Shutting Down The Turbine; Automatic Shut Down Of The Turbine (Autooff); Automatic Post-Run Cooling Process - GRAUPNER JetCat P60 Instructions D'utilisation

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Shutting down the turbine

There are two methods of shutting the turbine down:
Immediate shut-down of the turbine - emergency stop (Manual Off)
The turbine can be shut down immediately at any time:
•
By moving the 3-position switch to the OFF position (switch back)
or
•
By moving the throttle stick to idle, and the throttle trim to OFF (back).

Automatic shut down of the turbine (AutoOff)

The turbine should normally be shut down in the following way:
Move the 3-position switch forward (position 2 = AutoOff)
This causes the following events to occur:
The turbine stabilises at a speed of around 55,000 rpm, and after about 6 seconds is then shut
down.
The advantage of this procedure is that the turbine is running at its optimum temperature range
before being shut down, and the relatively high rotational speed ensures that a large quantity of
cooling air is drawn through the engine before it actually comes to a halt. The automatic shut-
down process can be interrupted at any time by moving the 3-position switch back to the centre
setting before the engine has actually stopped.

Automatic post-run cooling process

The turbine starter motor is used to spin the turbine after it has been shut down. This process automatically
cools the engine, and continues until the turbine exhaust gas temperature is below about 100°C.
Caution:
In exceptional situations the pilot can switch off the automatic post-run cooling process by:
Moving the 3-position switch to OFF, and moving the throttle stick to idle, and moving the
throttle trim to OFF (back).
Switching off the post-run cooling process may be necessary in exceptional situations, e.g.: if the
model crashes and burns - in this case the post-run cooling process would pump extra oxygen into the
model, and only make the fire worse.
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