Adenau, Germany – 27.10. 2026: Helix, the UK manufacturer of the world’s most power-dense electric motors and inverters, has met with RED Aircraft at the AIRTEC Show in Augsburg to present a series hybrid generator solution for aviation: the RED A03 Series Hybrid Generator. AIRTEC is a leading international B2B trade show for the aerospace industry, future air mobility, New Space, and advanced defense technology.
The RED A03 Series Hybrid Generator brings together the RED A03 V12 diesel engine, one of the lightest and most efficient piston engines in aviation history, with a specially configured variant of Helix’s SPX177 motor: the SPX177-137D.
The SPX177-137D is a 2×3-phase synchronous permanent magnet radial flux motor, designed specifically for use-cases where weight and space are at a premium. Massing just 21.7 kg, the SPX177-137D outputs 420 kW of peak power and 32 7kW of continuous power. This means it achieves a peak power density of 19.4 kW/kg, and a continuous power density of 15.1kW/kg. This is all achieved in a volume of only 7.5 litres: 192 mm in diameter and 258 mm in length.
By pairing the SPX177-137D with a 1:5.4 planetary transmission and a RED A03 engine, the RED A03 Series Hybrid Generator can offer aviation a pre-integrated electrical generation capability without precedent. With a dry mass of just 350kg, the generator can output 380kW peak electrical power for 5 minutes and 327kW continuous power – something that typically requires a 2-tonne unit for marine and industrial applications.
As a dedicated series hybrid generator, the new unit’s electrical power density is three times greater than existing auxiliary power units. It also achieves major efficiencies in fuel economy – with a fuel burn rate of 77 kg/h, at an energy efficiency of 218 g/kWh BSFC in the optimum. Compared to equivalent turbine engines, this means 50 % fuel savings and 50 % less CO² emissions.
The maximum noise of the RED A03’s V12 is only 75 decibels at 50 meters, significantly lower than comparable aviation generation solutions. This makes it an ideal generator for eVTOLs and Air Taxis landing and taking off in city centers, and for commercial aircraft that must comply with on-the-ground noise limits at airports.
Special thanks to company SARLA Aviation in India counting on RED Aircraft – HELIX Range Extenders for eVTOL SHUNYA providing their Key Visual for the common booth!
About RED Aircraft GmbH: RED Aircraft GmbH is a German manufacturer of advanced Jet‑A piston engines, including the RED A03 V12, engineered for high efficiency, low emissions, and hybrid‑electric compatibility.