Durafly P-51D OLD CROW Parts list manual

Please read this manual carefully before operating this plane.
P-51D OLD CROW (PNF)

Read the ENTIRE instruction manual to become familiar with the features of the product
before operating. Failure to operate the product correctly can result in damage to the product,
personal property and cause serious injury.
This is a sophisticated hobby product and NOT a toy. It must be operated with caution and
common sense and requires some basic mechanical ability. Failure to operate this Product in a
safe and responsible manner could result in injury or damage to the product or other property.
This product is not intended for use by children without direct adult supervision.
This manual contains instructions for safety, operation and maintenance. It is essential to read
and follow all the instructions and warnings in this manual prior to assembly, setup, or use, in
order to operate correctly and avoid damage or serious injury.
As the user of this product, you are solely responsible for operating in a manner that does not
endanger yourself and others or result in damage to the product or the property of others. This
model is controlled by a radio signal subject to interference from many sources outside your
control. This interference can cause momentary loss of control so it is advisable to always
keep a safe distance in all directions around your model, as this margin will help avoid
collisions or injury.
Age Recommendation: Not for children under 14 years. This is not a toy.
• Never operate your model with low transmitter batteries.
• Always operate your model in an open area away from cars, traffic or people.
• Avoid operating your model in the street where injury or damage can occur.
• Never operate the model in the street or in populated areas for any reason.
• Carefully follow the directions and warnings for this and any optional support equipment
(chargers, rechargeable battery packs, etc.) you use.
• Keep all chemicals, small parts and anything electrical out of the reach of children.
• Moisture causes damage to electronics. Avoid water exposure to all equipment not
specifically designed and protected for this purpose.
• Never lick or place any portion of your model in your mouth as it could cause serious injury
or even death.
WARNING:
SAFETY PRECAUTIONS AND WARNINGS:

TABLE OF CONTENTS
Kit contents ........................................................................................................................... 1
The spare parts list ............................................................................................................... 1
Spare parts list content .......................................................................................................1-2
The illustration of the spare parts ......................................................................................... 2
Charging the Flight Battery ................................................................................................... 3
Low Voltage Cutoff (LVC) ..................................................................................................... 3
Fuselage/tail assembly ......................................................................................................... 4
Install the control horn ........................................................................................................4-5
Connect the Y harness to the main wing .............................................................................. 6
Install the Horizontal stabilizer .............................................................................................. 6
Electronics installation and set-up ........................................................................................ 7
Bind the receiver to the transmitter ........................................................................................7
Install the receiver ................................................................................................................. 7
Install the battery .................................................................................................................. 8
Hook on the linkage rod of the stabilizer .............................................................................. 8
Test the stabilizer control servos .......................................................................................... 8
Electronics installation and set-up ........................................................................................ 9
Main wing assembly, set-up and installation .................................................................. 10-12
Install the control rod ........................................................................................................... 10
Test the retract and the LED set .......................................................................................... 11
Install the oil tank ................................................................................................................. 11
Mount the main wing ........................................................................................................... 12
Final assembly and set-up procedures .......................................................................... 13-21
Important ESC and model information ................................................................................ 13
The transmitter and model set up .................................................................................. 14-15
Check the control throws ............................................................................................... 16-17
Install the propeller set .................................................................................................. 17-18
Install the antenna mast ...................................................................................................... 18
Check the C.G . (Center of Gravity) .................................................................................... 21
Before flying the model ....................................................................................................... 22
Find a suitable flying site .................................................................................................... 22
Perform the range check of your plane .............................................................................. 22
Monitor your flight time ....................................................................................................... 22
Flying the your model ......................................................................................................... 23
Take off ............................................................................................................................... 23
Flying .................................................................................................................................. 23
Landing ............................................................................................................................... 23
Maintenance ....................................................................................................................... 23
Troubleshooting .................................................................................................................. 24

