Troy Built Models B-25 Mitchell User manual

SAFETY PRECAUTIONS
INSTRUCTION MANUAL
First-time builders should seek advice from people having building
experience.If misused or abused,it can cause serious bodily injury
and damage to property.
Fly only in open areas and preferably at a dedicated R/C flying site.
We suggest having a qualified instructor carefully inspect your
airplane before its first flight.Please carefully read and follow all
instructions included with this airplane,your radio control system
and any other components purchased separately.
(The people under 18 years old is forbidden from flying this model)
This R/C airplane is not a toy!
B-25 Mitchell
Specification:
Length :1935 mm(76.2")
Wing Span :2420 mm(95")
Wing Area :77.6 sq. dm
7.82/sq.ft
Wing Loading :128 g/sq. dm
42 oz/sq. ft
Flying Weight :10 kg(22.1 lbs)
Radio :6ch&13 servos
Engine(a pair) :91 4-cycle

: 4-cycle .91
14"x7
Spinner nut
6
(with 13 servos),
6
6
6 channel radio for aiplane is highly recommended for this model.
Warning
Remove the covering with proper
pressure to cut through only the covering itself.Otherwise,
cutting down into the balsa structure may weaken the
model part and cause accident.
The pre-covered film on ARF kits may wrinkle due to
variations of temperature.Smooth out as explained right.
Apply
Pre-cover the covering with clean cloth!
Start at low setting. Increase the setting if
necessary.If it is too high,you may damage
the film.
Iow setting
with cover(cloth)

1mm
Aileron
Trailing
edge
Make sure they are in
the right position while
installing.
Securely glue together. If coming off during flights, you 'll
lose control of your airplane which leads to accidents!
Make sure hinges are
mounted in the same line.
6
Pin hinge(24x24mm)
8
6
2
2
2
4
2
2
2
2
Clevis
Rod (2x300mm)
Retainer
TP Screw (2.3x12mm)
Wooden Block (20x20x8mm)
Servo tray(68.5x56.5x2mm)
Pin hinge(24x24mm)
Screw (3x40mm)
Washer(3x15mm)
2
Washer(3x15mm)
Lock Nut (3mm )
Clevis
Retainer Rod (2x300mm)
Screw (2x10mm)
Install the nylon control horn and connect the linkage.
Install the servo as the illustration below
Apply instant type CA glue to aileron and pin hinge.
Keep 1mm width space between aileron and trailing edge.
Assemble the aileron to main wing with instant
type CA glue.
1
2
3
4
5
1
Accessory list for the coming installation steps.
3-way
pressure inlet
Air tank
3-way
pressure inlet
3-way
pressure inlet
3-way
pressure inlet
3-way
pressure inlet
Switch
Air inlet
Strut
Strut
Strut
Quick release connector
Make sure to assemble retracts as instructed below.
Three wheel retract system
Quick release connector
Pressure reduction inlet
Ø1.7mm
Ø0.2mm
The status when the
gear up
Pull out length of 8mm
to make gear down
Air valve Air valve
Pleas notice the inner diameter for each
side of the pressure reduction inlet.
Please insure the sealing of the retract
system before flight .
3-way pressure inlet 5
1
Air tank
1
Air inlet
2
1
1
Air line (3000mm)
2
Quick release connector
Strut
( 90 )
1
Strut ( 110 )
Switch
Clevis
Rod (2X300mm)
1
1
1
Retainer
TP Screw(2.6x14mm) 2

