Unmanned Systems Technology 003 | UAV Solutions Talon 120 | Cable harnesses | Austro Engine AE50R and AE300 | Autonomous mining | AUVSI 2015 show report | Transponders | Space systems

44 Dossier | Austro Engine AE50R rotary and AE300 I4 The AE50R Notably, Wankel engines have been developed by Mazda for cars, and by BSA/Norton for motorcycles. Norton’s compact twin rotor was also developed as an aero engine, and when the British company ran into difficulties in the 1980s the rights to that project were acquired by a company called Mid West, also based in the UK. In 2003, the Diamond Group bought Mid West and moved it to Germany, where it owned a factory. In 2007, Diamond decided to establish Austro Engine on a greenfield site next to its base near Vienna to develop a range of aero engines. Thus the newly created Austro Engine took over the rotary project, which then embraced both single- and twin-rotor versions, while it also began developing a compression- ignition reciprocating engine. Since Austro Engine was established, customer demand has been for a single-rotor engine, the AE50R, and its core design is unchanged since Austro Engine inherited it in 2007. The engine was originally equipped with a carburettor, but since 1999 it has had port injection. The current engine control unit (ECU) is a design specified by Austro Engine, while under its guidance various manufacturing processes have been improved, to the benefit of tolerances and reliability. To date the AE50R has been used in more than 300 unmanned helicopters produced by fellow Austrian company Schiebel. These have a 3.4 m rotor and a 3.1 m fuselage, and a maximum take-off weight of 200 kg. The AE50R is also used as an optional engine in gliders made by German company Schleicher and other undisclosed applications. Austro Engine’s chief operating officer Peter Lietz emphasises that the AE50R is the only rotary aero engine available at the moment that has certification from national aviation authorities. While that isn’t currently a requirement in the UAV world, he anticipates that it will soon become one as the commercial market opens up. Key advantages of the rotary engine are its inherent compactness – especially useful for many UAV applications – and a high power-to-weight ratio. It also has a low vibration level relative to reciprocating engines, which again is well suited to UAV applications, as is its inherent simplicity. Each of the four strokes of a reciprocating engine nominally Summer 2015 | Unmanned Systems Technology Epitrochoid, sideplates and eccentric shaft: Gerhard Rauch GmbH Surface coating: Bodycote Surface coating: IPT Lubricants: Castrol, Shell Dynos: AVL CMM equipment: Zeiss Gearbox: Hör Technology GmbH Gearbox: Maschinenbau Durst GmbH Development partner: Pankl Aerospace Systems Europe GmbH Some key component suppliers to the AE50R and AE300 Drawing of the AE50R, with output on the far left and air intake for cooling the rotor on the far right Key advantages of the rotary engine are its compactness – especially useful for many UAV applications – and high power- to-weight ratio