The Orbital UAV HFDI-150 is a twin-cylinder two-stroke heavy-fuel engine featuring a horizontally-opposed design. Weighing 10.4 kg, the MIL-STD-810H qualified engine can deliver 11.9 hp with ultra-smooth low-vibration performance, and enables plug-and-play integration with a variety of UAV airframes.
The advanced propulsion system features Orbital’s FlexDI fuel injection technology, atomizing fuel to smaller droplets for a cleaner burn. FlexDI offers >30% lower cruise fuel use and high specific power, and also meets MIL-STD-1474D specifications for noise.
The robust engine has completed multiple 3x 150-hour FAR33.49b durability tests and 500-hour mission profile durability tests. It has been selected for Textron Systems’ Aerosonde MK4.8, a tactical hybrid VTOL UAS that has been purpose-built to meet the U.S. Army’s Future Vertical Lift requirements, and has been proven with 25,000 operational hours in the field.
Specifications:
| Weight: | ~10.4kg (includes ECU, mount, pumps, harness, propeller) |
| Power: | 11.9hp (8.8kW) @ 6500 RPM |
| Fuel Consumption (BSFC): | ~330 g/kWh @ typical cruise |
| Max Operating Altitude: | 20,000 ft AMSL |
| Operating Temperature: | -30 to 55 °C including start |
| TBO: | 500 hrs |






