Multiplex MERLIN Notice De Construction page 25

Install the remaining RC system components in the model in
the arrangement shown in the illustration. Note that the position
of these items determines the Centre of Gravity. Use the Velcro
(hook-and-loop) tape 20 + 21 to secure the parts.
7.2 Power-glider version, Fig. 24
Install the remaining RC system components in the model as
shown in the illustration, using the Velcro tape 20 + 21. For the
power-glider the receiver has to be installed further aft in the
fuselage; check that the cables are long enough to allow the
plugs and sockets to be connected outside the fuselage. The
speed controller can be secured in the space under the canopy.
7.3 Control surface settings (guide only!) and initial test-run
Control surface travels (measured at the widest point of the
control surface):
Ailerons:
Elevator:
Rudder:
Flaps:
Spoilers:
Elevator trim compensation:
Spoilers
Flaps
Motor
Centre of Gravity:
the wing root leading edge
Longitudinal dihedral:
(This setting is correct when the socket-head grubscrew is visible
through the hole in the side of the fuselage.)
Motor downthrust (fixed): approx. 10° down, sidethrust: 0°
Ensure that all the receiving system components are correctly
installed and connected. Check the control surface settings, and
the direction of rotation of all the servos. Ensure that none of the
electrical leads can foul or get tangled in the motor when it is
rotating (glue or tape them in place!). Check the direction of
motor rotation once again (injury hazard!).
The tailplane is at the correct neutral position when you can see
the socket-head grubscrew through the hole in the side of the
fuselage, as shown in Fig. 27. Before you tighten the grubscrew,
remember to check from the transmitter that the elevator servo
is exactly at neutral (centre)!
7.4 Replacing the elevator servo
Normally the servo will never need to be replaced, but if it should
develop a fault, cut along the narrow channel as shown in Fig.
22, and remove the "hatch" thus formed. Replace the servo, then
stick the hatch back in place with a few drops of cyano. If you use
a really sharp knife and work neatly, the repair will be virtually
invisible.
8. Rudder servo cover, Fig. 25
The rudder servo recess can now be sealed by applying the
sticker 6*. This is accomplished by cutting a piece of the decal
sheet backing paper (30 x 40 mm, rounded corners) and placing
it centrally over the appropriate sticker from the decal sheet. This
"hatch cover" can now be applied over the servo well. Please
ensure that the adhesive cannot possibly stick the servo output
arm, and prevent it moving!
9. Aileron servo fairings, Fig. 26
The aileron servo fairings 45 + 46 can now be stuck permanently
to the wing. Glue the two servo covers 36 to the top surface of the
wing panels.
10. Centre of Gravity position, Fig. 27
The CG can be corrected by adjusting the position of the flight
battery, and by adding a little additional ballast if required. The
CG must be located exactly 40 mm aft of the wing root leading
edge (i.e. exactly coincident with the servo lead channel).
11. Preparations for the first flight
Please wait for a day with as little breeze as possible for the
model's initial test-flight. The evenings hours are often ideal for
calm conditions. If this is your first radio-controlled model
aeroplane, look for an experienced model flyer who is prepared
to help you, as it is very difficult to master the skills all by yourself.
Locate the nearest model flying club or clubs and ask them for
suitable contacts. Your local model shop should be able to
furnish you with addresses of clubs. Our flight simulator for the
PC is a very useful aid for those first steps in model flying; the
simulator can be downloaded from our website www.multiplex-
12 / 6 mm +/-
rc.de at no charge. A suitable interface lead for MPX transmitters
6 / 6 mm +/-
(Order No. # 8 5153) can be obtained from your model shop.
12 / 12 mm +/-
< 4 mm down
12. Be sure to carry out a range check before the first flight!
7 mm up
Just before the flight, charge up the transmitter battery and the
flight pack using the recommended procedures. Ensure that
"your" channel is not already in use before you switch the
1 mm "down"
transmitter on. Ask your assistant to walk away from the model,
< 1 mm +/-
holding the transmitter. The transmitter aerial should be fitted
< 1 mm "down"
but completely collapsed. Your assistant should operate one of
approx. 40 mm aft of
the functions constantly while you watch the servos. The non-
controlled servos should stay motionless up to a range of about
1 - 1.5°
60 m, while the controlled one should follow the stick movements
smoothly and without any delay. Please note that this check can
only give reliable results if the radio band is clear of interference,
and if no other radio control transmitters are in use - even on
different channels. If the initial range check is successful, repeat
it with the motor running at "half-throttle". There should be no
more than a very slight reduction in effective radio range with the
motor turning. If you are not sure about anything, please don't
risk a flight. Send the whole system (including battery, switch
harness and servos) to the Service Department of your RC
system manufacturer and ask them to check it.
13. Important points prior to the first flight
Glider
A test-glide can provide a useful pointer to the model's trim: hold
it at shoulder-height and push it forward firmly into any breeze. If
the model veers to one side, apply opposite rudder trim to correct
it. If one wing hangs down, you need to correct the aileron trim.
Flying at the slope
Ridge soaring is an extremely attractive form of model flying.
Flying for hours on end in slope lift, without needing any outside
aid for launching, must be one of the finest of modelling
experiences. But to fly out over the valley, search for a thermal,
"milk" the lift to the limits of vision (take care: the model is small!),
bring it down again in a continuous series of aerobatic
manoeuvres, and then to repeat the whole show - that must
surely be the last word in model flying.
But take care - there are dangers for your model lurking at the
slope. Firstly, in most cases landing is much more difficult than
at a flat field site. It is usually necessary to land in the lee of the
hill where the air is turbulent; this calls for concentration and a
confident, high-speed approach. A landing on the slope face, i.e.
right in the slope lift, is even more difficult. Here the trick is to
approach slightly downwind, up the slope, and flare at exactly
the right moment, just before touch-down.
Electric flight
The electric-powered version gives you the maximum measure
of independence: from a flat field you can reach a sensible height
25