Will 2015 See Deliverable Electric Airplanes?


When I was a little kid riding in my Dad’s Oldsmobile across the plains of Texas at night, we would spot the lights of Amarillo in the distance and two hours later, we’d get there. An exaggeration of course, but it reminds me of covering the electric airplane industry.

We’ve reported periodically about this company or that, this new battery development or breakthrough motor controller yet…nothing. I visited Europe twice last summer with a topline agenda item of actually flying an electric airplane. Almost accomplished it in Slovenia, but got blown out by the bora winds common in that part of the world.

This spring, however, the first electric airplane you can actually buy looks like it will emerge at Aero in Friedsrichshafen next month. It will be announced by—who else?—Pipistrel, the innovative Slovenian company that’s been bullish on electric flight for several years and five projects. They’ve been selling an electric motorglider which is now just beginning to get some sales traction. That was the airplane I was supposed to fly last year, the Taurus Electro.

This year’s announcement, if it goes off as planned, will be the Alpha Electro, which was just going into the conceptual testing phase when I was in Slovenia last year. The Alpha is basically a variant of the Pipistrel Virus, a light, all-composite, highly efficient two-place airplane that sells in the U.S. as a light sport and as a microlight in Europe. Its light airframe makes it an ideal choice for an electric and what Pipistrel envisions is a straight-up electric version of the Rotax-powered airplane: same airframe, generally the same performance, but less payload and, obviously, less maximum endurance.

Siemans AG, the giant German electronics and electrical firm, pitched in to develop the motor, which is a 31-pound unit a little bigger than a ceiling fan motor and about the same shape. The prototype’s motor is capable of 85 kw or about 114 hp, but Pipistrel’s Tine Tomazic told me the production version will have the same output as the gasoline airplane—about 80 hp or 60 kw. The light little Alpha does well with that power, hardly lacking for climb rate.

But how much battery weight does this puppy have to haul around? A lot. Where the gas version tankers 78 pounds (35.5 kg) of fuel, the Electro needs 277 pounds of LiPo cells or 126 kg. Saving it is what electric propulsion taketh away in battery weight, it giveth back in far lower engine weight. So all in, the Alpha Electro will have an empty weight around 377 kg or 829 pounds compared to 631 pounds (287 kg) for the gasoline model I flew last year.

The electric version will have a useful load of 380 pounds. That’s 190 pounds each for student and instructor except in those cases where both the CFI and student are people of girth, in which case I suspect it will be flown overgross, just as Cessna 152s are now. (I know this a shock, but then so was finding out about Santa Claus and the Tooth Fairy.)

By comparison, a typical Cessna 152 has a useful load of about 480 pounds (218 kg). Down fueled with half tanks, it’s good for 402 pounds of payload or a little less. With full fuel, a 152 can carry about 350 to 370 pounds. The 152 can, of course, be down fueled to balance the weight; the electric airplane can’t, at least while retaining useful endurance. Speaking of which, how much of that will the Alpha Electro have? Pipistrel says its testing is on target for about an hour, with 30 minutes of reserve, including a cabin heat budget. Is that even useful?

Based on discussions with its customers, Pipistrel is marketing the airplane as an “airport” trainer, the ship that stays in the pattern to do touch and goes and landing training. I’ll get to the economics of that in a moment. They don’t see it as cross-country trainer, for obvious reasons, and maybe not even a maneuvers trainer. So to work, the Electro has to be placed in a school whose business model supports an airplane dedicated to one purpose. In the U.S., that would be a tough sell; in Europe, apparently not. In any case, if the Electro finds buyers—and Pipistrel says advance orders on it exceed any other model they’ve introduced—I predict it won’t be limited to the pattern. Schools will find a way to build it into their regular training doctrine, just as early adopters of VisiCalc used it for store inventory. I think I can get out to the practice area, conduct a 45-minute lesson, and get back to the airport with safe reserves. Only operational experience will reveal if this is practical and safe. I’m looking forward to learning how schools actually use the airplane.

The batteries are in two modules, each with three enclosures about the size of an overnight bag and weighing 46 pounds each or 21 kg. They’re meant to be quick change, so you can rapidly unplug them, slide them out on rails, and stick in fresh charged batteries. There are three battery enclosures in the front of the airplane behind the motor and three more in the back. They aren’t cheap, either. A full set of batteries costs about $11,500 with an estimated life of 2000 hours, same as the TBO on a Rotax engine.

Pipistrel is modeling flight school ops using two electric airplanes with one set of spare batteries between them, another thing it says customers are interested in. Those that want a single airplane might choose to charge between flights, which will require just under an hour. Flight schools I’ve interviewed tell me if they put 100 hours on a trainer a month, they’re viable and based on a six-day week, the Electro could just about do that, if it has good dispatch reliability. And if it’s designed right, why shouldn’t it? Pipistrel also envisions pairing the electric with a gasoline Alpha to do cross-country and other training tasks. Having flown the Alpha, I think it’s different enough that I wouldn’t want to bounce a student from an Alpha to something else.

