Unmanned Systems Technology 020 | Alpha 800 I Additive Manufacturing focus I USVs insight I Pegasus GE70 I GuardBot I AUVSI Xponential 2018 show report I Solar Power focus I CUAV Expo Europe 2018 show report

22 W hile the design of the Alpha 800 helicopter is not radical, the engineering philosophy that Spanish manufacturer Alpha Unmanned Systems has applied to its creation and applies to its further development aims for radical utility, reliability and affordability. This approach has paid off, as the 14 kg, 1.7 m-long machine is working in research and surveillance missions in five countries, carrying 3 kg of payload for up to 2.5 hours, while Alpha is working on improvements to the engine and rotor systems to increase payload and endurance, and reduce noise. Chief engineer Alvaro Escarpenter says the main challenge faced by the programme has been to make every system, subsystem and component work together as an integrated product – a professional-quality industrial tool. Focusing on reliability and durability, Alpha took a simple, direct approach. “In many cases we chose the easy way – the main mechanical components are under-stressed to provide a good safety margin,” Escarpenter says. That applies to the engine, the rotor systems, servos, drive belts, pulleys, shafts and the airframe structure. Alpha has used commercial off-the-shelf components as much as possible on the UAV. Bearings, belts, pulleys and gears are industrially available components, and are proven low-cost systems that Alpha has analysed and subjected to a set of mechanical tests to ensure they will stand up to long-term use. In normal operation the single-cylinder two-stroke engine uses 35-50% of its rated power, providing a healthy margin and boosting reliability. Any maintenance that customers can carry out has been kept to a minimum, and consists of replacing consumables Peter Donaldson looks into the development of this helicopter, which puts usefulness and dependability to the fore Conventional wisdom June/July 2018 | Unmanned Systems Technology