8
TP Screw (2.3x12mm)
1.5mm
Pin hinge(36x20x1mm)
PVC
PVC Securely glue together. If coming off during flights, you 'll
lose control of your airplane which leads to accidents!
4
3mm
Pin hinge(36x20x1mm)
16
4
4
4
4
4
4
4
4
Clevis
Rod (2x300mm)
Retainer
TP Screw (2.3x12mm)
Wooden Block (20x20x8mm)
Servo tray(68.5x56.5x2mm)
Screw (3x50mm)
Washer(3x15mm)
4
1
2
Washer(3x15mm)
Lock Nut (3mm )
Rod (2x300mm)
Clevis
Washer(3x15mm)
Washer
Lock Nut (3mm )
Screw (3x40mm)
Flap
1mm
Make sure they are in
the right position while
installing.
Trailing
edge
Screw (2x10mm)
Install the servo as the illustration below
Secure the servo.Install the nylon control horn and
connect the linkage.
Epoxy the pin hinges to the flap.
Leave some space with width of 1mm between
trailing edge and flap.
Be careful to ensure the moving parts of the hinges
are able to move freely. Epoxy the flap to the main wings.
7
68
9
10
2
Accessory list for the coming installation steps.
85mm
Centre of Gravity.
96
19

TP Screw (2.3x12mm)
4
1.5mm
2mm
Pin hinge(36x20x1mm)
Clevis
Retainer
Rod (2x300mm)
Rod (2x300mm)
Clevis
Washer(3x15mm)
Washer
Lock Nut (3mm )
Screw (3x50mm)
Flap
1mm
Make sure they are in
the right position while
installing.
Trailing
edge
Screw (2x10mm)
Screw (2x10mm)
Securely glue together. If coming off during flights, you 'll
lose control of your airplane which leads to accidents!
Install the servo as the illustration below
Epoxy the flap to the mid wing.
Install the nylon control horn and connect the linkage.
Epoxy the pin hinges to the flap.
Secure the servo.Install the nylon control horn and
connect the linkage.
Keep some space of 1mm width between the flap
and trailing edge.
12
13
11
16
3
15
14
Epoxy the nose landing gear to appropriate position
inside the fuselage.
Top view
Position for
right diagram.
ELEVATOR
Side View
20mm
20mm
Adjustment.
Top view
Side View
25mm
25mm
RUDDER
Adjustment.
AILERON
40mm
FLAP
20mm
20mm
Side View
AILERON FLAP
Adjustment.
95
93
96
92
97
18
94

TP Screw (2.3x12mm)
Blind Nut (4mm)
2
Engine mount (106x86mm)
Linkage Stopper
8
8
24
8
Washer(4x8mm)
Screw (4x35mm)
Spring Washer (4mm)
Nut (4mm)
4
8
Screw (4x25mm)
4
Plastic tube (2x400mm)
Fuel tank (550cc) 2
8
3mm
Hook screw 2
1.5mm
Rod (2x300mm)
Clevis
Washer(3x15mm)
Washer
Lock Nut (3mm )
Screw (3x50mm)
Clevis
Retainer
Rod (2x300mm)
Screw (2x10mm)
Screw (2x10mm)
PVC
2
PVC
1
75mm
Install the nylon control horn and connect the linkage.
Secure the servo.Install the nylon control horn
and connect the linkage.
Cut off the surplus portion carefully along the shaded line.
Glue these PVC parts to relevant position on
the wings with CA glue.
Glue this PVC part to relevant position on the right wing.
18
19
20
21
4
17
Accessory list for the coming installation steps.
Ply (30x30x9mm) 2
4
Rubber band
Mount the receiver and the battery to the fuselage.
Landing gear 1
2
Copper joiner
Clevis 2
(5mm)
Collar (5mm) 7
2
Steel wire (0.5x1500mm)
1
Wheel (75 mm)
2
Wheel (115 mm)
TP Screw(3x20mm) 8
1
Landing gear (5mm)
1
Wooden Block(56x29x26mm)
Wooden Block(89x29x14mm) 1
Landing gear straps 4
2
Ally nose arm
42mm
1
decorate
Epoxy the decoration part to the fuselage carefully as
below.
Steel wire
Copper joiner
Aluminum tube
Clevis
Add a rubber ring to the
clevis for insuring safety
Collar (5mm)
Collar (5mm)
Collar (5mm)
Collar 4mm 3
Epoxy the main landing gear to the side fuselage.
Install the nose landing gear as below.
Collar (5mm)
Wooden supporter
Collar (5mm)
TP Screw (3x20mm)
8
3x20mm TP Screw
Landing gear straps 4
Collar 4mm 4
Install the main landing gear and fix it to the wooden
supporter steadily.
91
89
90
87
88
17
Accessory list for the coming installation steps.

