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

50 Dossier | Danielson Aircraft Systems Trident 100 TD2 turbodiesel of injector timing, and have a lower cetane rating (the readiness to ignite a fuel in a CI engine), which lowers power output. Kerosene also attacks conventional injector pump seals, but that is straightforward to counter at the design stage. The Trident project started in 2007, and the first customer engine was the dual-stage turbo 100 TD2. That in turn was followed by development of two I4 derivatives, one with the same bore (76 mm) and stroke (80.5 mm) as the 1.1 litre for 1460 cc, the other a larger (86 mm) bore and longer (97 mm) stroke for a 2250 cc displacement. Early on in the customer engine project the 100 TD2 met its performance target; subsequent development focused on reliability, and Danielson’s extensive testing facilities include the ability to simulate the engine running at altitude. The Trident series was launched onto the open market at the 2014 AUVSI show in Orlando, Florida, where this research was conducted. Charging and fuelling The 100 DT2’s two-stage turbocharging sees the use of two individual turbochargers that are fitted in series. The charge air enters the compressor of turbo one then, having been initially compressed, travels on to the compressor of turbo two, where it is further compressed before being fed to the engine through an air-to-air aftercooler. The plenum that then feeds the three cylinders is integrated into the cylinder head. The exhaust gas is fed first into the turbine of turbo two, then to the turbine of turbo one before exiting to the atmosphere. The turbos are straightforward designs – no Spring 2015 | Unmanned Systems Technology Danielson Aircraft Technology Trident 100 DT2 UAV engine I3 76.0 x 80.5 mm = 1095.6 cc Two-stage turbo-supercharging Diesel and kerosene-based fuel options (36-70 cetane) Aluminium structure Linerless, plasma-sprayed bore coating Five main bearings, plain Steel crankshaft, three pins Steel con rods Light alloy pistons, three rings Chain-driven single overhead camshaft Two valves per cylinder Vertical valves Undisclosed valve sizes Mechanical direct injection 15:1 compression ratio Maximum rpm, 3600 Some key suppliers to this engine Main castings: in-house Bore coating: Oerlikon-Metco Bore coating: Capricorn Crankshaft: in-house Camshafts: in-house Pistons: undisclosed Con rods: in-house Valves: undisclosed Turbocharger: in-house Carbon fibre cam cover: Scaero DLC coatings: Oerlikon-Metco Anatomy: Danielson Aircraft Technology Trident 100 DT2 The Trident 100 TD2 uses two-stage turbocharging The charge air enters the compressor of turbo one then, having been initially compressed, travels on to the compressor of turbo two