User Manual
X45
Version 1.0/2019
Copyright © 2019 by Xicoy Electrònica S.L. All rights reserved
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LINEAR
: Mean that the thrust develop linearly with the throttle setting. Could cause difficult taxi, as it would be
difficult to fine adjust the power at low settings.
HALF EXPO
: An intermediate setting between the other two modes
Stick Position
MODE
0% (Idle)
25%
50%
75%
100%
FULL EXPO
Idle thrust
6%
25%
56%
100%
% of total thrust
HALF EXPO
Idle thrust
16%
38%
66%
100%
LINEAR
Idle thrust
25%
50%
75%
100%
Throttle curves can be changed while the engine is running, so you can leave the throttle at a given position and
switch between the curves to see the difference.
Acceleration and deceleration settings.
In the “RUN” menu it is possible to change the acceleration and deceleration times. The engine is supplied and tested
from factory ready to use and usually these settings should be correct for normal use. However the user can modify
these default settings to allow the engine to run optimally in different conditions.
Leave the acceleration and deceleration in “fast” mode when using the engine with kerosene and at ambient
temperatures below 25ºC and elevation below 500m.
If diesel fuel is used, or ambient temperature is over 25ºC or altitude is over 500m, then the engine could experiment
difficulties in accelerating. Always best to test carefully when on the ground, to see the engine behaviour. Listen for
any sign of the engine in difficulty during throttle up or down. In these cases, try to set the acceleration to “normal”,
“slow” or “very slow” to find a setting where the engine operate normally.
It is much better to have an engine respond slower to throttle changes than one that just stop when asked to
accelerate faster than possible in difficult ambient conditions!
Exhaust tubes
The size and placement of the exhaust tube is not an exact science. The optimum tube diameter and the gap between
the engine exhaust and the tube intake is largely dependent of the airframe. A slow airframe with big intakes will
benefit from larger exhaust diameter and larger gap to get the maximum static thrust possible. A fast airframe, with
small intakes, bypass installation, will benefit of smaller exhaust diameter and smaller gap to get the maximum efflux
speed.
As a general guideline, use an exhaust tube of a diameter equal or larger than 45mm (1.8”) diameter, with a gap
between the engine exhaust and beginning of exhaust tube (excluding the bell mouth) of 25mm (1”).
Later you can experiment moving the engine 5mm (0.2”) forward or aft to see if performance is better. Too larger gap
will cause hot gases to recirculate to the engine intake, decreasing performance and worsening the acceleration. Too