TABLE OF CONTENTS
Kit contents ........................................................................................................................... 1
The spare parts list ............................................................................................................... 1
Spare parts list content .......................................................................................................1-2
The illustration of the spare parts ......................................................................................... 2
Charging the Flight Battery ................................................................................................... 3
Low Voltage Cutoff (LVC) ..................................................................................................... 3
Fuselage/tail assembly ......................................................................................................... 4
Install the control horn ........................................................................................................4-5
Connect the Y harness to the main wing .............................................................................. 6
Install the Horizontal stabilizer .............................................................................................. 6
Electronics installation and set-up ........................................................................................ 7
Bind the receiver to the transmitter ........................................................................................7
Install the receiver ................................................................................................................. 7
Install the battery .................................................................................................................. 8
Hook on the linkage rod of the stabilizer .............................................................................. 8
Test the stabilizer control servos .......................................................................................... 8
Electronics installation and set-up ........................................................................................ 9
Main wing assembly, set-up and installation .................................................................. 10-12
Install the control rod ........................................................................................................... 10
Test the retract and the LED set .......................................................................................... 11
Install the oil tank ................................................................................................................. 11
Mount the main wing ........................................................................................................... 12
Final assembly and set-up procedures .......................................................................... 13-21
Important ESC and model information ................................................................................ 13
The transmitter and model set up .................................................................................. 14-15
Check the control throws ............................................................................................... 16-17
Install the propeller set .................................................................................................. 17-18
Install the antenna mast ...................................................................................................... 18
Check the C.G . (Center of Gravity) .................................................................................... 21
Before flying the model ....................................................................................................... 22
Find a suitable flying site .................................................................................................... 22
Perform the range check of your plane .............................................................................. 22
Monitor your flight time ....................................................................................................... 22
Flying the your model ......................................................................................................... 23
Take off ............................................................................................................................... 23
Flying .................................................................................................................................. 23
Landing ............................................................................................................................... 23
Maintenance ....................................................................................................................... 23
Troubleshooting .................................................................................................................. 24
88 P-51D OLD CROW 1
KIT CONTENTS
1. The fuselage assembly (With the motor, the canopy, the electronic parts, ESC)
2. Main wing ( With all electric device installed)
3. Horizontal stabilizer with elevator joiner installed
4. canopy (with pilot)
5. Propeller, spinner set, and the antenna mast
6. Spare parts bag
7. Fuel tank
THE SPARE PARTS LIST
Replacement parts for the Durafly P -51D are available using the order numbers
in the Spare parts list that follows. The fastest, most economical service can be provided
by your hobby dealer or mail-order company.
SPARE PARTS LIST CONTENT
Spare parts list content
43509 Fuselage (With all the plastic parts and rudder installed)
43515 Main wing (With the control horn in stored)
43518 Horizontal stabilizer ( With the elevator joiner installed)
43521 Canopy (Plastic canopy)
43523 Cowl
43525 Spinner Main landing gear strut (With the fairing and the tires)

23387 Rear landing gear (With the tire)
21029 Propeller
23389 X Motor base Decal sheet
23391 Motor shaft
23392 Motor board
23393 Pilot
NOTE: All of the parts are painted with no decal applied.
THE ILLUSTRATION OF THE SPARE PARTS
2

88 P-51D OLD CROW 3
CHARGING THE FLIGHT BATTERY
CAUTION: All instructions and warnings must be followed exactly. Mishandling of Li-Po
batteries can result in fire, personal injury, or property damage.
BATTERY WARNING:
● By handling, charging or using the included Li-Po battery you assume all risks associated
with lithium batteries.
● If at any time the batteries begin to swell, or balloon, discontinue use immediately!
Charging or discharging a swelling or ballooning battery can result in fire.
● Always store the batteries at room temperature in a dry area to extend the life of the
battery. Always transport or temporarily store the battery in a temperature range of
40-120˚F. Do not store battery or model in a car or in direct sunlight. If stored in a hot car,
the battery can be damaged or even catch fire.
● Never use a Ni-Mh charger. Failure to charge the battery with a compatible charger may
cause fire resulting in personal injury and property damage.
● Never discharge Li-Po cells to below 3V.
● Never leave charging batteries unattended.
● Never charge damaged batteries.
CHARGING THE FLIGHT BATTERY
When charging the battery, make certain the battery is on a heat-resistent surface, charge
the battery before assembly of the airplane. Install the fully charged battery to perform
control tests and binding.
LOW VOLTAGE CUT OFF (LVC)
When a Li-Po is discharged below 3V per cell, it will not hold a charge. The ESC protects
the flight battery from over-discharge using Low Voltage Cutoff. Before the battery charge
decreases too much, LVC removes power from motor in two ways: (1) Reduces power -
ESC reduces motor power (recommended), (2) Hard cutoff - ESC instantly cuts motor
power when the pre-set Low Voltage Protection Threshold value is reached. These
settings can be changed using the ESC programing guide.

