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Operating a model helicopter for the first time
Even if you already know „all there is to know» about model helicopters please read the following notes carefully:
Before operating the model check the following points:
- The direction of servo rotation (including the throttle function) and travels.
- The direction of effect of the gyro, and the transmitter mixer functions you have programmed.
- Collective pitch travel (linear travel -2/-3° to +9/+10°); rotor diameter 2000 mm Ø plus: 0° to +10°
- It is permissible to reduce servo travels, but not below 60% (in this case adjust the mechanical linkage); travels should
be primarily symmetrical.
- Apply collective pitch min. / collective pitch max. and full roll and pitch-axis commands simultaneously in all directions;
rotate the rotor head at the same time, and check that at the extremes of travel no part of the rotor head is obstructed,
and the collective pitch compensator guide pin does not foul the swashplate.
- Check the safe connection of the ball link of the swashplate driver before each flight, if the rotor head is using one.
- The auto-rotation switch must be assigned, and within easy reach!
- When auto-rotation is selected: throttle position to off, all directions of control and travels as in normal flight, tail rotor to
0° = fixed value.
- Do not set the tail rotor gyro to work in „heading-lock mode» initially.
- Contrary to the information supplied by many gyro manufacturers, the greater inertia of larger helicopters means that
they do need the support of tail rotor mixer functions in normal mode.
- Tail rotor position 0° at collective pitch min.; at collective pitch max. the tail rotor blade tips should be about 50 - 60 mm
apart when the blades are folded together in the blade holders.
- Set the motor distinctly „rich», and set the throttle curve very low: the throttle curve should then be raised gradually
in small increments, and the motor cautiously „leaned out» until the correct rotor speed level is reached; i.e. work
„upwards» towards the correct speed!
- The first few tankfuls should be flown with the model close to the ground, i.e. no more than about 1 m altitude, until you
are confident that there are no defects or errors, and that everything is working faultlessly:
- Use your ears critically (!), listening for unusual sounds and vibration, and seek out the problem if you are in any doubt
at all!
- Don't listen to anyone standing close by if they try to hurry you into flying the model.
- Avoid hovering outside ground effect (hover altitude with a model: approx. 1 m, or half the rotor disc diameter):
- Hovering requires very high power, and you are completely dependent on the motor: in contrast to most full-size
helicopters, model helicopters have only one (!) power plant.
- If your rotor head features a swashplate driver, check that the ball-link is secured properly and functioning correctly
before every (!) flight.
For the first few circuits: starting from ground effect, accelerate to a moderate speed in level flight, and only then initiate a
climb (this is the only way to ensure that you can land safely at any time if the motor fails); always keep the model flying at
a brisk forward speed; on the landing approach always descend towards the landing area at a steady angle (around 45°)
directly into wind, and don't bring the model to a halt until it is in ground effect again.
à Even if everything is actually working properly, you may still find that the helicopter balloons up on the descent
- especially if the system rotational speed is allowed to rise (idle-up set too high !). If this happens, there are two
solutions available to you: immediately move collective pitch to the hover position, and resume the descent using the
pitch-axis function only (i.e. reduce height by flying circles at a low rate of descent); the alternative is to carry out an
auto-rotation landing immediately.
à Immediately means within the first second.
à Before flying you should deliberately practise mentally what you need to do in particular situations.
à If one particular technical fault keeps recurring in your model, replacing the component concerned will not solve the
problem unless you change some other aspect of the operating conditions.
And one final request:
à
Please be realistic when assessing your piloting skills. Keep this comparison in mind: if you can't swim and
you dive into deep water, the chances are that you will drown.
Technische Änderungen vorbehalten / Subject to technical changes
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