is also a builder and long-time advocate for an amphibious aircraft called the Coot.  He publishes the Coot Builders Newsletter and stages a recurring AirVenture event, a yearly get-together of fellow Coot builders.  Recently, he got into electric aviation and has built and flies Bravo, an e-Gull designed by Mark BeierleRichard’s newsletter now features articles about amphibians and electric flight.

Mark showed up at Richard’s hangar at the Sauk Prairie Airport, a lovely stretch of green bordered by hangars and bisected by a concrete runway pointing south toward Madison and north toward the Wisconsin Dells.

Beierle “worked very methodically and precisely to optimize Bravo beyond my dreams,” according to Richard.

Mark Beierle and Richard Steeves’ example of his e-Gull, Bravo

The Coot Builder’s Newsletter reports, “Mark Beierle showed up at the Sauk Prairie (SP) airport a week before the EAA convention to build a snug-fitting cowling around Bravo’s motor. The idea was to minimize aerodynamic drag and obtain the best range possible for its 11.4 kWh battery.

tufts show clean airflow leading over cowling added by Mark Beierle.  Wing shows absolutely flush riviting that comes with a Beierle-built kit.  Richard adds, “Notice the raised red “brow” over the leading edge of the wing in the center. This was a big insight, and nicely corrected by Mark.”

“To test its effectiveness, Mark flew next to the runway, 3 feet above the grass, while I drove down the runway’s centerline and Mike Cummings took images. Happily, all the yarns streamed back without any flaws. Testing the upper cowling wasn’t as easy, for it required that Mark fly close to me, and take photos from above. At first I was concerned about 2 planes flying so close to each other, but Mark is a superb pilot, and he buzzed around me for the needed images while I flew steadily in stable air.”

Bravo underview photographed as plane flew low down Sauk City runway.  Cowlings under the wing contribute to smooth flow, excellent cooling for motor

“Yes, the airflow over the controller was perfect, and the battery didn’t overheat even with the side “blisters” closing off air access almost completely.

“The only time the battery overheated was in Markesan, with two chargers going in hot weather, and the weather slowed us down there anyway.

Bravo in flight on the trip to Oshkosh

“Mark did all his tests and also flew with me to Oshkosh in an old J-model ICE-powered Soaring Gull that he sold at Oshkosh to a [customer] from Ohio.

“It was great to have Mark flying next to me all the way to Oshkosh. For greatest efficiency and energy reserve, I flew Bravo at 50 mph (8 kW) and landed twice (Portage and Markesan) for recharging, which took only 2 hours at each stop.  …The Portage airport… manager, John Poppy, took good care of us as we waited for rain showers to pass.”

A rainbow over Portage welcomes Bravo

“You can’t imagine how much I appreciated Mark’s presence on the flight to Oshkosh in pretty bad weather…took us 3 days, camping at each stop.

“Also, the approach & landing in the cramped little grass strip in the UL area was challenging for the first time, but was easy once there.”

The Seaplane Base Gathering

Coot Builders’ meeting at the newly-renovated seaplane base drew an appreciable crowd of Coot and e-Gull aficionados

“Although seriously outnumbered by Cooters, e-Gull enthusiasts were also present, including its designer, Mark Beierle, chief assistant Mike Cummings, and a new kit-builder, Ray St. Laurent (NB).

Talk about a car-toppable ultralight!  Ray St. Laurent ready to haul a kit e-Gull to New Brunswick

The day after the Coot meeting we pooled efforts to mount a complete kit onto the top of Ray’s little Pontiac Vibe. He actually made it back to New Brunswick this way with only minor issues. Best of luck building and flying your e-Gull, Ray!”

Perhaps as a vision of a plausible future, Richard says that Mark is considering an amphibious form of the e-Gull, thus combining Richard’s two great loves in flying.


Flow Batteries Aging Well

As previously noted in the blog, the Tissandier Brothers flew their Siemens-powered electric airship in 1883 using a flow battery of their own design for energy storage.  This technology gets a lot of attention for grid-based energy storage, but might have use in more mobile applications.  Nano Flow Cell Technologies in Switzerland, for instance, used different salt waters to power their Quant and Quantino automobiles.

Howard Handelman, a regular reader of the blog, shared the following two researches into modernizing flow cells.  Stanford and Harvard researchers both cooked up different ingredients than one would normally find in a flow battery.  Both groups achieved better than average performance and longevity.