4
FUSELAGE / TAIL ASSEMBLY
INSTALL THE CONTROL HORN
1. Attached the control horn to the
starboard of the rudder with it
toward the hinge line.
3. Check to make sure the screws are
firmly grabbed into the horns.
4. Install the aileron control horn on
the servo side of the main wing with
the horn towards the hinge line as
the picture shows.
2. Secure the horn from the backplate
side using the provided screws.
NOTE: The longer screws always
locate on the leading edge side of
all the control surface.
1.1
2
3
4.1
4.2
1.2

88 P-51D OLD CROW 5
ASSEMBLE THE PLANE
INSTALL THE CONTROL HORN
1. Attach the flap control horn on the servo
side of the main wing with the horn
towards the hinge line.
1.1
3. Secure the horn using the provided
screws from the backplate side.
NOTE: The longer screws for secure
the horns always located on the
leading side of the surface.
3
4. Make sure the screws firmly into the
backplate.
Note: Do not over tighten the screws,
but make sure they are tight enough.
4
1.1
Flaps
2
2. Secure the horn from the backplate
using the provided screws.
NOTE: No backplate used in this step or
it will stop the flap from fully retract.

6
3. Connect the wing leads to the harness
the first. Two ailerons servo to the Y
harness labeled AILE (CH1), main
landing gears to the harness with GEAR
(CH5), two LED leads and the flaps to the
four way harness labeled FLAP (CH6).
Secure the connector using the tape.
1. Apply glue to the horizontal stabilizer
halves where it mating with the mounting
Groove.
NOTE: leave it for one minute after
applying glue to the horizontal stabilizer
for better gluing before inserting to tail.
3.1
3.2
3.3
INSTALL THE HORIZONTAL STABILIZER
AileronsAilerons
Gears
Gears
Flaps
Flaps
1.1 1.2
2. Insert the starboard stabilizer half
into the tail mounting slot the same with
the port side half.
2.1
3. Check to make sure the stabilizes is
standing fully vertical with the vertical
fin. Adjust any misalignment before the
glue dried throughly.
90o
ASSEMBLE THE PLANE
CONNECT THE Y HARNESS
TO THE MAIN WING

88 P-51D OLD CROW 7
1. Before getting started, bind your receiver
with your transmitter. Please refer to your
Transmitter Manual for proper operation.
CAUTION: To prevent personal injury,
DO NOT install the propeller assembly onto
the motor shaft while binding the receiver to
your transmitter and in all the testing steps
until the manual tell you to do it .
3. Note: All servo and retract leads have
been specifically labeled for your
convenience. Use the provided
Y-harness for situations where two or
three servos are controlled by one
channel; for example ailerons, landing
gear, and flaps. Refer to the diagram
bellow for recommended connections.
Receiver connection diagram.
4. Attach the receiver to the receiver
chamber in front of the tail servo using
double side tape or velcro tape
1. Remove the canopy by rising the band on
the rear end of the cover.
2. Disconnect the battery from the ESC
after the binding process completed.
Turn off the transmitter and remove the
bind plug as necessary. Plug the elevator
and the rudder servos to the receiver.
INSTALL THE RECEIVER
ELECTRONICS INSTALLATION AND SET-UP
BIND THE RECEIVER TO THE TRANSMITTER
1
2
ReceiverY-harness
Aileron
Aileron
Channel-1
Aile
Elevator
Channel-2
Ele
Throttle Channel-3
Thro
Rudder
Steering Channel-4
Rudd
Landing Gear
Landing Gear
Channel-5
Gear
Flap
LED
Flap
LED
Channel-6
Aux1
4

8
1. Slide the battery into the battery hatch with
the power supply cable toward the rear end
of the plane and secure it using the pre
installed hook and loop tape.
NOTE: You may need to relocate the
battery position to achieve the correct CG
for your model.
3. The provided piece of fuel tubing keeps
the clevis closed during flight. Secure all
the linkages the same way.
NOTE: Do not over slide the securing
tube or it will impede the movement
of the surface control horn. Install all
of the linkages the same way.
1. Make sure all the control sticks on your radio are in the neutral position (rudder, elevator,
ailerons) and the throttle in the OFF position. Turn on the transmitter and power on the
model, move the elevator and the rudder on the transmitter to make sure aircraft control
surface move orrectly. If controls respond in the opposite direction, reverse the direction
for operation of flight controls.
4. Repeat the step 2&3 for the all the other
linkage hooking.
1. Loose the screws on the control connector
which holding the rod into place.
TEST THE STABILIZER CONTROL SERVOS
HOOK ON THE LINKAGE
ROD OF THE STABILIZER
ELECTRONICS INSTALLATION AND SET-UP
INSTALL THE BATTERY
1
1
2. Snap the clevis into the elevator surface
control horn.
2
3

