I have seen the future, and it works… sort of. The SureFly looks a little like an upside-down octopus, but this hybrid gas-electric octocopter is striking nonetheless. It also represents one of the most interesting ideas in light aviation right now, with a unique mix of big ideas and pragmatic engineering.
Somewhat surprisingly, this vision of the future is sitting in a warehouse in Loveland, Ohio, not Silicon Valley. While many of the biggest names in technology, from Google to Uber, work on radical concepts for VTOL (vertical takeoff and landing) aircraft, SureFly’s small team of engineers and pilots plugs away on their own concept in relative obscurity. They may even be farther along than some of their more famous competitors.
Workhorse, the company behind SureFly, has been a pioneer in developing electric trucks for commercial use, including a $50,000 pickup you can order today. One of its most important projects is a next generation UPS delivery truck that includes a roof-mounted drone for “last mile” delivery. Work on this drone got the company interested in VTOL aircraft and electric motors.
A hybrid design
The result is something much bigger than a drone – a total rethink of the helicopter, based on electric motors and computers instead of mechanical controls. While a modern helicopter is an amazing invention (I know, I fly one), it is very much a manual machine. Even in highly automated turbine helicopters, the pilot is still controlling the pitch of the blades, the speed of the engine, the pitch of the tail rotor, and a whole lot more. Unlike a drone, which will hover quite nicely with the pilot’s hands off the controls, an inattentive helicopter pilot can quickly crash because the machine is inherently unstable.
Many of these assumptions change with SureFly, mainly because electric motors deliver impressive torque and can change speed almost instantly. So instead of a centrally-mounted engine connected via lengthy driveshafts to a main rotor and a tail rotor, the SureFly has eight electric motors, stacked in pairs on four carbon fiber arms. Each motor sits right next to a fixed pitch propeller – four pointing up and four pointing down.
Like a DJI Phantom on steroids, the flight path is controlled by changing the speed of the eight motors, sometimes hundreds of times per minute. This requires serious computing power and sophisticated software, but it eliminates fully articulated rotor systems, tail rotors, gearboxes, and complicated mechanical controls. It also allows for that hands-off hover, which is perhaps the holy grail of electric, multi-rotor aircraft.
Electric motors bring other benefits, too, including a reduction in noise. While some boosters overstate this effect, the engineers at Workhorse believe the SureFly will be significantly quieter than a traditional helicopter (and early testing backs this up). That’s a critical feature for making intra-city transportation dreams come true, where the complaints of neighbors may matter more than the FAA rules.
Electric motors can also be stopped almost instantly. This makes it much faster and easier to load and unload the helicopter after landing. Instead of waiting for the blades to stop turning, passengers can jump out of the SureFly just seconds after touching down; the pilot can then start right up and take off. That should make multi-leg air taxi routes or package delivery scenarios much more efficient.
Flying the aircraft will be an exercise in systems monitoring, not old school stick and rudder. The cockpit has no collective lever and no traditional cyclic, just a single control stick in the center. Point the stick forward and the computer asks the rear motors to spin faster than the forward motors, tilting the helicopter forward. It’s the same basic idea of a helicopter’s rotor disk, but with no swashplates or pitch links.
The panel consists of a single screen that includes all flight and engine instruments, so it does feel almost like a video game. John Graber, an experienced military and airline pilot who has flown many hours in the simulator and is the lead test pilot, says he believes a pilot can learn to fly the helicopter in just a few hours.
When the SureFly is done working for the day, its four arms will fold for compact storage. The goal is to fit in garages and barns, but also trailers. That means it can be transported to the most convenient base of operations. With a 70 mph top speed and one hour of endurance, this is hardly a cross-country cruiser. Almost the entire aircraft is made of carbon fiber so it’s light: 1100 lbs. empty and around 1500 lbs. at max takeoff weight.
A lot of this sounds ambitious, and it certainly is. But a look beyond the headlines shows some thoughtful and realistic decisions – especially when compared to higher profile ventures.
Consider the two trends that are driving most of the futuristic designs right now: all-electric power systems and autonomous flight. Workhorse believes in both of these trends, but only in the medium to long term; over the next five years, neither of these dreams will be realized for passenger flights. This insight (or perhaps admission of reality) is one of the most refreshing things about the SureFly team.
Start with batteries. While some companies, notably Boeing, are betting on transformative changes in battery technology to enable all-electric aircraft, Workhorse founder and CEO Steve Burns isn’t buying it. Sure, battery prices are coming down quickly, but that’s not the issue. The energy density of batteries will have to improve dramatically in order to make all-electric aircraft a reality. Those advances are possible, but almost all are still in the lab, years from commercial availability. For that reason, SureFly is using electric motors but two gasoline generators to drive those motors. Workhorse has essentially separated the issues of electric propulsion and electric power sources.
Whereas the company’s trucks run on electric as primary and then switch to a backup generator to extend range, the SureFly flips this around, with a large battery mostly there to even out power spikes and provide quick power boosts when needed. It’s also backup, providing five minutes of power to allow a safe landing in case of engine failure.