Stanford’s Liquid Metal Approach

Stanford’s battery uses liquid metal that more than doubles the maximum voltage of conventional flow batteries.  Things happen at normal temperatures, unlike flow batteries that need extremely high temperatures.  The metals used are low-cost and non-toxic, unlike the dangerous fluids used in other flow batteries.

Sodium-potassium alloy is a room-temperature liquid metal that could unlock a high-voltage flow battery.  Image: Antonio Baclig

William Chueh, Stanford assistant professor of materials science and engineering, PhD student Antonio Baclig and Jason Rugolo, now a technology prospector at Alphabet’s research subsidiary X Development, used sodium and potassium.  The Stanford press release explains, that when mixed they form a liquid metal at room temperature, which is used as the fluid for the electron donor – or negative – side of the battery.  “Theoretically, this liquid metal has at least 10 times the available energy per gram as other candidates for the negative-side fluid of a flow battery.”

The group found a suitable ceramic membrane made of potassium and aluminum oxide to keep the negative and positive materials separate while allowing current to flow.

The sodium/potassium negative side coupled with the membrane “more than doubled the maximum voltage of conventional flow batteries, and the prototype remained stable for thousands of hours of operation. This higher voltage means the battery can store more energy for its size, which also brings down the cost of producing the battery.”

Stanford PhD candidates (from left) Geoff McConohy, Antonio Baclig and Andrey Poletayev have developed a new type of flow battery that could lead to affordable storage of renewable power. Image : Mark Golden

Baclig adds, “A new battery technology has so many different performance metrics to meet: cost, efficiency, size, lifetime, safety, etc.  We think this sort of technology has the possibility, with more work, to meet them all, which is why we are excited about it.”

He concludes, “We still have a lot of work to do,” said Baclig, “but this is a new type of flow battery that could affordably enable much higher use of solar and wind power using Earth-abundant materials.”

The group published their work in the July 18 issue of Joule.

They continue their work, looking at different membrane and liquid materials.

Harvard’s Organic Flow Battery

And all the days of Methuselah were nine hundred sixty and nine years: and he died.
Genesis 5:27 (King James Version)

Research co-led by Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science, and Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) has helped create a “new organic molecule that outlives and outperforms its predecessors, offering the longest-lasting high-performance organic flow battery to date. Nicknamed the Methuselah quinone — after the longest-lived Biblical figure — this molecule could usefully store and release energy many tens of thousands of times over multi-year periods.”

Methuselah battery should last many years – but probably not 969.  Image: Eliza Grinnell

The abstract for the team’s paper in the journal Joule explains, “…This near-neutral flow battery shows a capacity fade rate that is the lowest of any quinone and rivals the lowest ever reported for any flow battery in the absence of rebalancing processes. This result adds the important attribute of long calendar life to quinone-based redox-flow batteries, which may enable massive penetration of intermittent renewable electricity.”

Michael Aziz explained the significance of the Harvard battery.  “In previous work, we had demonstrated a chemistry with a long lifespan but low voltage, which leads to low energy storage per molecule, which leads to high cost for a given amount of energy stored.  Now, we have the first chemistry that has both long-term stability and comes in at more than one volt, which is commonly considered the threshold for commercial deployment. I believe it is the first organic-based flow battery that meets all of the technical criteria for practical implementation.”

Obtaining more than one Volt from a flow battery is a big breakthrough, but usually means accepting a short-lived energy-storage unit.  Laboratory experiments show the Methuselah molecule had a fade rate of less than 0.01 percent per day and less than 0.001 percent per charge/discharge cycle.  This means less than 3 percent degradation over the course of a year – and years of useful operation.

Potentially safer and, less expensive than lithium-ion batteries and vanadium flow batteries, the Methuselah battery would be a viable alternative for large-scale energy storage.

The research team in their lab. Bottom row, left to right: Daniel Pollack, Emily Kerr, Diana DePorcellinis, Daniel Tabor. Top row, left to right: Marc-Antoni Goulet, Michael Aziz, Roy Gordon, David Kwabi, Yunlong Ji.  Photo courtesy of Eliza Grinnell/SEAS Communications

“This research demonstrates the potential of organics,” said David Kwabi, a postdoctoral fellow at SEAS and co-first author of the paper. “We show that organic molecules are a viable, long-lasting, cost-effective alternative to expensive vanadium batteries.”

