Great Planes GPMA1131 User Manual

INSTRUCTION MANUAL

Wingspan: 32 in [820mm]
Length: 36.5 in [920mm]
Wing Area: 270 in2 [17.4dm2]
Weight: 5.5 – 6.7oz [155-190 g]
Wing Loading: 2.9-3.5 oz/sq ft [9-11 g/dm2]
Motor: RimFire 250 (28-23-1750) or RimFire 300 (28-22-1380) brushless out-runner motor with Silver Series 8A ESC.
Radio: 4 channel transmitter, 3 micro servos

WARRANTY

Great Planes® Model Manufacturing Co. guarantees this kit to

be free from defects in both material and workmanship at the date
of purchase. This warranty does not cover any component parts
damaged by use or modification. In no case shall Great Planes’
liability exceed the original cost of the purchased kit. Further,
Great Planes reserves the right to change or modify this warranty
without notice.

In that Great Planes has no control over the final assembly or
material used for final assembly, no liability shall be assumed nor
accepted for any damage resulting from the use by the user of
the final user-assembled product. By the act of using the user­assembled product, the user accepts all resulting liability.

If the buyer is not prepared to accept the liability associated
with the use of this product, the buyer is advised to return

this kit immediately in new and unused condition to the place
of purchase.

To make a warranty claim send the defective part or item to Hobby
Services at the address below:

Hobby Services

3002 N. Apollo Dr., Suite 1

Champaign, IL 61822 USA

Include a letter stating your name, return shipping address, as
much contact information as possible (daytime telephone number,
fax number, e-mail address), a detailed description of the prob­lem and a photocopy of the purchase receipt. Upon receipt of the
package, the problem will be evaluated as quickly as possible.

READ THROUGH THIS MANUAL BEFORE STARTING CONSTRUCTION. IT CONTAINS IMPORTANT INSTRUCTIONS

AND WARNINGS CONCERNING THE ASSEMBLY AND USE OF THIS MODEL.

Champaign, Illinois

[phone], Ext 5

[e-mail]

Entire Contents © Copyright 2008 GPMA1131 Mnl 1.0

TABLE OF CONTENTS

AMA

INTRODUCTION ................................2

AMA .......................................2

SAFETY PRECAUTIONS .........................2

DECISIONS YOU MUST MAKE.....................3

Radio Equipment .............................3

Power System Recommendations ................3

Charger ....................................3

ADDITIONAL ITEMS REQUIRED ...................4

Required Hardware and Accessories .............4

Adhesives and Building Supplies.................4

Optional Supplies and Tools.....................4

IMPORTANT BUILDING NOTES....................4

KIT INSPECTION................................4

KIT CONTENTS.................................5

PREPARATIONS ................................6

BUILD THE FUSELAGE ..........................6

INSTALL THE SERVOS AND PUSHRODS ...........11

INSTALLING THE MOTOR AND RADIO GEAR .......16

GET THE MODEL READY TO FLY .................18

Check the Control Directions ...................18

Set the Control Throws........................18

Balance the Model (C.G.)......................19

PREFLIGHT ...................................19

Identify Your Model...........................19

Charge the Batteries .........................19

Balance Propellers...........................20

Range Check ...............................20

MOTOR SAFETY PRECAUTIONS .................20

AMA SAFETY CODE (excerpts)...................21

General ...................................21

Radio Control ...............................21

CHECK LIST ..................................21

FLYING.......................................22

Takeoff ....................................22

Flight .....................................22

Landing ...................................22

We urge you to join the AMA (Academy of Model Aeronautics)
and a local R/C club. The AMA is the governing body of model
aviation and membership is required to fly at AMA clubs.
Though joining the AMA provides many benefits, one of the
primary reasons to join is liability protection. Coverage is not
limited to flying at contests or on the club field. It even applies
to flying at public demonstrations and air shows. Failure to
comply with the Safety Code (excerpts printed in the back of
the manual) may endanger insurance coverage. Additionally,
training programs and instructors are available at AMA club
sites to help you get started the right way. There are over
2,500 AMA chartered clubs across the country. Contact the
AMA at the address or toll-free phone number below:

Academy of Model Aeronautics

5151 East Memorial Drive
Muncie, IN 47302-9252
Tele. [phone]
Fax [phone]
Or via the Internet at:
http://www.modelaircraft.org

IMPORTANT!!!

Two of the most important things you can do to preserve the
radio controlled aircraft hobby are to avoid flying near full­scale aircraft and avoid flying near or over groups of people.

