The batteries will have to be positioned to suit the Centre of Gravity, and are normally the last
items to be installed. Don’t forget that you might wish to alter the C of G position a little after
the first few trimming flights, so try to allow for some adjustment. Normally a thin plywood, or
thick balsa, plate can be glued into position, and the Nicads secured to it with cable-ties or
Velcro straps.
Of course it is extremely important that both the fuel tank and batteries are mounted securely,
as the forces on these heavy items are large during aerobatic manoeuvres - when you are
pulling a 10G manoeuvre these items will, in effect, weigh 10 times their normal ‘static’ mass !
The receiver is a lightweight item and can be mounted on a foam rubber pad, and held in
place with rubber bands or double-sided Velcro straps. Of course it must still be easily accessi-
ble, as you may have to connect your aileron (and elevator) servo extension cables each time
you assemble the plane. Please make sure your receiver Crystal cannot accidentally come
loose by securing it with a piece of clear tape, or similar. In the case of contests you might also
have to change frequencies quite often, which also means that the receiver crystal should be
in an accessible position.
Motor Ignition System
If you are fitting a gas engine, we advise that you keep the ignition unit as far away from the
receiver and R/C equipment as possible. Generally you will be able to mount the ignition unit and
battery right in the nose, close the back of the firewall.
Fuel proofing
If fitting a gas or glow motor we highly recommend that you protect all the bare wood parts and
edges inside the front of the plane with one thin
coat of 24 hr laminating epoxy, or similar,
brushed on. Be careful not to add excess weight
here - it only needs about 25 grams (< 1 oz.) of
epoxy to fuel proof all the wood in the whole
area in the front of the plane.
Electric Power
We have done extensive testing with Electric
power, as this is becoming a very popular choice
in many countries now due to stricter noise reg-
ulations ... and we can tell you that the perform-
ance of our Impact with Electric power is
absolutely stunning.
We have a special ‘Electric option’ pack avail-
able, which will be an extremely common option
and this can be used for the Hacker C50 or
Plettenberg 25-13, or modified for other similar
units. This Option pack includes the main bulk-
heads and battery support parts required to
install either the Plettenberg Xtra 25-13 motor,
or the Hacker C50 geared unit, both powered by
LiPo batteries. Considerable flight testing and
demonstrations have been carried out with both
motors, both by factory staff and C-ARF
Composite-ARF IMPACT
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