“This important work represents a significant advance towards low cost, long duration flow batteries,” said Imre Gyuk, Director of DOE’s Office of Electricity storage program. “Such devices are needed to allow the electric grid to absorb increasing amounts of green but variable renewable generation.”

Merriam-Webster defines quinones as:

1: either of two isomeric cyclic crystalline compounds C6H4O2 that are derivatives of benzene

2: any of various usually yellow, orange, or red quinonoid compounds including several that are biologically important as coenzymes, hydrogen acceptors, or vitamins


Funneling Light and Energy with New Materials

Dr. Adolfo De Sanctis, a Research Fellow in the Quantum Systems and Nanomaterials group at the University of Exeter (UK), earned his Ph. D. in physics with a dissertation on “Manipulating light in two-dimensional layered materials” (Nature Communications, May 2017).  The video below gives a short-hand view of his work.

Other, less scholarly outlets (like this one) give an easy-to-read view of what he has accomplished, and why his research is of interest for many applications – including energy harvesting.

Green Optimistic reports, “A team of researchers from the University of Exeter developed a solar cell with a record 60% efficiency. The idea behind this breakthrough is similar to using a ‘funnel’: corralling an amorphous collection of electrical charges into a more precise area, where they can be transferred into use. Using this idea, the researchers increased the efficiency of a solar cell from 20 to 60 percent.  The Exeter team sees their research as a ‘gateway’ for further research and development.”  That means any practical applications are more than the popular “five years away.”

Inverse charge funneling in strained HfS2.  Somewhere north of your editor’s pay grade, the Nature Communications article explains, ” The compression induces tensile strain away from the HfS2/HfO2 interface, resulting in the spatial modulation of the bandgap. b Ab initio calculations of the valence band maximum (VBM) and conduction band minimum (CBm) of 1T-HfS2 as a function of strain in the Γ → Γ (direct gap) and Γ → M (indirect gap) directions. c Change in bandgap as a function of strain in the two directions, with respect to the unstrained bandgap (relaxed lattice constant a0 = 3.625 Å). Inset: calculated band structure of 1T-HfS2″

Solar-powered cars, aircraft or boats could be smaller, without the need to add area for solar cells.  Airplanes could be more efficient and faster, or add range and endurance in their existing size.

De Sanctis’ team created a 2D material with a graphene base and added a new material – hafnium disulfide.  This enables the graphene/hafnium material to stretch and compress in ways that would rip ordinary materials apart.  The enhanced materials can sustain a 25-percent level of stress compared to a puny 0.4 percent for conventional materials.

Applying this to solar collectors, photoexcited charges can be funneled away from the excitation region and towards areas where they can be efficiently extracted.

The abstract for the team’s paper in the journal Nature Communications concludes on this hopeful note.  “These results open the route towards the exploitation of strain-engineered devices for high-efficiency energy harvesting and sensing applications, with the potential to overcome the intrinsic limitations of current solar cells by exploiting both hot-carriers extraction and lossless transport, to achieve efficiencies approaching the thermodynamic limit in photovoltaic devices. The use of atomically thin materials could open the door to the incorporation of such devices in emerging wearable electronics technologies and smart buildings, creating a new paradigm in energy harvesting.


Icarus Cup Achieves New Records

Doing more with much less, British pilots at this year’s Icarus Cup follow in Paul MacCready’s aerial path, staging a highly successful weeklong demonstration of human-powered flight.  Airplanes that fly on about a quarter-kilowatt for as long as the human battery can operate the pedals are not new, and significant records have been achieved over the years.

The British have long been involved, beginning with the 590 meters flight by Derek Piggott on November 9, 1961 in SUMPAC (Southampton University’s Man Powered Aircraft – note the sexist terminology of the day).  This was considered the first authenticated takeoff and flight by a human powerplant.  He made 40 flights before suffering a crash that damaged a wing.

To help foster interest in human-powered flight, The Royal Aeronautical Society formed the Man Powered Aircraft Group in 1959.  Henry Kremer, an industrialist, set up the Kremer prize for a figure-of-eight flight around two markers half a mile (~0.8 Km) apart in 1959.  It took 18 years for Brian Allen, pedaling Paul MacCready’s Gossamer Condor to win that prize.  Two years later, he guided the Gossamer Albatross across the English Channel, winning the Cross Channel Kremer Prize.

