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Insitu N20 UAV 50 cc two-stroke single
|
Dossier
Unmanned Systems Technology
| June/July 2016
and four fasteners secure the
assembly to the head.
The spark plug is M10 with a
remote coil controlled by the ECU,
as are the injector solenoids. Key
inputs to the ECU are crankshaft
position (the detail of which
sensor is undisclosed), throttle
position, atmospheric pressure and
temperature, and cylinder head
temperature. The ECU also talks to
the PSU and the craft’s control unit.
The engine mounts are formed
integrally with the crankcase in the
form of a pair of ears on each side.
Those four points allow the engine
to be attached to the airframe via
vibration-absorbing isolators.
MIL-Spec fasteners are used
throughout, as are MIL-Spec
electrical connectors, which are
EMI-shielded. The engine core
weighs 1.6 kg, and the complete
engine 2.7 kg. That includes the
exhaust, cooling duct, cover and
mounts but not off-engine items
(engine management box, ignition
coils and fuel and oil tank/pumps).
The engine is topped by a carbon
fibre cooling duct under an optional
carbon fibre top cover, the latter
being designed to form part of the
fuselage streamlining.
Some key suppliers to the N20
Main structure:
undisclosed
Bore coating:
undisclosed
Crankshaft:
undisclosed
Piston:
undisclosed
Con rod:
undisclosed
Big-end bearings:
Koyo
Main bearings:
SKF
Small-end bearings:
INA
Seals:
SKF
Fasteners:
Aircraft Spruce
Ignition:
Orbital
Spark plug:
NGK
Fuel injector:
Orbital
Engine management system:
Orbital
Throttle actuation servo:
Volz
Oil pump:
undisclosed
Oil filter:
Orbital
Generator:
Sullivan
Power supply unit:
Sullivan
Fluid lines:
Goodrich
Fluid couplings:
Battlefield
Fuel pump:
Flightworks
Dynos:
Schenck
Components of the Insitu/Orbital N20