Electric Aircraft
Smartflyer and H55 Advance SFX1 Hybrid-Electric Aircraft Development
Smartflyer receives certified Adagio battery modules from H55, advancing the SFX1 hybrid-electric aircraft toward 2026 testing and flight phases.
This article is based on an official press release from H55 and Smartflyer.
Swiss electric aviation companies Smartflyer and H55 have announced a significant milestone in the development of the SFX1 hybrid-electric aircraft. According to a joint press release, Smartflyer has officially received the first batch of Adagio battery modules from H55, marking a critical step forward for the SFX1 Proof of Concept Demonstrator program.
The delivery enables Smartflyer to transition from component-level validation to full system integration and testing. For H55, the handover represents the continued integration of its certification-ready battery systems into active aircraft development programs, reinforcing its position in the electric propulsion market.
The SFX1 program is now entering an advanced stage of development. With the battery modules in hand, integration activities are intensifying across multiple workstreams, keeping the aircraft on track for its upcoming testing phases.
The SFX1 Program Advances
System Integration and Testing
The newly delivered Adagio battery modules will be integrated into the SFX1 aircraft as part of the next phase of development. According to the press release, this phase includes comprehensive system-level validation covering the propulsion architecture, energy management, and other critical aircraft systems.
Ground testing of the SFX1 is planned for the summer of 2026, with the first flight targeted for autumn of the same year.
“Receiving the first Adagio battery modules from H55 is a major milestone for Smartflyer and a key enabler for the next phase of our development program,” said Rolf Stuber, CEO of Smartflyer, in the company’s press release. “It also highlights the strength of our collaboration with a partner whose technology is not only innovative but ready for real-world application.”
About the Smartflyer SFX1
Industry estimates and company specifications indicate that the Smartflyer SFX1 is a four-seat hybrid-electric aircraft designed for sustainable pilot training and touring. The aircraft features a unique design with a tail-mounted propeller, which allows for laminar airflow and increases efficiency by up to 30 percent compared to conventional configurations. The hybrid system aims to reduce carbon dioxide emissions by 50 percent and noise by 60 percent, while offering a range of up to 750 kilometers (400 nautical miles).
H55’s Adagio Battery System
Certification and Commercial Deployment
The delivery of the Adagio modules reflects the maturity of H55’s product portfolio. The press release notes that the Adagio battery system has successfully completed all regulator-required certification tests, demonstrating its safety, reliability, and suitability for integration across various electric and hybrid-electric aircraft applications.
“This delivery marks an important step in bringing H55’s certified battery and propulsion solutions into operational aircraft programs,” said Rob Solomon, Chief Executive Officer of H55. “Our collaboration with Smartflyer illustrates how our technology, spanning both electric and hybrid-electric configurations, is moving from development into commercial application.”
AirPro News analysis
We note that the partnership between Smartflyer and H55 highlights the growing momentum in the Swiss electric aviation sector. H55, founded in 2017 by the technological legacy team behind the Solar Impulse program, has been steadily expanding its footprint. The company’s certification-grade energy storage systems are not only powering the SFX1 but are also slated for use in other notable projects, including the Bristell B23 Energic and a Pratt & Whitney Canada regional hybrid-electric flight demonstrator.
By securing regulatory approval for its battery modules, H55 is addressing one of the most significant bottlenecks in electric aviation, certification. For Smartflyer, leveraging a pre-certified battery system significantly reduces development risk and accelerates the path to market for the SFX1. If the summer 2026 ground tests and autumn 2026 first flight proceed as planned, we expect the SFX1 could become a strong contender in the emerging market for sustainable flight training and regional touring aircraft.
Frequently Asked Questions (FAQ)
What is the Smartflyer SFX1?
The Smartflyer SFX1 is a hybrid-electric aircraft currently in development in Switzerland. It is designed to be a four-seat aircraft suitable for sustainable pilot training and touring, featuring a distinctive tail-mounted propeller.
Who is providing the batteries for the SFX1?
H55, a Swiss-based company specializing in certified electric propulsion and energy storage systems, is providing its Adagio battery modules for the SFX1.
When will the Smartflyer SFX1 fly?
According to the official press release, ground testing is scheduled for the summer of 2026, with the first flight targeted for the autumn of 2026.
Sources
Photo Credit: H55