PROTECT YOUR MODEL, YOURSELF

& OTHERS.....FOLLOW THESE

IMPORTANT SAFETY PRECAUTIONS

1. Your Yak 54 should not be considered a toy, but rather a
sophisticated, working model that functions very much like
a full-size airplane. Because of its performance capabilities,
the Yak 54, if not assembled and operated correctly, could
possibly cause injury to yourself or spectators and damage
to property.

INTRODUCTION

Congratulations on your purchase of the Great Planes Yak
54 3D Indoor EP ARF! This Yak 54 is a great flying model
and is suitable for both indoor and calm day outdoor flying.
It’s capable of the most extreme 3D maneuvers, but is still a
very precise and durable airplane.

For the latest technical updates or manual corrections to the
Yak 54 3D Indoor EP ARF visit the Great Planes web site
at www.greatplanes.com. Open the “Airplanes” link, then
select the Yak 54 3D Indoor EP ARF. If there is new technical
information or changes to this model a “tech notice” box will
appear in the upper left corner of the page.

2. You must assemble the model according to the
instructions. Do not alter or modify the model, as doing so
may result in an unsafe or unflyable model. In a few cases
the instructions may differ slightly from the photos. In those
instances the written instructions should be considered as
correct.

3. You must take time to build straight, true and strong.

4. You must use an R/C radio system that is in first-class
condition, and a correctly sized motor and components
(battery, wheels, etc.) throughout the building process.

5. You must correctly install all R/C and other components
so that the model operates correctly on the ground and in
the air.

2

6. You must check the operation of the model before every
flight to insure that all equipment is operating and that the
model has remained structurally sound. Be sure to check
clevises or other connectors often and replace them if they
show any signs of wear or fatigue.

7. If you are not an experienced pilot or have not flown
this type of model before, we recommend that you get the
assistance of an experienced pilot in your R/C club for
your first flights. If you’re not a member of a club, your local
hobby shop has information about clubs in your area whose
membership includes experienced pilots.

Versatile Setup

3 Futaba

o

(FU TM0414)

Futaba

o

Receiver (FUTL7627)

®

S3114 Micro High Torque Servo

®

R617FS 7-Channel 2.4GHz FASST

Power System Recommendations

8. While this kit has been flight tested to exceed normal use,
if the plane will be used for extremely high stress flying, such
as racing, or if a motor larger than one in the recommended
range is used, the modeler is responsible for taking steps to
reinforce the high stress points and/or substituting hardware
more suitable for the increased stress.

We, as the kit manufacturer, provide you with a top quality,
thoroughly tested kit and instructions, but ultimately the
quality and flyability of your finished model depends
on how you build it; therefore, we cannot in any way
guarantee the performance of your completed model,
and no representations are expressed or implied as to
the performance or safety of your completed model.

Remember: Take your time and follow the instructions to
end up with a well-built model that is straight and true.

DECISIONS YOU MUST MAKE

This is a partial list of items required to finish the Yak 54
3D Indoor EP ARF that may require planning or decision
making before starting to build. Order numbers are provided
in parentheses.

Radio Equipment

The Yak 54 3D Indoor EP ARF requires a minimum 4-channel
radio system with three micro servos having a rating of at
least 20 oz-in [1.5 kg-cm].

In addition, a micro receiver will also be needed. Two different
radio setups have been provided below. The lightweight
setup utilizes micro Futaba servo connectors. The versatile
setup utilizes standard Futaba servo connectors. The part
numbers are also provided below:

Lightweight Setup

o

o

OR

3 Futaba

Micro Plug (FUTM0704)

Futaba

(FUTL7626)

®

S3114M Micro High Torque Servo w/

®

R616FFM FASST Micro Receiver

The recommended motor size for the Yak 54 is the RimFire
250 (28-23-1750) brushless out-runner motor. The RimFire
300 (28-22-1380) brushless motor would also be a good
choice, if you are planning to fly the Yak 54 outdoors.