PVC Part 2
PVC Part 2
Epoxy the PVC part to the fuselage carefully as below.
Epoxy the PVC part to the fuselage carefully as below.
PVC Part 2
Epoxy the PVC part to the fuselage carefully as below.
1.5mm
8
1
8
TP Screw (2.3x8mm)
PVC Part
Ply (15x15X3mm)
PVC Part 1
PVC Part 1
75mm
280mm
Epoxy the PVC part to the fuselage carefully as below.
Epoxy plies to appropriate position in the fuselage under
the PVC part and assemble the PCV part to the fuselage
with TP screw as illustration.
Epoxy the PVC part to appropriate position in the
fuselage as illustration.
82
81
83
84
85
86
16
Accessory list for the coming installation steps.
147 mm
5.2mm
Blind Nut
4
Blind Nut (4mm)
Washer (4x8mm)
Washer (4x8mm)
Washer (4x8mm)
Screw (4x35mm)
Screw (4x25mm)
Nut (4mm)
Spring Washer (4mm)
4mm
Set Screw (3x4mm)
Set Screw (2mm)
Rod (2x400mm)
Set Screw (2mm)
Washer (2mm)
Linkage Stopper 2
Set Screw (3x4mm)
2
2
2
In case of 2-cycle & 4-cycle engine.
Assemble the engine as below.
Assemble the accelerator push rod to the engine.
Fix the hook screw to wood block and epoxy the wood block
to appropriate position in the side faselage as below.
The sketch map of the the push rod assemble
completion
The front view and side view when the engine install
completion.
Drill four holes as show for engine mount.
22
23
24
25
26
5
21
Hook screw
2
2
Rubber band

16mm
PVC Part
1
PVC Part
1
PVC Part
1
25
25
TP Screw (2.3x8mm)
PVC Part
2
PVC Part
2
PVC Part
2
Decorate
1
Ply (15x15x3mm)
1.5mm
8
8
TP Screw (2.3x8mm)
Ply (15x15X3mm)
1.5mm
9
1
9
TP Screw (2.3x8mm)
PVC Part
Ply (15x15X3mm)
PVC Part 1
Assemble the switch servo to the fuselage.
Epoxy the belly pant to main wing and drill holes to
relevant position on the belly pant.
Cut off the surplus part carefully along the shaded
line.
Epoxy plies to appropriate position in the fuselage which
under the fiber part and assemble the fiber part to fuselage
with screw.
Epoxy plies to appropriate position in the fiber part under
the PVC part and assemble the PVC part to fiber parts
with TP screw as illustration.
76 78
77 79
80
15
Accessory list for the coming installation steps.
Linkage Stopper
Washer (2mm)
Washer (2mm)
Nut (2mm)
Nut (2mm)
Set screw (3x4mm)
Set screw (3x4mm)
2
2
2
2
Fuel tank (550cc) 2
Washer (4x12mm) 2
4
Blind Nut (4mm)
8
TP Screw (3x20mm) 26
TP Screw ( 2.3x8mm)
Ply (15x15x3mm) 26
Nut (4mm)
Wheel (115mm)
Note:rubber wheels oleo struts
and retracts are optional.
2
Nut (5mm )
2
Wheel (110 mm)
2
Nut (4mm )
28
2
Wheel (115 mm)
Decorate
Wood dowel (468x50x3mm) 2
Reinforcement Plate 2
2
Screw (4x45mm)
2
Screw (4x75mm)
Fuel supply line
Fuel spray line
Air pressure line
Bushing (8X4mm)
2
Bushing (8X4mm)
2
Bushing (8X4mm)
Install the servo.
Assemble the throttle servos in the fuselage.
Assembly of the fuel tank.
Assemble the rear wheels.
28
29 32
6
27
Accessory list for the coming installation steps.
Assembly of the fuel tank
31

