I A P 2 0 2 1 . 0 0 1 - A F M /
I R I S G 1 1 5 E / T U T O R T . 1
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FOR SIMULATION PURPOSES ONLY
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Set the throttle carefully before starting the engine. This will ensure
that the engine is not started at a high power setting before the
lubrication system is able to operate fully.
•
Use smooth throttle movements, taking approx. 3 seconds to
change from idle to full or the reverse.
•
Do not slam the throttle closed or hold the throttle back against the
idle stop.
•
Avoid RPM / MP combinations that cause over boosting and
detonation damage. A placard lists the maximum MP settings.
Alternatively, avoid a MP higher than (RPM ÷ 100) plus 3½.
•
Monitor the engine instruments and take prompt action to avoid
limitations being exceeded.
Mixture Control
Control of the engine fuel/air mixture is achieved by adjusting the fuel flow
with the Mixture lever. Moving the mixture lever forward enriches the mixture
and increases fuel flow and vice versa.
Moving the lever aft, to the fully lean position, will shut off fuel completely,
causing the engine to stop. The three mixture settings relevant to Tutor
operations are Best Power Mixture (BPM), Best Economy Mixture (BEM) and
Endurance.
BPM.
This setting is used for almost all training exercises flown on the
Tutor. Before take-off, with the aircraft stationary and full power
applied, adjust the mixture to the placard altitude fuel flow, less 4 lph;
i.e. at sea level set 55 lph. In flight, with full power and HIGH RPM
selected, confirm that the fuel flow corresponds to the placard altitude
value, interpolating the value and adjusting the mixture if necessary.
BPM is now set for all throttle settings. Pilots should be aware, however,
that setting BPM at higher altitudes might lead to rough running on
descent.
BEM.
This setting is rarely used in normal Tutor operations and then only
at 75% power or less. If flying for maximum range and into a strong
headwind, some advantage may be obtained by setting BEM.