Great Planes Silver Series 8A Brushless ESC 5V/

o

BEC (GPMM1840)

Great Planes RimFire 250 (28-23-1750) Brushless

o

Out-runner Motor (GPMG4502)

Great Planes ElectriFly

o

Competition BP Series (GPMP0700)

OR

Great Planes RimFire 300 (28-22-1380) Brushless

o

Out-runner Motor (GPMG4505)

Great Planes ElectriFly

o

Competition BP Series (GPMP0701)

™

LiPo 7.4V 300mAh 20C

™

LiPo 11.1V 300mAh 20C

Charger

A LiPo compatable charger is required to charge LiPo
batteries. The Great Planes PolyCharge4
LiPo packs only; however, it is able to charge four LiPo packs
simultaneously. The Great Planes Triton2
charge one pack at a time, but is capable of charging NiCd,
NiMH, Pb acid, and LiPo batteries. Order numbers for both
are provided below:

Great Planes PolyCharge4

o

Charger (GPMM3015)

OR

Great Planes ElectriFly Triton2

o

Charger (GPMM3153)

Throughout the life of a LiPo battery, the individual cells
located inside the battery may become unbalanced. These
unbalanced cells can shorten the life of the battery or cause
it to malfunction. For this reason, it is always recommended
that a cell balancer be used when charging LiPo batteries.
The Electrifly Equinox
with any LiPo charger and is capable of maintaining the cell
balance of the battery.

Great Planes ElectriFly

o

1-5 (GPMM3160)

3

™

is a cell balancer that may be used

™

DC Only 4 Output LiPo

™

Equinox LiPo Cell Balancer

™

is designed for

™

charger will only

™

DC Comp Peak

ADDITIONAL ITEMS REQUIRED

IMPORTANT BUILDING NOTES

Required Hardware and Accessories

This is a partial list of the hardware and accessories
required to finish the Yak 54. Order numbers are provided
in parentheses:

Adhesives and Building Supplies

This is the list of Adhesives and Building Supplies that are
required to finish the Yak 54:

Foam Safe CA+ Medium Glue 2oz (GPMR6070)

o

2 oz spray CA activator (GPMR6035)

o

8 oz Foam Safe Activator Refill 8oz (GPMR6036)

o

Masking tape (TOPR8018)

o

#1 Hobby knife (HCAR0105)

o

#11 blades (5-pack, HCAR0211)

o

Hobbico Soldering Iron 30 Watt (HCAR0775)

o

• Self-tapping screws are designated by

a number and a length. For example,
#6 x 3/4" [19mm].

• When you see the term test fit in the instructions,

it means that you should first position the part on the
assembly without using any glue, then slightly modify
or custom fit the part as necessary for the best fit.

• Whenever the term glue is written you should use foam

safe CA glue.

• Photos and sketches are placed before the step they

refer to. Frequently you can study photos in following
steps to get another view of the same parts.

• The stabilizer and wing incidences and motor thrust

angles have been factory-built into this model. However,
some technically-minded modelers may wish to check
these measurements anyway. To view this information
visit the web site at www.greatplanes.com and click on
“Technical Data.” Due to manufacturing tolerances which
will have little or no effect on the way your model will fly,
please expect slight deviations between your model and
the published values.

Optional Supplies and Tools

Here is a list of optional tools that will help you build
the Yak 54:

Threadlocker thread locking cement (GPMR6060)

o

CA applicator tips (HCAR3780)

o

CA debonder (GPMR6039)

o

Pliers with wire cutter (HCAR0630)

o

Hobbico Duster

o

Precision Magnetic Prop Balancer (TOPQ5700)

o

Hobbico Flexible 18" Ruler Stainless Steel

o

(HCAR0460)

Hobbico Pin Vise 1/16 Collet w/6 Bits (HCAR0696)

o

Great Planes Pro

o

X-Acto

o

®

Extra Hands Double Clip (XACR4214)

™

can of compressed air (HCAR5500)

™

CA Glue Thin 1oz (GPMR6002)

KIT INSPECTION

Before starting to build, take an inventory of this kit to
make sure it is complete, and inspect the parts to make
sure they are of acceptable quality. If any parts are missing
or are not of acceptable quality, or if you need assistance
with assembly, contact Product Support. When reporting
defective or missing parts, use the part names exactly as
they are written in the Kit Contents list.

Great Planes Product Support:
3002 N Apollo Drive, Suite 1
Champaign, IL 61822

Telephone: [phone], ext. 5
Fax: [phone]
E-mail: [e-mail]

4

KIT CONTENTS

1

2

4

3

1. Vertical fuselage and rudder

2. Fuselage stringers

3. Landing gear assembly

5

Kit Contents

4. Aft horizontal fuselage

5. Forward horizontal fuselage and wing

To convert inches to millimeters, multiply inches by 25.4 (25.4mm = 1")

5

PREPARATION S

1. If you have not done so already, remove the major parts

o 

of the kit from the box and inspect for damage. If any parts
are damaged or missing, contact Product Support at the
address or telephone number listed in the “Kit Inspection”
section on page 4.