Assemble the horizontal tail to fuselage as below.
1.5mm
6
TP Screw (2.3x8mm)
PVC Part 1
Assemble the canopy to the canopy mount with
screw.
Ply (10x10x2mm) 4
Cut off the surplus part carefully along the shaded
line.
4
TP Screw (3x20mm)
1.5mm
Install the nose landing gear to appropriate
position in the fuselage.
10mm
16
TP Screw ( 2.3x8mm)
Ply (15x15x3mm)
16
1.5mm
2
2
2
Clevis
Copper joiner
Aluminum tube(3x6mm)
2
2
Screw (2x10mm)
Nut (2mm )
2
Washer(2x5mm)
Steel wire
Copper joiner
Aluminum tube Lock Nut (2mm )
Screw (2x10mm)
Ball joint
Washer(2x5mm)
Assemble the steeling fullarm around the landing gear.
Install the servo.
Add a rubber ring to the
clevis for insuring safety
Assembly of the switch servo.
Trim the surplus portion for assemble the nose gear freely.
Epoxy plies to appropriate position in the fuselage which
under the nose gear cover and assemble the nose gear
cover to fuselage with screw.
71
72
70
74
75
14
73
1.5mm
10
TP Screw (2.3x8mm)
Ply (15x15x3mm) 10
1.5mm
16
TP Screw ( 2.3x8mm)
Ply (15x15x3mm)
16
28
Decorate
Epoxy the plies under the covering and assemble
it to side fuselage with screw.
Trim the cowling for engine and muffler.
epoxy the ply under cowling and assemble the
cowling to side fuselage.
34
35
36
37
38
7
33
1.5mm
TP Screw(3x20mm) 8
Assemble the main landing gear. Cut off the surplus parts carefully along the
shaded line the and epoxy them to yhe cowling.
Drill holes at appropriate position in the wing for fetching
out the servo wire and air pipe.

4
Wood dowel (6x50mm)
2
Screw(4x35mm)
Screw(4x35mm)
2
Screw(4x75mm) Screw(4x75mm)
6.2mm
Blind Nut
6.2mm
Blind Nut
4
Blind Nut (4mm)
2
Reinforcement
5mm 5mm
A = A"
A"
A
Wood dowel (468x50x3mm) 2
Drill holes on the wing root accorrding to rib template.
Hook screw 2
Hook
Rib template (2mm ply)
2
1
6mm
6mm
Rib template (3mm ply)
1
2
Main wing joiner(25x350mm)
The standard sketch map when the main wing install
completion.
Epoxy the side fuselage to the mid wing steadily.
According to the reinforcement drill four holes to
appropriate position in the mid wing and set blind
nut in relevant fuselage position.
Fix the mid wing to the fuselage with the screws
as illustration.
40
41
42
8
39
43
Accessory list for the coming installation steps.
Bushing (8X6mm)
Nut (4mm)
1
Nut (4mm )
1
Wheel (75mm)
Wheel (75 mm)
1
Aluminum part(60x6mm)
Aluminum part(60x6mm)
Assemble the nose wheel.
1
Bushing (8X6mm)
3.2mm
Blind Nut
80mm
160mm
2
Washer(3x6mm)
Washer(3x6mm)
2
Screw (3x40mm)
Screw (3x40mm)
2
Blind Nut (3mm)
24
TP Screw ( 2.3x8mm)
Ply (15x15x3mm)
24
2
Clevis
2
2
Screw (2x10mm)
Nut (2mm )
2
Steel wire (0.5x1500mm)
4
2
2
Clevis
Copper joiner
Aluminum tube(3x6mm)
TP Screw (3x20mm) 4
8
TP Screw (2.3x12mm)
1
Aluminum part(60x6mm)
1
Nut (4mm )
1
Wheel (75 mm)
2
Washer(2x5mm)
1
Bushing (8X6mm)
Assmble the stabilizer to the tail of fuselage with screw.
Cut off the surplus portion carefully along the shaded line.
Glue this PVC part to appropriate position on the
stabilizer with CA glue.
Put the stabilizer to appropriate position on the fuselage
and drill holes through the PVC,stabilizer until fuselage.
67
68
69
13
66
65
Accessory list for the coming installation steps.

