J-Power Grob 120TP User instructions

Assembly and Operating Manual
Grob 120TP
Specification:
*Length:51‐2/5"(1305mm)
*Wingspan:66‐9/10"(1700mm)

*Flyingweight:2800g(98-4/5oz.)

Dear customer,
Congratulations on your choice of a
factory-assembled model aircraft from the
J-POWER LIGHT PLANE RANGE and thank you
for placing your trust in us.
The model can very quickly be completed ready to
fly. Please read right through these instructions
and the separate information sheets before
attempting to assemble and fly the model, as this
will make it much easier to complete the tasks
required.
All directions, such as “right-hand”, are as seen
from the tail of the model, looking forward.
Notes on the power system
Abrushless outrunner motor, propeller and spinner
are factory-installed.
The motor is connected to the speed controller,
ready to use, and the controller is correctly set up
at the factory.
To complete the power system all you have to do
is connect the LiPo flight battery.
The radio control system
For this model you require a radio control system
with at least four channels. We particularly
recommend 2.4 GHz systems.
The receiving system is powered by the speed
controller’s integral BEC system.
Before you check the model’s working systems,
set the control surfaces to neutral from the
transmitter (transmitter sticks and trims central).
Before operating the model always move the
throttle stick to the “motor stopped” position before
switching the transmitter on. Only then connect the
flight battery.
To switch off, first disconnect the flight pack from
the speed controller, and only then switch the
transmitter off.
Glued joints, suitable adhesives
Foam safe epoxy is recommended and available
from most reputable model retail shops.
Trial-fit all parts “dry” before applying glue.
Follow the recommended curing time suggested
by the glue manufacturer. Allow the glue to fully
cure (harden) to the point where the joint can be
placed under stress.
Kit contents
Fuselage, complete with motor, speed controller
and servo.
Integral wing panels with L.H / R.H. ailerons and
servos
Tailplane and elevator
Fin
Factory-fitted propeller and spinner
2 X Aileron pushrod, Two Z-bend
1 X Elevator pushrod, one Z-bend.
1 X Rudder pushrod one Z-bend
2 X Landing flaps pushrod Two Z-bend
5 X Y-lead
6 X Control surface horn
1 X 4S1P LiPo battery，3600 mAh, 25C

AssemblyandOperatingManual Grob120TP
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Figs. 1
-Picture shows the elevator surface ,control horns
and hinges .Assemble the control horns and
hinges to the elevator .
Figs. 2
- Cut up the elevator, drill hole in the location of
install hinges.
Fig. 3
-Photo shows the hinges assembled on the
elevator surface .
Fig. 4
- Photo shows the control horns assembled in the
elevator.
2
1
3 4

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Fig. 5
-Assemble the elevator to fuselage ,and screw up it .
Fig. 6
-Cut up the rudder , drill hole in the location of install
hinges
Fig. 7
-Assemble the hinges to the rudder surface
Fig. 8
- Connect the rudder lighting wire to the fuselage
and assemble the rudder to fuselage . .
7
6
8
5

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Fig. 9
-Fixed the vertical with screw .
Fig. 10
-Assemble the vertical to the fuselage .
Figs. 11
-Heat the shrink tube .to avoid the collet chuck
loosen
Figs. 12
- Cut up the rudder , drill hole in the location of install
hinges
10
11 12
9

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Figs. 13
-Assemble the hinges to the aileron .
Figs. 14
-Photo shows the hinges have settled in the aileron .
Figs. 15
-Photo shows the main wing support wood board..
Figs. 16
-Apply glue to the board .Assemble the board to the
main wings.
14
13
15 16

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Figs. 17
-Photo shows the main wing support bar have
installed in the wings .
-
Figs. 18
-Assemble the control rods to the left and right main
wings.
Figs. 19
- Assemble the control rods to the left and right
aileron
Figs. 20
-Assemble the main wings to the fuselage .and lock
it with screws .
1817
19 20

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Figs. 21
- Assemble the propellers and spinner cover with
screws .
Figs. 22
-Photo shows the propellers connected on the
cover .
Figs. 23
-Assemble the propellers on the motor .
Figs. 24
-Photo shows the finished view.
22
21
23 24

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Figs. 25
-Assemble the spinner to the spinner cover .lock it
with screw .
Figs. 25
-Photo shows the accessories
Figs. 27
-Assemble accessories A,C and G to the Vertical fin .
Figs. 28
-Assemble accessories D,H and E to the fuselage .
26
27
28
25

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Figs. 29
-Assemble the accessory B to the nosing of the
plane .
Figs. 30
-Assemble the accessory F to the main wing .
Figs. 31
-Assemble the accessory I to the main wing .
Figs. 32
- Connect the channel wire leads to the receiver .and
located the battery.
30
31 32
29