BUILD THE FUSELAGE

1. Locate the two ABS landing gear stiffeners. Glue a

o 

landing gear stiffener to each side of the fuselage in the
location shown.

3. Key the rear of the horizontal fuselage into the

o 

vertical fuselage. Then key the wing portion into the
vertical fuselage.

2. Remove the twelve fuselage alignment jig pieces from

o 

their surrounding foam. Note: These pieces are labeled
1,2,3,4,6, and W. There are no pieces labeled 5.

6

4. On a flat, level work surface, place the base sections

o 

of alignment jig pieces number 1,3, and 4 underneath the
fuselage in the locations shown.

5. Test fit the top sections of the alignment jig pieces onto

o 

their corresponding bases. Install the motor mount onto the
front of the firewall, but DO NOT glue it in place at this time.
Connect the top portions of the jig pieces to their bases by
applying a small amount of foam safe CA glue to the tabs
that overlap. Be very careful to not glue the jig pieces to

the fuselage.

7

6. Place the base section of jig piece 2 under the wing, and

o 

place base jig piece 6 under the horizontal stabilizer. Slide
the corresponding top sections over the fuse, as pictured.

8. Apply a thin bead of foam safe CA glue to the

o 

opposite side of the fuselage, and to the seam behind the
wing. Activate this CA and allow a few moments for the
glue to cure.

9. Once the glue has cured, gently turn the Yak over and

o 

apply glue to the underside fuselage seams.

7. Glue the two fuselage pieces together by gently sliding

o 

the vertical fuselage and applying foam safe CA glue to the
seam between the two fuselage pieces. Be very careful when
gluing around the jig pieces. DO NOT glue the jig pieces to
the fuselage. Apply some foam safe accelerator to the seam,
and allow a few moments for the glue to cure.

8

10. Locate the two carbon brace supports. There is a slit

o 

located in the center of each wing. With the Yak on its back,
glue the carbon brace supports into the slits on the underside
of the wing. It is possible that, during manufacturing, some
glue has gotten into the slit. If this is the case, DO NOT
FORCE the carbon brace support into the slit. Simply clear
the glue with a hobby knife.

12. Slide the 13" [330mm] carbon rod through the aft

o 

fuselage slit. Thread a carbon brace doubler onto the rod
and thread the rod through the carbon brace support. Thread
a second carbon brace doubler onto the rod, and place the
carbon rod into the slit located close to the wing leading
edge. Glue the carbon rod into the wing. Slide the carbon
brace doubler over the slit, and glue it to the wing. DO NOT

glue the carbon to the fuselage or to the brace support
at this time. Repeat this step for the other side of the wing.

11. Locate the two 13-7/16" x 3/64" [340 x 1mm] carbon

o 

rods, and two 13" x 3/64" [330 x 1mm] carbon rods. Insert
a 13-7/16" [340mm] rod through the landing gear plate and
through the carbon brace support. Thread a plastic carbon
brace doubler onto the carbon rod. Place the end of the
carbon rod into the slit at the trailing edge of the wing. Glue
the carbon rod into the wing. Slide the carbon brace doubler
over the slit, and glue it to the wing. DO NOT glue the carbon
to the fuselage at this time. Repeat this step for the other
side of the wing.

13. Locate the two 6-3/16" [157mm]carbon rods. Thread

o 

two carbon brace doublers onto the rods. Place one end of
each rod into the slot on the fuselage and the other end of
the rod into the slot at the tip of the horizontal stabilizer. Glue
the rod to the horizontal stabilizer. Slide one of the carbon
brace doublers over the slit and glue it to the stabilizer. DO

NOT glue the carbon to the fuselage at this time.

9

14. Turn the Yak back, right side up. Locate the two jig

o 

pieces marked with a “W” and place them under the wings in
the location shown. With all the jig pieces in place, adjust the
carbon rods, if necessary, to be certain the wing and horizontal
stabilizer are level and straight. Once the wings and stab are
aligned, glue the carbon rods to the fuselage, and glue the
carbon brace doublers over the slits in the fuselage.

and into the slit at either tip of the horizontal stabilizer. Double
check the alignment of the vertical stabilizer and then glue
the carbon rods in place.

15. Allow a few moments for the glue to cure and then glue

o 

the carbon rods in the wing to the carbon brace supports.

16. Locate the two 7" [178mm] carbon rods. Slide these

o 

carbon rods through the slit in the top of the vertical stabilizer

17. Using a hobby knife, remove the top portion of

o 

assembly jig pieces 1, 2, and 4 that are close to the fuselage,
as shown. There should still be a small amount of the top
pieces left, to keep the jig attached to the fuselage.

