Meet Airbus E-Fan

Disrupt or be disrupted. It's one of the hard lessons emerging in today's tech-fueled economy, in which the frenetic pace of innovation means not only seeing new ideas materialize with dizzying speed but also watching as they threaten to obliterate entire industries that came before them. We've glimpsed this trend in aviation already with everything from old-school radios to paper charts as a number of smart and tenacious newcomers — names like Garmin, Avidyne, Aspen and ForeFlight come to mind — have turned bright ideas into successful start-up business enterprises.

More disruption, we are told, lies ahead. If you're an airplane manufacturer still turning out products first conceived of in the 1940s or 1950s — and you don't have anything revolutionary in the planning stages — the time to panic is now.

It's appearing increasingly likely that the next wave of disruptive innovation will come from Europe at the hands of Airbus Group, which has formed a subsidiary called ­VoltAir SAS in France to build a family of plug-in and hybrid-electric light airplanes. The plan figures to play a key role not only in recalibrating how we look at light aviation but also in shaping the future direction of the world's second largest airplane manufacturer.

VoltAir's immediate aim is to build a factory in the south of France and begin producing the ­E-Fan line of small airplanes, beginning with a two-seat trainer called the E-Fan 2.0, powered entirely by batteries and electric motors and slated to reach the market in 2018. A follow-on, hybrid-electric four-seater called the E-Fan 4.0 targeted primarily at buyers in the United States will emerge soon after and is projected to go on sale in 2019.

Welcome to the Future

Different doesn't begin to explain the approach to designing and producing these airplanes. The shapes are all new; the electric motors are new; the ducted variable-pitch fan propellers are new. The engineers will take advantage of the latest carbon-­fiber design techniques with never before tested aerodynamic shapes. It's all made possible by the aesthetic freedom electric motors give to the engineering design team, since the motors can be placed just about anywhere on the airframe.

Airbus' real aims with VoltAir and the E-Fan family of airplanes, however, are far more ambitious than merely producing electric airplanes for an admittedly limited general aviation market. The prolific maker of commercial airliners is instead laying the groundwork for a tomorrow that could include fleets of ­futuristic-looking hybrid-electric airliners under the Airbus E-Thrust project. They'll be capable of whisking 100 or so passengers on short-haul flights of perhaps 1,000 miles. Designs for even bigger planes with farther reach are in the works. It's staggering stuff.

Before any of these ambitious goals can be realized, though, planners at Airbus know they first need to take the small steps that will incrementally bridge the technological gaps necessary to make a battery-powered hybrid-electric airliner feasible.

Some of these steps are being undertaken already. VoltAir has formed a partnership with engineering conglomerate Siemens of Germany to produce the power systems for the small E-Fan battery-powered and hybrid-electric production models. If the companies are successful with this first stage, they envision expanding their cooperation to tackle the hybrid-electric drive systems for much larger airplanes, which could become a reality within the next couple of decades.

Airbus Group is also enlisting ­Daher, maker of the TBM 900 turboprop single, to produce the E-Fan 2.0 and 4.0 models at the new factory in Pau, France, near the Pyrenees Mountains on the border with Spain, construction of which is scheduled to start next year. Daher will also play a key role in marketing and selling the VoltAir models through its established dealer network.

The big question at this point is whether the GA market will really want to buy and own electric airplanes. Nobody knows. Airbus' success will depend largely on the utility, performance and safety of electric airplanes, not to mention their price. Done right, E-Fan could be just the boost general aviation needs to succeed and thrive for many years to come.

Dawn of Electric Flight

Preliminary data looks promising. Airbus tells us the E-Fan 2.0 trainer will incorporate two main electric motors connected to two multirotor shrouded fans with enough battery power to allow flight lessons of perhaps 40 minutes (plus reserves) confined mainly to the traffic pattern and practice areas near the airport.

As soon as one lesson ends, the E-Fan 2.0's depleted battery packs can be removed and fresh packs slid into the wing in their place so the next lesson can begin. Meanwhile, the old batteries are plugged in for recharging. Fully charging a set of depleted battery packs is expected to take a few hours, so multiple battery packs would be required at busy flight schools.

