Brock Technologies has flown its Spear unmanned air vehicle with a heavy fuel engine.

The powerplant, Ultra Electronics' DF-70, allows the Spear to run on heavy fuel as required by the US military. The DF-70 produces 30hp, allowing for a significantly higher top speed and payload capacity, Brock Technologies said.

The Spear has demonstrated a speed of to 62kt (114km/h), but this is likely to increase as flight testing continues.

"Each flight we are slowly expanding the Spear's flight envelope as we unleash the power of the DF-70 and work our way up to full power and full endurance," said company president Keith Brock.

Spear - Brock Technologies 

© Brock Technologies

The Spear was previously powered by an electric engine (above). The modular aircraft is built with variable-length wings, which can be changed according to mission needs.

Source: Flight International