What about the numbers? Electrics hover on the horizon as bright neon signs that say “game changer.” The definition of that overused phrase is technology that’s disruptive or completely resets the accepted paradigms. I can’t make the calculations do that, although I can support a less catchy, pedestrian phrase: does actually reduce operating costs.

Here’s the rundown, apples to apples with the two Alphas. The chart below tabulates it. The gasoline version sells for about $83,000, although check back tomorrow and that might be less, given the free fall in the Euro against the dollar. The Electro doesn’t have a precise price yet, but Pipistrel says under €100,000, so I used $100,000 for my calculations.

Add up the gasoline Alpha cost and divide by 100 hours a month and it comes to about $48 an hour composite operating costs. On the electric side, most of the costs are similar, but with obvious exceptions. Pipistrel is planning on a 2000-hour life for the major components, which are essentially the batteries. The electric motor has a 10,000/50-year projected life limited by the insulation on its windings. At 2000 hours, it needs a $400 bearing rebuild. The batteries are projected to have a 1500-cycle-to-full-charge life, which Pipistrel is also calculating as about 2000 operational hours. At the current favorable exchange rates, the battery pack replacement cost is $11,500 or about $5.75 an hour. Tomazic told me Pipistrel is considering all the costs across the board as the same as the gasoline version, except for fuel, so for my calculation, I added a fudge factor to the battery cost. Call it a budget for the unknown. There are inevitable unforeseens in a new type such as batteries that don’t last as long as projected or other unpredictable factors.

So where’s the savings? In fuel, or lack thereof. In the U.S., the Rotax will cost about $22 an hour in fuel; in Europe, make it $36 per hour, if not a little more. At typical Kwh costs in the U.S.—about 12 cents—a battery charge will cost under $2. At the highest prices in the EuroZone, $6 is more like it. Either way, if Pipistrel’s numbers are close to the mark, the hourly operational costs are about half what they are for the gasoline version.

So why’s that not a game changer yet? The airplane will be used for only a portion of the training, that part which remains in the pattern. Let’s say that’s about 35 percent of the typical 70 hours required for a private certificate—25 hours. For U.S. context, multiply that times a $22 savings and it comes to $526. OK, so maybe the pattern work is 40 percent of the hours, in which case the savings comes to $590. In the U.S., a private costs between $10,000 and $12,000 all in, so we’re talking about a 4 to 6 percent savings. Hey, I’ll take it. It’s better than an increase of that much. But a game changer it is not, at least in the U.S. At European gas prices, the electric looks much better because fuel is so much more expensive and thus a larger percentage of operating costs. Plus, in Europe, where airport noise is far more restrictive than in the U.S., they’ll like a quiet electric.

I suspect there’s a sliver of a private owner market that will buy an electric airplane for the novelty, for the greenness and tech-edge of it. I typically fly the Cub for less than an hour at a time, so it would fit my profile. I pine for the thrill of advancing an electric throttle to the sound of nothing but prop tips slicing air. But I wouldn’t spend $100,000 on an airplane to do that that has limited range. So I have no idea how robust such a market might be. Pipistrel’s healthy order book for the Electro indicates to me that there are enough schools intrigued by this technology to give it a go. They’re not all in Europe, either, Tomazic told me. Nor are they in the U.S.

Although I’ve applied U.S. economics to this analysis for the sake of context, the Alpha Electro won’t be a player in the U.S. as an LSA because the FAA hasn’t gotten around to defining light sports as capable of being electric airplanes. That’s part of the reason, I presume, that the U.S.-based Electric Aircraft Corp. is certifying its proposed Sun Flyer under the primary category. Once again, I’m afraid, the rest of the world may lead while the U.S. lags.

So where does this get us? As I’ve said before, the electric airplane evolution is not going to fizzle. Just as electric cars have made market inroads—with the trends accelerating, I might add—so will electric airplanes. Battery technology is forecast to decrease incrementally in price and increase incrementally in capacity, both curves that are going in the right direction. Unfortunately, we can’t say the same about the long-term cost of fossil fuels or the prices of the airplanes we’re building to burn them.

So at the expense of limited practicality, these early electrics show potential to at least lope the price spikes off the cost of training. To be the real game changers some think they are, I think they’ll need better endurance. I don’t know what that number is, but I’m not convinced it’s an hour with 30 minutes of reserve. To compete with gasoline, I’d want better range than that, maybe even in the training realm.

Right now, Pipistrel is plying the early-adopter market and it will be fascinating to see how schools, instructors and customers take to these airplanes. What we’ve found with LSAs is that in some schools, they are much preferred over conventional aircraft. One school I spoke with was flying the wings off its Skycatcher. But in other venues, older 152s and 172s are preferred; the LSAs molder and are often disposed of. Electric airplanes may show a similar pattern for the short term. I wonder if the novelty of flying a near-silent airplane will have such appeal as to overcome other shortcomings, some we may not even know about until electrics hit the field.

We will see soon enough. But so far, I like the direction it’s going. Now please, someone let me fly one of these things.

Join the conservation.
Read others’ comments andpost your own.