As exciting as this all sounds, the really big news is what Airbus has in store for general aviation pilots in America. The E-Fan 4.0 will be powered by bigger electric motors and fitted with a single piston engine producing perhaps 200 horsepower. The engine (probably a compression ignition diesel burning jet fuel) won't directly drive the propellers but will instead be used in cruise flight to power an electric generator that will supply power to spin the fans and keep the batteries fully charged.

The idea is to be able to offer an airplane with similar performance to that of today's gasoline piston offerings but which would burn 25 to 50 percent less fuel. Purchase price is targeted to be close to those of current GA piston airplanes like the Cessna 172 (so somewhere in the range of $400,000) with smaller fuel bills theoretically tilting the economics in favor of the hybrid-electric approach.

As envisioned, the E-Fan 4.0 would use pure battery power for takeoff and climb, taking advantage of the ample torque of its electric motors to launch the airplane to cruise altitude without burning an ounce of liquid fuel. Climbing away from the runway in near total silence would also serve to appease airport noise critics, an important consideration in Europe and an increasingly important one in the United States as well.

Once airborne, the computers would switch on the piston engine, enabling flight of three hours or so at a cruise speed of perhaps 150 knots as the onboard electric generator powered the motors and kept the batteries topped up to allow for the possibility of a quick-turn departure after landing, if desired.

A New Way of Thinking

Airbus first publicly broached the topic of electric-powered flight five years ago, in 2010, when it brought an electric-powered Cri-Cri single-seat airplane to the Paris Air Show. Nobody knew then what to make of the little contraption with its electric motors whirring furiously to propel it into the air. Most who saw it pointed and laughed.

Next, Airbus publicly introduced the VoltAir name in 2011, announcing plans for future electric-­powered airliners. This time the world mostly scoffed, with some in aviation (nudge, Boeing) dismissing the idea as a flight of fancy.

In the time since then, however, few still doubt the lofty aims of Airbus Group and its project partners as they make it abundantly clear just how serious they are about advancing electric-powered flight.

Shortly after forming VoltAir, Airbus partnered with Diamond Aircraft of Austria to build an electric-powered proof-of-concept using a Diamond motorglider airframe and small electric motor supplied by Siemens. Work on the first E-Fan prototype started at around the same time. By the time Airbus began demonstrating the E-Fan 1.0 prototype at airshows in Europe last spring and announced plans for production models, nobody was laughing. Suddenly, the question wasn't if a fully certified production electric airplane from Airbus would materialize, but rather when.

Unquestionably the E-Fan proto­type is a revolutionary design. Packs of lithium-ion batteries fitted into its wings are the sole power source for the E-Fan 1.0's two 30 kW electric motors driving thin blades inside tiny nacelles that give the airplane a jetlike appearance. The demonstrator has two retractable wheels fore and aft and two more under the wings. A separate 6 kW electric motor connected to the rear main wheel provides extra oomph for takeoff acceleration, which reduces electrical power burden on the main motors on the ground.

Because of the limited power density of current lithium-ion batteries, the E-Fan 1.0 has less than an hour's flight endurance. To address the concern of range anxiety, the airplane is outfitted with a backup emergency battery with enough power to allow the pilot to choose a suitable landing site. In the production version there will be a backup battery as well as a whole-airframe parachute that can be deployed if all the batteries are drained in flight. Like in electric cars, a power-level gauge informs the pilot as to how much energy remains in the batteries.

The production versions of the E-Fan are sleeker-looking designs than the prototype and include tricycle landing gear, modern automotive inspired interiors and a number of other innovations currently in the works. A key technology on the ­E-Fan is its E-fadec energy management system, which automatically handles power loads for the electrical systems. This greatly simplifies system controls, easing the workload of future E-Fan pilots.

"It's a totally different approach to flying," says Airbus chief technical officer Jean Botti. "The computers handle everything for the pilot. Everything is simplified. There is no noise, no emissions."

Unlike in the prototype, electric motors probably won't drive the wheels on the ground for taxi and takeoff in the E-Fan 2.0 and 4.0. Airbus is developing the avionics in-house, and you can be sure the E-Fan family will incorporate the very latest in glass-cockpit touchscreen technology with an array of situational-awareness and other safety tools.

Airbus plans to break ground on the E-Fan factory at Pau Pyrénées Airport next spring. The site was chosen for its proximity to Daher, based in nearby Tarbes, France, and the perennial good weather that will enable the E-Fan development team to take maximum advantage of the accelerated test flying schedule.

