[Turbine] Question about generator behavior
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Hello all,
On the turbine duke, the following behavior surprised me:
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If propeller is feathered and GEN is off, ELEC system runs off batteries, 0AMP & 24V (so far so good), but;
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If propeller is feathered & GEN is on, indicator shows 0AMP but 28+V (batteries are charging but no amps?) and GEN caution light is ON
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If propeller is unfeathered & GEN is on, we have an AMP reading, GEN caution line goes off;
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Electrical load on the generator does not seem to affect NG rpm;
So yeah, my main curiosity is about point 2. Why is the caution light there with props feathered ? If the generator is supposed to stay offline when props are feathered, how come we see a voltage increase (when turning on GEN with props feathered) ?
Thanks,
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The short answer is that the MSFS electrical system erroneously controls generator output in free turbine engines as if the generator is connected to the propeller shaft, rather than the gas generator accessory gearbox. After learning some lessons from the King Air, I had to create my own electrical calculations, and cover up the many, many, poorly implemented features of the MSFS electrical simulation, and you're probably looking at one of those.
For example, in the King Air, the generators would indicate that they were online and functioning when the propellers were feathered and at low RPM; however, the resulting output power was so low that users would lose all aircraft power after draining their batteries shortly after startup. What you're seeing in the Duke was likely my attempt to avoid this scenario, but failure to mask all the effects by suppressing the lower current generator output voltage.
