An Australian engineering company has won a major contract to supply a new engine for a pilotless military aircraft, breaking new ground to overcome some of the limitations of other engines currently used in so-called 'drones'.
[Image, right: Orbital's director of engineering, Geoff Cathcart, with an early prototype of the HFE "Redback" Small Unmanned Aerial System engine.]
Perth-based Orbital Corporation has been contracted to supply its Heavy Fuel Engine (HFE) – nicknamed internally as 'the Redback' by Orbital staff – to American unmanned aircraft systems manufacturer AAI, a Textron company.
The engine will be fitted to a Small Unmanned Aircraft System (SUAS) developed with AAI's Australian division, Aerosonde, which will see service with the US Navy and Special Operations Command.
The contract, worth up to $4.7 million throughout 2012, is the result of a two-year effort by Orbital to perfect a tiny two-stroke engine that can run reliably on military specified heavy fuels while meeting aggressive fuel economy, weight and noise reduction targets.
"Key to our engineering team's success with the Redback has been the use of Orbital's patented FlexDI fuel injection and engine management system," said Orbital's director of engineering, Geoff Cathcart.
"FlexDI differs from conventional direct injection systems because it injects the fuel at comparatively low pressure and utilises air pressure to atomise the mixture as it is delivered to the combustion chamber.
"The system provides electronic lubrication control for reliability and its greater fuel efficiency extends the flight range of the SUAS by up to 40 per cent, or allows AAI to increase the payload."
Most small unmanned aerial vehicles (UAVs) currently in service use conventional gasoline-powered two-stroke engines which are notoriously thirsty, noisy and can be unreliable.
The US military and NATO are moving to phase-out gasoline use, in part because of its relatively high volatility compared with 'heavier' JP5 and JP8 kerosene-based fuels.
Orbital's HFE Redback is a single-cylinder engine constructed of lightweight materials and will fit in a shoebox.
Engineering development to reduce its noise emissions included refinements to the engine block, exhaust system, speed of revolution and propeller design.
"This is a good example of Australian innovation and demonstrates our engineering and product development capabilities," said Orbital chief executive and managing director, Terry Stinson.
He described Orbital's success in developing and supplying the engine for the AAI Aerosonde SUAS as an important step forward for the company.
"This is an exciting new market for Orbital; it builds on our core technical strength, uses our patented FlexDI technology and moves Orbital into the engine supply business in an international market," Stinson said.
"The requirement for the small unmanned aerial systems market is growing fast and we look forward to realising this potential."
Orbital is better known for its engine development work for the automotive and recreational vehicle industries.
Its FlexDI technology has been fitted to more than 650,000 scooters, all-terrain vehicles, marine outboards and auto-rickshaws worldwide since 1996 and is considered a technical benchmark in the automotive sector.