10

INSTALL THE SERVOS

AND PUSHRODS

18. Locate the two fuselage stringers. Very gently, so as to

o 

not twist the fuselage, glue the stringer at a 45 degree angle
to the sides of the fuselage by applying a small amount of
glue to the beveled portion of the stringers. Once the glue
has had time to cure, reinforce the stringers by applying glue
to the seam between the stringers and the fuse halves.

19. At this point double check to make sure the motor

o 

mount is in the center of the airframe, and then glue it into
position. Carefully remove the bottom pieces of the build jig
by cutting or breaking them.

For your convenience, the aileron and elevator pushrods
have been pre-assembled. If you are not using Futaba
S3114 servos, or due to manufacturing tolerances, it may
be necessary to change the pushrod length. This may
be done by holding the heat shrink tubing that connects
the pushrod to the z-bend and gently rotating the z-bend
until the glue holding the z-bend in place has broken
loose. Then adjust the length by pulling or pushing the
z-bend until the appropriate length is achieved, and re­glue the z-bend to the pushrod using some CA glue.

11

1. Install the pre-assembled elevator pushrod by inserting

o 

the pushrod guides through the fuselage as shown. DO NOT
glue the pushrod guides in place at this time.

2. Locate your elevator servo. Remove the servo screw

o 

from the servo output shaft. Install the larger arm onto the
servo. Center the servo using your radio and, using some
diagonal pliers, remove the three extra servo arms.

4. Thread the z-bend onto the outer most hole of the servo

o 

arm. Note: If you are not using a computer radio, and do not
wish to set your model up with 3D control throws, you may
choose the hole that is most appropriate. When the servo
arm is installed correctly the pushrod will exit closest to the
fuselage, as shown. Finish the elevator servo installation by
centering the servo, placing the servo arm onto the servo,
and reinstalling the servo screw.

3. Install the elevator servo, without the servo arm, by

o 

placing it into the middle servo mount in the fuselage, with
the output shaft on the forward side as shown. NOTE:
Pay carefull attention to the servo position in this picture.
Glue the servo in place using some foam-safe CA glue.
Be careful to not get any glue inside the servo case. This
could ruin your servo.

12

6. Attach one of the included z-bends to the 21-11/16" x

o 

3/64" [550 x 1mm] carbon rudder pushrod, using one of the
provided 1" [25.4mm] lengths of heat shrink. Use a soldering
iron or heat gun to shrink the pushrod to the z-bend.

7. Use some foam safe CA to glue the foam servo doubler

o 

around the rudder servo slot. NOTE: The rudder servo
doubler should be glued on the opposite side of the fuselage
from the elevator servo.

5. Install the elevator control horn by first threading it onto

o 

the z-bend at the end of the elevator pushrod. Then place
some foam safe CA glue onto the base of the control horn.
Insert the pushrod into the slit in the elevator. The slit in the
control horn should fit over the carbon elevator joiner. If the
control horn will not fit over the carbon joiner, simply remove
the excess glue from the slit to achieve a snug fit.

8. Starting from the nose of the airframe, thread the

o 

rudder pushrod you have partially assembled through the 5
pushrod supports. The z-bend you have applied should end
up at the servo mount.

13

9. Install the rudder servo using the same method that

o 

was used to install the elevator servo. NOTE: The rudder
servo will be installed on the opposite side of the fuselage
from the elevator servo.

11. Thread a z-bend through the control horn, so that the

o 

pushrod mounts to the underside of the control horn. Place
one of the included pieces of heat shrink around the z-bend
and pushrod. Secure them together by shrinking the tubing
using a soldering iron. BE VERY CAREFUL when using the
soldering iron when very close to the foam. The foam will
melt if it is touched with a hot iron.

12. Re-center the rudder servo and adjust the length of the

o 

pushrod by moving the z-bends. Once the servo is centered
and the rudder is in the neutral position, further secure the
z-bends to the rudder pushrod using some CA glue.

10. Once the rudder servo has been installed and has

o 

been secured using some foam safe CA, locate a control
horn and glue it into the slit in the rudder, on the same side
as the rudder pushrod.

13. Align the pushrod guides so that they are perpendicular

o 

to the fuselage and keep the pushrods as straight as possible.
Then glue the pushrod guides to the fuselage using some
foam safe CA.

14

14. Locate the anti-differential arm and your aileron servo

o 

arm. Place the anti-differential arm on the underside of the
servo arm. If you are using Futaba servo arms, the holes
in the servo arm and the holes in the anti-differential arm
will align. If you are using another brand servo arm, you will
need to use a #60 [1mm] drill bit to drill a pilot hole through
the servo arm that will align the servo arm with the anti­differential arm.