The VoltAir team is now busy building the E-Fan 2.0 proof-of-­concept airplane, which is expected to fly next year. The first production E-Fan 2.0 is scheduled to make its first flight in 2017. Both the 2.0 and 4.0 will have twin fans and electric motors, T-tail, canopy and winglets.

The certification timeline of the models is important. Airbus wants to bring the products to the marketplace as quickly as possible to give them a head start on the competition. A number of different companies are developing electric airplanes, most notably Pipistrel in Slovenia and Aero Electric Aircraft Corp., the brainchild of electric airplane proponent George Bye. Airbus is in a race to be the first to enter full-scale serial production of an electric airplane. It is a race the company intends to win.

Certification Hurdles

It won't be easy, though. At the annual CAFE Foundation symposium in Santa Rosa, California, this spring, around 170 of the electric airplane world's smartest minds came together to discuss the future of battery- and solar-powered flight. The mood was upbeat, and nearly everybody there seemed to agree that the dawn of electric flight is upon us.

There is a starting gun of sorts in this race, however, and it's the FAA's rewrite of Part 23 light airplane certification regulations, which was supposed to have been finished by now. The agency is busily crafting a notice of proposed rulemaking for this transition, which aims to allow new technologies like electric airplanes to reach the market faster while also cutting the cost of certification in half.

As the rules are written now, Airbus, or anyone else, could never hope to create something so revolutionary as the E-Fan 2.0 or 4.0 because certification regulations were crafted many decades ago, when airplane models from the 1940s and 1950s still seemed fresh and new.

The revised regulations, expected to appear in NPRM form by the end of the year and go into effect in 2017, will presumably make allowances for the inclusion of battery power and for the use of two small electric motors in place of one large piston engine. Plenty of questions remain, however. Will a student pilot learning in an E-Fan 2.0 earn a multiengine certificate? Or will new pilot certification classes need to emerge? Will a pilot who learns to fly in an E-Fan 2.0 be able to fly a Cessna 172 without additional pilot certification? The FAA will grapple with questions like these and many more as the disruptors of the world continue doing what they do best.

The disruptees, meanwhile, might want to consider a different approach. After all, there's little chance that what has worked for the last 50 years will continue working for the next 50 — or even the next 10.

Botti signed on as chief technical officer at Airbus Group in 2006 after spending most of his career in the automotive industry. It will be his job to ensure that the E-Fan family of products emerge on the ambitious time schedule Airbus has announced while also meeting key performance and price targets.

The tight schedule might seem impossible, but Botti said engineers at VoltAir have been involved in certification efforts with regulatory authorities in Europe since day one.

"We have already started the technical work that will lead to certification with the DGAC [the French civil aviation authority]," he said. "Our colleagues at Airbus North America have also begun discussions with the FAA."

Whether E-Fan becomes a bonafide business is still something of a question mark, even Botti admits. "E-Fan is a learning tool," he said. "The expectation is to be able to get to the point where we can do volume production, but it's very important to note that our real aim is to be able to produce hybrid-electric regional airliners."

Still, he said, the advantages of an electric-hybrid approach to light general aviation, meaning everything from reduced noise and lower cost to lessened environmental impact and better efficiency, should make E-Fan a compelling choice for airplane buyers.

As you might suspect, there will also be some radical changes in the E-Fan cockpit. While it's unlikely we'll see fly-by-wire technology or automatic thrust capability come

to the E-Fan 2.0 and 4.0, the approach to designing the computer brains of these airplanes is very different as well, and in a good way.

VoltAir engineers are developing the E-Fan cockpit with considerable input from ENAC, the French civil aviation school, which expects to buy a fleet of E-Fan 2.0 trainers. The overarching philosophy will be a focus on user friendliness, enabling flight planning tasks to be carried out with a few taps on the screens, checklists to be more automated and emergency scenarios to require far less input by the pilot as the computer software of the system handles the majority of time-critical tasks.

It's an idea that has already taken root in the airline and business jet realms, where cockpit automation is routinely put to maximum effectiveness. Which begs the question: Will E-Fan be a pilot's airplane or instead something only a systems manager could love?

If Airbus can succeed in giving the world a family of light airplanes built for the 21st century, at competitive prices, while keeping some of the attributes we can't live without, this big bet could very well herald general aviation's future.

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