Others have since flown even longer distances, but the sport has struggled in Europe and America for the last several decades.  The Japanese have created a fairly thriving group of builders and pilots who are approaching the cross-channel distance records.  An international competition might bring money and enterprise into sharper focus.

The rules for this year’s contest  organized by the British Human Powered Flying Club provided for the following tasks:

1) Duration

2) 200m time trial

3) 1km time trial

4) 500m slalom course

5) Distance around a triangular course (based on a 1.5 kilometer – 0.93 mile perimeter)

6) Unassisted takeoff performance

7) Landing accuracy

8) Takeoff from grass

9) 200m time trial with takeoff from grass

10) Jacobson Figure of Eight (with turn points 350 meters – 1,150 feet apart)

Emulating last year, four teams showed up, but only two actually competed – but fiercely.  Nial Paterson flew the first successful HPA figure of eight in Britain, going around the course one and a half times before making a great landing.  As the video-maker notes, “This isn’t just the first time this flight has been flown in the UK, it’s probably only the second or third time a full figure-of-eight has been flown in any HPA anywhere in the world.”  In other words, it’s harder than Niall Paterson makes it look.

Fred To, a long-time leader in human-powered flight, wrote to your editor, “ A good friend of mine donated some money to us and asked me to design a course for a new prize , so I and John McIntyre came up with a tight figure-of-8 course. Well, the constructors of the aircraft knew that this time they had to have good cyclist/ pilots to fly these aircraft. A great guy Niall Paterson just flew the circuit the first time around and made history, as that was the first time a figure-of-8 had been flown in this country, and it was a much tighter course than ever before with pylons set 350m  apart. In fact, the course could be tightened future to 300m or even 250m in later competitions.”

Winning scores went to the newer Aerocycle 103 and the Airglow, an “experienced” HPA flying since 1989.

The BHPFC-RAeS Team Cash Prize Scoreboard
1st Prize : – Aerocycle3 total 10790 points

Best Duration 1204
Best 200m 1166
Best 1km 1646
Best 500 Slalom 2200
Best Triangle 1000
Best Unassisted t/o 1199
Best Landing Accuracy 468
Best T/O Grass 1249
Best 200m T/oG 658

2nd Prize : – Team Airglow total 6943 points
Best Duration 973
Best 200m 674
Best 1km 1124
Best 500 Slalom 1400
Best Triangle (DNS)
Best Unassisted t/o 985
Best Landing Accuracy 199
Best T/O Grass 1319
Best 200m T/oG 269

Individual pilots racked up points flying the two competitive machines.  One remarkable (to this editor) achievement was 11 reversals in a 500 meter (1,640 feet) slalom event.  This shows a level of control perhaps as tough as that required for the figure of eight.

The RAeS Icarus Cup Trophy results for pilot performance at the BHPFC Sywell Competition 2018.
Niall Patterson 9802 pts (Aerocycle)
Lewis Rawlinson 9055 pts (Aerocycle)
Kit Buchannan 7571 pts (Aerocycle)
Mara Jennings 5666 pts (Aerocycle)
Reuben Arkwright, 5321 pts (Airglow)
John Boyce, 2080 pts (Airglow)
Mike Truelove 2060 pts (Aerocycle)
Robin Kraike, 1749 pts (Airglow)
Ioan Hill, 1514 pts (Airglow)
Alec Proudfoot 1312 pts (Aerocycle)
Zak 1122 pts (Aerocycle)
Sam Morley, 341 pts (Airglow)
David Clarke, 294 pts (Airglow)

As reported in the Northampton Chronicle & Echo, “Team Airglow pilot John Boyce has been flying for more than 30 years and is competing this week – he said: ‘You have to drive it with your legs, every ounce is critical, the aircraft is experimental, it’s unpredictable, they’re incredibly affected by changes in wind and weather.’”

Lewis Rawlinson in cockpit of Aerocycle 301. Photo from Northhampton Chronicle & Echo

“John added: ‘You can’t get a lesson. If you get a flying lesson you sit next to an instructor for an hour but you get into this for your first flight, on your own, and have about five seconds to learn how to fly it, all the while peddling to the absolute limit of your physical endurance.’”