15. Attach the anti-differential arm to the servo arm by

o 

inserting the provided 3/64" [1.2mm] servo screws through
the anti-differential arm and into the servo arm.

17. Attach one end of each pre-assembled 2mm aileron

o 

pushrod to either end of the anti-differential arm, and place
the servo arm onto the servo. Look closely at the picture to
determine the correct direction of the anti-differential arm.

18. Thread a control horn onto each end of the aileron

o 

pushrods and glue them into the slits in the ailerons using
some CA glue.

16. Secure the aileron servo to the location shown using

o 

some foam-safe CA glue.

15

INSTALLING THE MOTOR

AND RADIO GEAR

1. Glue the horizontal and vertical fuselage doublers

o 

to the underside of the horizontal and vertical fuselage
as shown.

3. This is a good time to reinforce the motor mount by

o 

adding some glue around the edges, and to the front of the
ABS motor mount.

4. Locate the 1/8" x 3/64" x 1" [3 x 1 x 24.5mm] flat, carbon

o 

tail skid and glue it into the slit on the underside of the tail,
as shown.

2. Glue the upper horizontal fuselage doubler to either

o 

side of the upper horizontal fuselage as shown.

16

5. Locate the landing gear. Remove the tape holding

o 

them in place and thread them through the vertical
fuselage and into the horizontal fuselage. Be careful,
DO NOT press the landing gear all the way through the
horizontal fuselage. Glue the landing gear in place using
some foam-safe CA glue.

7. Place a small amount of the loop side of the self

o 

adhesive hook and loop material to the back of the ESC and
receiver that will be used.

6. Use a hobby knife to remove the foam that sits behind

o 

the center hole of the motor mount, so that it does not
interfere with the operation of the motor. Install the motor to
the motor mount using the screws provided with the motor,
or using the 3/8" x 5/64" [10 x 2mm] self tapping screws
provided with the Yak.

8. Place the hook portion of the self adhesive hook and

o 

loop material on the Yak at the positions you wish to mount
the receiver, ESC, and battery. One example of where to
position the radio gear is shown above. These components
may be placed anywhere on the fuselage, as long as they do
not interfere with the action of the servos.

9. Install the propeller and propeller adaptor onto

o 

the motor.

17

GET THE MODEL READY TO FLY

FULL

THROTTLE

RUDDER

MOVES

RIGHT

ELEVATOR

MOVES DOWN

RIGHT AILERON

MOVES UP
LEFT AILERON
MOVES DOWN

4-CHANNEL RADIO SETUP

(STANDARD MODE 2)

These are the recommended control surface throws:

ELEVATOR

LOW RATE 3D RATE

1-3/4”

[44mm]

30deg

Up

1-3/4”

[44mm]

30deg

Down

2-3/4”

[70mm]

52deg

Up

2-3/4”

[70mm]

52deg

Down

RUDDER

1-3/4”

[44mm]

20deg

Right

1-3/4”

[44mm]

20deg

Left

4”

[102mm]

53deg

Right

4”

[102mm]

53deg

Left

AILERONS

2”

[51mm]

27deg

Up

2”

[51mm]

27deg

Down

3-1/2”

[89mm]

53deg

Up

3-1/2”

[89mm]

53deg

Down

Check the Control Directions

1. Turn on the transmitter and receiver and center the

o 

servos. Make certain all the servo arm screws are in place.

2. With the transmitter and receiver still on, check all the

o 

control surfaces to see if they are centered. If necessary,
adjust the pushrod lengths to center the control surfaces.

Set the Control Throws

Use a ruler to accurately measure and set the control throw
of each control surface as indicated in the chart that follows.
If your radio does not have dual rates, we recommend setting
the throws at the low rate setting.

NOTE: The throws are measured at the widest part of the
elevators, rudder and ailerons.

3. Make certain that the control surfaces and the electric

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motor respond in the correct direction as shown in the
diagram. If any of the controls respond in the wrong direction,
use the servo reversing in the transmitter to reverse the
servos connected to those controls. Be certain the control
surfaces have remained centered. Adjust if necessary.

Note: It is highly recommended that a computer radio with
exponential be used, if this airplane is to be flown using the
3D control surface throws. Use the exponential function to
lessen the control movement around center without changing

-

the control surface endpoints.
starting value to use for these 3D rates. Feel free to adjust
the 3D throw exponential value to suit your flying style.

