Performance Data And Fuel Consumption; Explanation Of The Parameters - Rotax 915 i A SERIES Operator's Manual

5.1) Performance data and fuel consumption

Ambient
Conditions
Engine Conditions
Critical Altitude

5.2) Explanation of the parameters

Parameters
Case Number Sequential number
[No Unit]
rpm [RPM] Engine speed
p_ambient [bar] Pressure at ambient depending on altitude and weather conditions. The
pressure was calculated according to ISA conditions at altitude. Engine
deck was calculated with different altitudes from sea level to max operation
altitude.
T_ambient [°C] Temperature at ambient depending on altitude and weather conditions. The
temperature was calculated according to ISA conditions and additional tem-
perature variation -15 °C (5 °F), +15 °C (59 °F) and +30 °C (86 °F).
ECU_thottle_lin Linearized throttle position as given by the ECU.
[%]
Altitude [ft] Altitude correlates to the ambient pressure (p_ambient) according ISA.
power_observ- Power observed (certified) at the propeller shaft at given ambient conditions
ered [kW] and engine conditions. This value means the LOWER LIMIT of the power
tolerance range. Depending on circumstances the delivered power can be
up to 6% higher but not lower than the power stated in the engine deck.
Page 5-2
December 01 2017
Information on performance and fuel consumption are summar-
ized in the ROTAX® Performance and Fuel Consumption
Model.
The Performance and Fuel consumption model for this engine
is only available in the electronic version of this document (see
Appendix) which can be download on our website.
www.flyrotax.com/ documentation.html
Note that all informations provided are model based and there-
fore are subject to tolerances. This chapter summarizes the pa-
rameters and the constraints that need to be considered when
working with this data.
The actual power and fuel consumption is highly depending on
the installation, the compliance to predefined maintenance
events and the way the engine is operated. Those values need
to determined and provided by the aircraft manufacturer.
Ambient conditions are given by the pressure in the ambient
(p_ambient) and the temperature in the ambient (T_ambient).
Engine conditions are given by the engine speed (rpm) and
throttle position (ECU_throttle_lin).
The engine was designed for a critical altitude up to 15000 ft.
BRP-Rotax
Explantaion
Effectivity: 915 i A Series
Edition 0 / Rev. 0