Further afield, a newspaper in Washington state headlined, “Local couple’s nephew part of ‘Icarus Cup’ competition.”  Karen and Clay Parsons’ nephew is Alec Proudfoot, designer of the DaSH Project PA, which has flown at Half Moon Bay and Moffett Field, California.  Heading the Aerocycle 301 team, he carried America’s capabilities to England.

The Islands Sounder added an interesting note about Alec’s engineering career.  “Proudfoot and his team are based in Palo Alto, California. He was also one of the designers of the first electric car, the EV1, produced by General Motors and the lead engineer on the electric car team at Google before his retirement. He now works as an independent inventor.”

The (Wiltshire) Gazette and Herald added information about Aeroglow’s designer.  “John, of Huntingdon Street, Bradford on Avon, said: ‘This is a fascinating event trying to get a human-powered aircraft to take off and fly in multiple challenges for the trophy.

Airglow disassembled in hangar and doing some “hangar flying”

“‘You have about five seconds to get a feel for the controls and the aircraft response, then fly it with minute control, compensating for wind changes, all the while pedaling at your absolute maximum power output.

“‘The aircraft is incredibly unpredictable and vulnerable to any changes in wind speed and direction and you have to make split-second decisions.

“‘You control the aircraft with a tiny electronic joystick, while making judgments and pedaling furiously to the limits of human endurance.

“‘The Airglow team was second overall last year and we were hoping to take the trophy this year but it wasn’t to be.’”

With an American win this year and a creditable performance by a 30-year-old second-place winner, one wonders if the inclusion of Japanese teams would bring greater recognition and the aura of worldwide competition to the event.

Fred To (left), writes, “The announcer of the Japanese birdman rally, Masato Suzuki, is a friend of mine and he just happens to be the managing director of Yamaha bikes in the UK, he came up and visited us and was amazed at the progress made with designs. Masato had been involved with HPAs since his days at Nihon University and is a great guy.”  Friend on right is identified as “Jesse.”

Thanks to Fred To for his contributions to HPAs, and to Chris Roper for his ongoing chronicling of these fantastic machines.  Fred has ties to a Japanese HPA follower who might be able to help make next year’s event truly international.


Riding the Sunshine Highway

Sunday, July 22 found your editor at Bend, Oregon’s High Desert Museum for the finish of the 2018 American Solar Challenge.  The race started in Omaha, Nebraska on July 14 and followed parts of the Oregon National Historic Trail and the Lewis and Clark Trail.

  1. Omaha, NE (Starting line) – July 14
  2. Grand Island, NE (Checkpoint) – July 14
  3. Gering, NE (Stage stop) – July 15 – 16
  4. Casper, WY (Checkpoint) – July 16
  5. Lander, WY (Stage stop) – July 17-18
  6. Farson, WY (Checkpoint) – July 18
  7. Arco, ID (Stage stop) – July 19 – 20
  8. Mountain Home, ID (Checkpoint) – July 20
  9. Burns, OR (Stage stop) – July 21 – 22
  10. Bend, OR (Finish line) – July 22

American Solar Challenge route followed parts of the Lewis and Clark Trail and the Oregon National Historic Trail

Teams came from colleges and universities all over the world.  Six of the single-occupant vehicles (SOV) and one multi-occupant vehicle (MOV) managed the entire 1762.7 miles without breakdown or significant mechanical difficulties.  Considering the cars had to make it over the Rockies, and scale a 902 meter (2,958 foot) climb in only 35 kilometers (21.7 miles), between Lander and Farson, Wyoming, the number that made it across the finish line is impressive.

Rough numbers show the number one Sydney Team made the 1795 mile trek in 37 hours and 55 minutes – averaging over 47 mph across western America.  Given the rising nature of the terrain for most of the trip, the lead car made it in no more time than a typical family journey complete with gas stops, potty breaks, etc.

Cheers and Hospitality

Your editor and his friend Mary Maxwell were privileged to meet some of the drivers and support team members.  One of the most enthusiastic was 84-year-old Chuck Hutchins, number 1 cheerleader for the Michigan team.  A long list of testimonials thanking companies that supported the University of Michigan’s Novum team includes a heartfelt tribute to Chuck, a U of Michigan graduate in mechanical engineering who went on to co-found Manufacturing Data Systems, Inc.  He doubtless shares a wealth of knowledge as well as enthusiasm in mentoring the team.