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50% is a good exponential

IMPORTANT: The Yak 54 3D Indoor EP ARF has been
extensively flown and tested to arrive at the throws at

which it flies best. Flying your model at these throws will
provide you with the greatest chance for successful first
flights. If, after you have become accustomed to the way
the Yak flies, you would like to change the throws to suit
your taste, that is fine. However, too much control throw
could make the model difficult to control, so remember,
“more is not always better.”

Balance the Model (C.G.)

More than any other factor, the C.G. (balance point)
can have the greatest effect on how a model flies, and
may determine whether or not your first flight will be
successful. If you value this model and wish to enjoy it for
many flights, DO NOT OVERLOOK THIS IMPORTANT
PROCEDURE. A model that is not properly balanced
will be unstable and possibly unflyable.

At this stage the model should be in ready-to-fly condition
with all of the systems in place including the brushless motor,
landing gear, the radio system, and battery pack.

1. A “+” mark has been included on the fuselage, at the

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rear of the servo mounts, as a reference for balancing the
model. The recommended C.G. is located 3/4" [19 mm] in

front of this mark.

2. With all parts of the model installed (ready to fly) lift the

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model upside-down at the balance point you desire.

3. If the tail drops, the model is “tail heavy” and the battery

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pack and/or receiver must be shifted forward or weight must
be added to the nose to balance. If the nose drops, the model
is “nose heavy” and the battery pack and/or receiver must be
shifted aft or weight must be added to the tail to balance. If
possible, relocate the battery pack and receiver to minimize
or eliminate any additional ballast required.

4. IMPORTANT: If you found it necessary to add any

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weight or move components, recheck the C.G. after the
changes have been made

PREFLIGHT

This is where your model should balance for the first
flights. Later, you may wish to experiment by shifting
the C.G. up to 1-1/4" [32 mm] forward of the mark or
back, to the mark, to change the flying characteristics.
Moving the C.G. forward may improve the smoothness
and stability, but the model may then require more speed
for takeoff and make it more difficult to slow for landing.
Moving the C.G. aft makes the model more maneuverable,
but could also cause it to become too difficult to control.
In any case, start at the recommended balance point
and do not at any time balance the model outside the
specified range.

Identify Your Model

No matter if you fly at an AMA sanctioned R/C club site or
if you fly somewhere on your own, you should always have
your name, address, telephone number and AMA number
on or inside your model. It is required at all AMA R/C club
flying sites and AMA sanctioned flying events. Fill out the
identification tag on page 23 (or on the decal sheet) and
place it on or inside your model.

Charge the Batteries

Follow the battery charging instructions that came with your
radio control system to charge the batteries. You should
always charge your transmitter and receiver batteries the night
before you go flying, and at other times as recommended by
the radio manufacturer.

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CAUTION: Unless the instructions that came with your
radio system state differently, the initial charge on new
transmitter and receiver batteries should be done for
15 hours using the slow-charger that came with the
radio system. This will “condition” the batteries so that
the next charge may be done using the fast-charger
of your choice. If the initial charge is done with a fast­charger the batteries may not reach their full capacity
and you may be flying with batteries that are only
partially charged.

MOTOR SAFETY PRECAUTIONS

Failure to follow these safety precautions may

result in severe injury to yourself and others.

Get help from an experienced pilot when learning to
operate motors.

Use safety glasses when starting or running motors.

Balance Propellers

Carefully balance your propeller and spare propellers
before you fly. An unbalanced prop can be the single most
significant cause of vibration that can damage your model.
Not only will motor mounting screws and bolts loosen,
possibly with disastrous effect, but vibration may also
damage your radio receiver and battery.

We use a Top Flite Precision Magnetic Prop Balancer
(TOPQ5700) in the workshop and keep a Great Planes
Fingertip Prop Balancer (GPMQ5000) in our flight box.

Range Check

Ground check the operational range of your radio before
the first flight of the day. With the transmitter antenna
collapsed, or with the power down mode activated, and the
receiver and transmitter on, you should be able to walk at
least 100 feet away from the model and still have control.
Have an assistant stand by your model and, while you work
the controls, tell you what the control surfaces are doing.
Repeat this test with the motor running at various speeds
with an assistant holding the model, using hand signals
to show you what is happening. If the control surfaces do
not respond correctly, do not fly! Find and correct the
problem first. Look for loose servo connections or broken
wires, corroded wires on old servo connectors, poor solder
joints in your battery pack or a defective cell, or a damaged
receiver crystal from a previous crash.