2
Wood dowel (6x50mm)
2
Blind Nut (3mm)
2
Washer(3x6mm)
1
PVC
2
Screw (3x40mm)
TP Screw (2.3x12mm)
1.5mm
3mm
Clevis
Retainer
Rod (2x300mm)
Rod (2x300mm)
Clevis
Washer(3x15mm)
Washer
Lock Nut (3mm )
Screw (3x40mm)
Screw (2x10mm)
Screw (2x10mm)
50mm
10mm
6mm
50mm
10mm
6mm
2
Wood dowel (6x50mm)
20mm
Drill holes to appropriate position in the lead edge of
stabilizer and epoxy wood dowels in them.
Drill two holes to appropriate position in the
fuselage as illustration.
62
63
64
12
61
60
Accessory list for the coming installation steps.
The position of the control horn in the rudder.
Secure the servo,install the nylon control horn
and connect the linkage.
Install the nylon control horn and connect the
linkage.
8
8
2
2
2
2
2
2
2
2
Clevis
Rod (2x300mm)
Retainer
TP Screw (2.3x12mm)
Wooden Block (20x20x8mm)
Servo tray(68.5x56.5x2mm)
Pin hinge(24x24mm)
Screw (3x40mm)
Washer(3x15mm)
2
Washer(3x15mm)
Lock Nut (3mm )
1
Tailplane servo mount
44
46
45
47
9
48
Accessory list for the coming installation steps.
4
Wood dowel (6x50mm)
1.5mm
60.5mm
Hook screw
Epoxy the wood dowel in the holes and set the hook
screw to appropriate position
2
Rib template (3mm ply)
1
6mm
2
Main wing joiner(24x350mm)
2
Drill holes to relevant position in the side fuselage
according to rib template as below.
Drag the wing and the side fuselage together with the
hook and rubber band.
Assmble the wing to the side fuselage tightly.
Hook
Make sure to glue securely.
If not properly glued, a failure in flight may occur.
Temporarily fasten down the main wing and
check its correct position.
Securely glue together.If coming off during flights,
you'll lose control of your airplane which leads
to accidents!
The standard sketch map will be as below when the
horizontal tail install completion.
BB’
B=B’

27mm
32mm
4
Pin hinge(24x24mm)
Make sure hinges are
mounted in the same line.
Add a rubber ring to the
clevis for insuring safety
Apply instant type CA glue to rudder and pin hinge.
Assemnle the servo of the elevator.
Trim the covering carefully to appropriate position in the
tailplane and epoxy the tailplane servo mount to the ready
slot as illustration.
1
Tailplane servo mount
49
51
52
53
54
10
50
4
Pin hinge(24x24mm)
Make sure hinges are
mounted in the same line.
3mm
35mm
Drill one small hole at appropriale position and Apply
instand type CA glue to elevator and pin higes.
1mm
Elevator
Make sure they are in
the right position while
installing.
Make sure they are in
the right position while
installing.
Trailing
edge
Keep some space about 1mm width between the
elevator and horizontal tail edge.
Assmble the elevator to the stabilizer with CA gule and
the metal wire with epoxy glue.
Securely glue together. If coming off during flights, you 'll
lose control of your airplane which leads to accidents!
The standard sketch map will be as below when
the horizontal tail install completion.
Make sure to glue securely.
If not properly glued, a failure in flight may occur.
Temporarily fasten down the main wing and
check its correct position.
Securely glue together.If coming off during flights,
you'll lose control of your airplane which leads
to accidents!
C
DD’
C’
56
57
55
58
57
11
59
Polish the surface flat.
Epoxy the vertical tail to the stabilizer.
Install the medium servo as below.
1mm
Rudder
Tailing
edge
Make sure they are in
the right position while
installing.
4
Pin hinge(24x24mm)
Securely glue together. If coming off during flights, you 'll
lose control of your airplane which leads to accidents!
Keep 1mm width space between horizontal tail and
rudder.
Assemble the rudder to the vertical tail with CA glue.
Cut off the surplus portion from the vertical tail carefully.
C=C’
D=D’