User Manual
X45
Version 1.0/2019
Copyright © 2019 by Xicoy Electrònica S.L. All rights reserved
Page
9
Idle rpm 60,000
EGT at max thrust 550 -700´C
Fuel consumption at max thrust 140g / 4.7oz per min
Minimum exhaust tube diameter 45-50mm / 1.8-2”
Battery recommended 2S LiPo or 3S LiFe >1000mAh
Glow plug volts 6v
Restart capable, 2 modes, manual (glider) & automatic
Fuel / Oil, Kerosene or 4% oil mix. See text for breakdown
*The specifications may be subject change without notice as new updates and developments are added to the
production model.
Engine Description
The engine is a miniature turbojet design produced specifically to produce thrust to power small model aircraft. It has
a single stage billet machined centrifugal compressor and single stage cast Inconel axial flow turbine mounted on a
single shaft. The engine is fitted with a long life ceramic glow plug which enables the engine to initiate combustion
directly on liquid fuel after which further fuel is gradually introduced into the main part of the combustion chamber
to provide combustion heat to operate the engine. A high speed brushless electric starter motor fitted with a clutch
mechanism to the front provides drive to the rotor up to self-sustaining speed for starting the engine. The starting
sequence is controlled by an electronic system fitted to the engine (ECU) which initiates the start sequence and
controls the parameters of the engine within design limits.
The engine rotor shaft is supported by two ceramic bearings which are lubricated by a small percentage bleed off the
pressurized main fuel supply, which should contain a small percentage of oil for this purpose. The rotor discs are
separately balanced and then 2-stage dynamically balanced on assembly to the engine. Disturbing the rotor will lose
this delicate balance and the engine will need to be returned to a service unit for rebalancing.
The fuel for the engine is provided from a fuel tank and fed through a small pump driven by a 3-phase (brushless)
motor that has its own intelligent control. The engine speed between idle and maximum is controlled by varying the
speed of the fuel pump rotor by command from the electronic device called an ECU (Electronic Control Unit) that is
mounted under the front cover of the engine. This sends commands to the fuel pump via a connector board (Hub) to
turn at a certain rpm (and therefore flow rate) to deliver a precise amount of fuel and the fuel pump automatically
adjusts itself to this rate. The communication between the ECU and fuel pump and all other function accessories,
display, telemetry etc is via a single wire bidirectional digital data link, no analogue voltages are used and operation
is not voltage sensitive.
