AINsight: Green Skies Ahead

 - June 21, 2019, 5:21 AM
Eviation's Alice
Electrically-powered aircraft like Eviation's Alice, on display this week at the Paris Air Show, could help pave the way to a cleaner, more environmentally conscious future for the aviation industry.

Business aviation does not rank high among the identifiable sources of greenhouse gas emitters. The General Aviation Manufacturers Association (GAMA) estimates that business aviation is responsible for about 2 percent of civil aviation’s CO2 emissions, which are themselves just 2 percent of worldwide human-induced emissions. Doing the math, that implies that business aviation is responsible for .04 percent of the global total, which is just a drop in the bucket. 

Newer, more fuel-efficient engines, lighter-weight airframe materials like carbon fibers, electronic cockpits, fly-by-wire flight controls, more direct flight routings, and procedures, and the wider use of various types of biofuels all bring the promise of greener and greener skies ahead. On today’s and the near-term horizon, experimentation with various types of hybrid and electric propulsion systems is advancing at a remarkable pace, and is soon to evolve into real-world capability demonstrations, initially without payload but soon enough carrying hot pizzas and aircraft closing documents in the same time-sensitive payloads. The real tests, of both the safety and practicality of a new world of intraurban air travel, remain shimmering lights primarily confined to the eyes of their creators, at least for the time being.

Beyond the spectacular aerial displays and commercial/military gadgetry, the 2019 version of the Paris Air Show, like all major aviation exhibitions for the foreseeable future, is a forum for the advancement of the art and science of electrically powered aviation. The challenges to getting to what could be very green skies ahead are absolutely daunting, but the rewards are so clear and compelling that this will almost certainly be our future. Clearly, much depends on designing and developing lightweight aerial vehicles, the pods in which those pizzas, contracts, and soft-squishy humans will one day ride.

  • Should the propellers push or pull, be fixed or rotate? 
  • Should there be 4 or 8 or 16 or even more? 
  • Where should the energy be stored? 
  • How lightweight can the batteries be, and how quickly can they be recharged?
  • Should the vehicle be autonomous or piloted?
  • Where can “vertiports” be developed? 
  • What services do these facilities offer, and who is going to finance and manage them? 
  • What kind of daily, monthly, or annual utilization should these aerial vehicles be designed for? 
  • Who is going to fly and manage these vehicles?
  • Do they rest outside overnight or not? 
  • If not, how will these vehicles be secured? 
  • How many will be needed by a typical operator, what is their expected design life, and where are the revenue streams to justify the capital investments that OEMs will be required to make?
  • Will these aerial vehicles be built by today’s incumbent OEMs or by a new breed of competitors to take advantage of ultra-low-cost manufacturing and materials technologies to change the aircraft manufacturing paradigm?

Not to be forgotten are those that oversee and enable the environment in which all of this takes place: the world of the policymakers, regulators, and far-seeing entrepreneurs who have a vested interest in ensuring safety and compliance, whether in air and ground infrastructure, air traffic control and management, communications networks, data sharing, machine learning, and information technology systems.

These are all fascinating questions that require deep consideration, experimentation, capital, and certainly not just a few leaps of faith. Such is the proud heritage of aviation and aerospace technology, and I am certain it is also the future. Fifty years ago, the first flights of the Aérospatiale/BAC Concorde—one from Toulouse, France on March 2 and another from Filton, UK on 9 April—led to both aircraft appearing in June at the 1969 Paris Air Show. Just weeks before the Apollo 11 astronauts first walked on the Moon, this was an unprecedented period of technological bravado and achievement, the likes of which have arguably yet been matched, despite the advent of supercomputers, digital design software, and cloud computing to replace the trusty slide rule. In 1969, the Concorde and Apollo were ultimate expressions of what many people want their aerospace vehicles to do: fly very fast and very far, even if that means with a limited human payload.  As Rosie the Riveter knew all those years ago, isn’t it better to demonstrate that “we can do it!” with real machinery, tangible hardware, and stuff that flies? Most would say “Of course!”

Following in the footsteps of jet and rocket propulsion technologies originally developed for military applications in the 1930s and 1940s, civil airliners transitioned from highly efficient piston engines to the first generation of turbojets, sacrificing fuel burn for speed. In the 1960s, fascination with supersonic flight led to a transatlantic race between the French and British against the Americans to see who would be aviation history’s pioneer. Fuel burn was a vital calculation needed to size the vehicles and their storage tanks, while ensuring the success of the mission, with little apparent focus on the potentially damaging effects of greenhouse gases and CO2 emissions on the environment.

As a whole, business aviation has been making slow, steady progress in mitigating its environmental impact, something that is likely to become a front-and-center issue in the years—and airshows—to come. Despite being a demonstrably small emitter today, commercial and business aviation are growth industries. Accelerating this growth, whether through advances in aerodynamics, aerial vehicle design, non-emitting propulsion systems, and onboard energy storage, is a stakeholder imperative. 

Forums like the biennial Paris Air Show are vital touchpoints for an industry where words, smiles, handshakes, and letters of intent are ultimately aligned to demonstrate tangible, valuable hardware. In the skies above Le Bourget, the Patrouille de France’s aerobatic display filled the June skies over Paris with the famous bleu, blanc, rouge contrails for which the precision aerobatic team is famous. “Green” smoke, an aviation oxymoron if ever there was one, may one day be part of the PAF’s aerial display, but I for one will have to think long and hard about holding my breath. In the meantime, where did I put my earplugs and long-lensed digital camera?