Lycoming Engines has begun overhauling the heavy-fuel powerplants in AAI’s Aerosonde Mk 4.7 unmanned air vehicles, and will make design changes intended to improve the engines’ reliability, say executives.
Both Lycoming and AAI, which supplies the small Aerosonde UAV to the US Navy on a fee-for-service basis, are units of Textron.
David Phillips, Textron’s vice-president of small and medium endurance unmanned aircraft systems, told Flightglobal the engine work was brought in-house largely because Lycoming meets processes and standards set by the US Federal Aviation Administration for manned aircraft.
The result will be a more reliable aircraft and a competitive advantage, says Phillips, who adds that the previous engine manufacturer did not meet those standards.
Phillips declines to name that company, but Australian manufacturer Orbital announced in 2012 that it landed a contract to make heavy-fuel engines for Aerosonde.
The switch to Lycoming was announced by Textron chief executive Scott Donnelly during the company’s third quarter earnings call on 18 October.
Donnelly says Textron continues “to experience unacceptable quality from our engine supplier”, adding that engine failures have led to aircraft losses, forcing the company to replace engines, airframes and navigation systems at great cost.
“The weak point of the system is this engine,” he says.
Phillips says engines in many of the company's Aerosondes are due for an overhaul; work that is now being done by Lycoming.
In addition, Lycoming will begin making improvements to the engine’s design, and will also manufacture new examples, says Phillips.
Even before the change, the Aerosonde, which is launched from a catapult-like system and retrieved with a net, met its expected mission readiness rate of 95%, says Phillips. The type's performance has been comparable to competing UAVs in the same class, he adds.