Unmanned Systems Technology 018 | CES show report | ASV Global C-Cat 3 USV | Test centres | UUVs insight | Limbach L 275 EF | Lidar systems | Heliceo DroneBox | Composites

56 L imbach is a long-established manufacturer of two- and four-stroke aero engines. The aviation world places great emphasis on time-proven dependability and that, plus state-of-the- art performance makes these up-to- 120 kW, gasoline-fuelled German power units much coveted among developers of aircraft, be they manned or unmanned. Limbach engines are used in the likes of ultralight, very light, light, experimental and sports aircraft. We recently visited Limbach’s design, development and production facility near Bonn, where we were given an in-depth insight into the company’s technology. As such, we offer here a detailed profile of the Limbach L 275 EF. It is a small displacement two-stroke boxer twin that represents extensive refinement of its type, having been honed over almost 50 years. It is a fine example of contemporary gasoline-fuelled engine engineering, exploiting fuel injection and a full engine management system. Background Peter Limbach’s father trained as an aircraft mechanic with the Luftwaffe in the 1940s, then after the war he spent 12 years in Canada. Coming back home to Königswinter, near Bonn, he found his command of the English language to be a rare skill, which he put to good use by refurbishing Volkswagen flat-four engines and selling them to the USA. Those were for automotive use, but in the 1960s there emerged a trend to convert this boxer power plant for use Ian Bamsey details the technology behind this lightweight two-stroke boxer – a result of decades of refinement February/March 2018 | Unmanned Systems Technology Air conditioning Light and compact – Limbach’s high-performance L 275 EF