Other safety features include a ballistic parachute, which is only possible because of the four-arm design. This can be used above 350 feet; below that the SureFly can continue flying with the loss of one of its eight motors, although only to a forced landing site. There is plenty of redundancy here, but the overall goal is simplicity. You won’t find any tilt rotors or ducted fans here like you will on the new Airbus VTOL machine.
The realistic approach to batteries is matched by a conservative plan for autonomy. While two passengers instead of one pilot and one passenger makes the economics a lot better, that is pretty far out on the SureFly roadmap. The computer on board is flying the aircraft, and this could certainly be controlled remotely instead of from the left seat. For now, though, that would present additional technical and, more importantly, certification challenges. The FAA is struggling to figure out a standard for electric motors; Part 135 charter with no pilot seems almost laughable compared to that.
Is it certifiable?
That concern about certification is ever-present: even if the SureFly design is sound, that hardly guarantees it will be certified. Will the FAA play ball? So far signs are encouraging. Everyone I talked to at Workhorse had praise for the FAA staff they have worked with, and this went beyond mere politeness.
Recent changes have combined to make this a fortuitous time to certify a radical new aircraft. Most notably, the multi-year effort to update Part 23 certification standards is finally taking hold. Phrases like “equivalent level of safety” are being used much more often, while rigid interpretations of old policy letters seem to be fading. The impact has been on FAA culture more than just rules and regulations.
The FAA also feels a certain sense of failure at stumbling out of the starting blocks with the drone boom (many other countries have zoomed past the US in terms of drone development). This time, they want to get it right. A small but telling example is whether there are eight “engines” and eight “propellers” on the SureFly, with each one requiring its own logbook, or a single drivetrain, so one logbook will suffice. So far, the FAA has decided on the latter. That’s progress.
Of course it’s not all smooth sailing when you’re certifying a new aircraft. The cockpit features two throwback instruments: a magnetic compass and a standalone altimeter. Both were required in order to earn a special airworthiness certificate (experimental), which the SureFly received last month. Other such “box-checking” requirements are sure to pop up.
Training will also require some open-mindedness from both the FAA and the insurance industry. If this is a helicopter, does it require 50 hours of training, like a Robinson R22? The helicopter Airman Certification Standards don’t seem to fit the SureFly very well either, so how will a checkride be conducted? It’s fair to say nobody knows the answers to these questions yet.
Certification is one hurdle; financial success is another, as countless aviation companies have learned over the past 50 years. As an industry maxim goes, “the type certificate is not the finish line, it’s the starting line.” Workhorse owns an auto manufacturing plant in Indiana, where it makes its own trucks from the chassis up, so this company is not naive about the challenges of manufacturing. That should give them a leg up on startups that only know engineering and venture capital. Workhorse also has over 400 dealers in place for their trucks right now, many of whom might someday offer a helicopter as well.
But finding customers for a new and unique looking product is never easy. While the popular press has written sexy headlines about “a new generation of flying cars” or “the ultimate millionaire’s toy,” neither of those hold much promise in the short term. Uber certainly has big ideas about moving millions of people around by air – indeed, this is what has caused so many VTOL startups to be founded over the last year – but other applications are much more realistic.
For Workhorse, commercial users are the focus, including local delivery companies, law enforcement agencies, agriculture, military, and yes, some passenger transport. Many of these buyers are not aviation companies in any traditional sense of the word, so the compact storage and simple flying traits will be major selling points. As CEO Burns says, their goal is not to take some share of the 900 airframes/year helicopter market, but to convince companies who would never consider a helicopter to buy a SureFly.
The competition will be stiff, with famous names like Airbus and Bell Helicopter actively testing competing ideas. Burns hopes to beat them on both speed to market and price, since many other programs are focused farther out in the future, with moonshot designs and business models.
How much for this revolutionary new machine? The Workhorse website, which is accepting $1000 deposits, advertises a “Target price under $200,000.” That certainly leaves a lot of room to wiggle, and it wouldn’t shock longtime pilots if the price approached the R22’s $300,000 level. Even still, the SureFly would still represent a significant advance in both operating cost and ease of use.
First flight took place this month, and production is scheduled to start in 2019. Like any new aircraft program, that date, along with the price, should be considered goals and not guarantees. Reaching the finish line will require patience, luck, and (perhaps more than anything) money. To keep the funding flowing and to focus on the distinct business units, Workhorse plans to spin off SureFly as its own company this summer, traded on the NASDAQ.
Whether SureFly makes it or not, the technology it’s using will remain, not least for future general aviation airplanes. Electric motors and computer control really do change things, especially if the entire aircraft is designed around these ideas. Indeed, Graber sees some parallels with the early days of Cirrus Aircraft, a comparison that isn’t quite as ridiculous as it sounds if you know your history. A small engineering team in a midwestern city trying to use composite construction and ballistic parachutes to shake up a staid industry – can lightning strike twice?