Unmanned Systems Technology 002 | Scion SA-400 | Commercial UAV Show report | Vision sensors | Danielson Trident I Security and safety systems | MIRA MACE | Additive manufacturing | Marine UUVs

48 D anielson Aircraft Systems (DAS) is part of the Groupe Danielson organisation based beside the Magny Cours (former Grand Prix) circuit in France, and well known in the automotive world for its road engines. Danielson has enormous depth of experience of compression-ignition (CI) engines, so popular with French car manufacturers. That experience, and its increasing involvement in aerospace, led to the French military commissioning it to develop a clean-sheet-of-paper turbodiesel specifically for UAV use. Following that commission DAS now has a range of three Trident engines, of which the initial inline three-cylinder (I3) 100 TD2 customer unit is profiled here. The director of DAS, Frederic Hubschwerlen, says the Trident project was specifically targeted at the UAV market rather than general aviation. The customer Trident was developed as a complete package with all ancillaries including the cooling system and transmission through to the propeller. The state-of-the-art 100 TD2 is a 1.1 litre I3 that features two-stage turbo-supercharging yet has a dry weight of only 70 kg. It runs on regular diesel or heavy fuel and exploits mechanical rather than electronic injection to keep it free from electromagnetic interference. Among its innovations is a novel torque-smoothing system to protect the transmission. Everything for the project was designed in-house at DAS, whose extensive manufacturing capability meant that very little component production had to be outsourced. Although Groupe Danielson has extensive CI experience, it didn’t follow that the Trident engines had to be turbodiesels; they could have been spark ignition (SI) like many existing UAV engines. The design team saw a number of advantages from the use of CI. Regardless of power level – and Trident is catering for 100 to 180 bhp – the top priority in the UAV market is flight time. In this respect CI is theoretically advantageous compared with SI, since it is inherently more fuel-efficient. A higher compression ratio and a lack of throttling Ian Bamsey investigates a state-of-the-art French turbodiesel that’s been created specifically for UAV use Spring 2015 | Unmanned Systems Technology Three-pronged attack Cutaway of Danielson’s Trident, three-cylinder turbodiesel