Bye Aerospace Reveals Electric Airplane Suppliers

Bye Aerospace says it is nearing the first flight of the electric eFlyer 2 two-seat training airplane and has revealed suppliers that will provide major components and equipment for the program. These include composite structure, powerplant, batteries, and avionics. 

A key component is the Safran Electrical and Power EngineUs 100B1 electric motor, which is EASA-certified and undergoing the FAA validation process, according to Bye CEO Rod Zastrow. The motor will be powered by MagniX USA battery modules, redundant power distribution, and charging equipment. Sensenich Propellers is supplying the propeller.

The composite airframe will feature materials from Toray Composite Materials America, while Composite Approach is building the full-scale eFlyer 2 prototype with the empennage made by Flying S. The nose landing gear and precision-machined components are sourced from Risse Racing. Garmin will provide the touchscreen G500 TXi display and other avionics.

The eFlyer 2 airframe consists of 275 composite parts. Bye Aerospace is still in discussions with Composite Approach and Flying S about production planning. “I can’t disclose agreements quite at this point,” Zastrow said, “but we’re very pleased, and I think there’s a bright future ahead with them as partners. Composite Approach gave us some very positive feedback that, in their judgment, they believed the aircraft was well designed for manufacturing and assembly, and felt that the assembly of the composite parts went far faster and smoother than they had anticipated.”

To prepare for the first flight, the eFlyer 2 has undergone structural load testing of the wing, fuselage, and flight controls, and limit-load testing as well as low- and high-speed ground testing. The battery engine assessment truck (aka “the Beast”) is a mobile test rig carrying a forward fuselage, motor, and propeller, and is used for propulsion system testing. The Beast is also helping Bye engineers develop the pilot interface for the electric powerplant, which the company elected to develop in-house.

Bye Aerospace has been working on the eFlyer 2 program for many years and first applied for FAA certification in 2018. Plans are to meet Part 23 Amendment 64, according to Zastrow. “This aircraft will be the first one ever built under Amendment 64, which requires it to be highly resistant to spin or spin entry. At the same time, we’re also the first one to apply for electric propulsion as our means of propulsion.”

Because the initial application was so long ago, Bye Aerospace has had to update its application. While some elements of the design have changed since 2018, he added, “In terms of the methods and means of compliance, those haven’t changed. We do have our G2 issue paper, which, in everyday jargon, means we have our certification checklist in hand. We believe, based on policy, that’s an unchangeable document with regards to how we certify, so we think we know where the goal posts are in nearly all areas.”

With the new FAA Part 22 rules for light airplanes expected to take effect on July 24, Bye Aerospace is also looking at certification under the MOSAIC consensus standards. “We believe we qualify pending the results of our stall speeds,” he said. If this is the case, then Part 22 would allow the company to accelerate initial production.

However, he added, “We are so advanced in our Part 23 certification path…our system-specific certification plans, our certification checklist, our functional hazard analysis have generally all been accepted by the FAA under Part 23, so there’s a reasonable question as to whether we want to follow a path of qualifying under Part 22. We are doing everything we can to stay engaged with the FAA. We participate in the ASTM committees, helping develop the policy for the FAA adoption [of Part 22]. So it depends on what we see with the FAA release of the consensus standards as to what path we go down.”

Part 23 certification may ultimately be necessary because 50% of the eFlyer market is international, according to Zastrow, although “We also know that the FAA is talking to EASA about Part 22 or its equivalent [in Europe].

“Even if Part 22 wouldn’t lead to international deliveries,” he said, “at least initially, it can be the fastest path for us to get some training aircraft in the hands of U.S. customers, and importantly, everything we learn on that path can probably be applied to the Part 23 certification effort.”

Bye Aerospace’s order book stands at 1,124 eFlyer 2s and four-seat eFlyer 4s. About 40% of those are backed by non-refundable deposits, according to Zastrow, and the remainder are secured by letters of intent.

With the MagniX batteries, Bye Aerospace anticipates that training missions of two hours will be possible, with a 30-minute reserve. “That’s our goal,” he said. “We think the technology exists. We don’t need to create new technology.”

First deliveries could happen in 2027 if Part 22 qualification becomes possible. “It would be low-rate production, probably at a rate of 12 or less a year, at least initially,” Zastrow said.