University of Michigan’s Number One cheerleader, Chuck Hutchins, in semi-formal splendor

Unlike many events which enforce a strictly hands-off approach to viewing the competing vehicles, ASC teams invited us to “try on” the multi-occupancy vehicles.  Urged to sit in Iowa State’s prISUm MOV, we discover that it’s quite roomy, has a great sound system (belting out Neil Diamond at that moment), and a huge “infotainment” screen in the center of an otherwise austere dashboard.  Drivers and passengers could be excused for wanting to flood their senses with sound while driving without air conditioning across desert terrain.  Even though it did not qualify in the event, it ran strongly and won Anthony Dekker’s (see below) approval as the Most Desirable Car.

Iowa State MOV, despite being disqualified, was a highly-desirable ride

Many parts, although made from aluminum and other lighter metals (the whole car weighs a mere 1,100 pounds) seem massive, perhaps an outcome of its farm country heritage.  John Deere, along with other major players, sponsors the team.

An Instructive Blog

Your editor was able to follow the Challenge on a blog called, “Scientific Gems, Facts, ideas, and images from the shoreline of science.”  It had detailed daily updates and knowledgeable insights into the event.

Anthony Dekker’s chart consolidating data from the overall Challenge

Editor Anthony Decker seems to be as much a fanatic about following solar racing as your editor is about following electric aviation.  A significant difference is that “Tony” publishes some pretty daunting items such as “Conceptual Distance in Social Network Analysis,” in the Journal of Social Structure, and “Applying Social Network Analysis Concepts to Military C4ISR Architectures,” in Connections, the official journal of the International Network for Social Network Analysis.

Final results, including practicality scores for MOVs

Thinking about Solar Flight

These cars, capable of hitting highway speeds and conquering the Rockies, are precursors to future designs.  Their incredible lightness shows a recognition of what can be achieved with modern materials.  Their comfort, in the MOV class, shows this technology can also be applied to a realistic road vehicle.  Can the lessons continually learned by these solar road warriors be of use in the sky?  Your editor thinks yes, and hopes for further progress in this realm.


John Goodenough’s Counter-intuitive Battery

A Long and Productive Life

On his 96th birthday today, John Goodenough and his research team’s latest findings are the subject of much speculation.  He, fellow scientist Maria Braga, and his research team have created a battery claimed to be three times as energy dense as existing lithium-ion contemporaries, but exhibiting the counterintuitive property of improving with repeated charging cycles.

Goodenough’s career began in 1943 (a year after your editor was born) with the award of his bachelor’s degree in mathematics from Yale University, followed his master’s and Ph.D. in physics from the University of Chicago in 1951 and 1952 respectively.  He worked at MIT and in 1976, left to become head of Oxford University’s Inorganic Chemistry Laboratory from 1976 to 1986.  In 1986, he assumed the Virginia H. Cockrell Centennial Chair in Engineering at the University of Texas at Austin, at an age where most men are cashing in their 401k’s.

Texas Monthly comments on the counterintuitive nature of the man himself.  “And yet, he’s a bit of an anomaly in the research world. For one, ‘I use chemistry to answer physics questions,’ he says. Also, he sees a connection between his scientific pursuits and his Christian faith: ‘If you believe that there’s a creator, you should show respect for that creator by respecting his creation. Scientists show respect for creation by studying our planet and how it works. They serve people with their discoveries.’”

John Goodenough’s  2017 95th pre-birthday party in the Maker Studio at the Cockrell School of Engineering – photo taken on June 30, 2017. His actual birthday is on July 25.  Photo by Marsha Miller

The University of Texas writes of his accomplishments, “In 1979, his discovery of the lithium-ion battery dramatically shaped the world of consumer electronics. These rechargeable batteries are now used by millions of people every day to power consumer electronics as diverse as cellphones, tablets, cameras and tools. You are probably holding one right now.”

Eric Schmidt, Executive Chairman & former CEO of Google, and Elon Musk, head of a large electric car company, have both lauded Goodenough’s work.