88 P-51D OLD CROW 9
4. Adjust the control connector on the rear
landing gear steering arm to make sure
the wheel align with the centerline of the
fuselage.
2. Make sure all the control surface trim in
neutral position, for computerized
transmitters, use the servo/channel
sub-trim feature to make each servo
arm fully vertical.
NOTE: Make sure the trims and the sub
trims in neutral position before making
some mechanically trim. Adjust the
servo arms mechanically make sure all
all servo arms are as fully vertical with
the servo case as possible. If not,
adjust the servo arm by using the trim
function on your radio.
5. The motor should rotat counterclockwise
when viewing the plane from the front.
Or you will have to disconnect any two of
the motor plugs and plug them back to
each other’s socket.
ELECTRONICS INSTALLATION AND SET-UP
3. Adjust the linkage in the control
connector to make sure the
counterbalance leading edge of the
elevator and the rudder level with the
leading edge of the horizon stabilizer
and the vertical fin respectively.
NOTE: Use a drop of thread lock on the
screw before secure the rod into place.
1.2
1.1
Elevator up/Stick downElevator up/Stick down
Elevator down/Stick up
Elevator down/Stick up
Rudder left/Stick leftRudder left/Stick leftRudder left/Stick leftRudder left/Stick left Rudder Right/Stick rightRudder Right/Stick right
3.1 Elevator
Rudder
Elevator
Rudder
5
4

10
1. The standard hole settings for linkage
connections are shown by the black
arrows in the diagram below. You can
refer the recommended control threw
setting to move the linkage to different
hole positions to increase control
surface travel and increase the
aerobatics of the airplane.
3. Toggle switch the flaps channel knob
according to which AUX port that the Y
harness you have inserted into the receiver.
NOTE: To avoid the “buzz” sound from the
flap servos, install either the flaps linkage
while the servo arm in up position. And
make sure the trailing edge of the flaps
level with the wing root.
4. Thread the folks on the linkage rod clockwise
and counterclockwise to make sure the flaps
are at right position when the folk closed.
2. Make sure the aileron servo horns are
fully vertical with the servo case and
stick Input the aileron to make sure the
servos functions well. Put the Z-bend
end of the linkage into the desired servo
control horn hole of the main-wing. It is
a tight fit and should allow the linkage to
move just slightly within the hole to
avoid binding up. Hook on the clevis
the same with the stabilizer.
MAIN WING ASSEMBLY, SET-UP AND INSTALLATION
INSTALL THE CONTROL ROD
Increase
IncreaseIncrease
Decrease
DecreaseDecrease
Servoarm Control horn
2
3.1
Flap servo in
down position
Flap servo in
down position
3.2
Flap servo
in up position
Flap servo
in up position
4

88 P-51D OLD CROW 11
1. Cycle the retractable main landing gears
several times to ensure proper function.
2. Make sure the navigation light on port
side(L) wing tip emitting red beams, the
starboard(R) is green.
1. Slide the oil tank into place as the
picture shows.
MAIN WING ASSEMBLY, SET-UP AND INSTALLATION
TEST THE RETRACT AND THE LED SET INSTALL THE OIL TANK
LR
1
2
1.1
1.2

12
MAIN WING ASSEMBLY, SET-UP AND INSTALLATION
MOUNT THE MAIN WING
1. Seat wing to the wing bay by threading
the leads from the hole at the bottom of
the wing bay to the receiver hatch,
2. Slightly pull the leads from the receiver
hatch before fully fit the main wing into
place to avoid any tangling to prevent
the wing from fully mounting.
1
2
3. Check to make sure the main wing
before secure it into place using the
provided self tapping screws, two pieces
PWM 3*45 (A) to hold the wing front into
place. The PWM 3*50(B) pieces are
used to secure the rear side of the wing
into place.
AB
3

88 P-51D OLD CROW 13
FINAL ASSEMBLY AND SET-UP PROCEDURES
IMPORTANT ESC AND MODEL INFORMATION
1. The ESC included with the P -51 has a safe start. If the motor battery is connected to
the ESC and the throttle stick is not in the low throttle or off position, the motor will not
start until the throttle stick is moved to the low throttle or off position. Once the throttle
stick is moved to the low throttle o off position, the motor will emit a series of beeps.
Several beeps with the same tune means the ESC has detect the cells of the battery.
The count of the beeps equal the cells of the battery. The motor is now armed and will
start when the throttle is moved.
2. The motor and ESC come pre-connected and the motor rotation should be correct.
If for any reason the motor is rotating in the wrong direction, simply reverse two of the
three motor wires to change the direction of rotation.
3. The motor has an optional brake setting. The ESC comes with the brake switched off
and we recommended that the P -51 be flown with the brake off . However, the brake
could be accidentally switched on if the motor battery is connected to the ESC while the
throttle stick is set at full throttle. To switch the brake off, move the throttle stick to full
throttle and plug in the motor battery. The motor will beep one time. Move the throttle
stick to low throttle or the off position. The motor is ready to run and the brake will be
switched off.
4.Battery Selection and Installation. We recommend the 11.1V 2200mAh 25C(180g/6.3oz)
Li-Po battery. If using another battery, the battery must be at least a 11.1V 2200mAh 25C
battery. Your battery should be approximately the same capacity ,dimension and
weight as the 11.1V 2200mAh 25C Li-Po battery to fit in the fuselage without changing
the center of gravity significantly.
5. The specification of the model list as fellow:
Wing span: 1100mm / 43.3in
Length: 970mm / 37.2in
Motor: 3 536-K V750
ESC: 35A with integrated 3 A BEC
Battery: 11.1V 2200mAh 25C
Servo: 9g*6
Approx fying weight: 1220g
Propeller: 10*8 four blades scale propeller
Wing area: 20.3dm2
Wing loading: 60.1 g/dm2

