In This Aerospace Market, Electric Is Really Taking Off

Bye Aerospace secures substantial orders for electric trainers.

The electrification of aviation is a difficult challenge. The high weight of batteries, and the resulting short range and limited payload that results, have limited applications of electric drive to smaller, propeller-driven general aviation aircraft.

But flight training, which typically uses smaller, short range piston powered aircraft, is ideal for electrification. Denver-based Bye Aerospace has created a purpose-built two-seat electric trainer called the eFlyer2, which is in the FAA certification process right now. Four flight training companies have ordered 340 aircraft, a production run that may nucleate the first sustained mass production of electric light aircraft in America.  

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Episode Transcript:

The electrification of ground transportation is now in full swing, with all major automakers building electric vehicles with charging infrastructure under construction everywhere. Aviation, however, is expected to lag motor transportation for some time.

The reasons are purely technical. Batteries are heavy, and unlike aviation fuels, electricity, when used, doesn’t lighten the aircraft, resulting in a landing weight that is the same as the takeoff weight. Keeping batteries small and light enough for practical use means aircraft that are small and have limited range.  

But there are advantages. Aviation fuel is very expensive, and electricity is of course not only cheap, but it’s universal. No one ever had to develop special electrons to power aircraft compared to motor vehicles. Another major advantage is maintenance costs. Even small general aviation piston engines cost tens of thousands of dollars to overhaul, and engine life is a major per-hour operating cost. Electric motors are subject to inspections but are in most ways maintenance free. The same is true of batteries. 

Electric aircraft are also quiet, which can be a consideration where operations are close to residential areas, and of course they have a minimal environmental impact.  

But what aviation market wants light aircraft with limited range, even if the operating economics and environmental impact are favorable?  

A logical market is for training. The nature of training is usually taking off and landing at the same base, with some limited cross-country flying. General aviation uses like training are more likely to take place at facilities which are near residential areas, as well, and the economics of the industry require low operating costs and high-availability rates, both of which are offered by electric aviation.  

 A new generation of airframe manufacturers are racing to fill this market, and one of them is Denver-based Bye Aerospace. That company has developed a small two-seat electric aircraft for the general aviation and training markets, the first of several battery electric aircraft, including a high-performance twin. 

The trainer, called eFlyer2, is a clean sheet design made of carbon composites which the company claims has twice the aerodynamic efficiency of a conventional piston powered single. The elimination of the need to flow air around the cylinders for cooling is a significant advantage, and combined with the highly laminar flow possible with composite construction and a small wetted area, the aircraft has relatively high performance, cruising at about 100 knots at 10,000 feet with a 1,000 ft./m rate of climb. With a 450-pound payload, economical cruise is 220 nautical miles with VFR reserves, with an absolute flight duration of  three hours at 73 knots.

The Safran electric motor is rated at 150 hp maximum, and the exact details of the lithium-ion battery have not been revealed by the company. Important for a trainer, stall speed is a modest 48 knots. The aircraft’s equipment includes Garmin avionics and a whole aircraft ballistic parachute recovery system.

The aircraft has flown and is currently in the FAA certification process under the new FAR 23 Amendment 64, which the FAA intends to allow straightforward certification of electric aircraft under the “Normal Category.” 

Bye Aerospace has a current order backlog, and the company declares it has over $1 billion in value. Significantly, Aviation Week is reporting that the company has signed letters of intent with four flight schools for a total of 340 aircraft. Bye Aerospace has declined to name the customers. 

The company is in a strong position to become a major player in the training market: their craft are well along in the certification process, it has a large order from existing operators of training aircraft and has a product whose performance characteristics are uniquely suited for the training mission. The development of more advanced aircraft, however, will require significant financing, and if eFlyer2 is a hit, major airframers that build the general aviation aircraft that we have known for decades will likely be interested. We’ll be following developments. 

Written by

James Anderton

Jim Anderton is the Director of Content for Mr. Anderton was formerly editor of Canadian Metalworking Magazine and has contributed to a wide range of print and on-line publications, including Design Engineering, Canadian Plastics, Service Station and Garage Management, Autovision, and the National Post. He also brings prior industry experience in quality and part design for a Tier One automotive supplier.