Hybrid Propulsion Systems

We believe that the future of aircraft propulsion systems will be electric. We also believe it is now prudent to exploit the benefits of today’s power-dense electric motors by integrating them with combustion engines to enable safer, more efficient propulsion with lower emissions. This is achieved through hybridization.

Battery Technology

Projected (400 W h/kg) specific energy still 10x lower than combustion power!


Electric motor power density now rivals small gas turbine engines.

Coupling electric motors with conventional combustion engines enables configurations with:
  • enhanced safety through redundancy
  • lower noise and emissions
  • higher performance

Emissions regulations, the high cost of fuel, efficiency concerns, and (most importantly) the low energy density of batteries necessitate hybrid propulsion systems.

The coming revolution in electric flight will allow us to achieve our carbon reduction targets with quieter and more environmentally friendly transport for the next century.

Looking to 2030 – when the International Air Transport Association (IATA) predicts one billion more people on the planet, and six billion annual fliers – the case for championing the hybrid-electric transition is strong.

Notional Parallel Hybrid Architecture

Proprietary engine modification enabling use of Unleaded gasoline & Sustainable Ethanol & Biodiesel blends

Demonstrator: Parallel Hybrid Propulsion

Demonstrator: Overall Objectives

Phase 1: Technology Demonstrator
  • Retrofit Certified Aircraft w/ Hybrid-Electric Propulsion System
  • Prove Concept
  • Attract Market Attention
  • Initiate FAA Supplemental Type Certificate (STC) Process
Phase 2: Kickoff Production/Sales Program
  • Sell Retrofit Kits
  • Sell Service

Phase 3: Development & Demonstration with Gas Turbine Engine

Sample Mission Profile (San Diego / LA)

All-Electric Takeoff & Climb to 10,000 ft
  • 250 kW
  • 2,000 ft/min Rate of Climb
  • 5 minutes
Cruise with Engine only
  • 20 minutes
  • Restore to 75% charge (~15 kWh, charge rate: 45 kW)
  • 500 ft/min
  • 10 minutes
  • Restore to 100% charge (~5 kWh, charge rate: 30 kW)
  • Descend as required – 5 minutes
Land & Repeat
Electric Taxi Out
All-Electric Takeoff & Climb to 10,000 ft
  • 250 kW
  • 5 minutes
  • 2,000 ft/min Rate of Climb
Cruise with Engine only
  • 200 kW
  • 20 minutes
  • 100 kW
  • 10 minutes
  • Descend as required
  • 5 minutes
Electric Taxi Back


Up to 10 minutes of Emergency TO power (comparable to OEI for a twin-engine)

Performance Boost
  • Up to 2x Rate-Of-Climb
  • Superlative High-Density Altitude Takeoff Performance

Quiet & Clean Operation in Vicinity of Airport

2 gallon Fuel Savings (22% of a total 1-hr mission)

400 hr Engine TBO Extension


  • ~1/3 Useful Payload (~350 lbm)
  • ~$50,000 (targeted consumer cost)