14
FINAL ASSEMBLY AND SET-UP PROCEDURES
THE TRANSMITTER AND MODEL SETUP
Before getting started, rebind your receiver with your transmitter if necessary.
CAUTION: To prevent personal injury, DO NOT install the propeller assembly onto the
motor shaft while testing the control surfaces.
TIPS: Make sure all control sticks on your radio are in the neutral position (rudder, elevator,
ailerons) and the throttle in the OFF position. Make sure both ailerons
move up and down (travel) the same amount. This model tracks well when the
left and right ailerons travel the same amount in response to the control stick.
1. Move the controls on the transmitter to make sure aircraft control surface move
correctly. See diagrams below. If controls respond in the opposite direction reverse
the direction for operation of flight controls. Refer to your transmitter’s instructions
for changing direction of transmitter flight controls.
Bank Left
Bank Right
Climb
Descend
Yaw Left
Yaw Right
Aileron
Elevator
Rudder /
Steering

88 P-51D OLD CROW 15
FINAL ASSEMBLY AND SET-UP PROCEDURES
2. Recheck to align the control surfaces well by trim the control channel.
The ailerons align with the trailing edge of the wing tip.
2.1 2.2
2.3 2.4
AileronAileron ElevatorElevator
Rubber
Rubber

16
FINAL ASSEMBLY AND SET-UP PROCEDURES
CHECK THE CONTROL THROWS
1. Adjust ATV/travel adjustment on your transmitter until you obtain the following control
surface travel. Do not adjust dual rates until you have correctly adjusted the total travel.
AILERONS: 16mm up and down (both ailerons), measured at the aileron inboard side.
ELEVATOR: 12mm up and down, measured at the counterbalance leading edge.
RUDDER: 12mm left and right, measured at the counterbalance leading edge.
FLAPS: Full 25mm
2. The dual rates and the Exponential setting for intermediate flyers of P -51 are based on
the ATV set in previous step.
2.3 2.4
High Rate
100% 20mm left/right
100% 16mm up/down
100% 16mm up/down
Rudder
Elevator
Aileron
25%
25%
30%
Expo
15%
20%
20%
Expo
75% 15mm left/right
63% 10mm up/down
69% 11mm up/down
Low Rate
2.1
AileronAileron
2.2
ElevatorElevator
Rubber
Rubber FlapFlap

88 P-51D OLD CROW 17
INSTALL THE PROPELLER SET
CAUTION: Disconnect the battery from the
ESC before installing the propeller. Before
testing the propeller, make sure the tail of
the plane is firmly on the ground and
ensure there are no people or objects in
the range of the propeller. Make sure the
throttle stick and the trim on the lowest
position before plug in the battery.
1. Keyed the propeller assembly onto the
hex nut of the motor shaft properly.
2. Install the propeller to the motor shaft
and make sure the root of the propeller
sit right on the saddle with the paint side
face the front of the plane. Install the nut
and make sure the nut is tight enough to
the propeller.
FINAL ASSEMBLY AND SET-UP PROCEDURES
NOTE: 1. This control throws were developed by R&D department for the best
performance of the P -51. The small mount of elevator throw on low rate is
capable of extreme aerobatics.
2. At first flight, fly the model in low rate. The first time you use high rates, be sure
to fly at low to medium speeds. High rates, as listed, are only for EXTREME
maneuvering. Only switch to high rate when the plane is flying at slow speed.
Never fly at high speed at full air speed. This plane is very responsive and pilot
can easily lose orientation. Get familiar with the plane first and then try high rate.
3. For take off and landing, low rate in all control surfaces is strongly recommended.
1.1
1.2
2.1
2.2