The Paper

“Nontraditional, Safe, High Voltage Rechargeable Cells of Long Cycle Life,” published in the April 24, 2018 issue of the Journal of the American Chemical Society, hides a great deal of promise behind a humble title.  Co-authors Maria Helena Braga, Chandrasekar M Subramaniyam, Andrew J. Murchison, and John B. Goodenough share honors for this potentially exciting revelation.  (Cautionary note: other researchers seem to be expressing a great deal of skepticism about this research, although honoring Goodenough and Braga’s demonstrated skills as researchers.)

Why is it exciting?  First, the battery has gone through over 23,000 cycles.  Most researchers seem to announce results after a hundred or so cycles, avoiding the issue of how their cells will hold up long term.  Second, the battery gains specific capacity (milliamp hours per gram) as the number of cycles increases.  Normally, batteries lose storage capacity as they are used.  Since the 23,000 cycles would allow a charge/recharge cycle every day for 63 years, this is essentially a lifetime battery.  Third, there is no cobalt, expensive and with the market cornered by China.  It’s replaced by more common, less expensive materials.  Fourth, it’s a solid-state battery, with no liquid electrolyte to ignite.  Fifth, it charges in quick-time, much like a capacitor.

That controversial rise in capacity with an increasing number of cycles. Where will it end?

The so-called “glass battery” has several areas of controversy, as listed an article in Axios.  Its high “relative dielectric constant,” a measure of energy storage in an electrical field, is higher than any recorded for a material.  Axios says the paper apparently does not make clear whether an unplugged battery of this type will hold its charge for any significant time, although parts of the JACS paper seem to address this.   The battery’s ability to increase capacity through repeated charging elicits the most skepticism, expressed by six battery scientists contacted by Axios.

Researcher Maria Helena Braga works on the glass electrolyte for the new battery. Doped with lithium or sodium, the glass electrolyte allows the battery to be recharged within minutes instead of hours.

Maria Braga responded to the criticism in a follow-up to the article.  “Data is data and we have similar data from many different cells, in four different instruments, different labs, glove box. And at the end of the day, the LEDs are lit for days with a very small amount of active material after having cycled for more than 23,000 times.”  (The “glove box” reference is not explained.)

Goodenough’s contributions are found in virtually every lithium battery today.  Even though he’s often mentioned as a potential Nobel Prize winner, his efforts have rarely given him substantial financial compensation.  His determined outlook and happy disposition seem to be their own reward, though, and his research continues.  He foresees his latest creations achieving commercial status in the next two years.  Let’s hope he’s right.


Rolls-Royce Rolls a Few New Approaches

Rolls-Royce, famous for building engines such as the WWII Merlin that powered Spitfires, Mustangs, Mosquitos and Lancaster bombers, is engaged on three (or four) fronts currently, bringing hybrid electric transport to the skies.

Hybrid Electric VTOL for Commuting

Rolls is jumping into this crowded market segment with its concept for an electric VTOL (Vertical Takeoff and Landing) machine, powered by four electric motors on the wings and two on the tail.   With over 100 machines of varying configurations that might be the Uber rides of the future – according to Electric VTOL News, Rolls, normally a conservative company, is planning something a bit radical – even in this field.

Longer range, higher speed distinguishes Rolls-Royce eVTOL from competing urban cruisers

Rolls’ headline for this craft indicates a new direction for the firm: “Quieter, cleaner and potentially disruptive: EVTOLs prepare for take-off.”  Launching at Farnborough this month, Rolls’ machine and its goals are best described in their launch publicity.  “Rolls-Royce’s hybrid EVTOL concept is based around the M250, the engine of choice for roughly 125 types of fixed-wing aircrafts and helicopters. Used in both civil and defense applications, it’s logged 250 million flight hours over the past half-century. By adding an electrical generator, the M250 becomes part of a hybrid-electric propulsion system that can power a 4 to 5 person vehicle capable of traveling at 250mph over a range of 500 miles or more. The gas turbine generates 300-400kW of electricity while a battery system (making this a series hybrid system) can provide an additional 300-400KW for hover.”

Note the use of 50-year-old, but obviously well proven, turbine as a token to Rolls’ conservatism.  Note the proposed high speed and long range and realize the company wants to take eVTOLs to the next level.