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Figs. 33
- Congratulations, you have completed the
assembly process. We hope you enjoy flying your
new model!
Figs. 34- Photo shows the balancing weight.
- Place the canopy on the fuselage.
- Place the battery in the model of balancing; do not
connect it.
- Make the Centre of Gravity on both sides.
- Support the model at the marked C.G. and allow it
to hang freely. The model is correctly balanced
when it hangs level, ideally with the nose inclined
slightly down.
- Adjust the position of the flight battery if necessary.
- Mark the battery location in the fuselage, so that
you can be confident of replacing it in the same
position after removing it.
33
34

AssemblyandOperatingManual Grob120TP
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Fig.35
-Charge the flight battery; connect the Equalizer
lead using and adapter lead matching your charger
(adapter lead not included).
Fig.36
- Switch the transmitter on, and move the throttle
stick to the “Motor OFF” position. (Diagram MODE
1 right throttle control stick)
35
36

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Fig.37-40 Function test
- Check the channel assignment at the receiver, and if
necessary swap the plugs as necessary.
- Set the transmitter sticks and trims to centre.
- The control surfaces should now also be at centre (neutral).
Adjust the clevis where necessary.
- Check the direction of rotation of the servos.
- Stand behind the model. - When you move the rudder stick
to the right, the rudder should also deflect to the right.
- Pull the elevator stick back towards you, and the rear edge
of the elevator should rise.
- Moving the aileron stick to the right, you MUST check that
the trailing edge of the right aileron rises, the left aileron
should go down.
- If any function works the wrong way round, correct it using
the servo reverse facility on your transmitter.
- Set the control throw using the transmitter servo end point
adjustment function.
- The travels are measured at the inboard end of the control
surfaces.
- The stated control throws are just a guide for the first few
flights. You will probably need to adjust the actual settings
to suit your individual flying style.
- The Expo settings should also be adjusted to suit the pilot's
preference.
39
37 38
40

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Fig. 41 checking the electric power system
- Caution: position the throttle stick in such a way
that the motor cannot possibly start running.
41

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- Switch the transmitter on, and connect the
flight pack Check the direction of rotation of
the motor: when viewed from the front, the
output shaft must rotate anti-clockwise. If this is
not the case, perhaps because you are using
components other than those recommended,
swap over any two motor wires to reverse the
direction of rotation.
Note: whenever you are installing, adjusting
or servicing the power system,
keep well clear of the rotational
plane of the propeller –injury
hazard. Ensure also that
nobody stands in front of the
model when the motor is running.
- First disconnect the battery from the speed
controller, and then switch the transmitter
off.
- The model is ready for flying once you have
recharged the battery.
Test-flying, flying notes
Read the sections in the Safety
Notes entitled “Routine pre-flight
checks”and “Flying the model”
before attempting to fly the model
for the first time.
- Advice on control surface travels
- The stated control surface travels are just a
guide for the first few flights. Every pilot will need
to adjust the settings slightly to suit his or her
individual flying style. Exponential settings
should also be set to suit your personal
preference.
- For your first few flights please wait for a day
with no more than a gentle breeze.
- A good flying site consists of a large, flat, open
grassy field, devoid of trees, fences,
high-tension overhead cables etc.
- Repeat the check of all the working systems.
- Ask an experienced modeling friend to
hand-launch the aircraft for you. He should be
capable of giving the model a reasonably strong,
flat launch.
- The model must be launched directly into any
wind.
- With the motor running at full-throttle, give the
aeroplane a firm launch directly into any breeze,
with the fuselage and wings level.
- Allow the Grob120TP to fly straight ahead
initially; don’t initiate turns close to the ground.
- Adjust the control surface trims if necessary, so
that the model flies straight with a reasonable
rate of climb “hands off”.
- Check the model’s reaction to control inputs. If
necessary, you may need to increase or reduce
the control surface travels after the first landing.
- Check the aeroplane’s stalling speed at a safe
height.
- Keep the model’s speed well above the stall for
the landing approach.
- If you needed to adjust the trims during the
test-flight, correct the length of the appropriate
pushrod once the model is back on the ground,
then return the transmitter trims to centre so that
full trim travel is available to both sides of neutral
for subsequent flights.
- We reserve the right to introduce technical
modifications and suggest that you check our
website for updates.

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J-POWER GROUP CO.,LTD
5th Floor, A3 Building, Xinjianxing Technology Industrial Park, Fengxin Road,
Guangming Town, Bao'an, Shenzhen City, 518107 China
Phone: [phone]
Fax: [phone]
www.jpower.hk