ACCEL – a Twin-Motor, Contra-Rotating Propeller Machine for Racing

Started by TEACO (The Electric Aircraft Company) in 2012, and supported by Williams Engineering, known for its Formula 1 automobile racing acumen, ACCEL flies on twin YASA motors developed at Oxford University.  It progressed from a single propeller to twin contra-rotating props, and has been adopted by Rolls-Royce to be “the centerpiece of Rolls-Royce’s ACCEL (Accelerating the Electrification of Flight) initiative.”

A high-speed melding of technologies from ElectroFlight, Williams Engineering, YASA Motors, and Rolls-Royce, ACCELL prototype should fly by 2020

Matheu Parr, manager of the ACCEL project for Rolls-Royce, explains,“It’s truly a global project, integrated across regions and skillset,” and will be supported by Electroflight Ltd (UK).

Roger Targett, Managing Director, Electroflight says, “We are delighted to be supporting Rolls-Royce with an integrated electric powertrain including an innovative energy storage solution.”

Chris Harris, CEO, YASA adds. “Thanks to our innovative axial-flux design, YASA can deliver the smallest, lightest electric motors for a given power and torque – opening up new and exciting opportunities for electrification in aerospace.”

Rob Watson, Director of Electrical, Rolls-Royce sees broader horizons growing from this project.  “We are delighted to be leading this research partnership. We are already investigating the potential of hybrid-electric propulsion, building on our existing expertise in applications such as hybrid trains and gas turbine-powered naval vessels, but this funding from the UK Government will enable us to explore the potential of all-electric flight.

E-Fan-X for Short Airline Hops

As reported here last year, Rolls-Royce is working with Siemens and Airbus to adapt a BAE 146 light airliner to electric hybrid power for regional air transportation.  Using an existing airframe to test their replacement of one of the 146’s jet engines with an electric generator will speed up development, with the hope of meeting Rolls’ ambitious goal to achieve first flights in 2020.  This project seems like competition for Boeing’s Zunum program, with similar timelines but different configurations – Boeing starting with at least two “clean-sheet” designs.

And Maybe a Sporty Toy for the One Percent

Most surprising, and maybe just a bit apocryphal, Rolls and Aston-Martin released renderings of their joint project – a luxury machine with similar performance to Rolls’ commuter eVTOL, but a far swoopier look and the kind of machine towards which GQ and the Robb Report will direct one’s gaze.


Peter Sripol is a high-energy model-airplane tester who put a twin-motor electric biplane together out of Home Depot/Lowes parts and flew it successfully.  That was a back of the envelope design that flew nonetheless.

Peter did something a little more professional for his second go-round, crafting some professional-looking drawings.  Don’t look for any drawings for the earlier machine, he cautions, explaining there are none  He also wanted a pair of larger, slower turning propellers to move a large volume of air more slowly than the Rotomax 150s installed on the biplane.  He notes he’s looking for a lower kV (turns per Volt input).

Peter works with Flite Test, a model airplane outfit seemingly willing to try anything.  That includes the giant cardboard twin-motored craft shown above.

He apologizes for not being further along on the project, but notes he took time out to build a tank(!) for a video-game client.  Let this be a rebuke to those who claim they don’t have enough tools in their workshops.  Peter’s neighbors might be excused for being a bit nervous about his Fourth of July celebration.

He gets the airplane outside, only to speculate on whether the gear is strong enough for even his light pilot weight.  In literary criticism, we’d identify this as foreshadowing, a device for letting the reader or viewer know something important’s going to happen later in the narrative.

His third video begins with the collapse of his landing gear, with a flashback to show the airplane’s wing construction and a lead-in to how this sad event came to be.

Flite Fest 2018

Here, we get a close-up of the motor, a Tiger Motor (“The Safest Propulsion System”) U15 made in China and rated at 100 rpm per Volt.  Weighing only 3.4 pounds it puts out 77 pounds of thrust with a 40″ prop.  It cranks that out at 3,543 rpm at around 60 Volts and 115 Amps if my math is correct.  The motors are $689 each and the props come as a clockwise/counterclockwise set for $448.  Peter may beat your editor on cheapness.  The company doesn’t seem to have a 200 Amp ESC, though, so it must be another firm’s controller involved.

We’re looking forward to Peter getting his Mark 2 back on an improved gear and flying safely.  His example shows that enthusiasm, hard work and a wildly optimistic outlook can accomplish almost anything.