Do not run the motor in an area of loose gravel or sand; the
propeller may throw such material in your face or eyes.

Keep your face and body as well as all spectators away
from the plane of rotation of the propeller as you start and
run the motor.

Keep these items away from the prop: loose clothing, shirt
sleeves, ties, scarves, long hair or loose objects such as
pencils or screwdrivers that may fall out of shirt or jacket
pockets into the prop.

LITHIUM BATTERY HANDLING AND USAGE

WARNING!! Read the entire instruction sheet included

with your battery. Failure to follow all instructions
could cause permanent damage to the battery and its
surroundings, and cause bodily harm!

• ONLY use a LiPo approved charger. NEVER use a

NiCd/NiMH peak charger!

• NEVER charge in excess of 4.20V per cell.

• ONLY charge through the “charge” lead. NEVER

charge through the “discharge” lead.

• NEVER charge at currents greater than 1C.

• ALWAYS set charger’s output volts to match battery

volts.

• ALWAYS charge in a fireproof location.

• NEVER trickle charge.

• NEVER allow the battery temperature to exceed

150° F (65° C).

• NEVER disassemble or modify pack wiring in any

way or puncture cells.

• NEVER discharge below 2.5V per cell.

• NEVER place on combustible materials or leave

unattended during charge or discharge.

• ALWAYS KEEP OUT OF REACH OF CHILDREN.

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AMA SAFETY CODE (ExCERPTS)

CHECK LIST

Read and abide by the following excerpts from the Academy
of Model Aeronautics Safety Code. For the complete Safety
Code refer to Model Aviation magazine, the AMA web site or
the Code that came with your AMA license.

General

1) I will not fly my model aircraft in sanctioned events,
air shows, or model flying demonstrations until it has
been proven to be airworthy by having been previously,
successfully flight tested.

2) I will not fly my model aircraft higher than approximately
400 feet within 3 miles of an airport without notifying the
airport operator. I will give right-of-way and avoid flying in the
proximity of full-scale aircraft. Where necessary, an observer
shall be utilized to supervise flying to avoid having models fly
in the proximity of full-scale aircraft.

3) Where established, I will abide by the safety rules for the
flying site I use, and I will not willfully and deliberately fly my
models in a careless, reckless and/or dangerous manner.

5) I will not fly my model unless it is identified with my name
and address or AMA number, on or in the model. Note: This
does not apply to models while being flown indoors.

7) I will not operate models with pyrotechnics (any device
that explodes, burns, or propels a projectile of any kind).

Radio Control

1) I will have completed a successful radio equipment ground
check before the first flight of a new or repaired model.

2) I will not fly my model aircraft in the presence of spectators
until I become a qualified flier, unless assisted by an
experienced helper.

3) At all flying sites a straight or curved line(s) must be
established in front of which all flying takes place with the
other side for spectators. Only personnel involved with flying
the aircraft are allowed at or in the front of the flight line.
Intentional flying behind the flight line is prohibited.

4) I will operate my model using only radio control
frequencies currently allowed by the Federal
Communications Commission.

5) I will not knowingly operate my model within three

miles of any pre-existing flying site except in accordance
with the frequency sharing agreement listed [in the

complete AMA Safety Code].

9) Under no circumstances may a pilot or other person
touch a powered model in flight; nor should any part of the

model other than the landing gear, intentionally touch
the ground, except while landing.

During the last few moments of preparation your mind
may be elsewhere anticipating the excitement of the first
flight. Because of this, you may be more likely to overlook
certain checks and procedures that should be performed
before the model is flown. To help avoid this, a check list
is provided to make sure these important areas are not
overlooked. Many are covered in the instruction manual,
so where appropriate, refer to the manual for complete
instructions. Be sure to check the items off as they are
completed (that’s why it’s called a check list!).

1. Check the C.G. according to the measurements

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provided in the manual.

2. Be certain the battery and receiver are securely

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mounted in the fuse. Simply stuffing them into place with
foam rubber is not sufficient.

3. Extend your receiver antenna.

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4. Add a drop of oil to the axles so the wheels will

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turn freely.

5. Make sure all hinges are securely in place.

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6. Confirm that all controls operate in the correct direction

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and the throws are set up according to the manual.

7. Make sure that all servo arms are secured to the servos

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with the screws included with your radio.

8. Make sure any wires you may have used do not interfere

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with other systems (servo arms, pushrods, etc.).

9. Balance your propeller (and spare propellers).

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10. Place your name, address, AMA number and

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telephone number on your model.

11. If you wish to photograph your model, do so before

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your first flight.

12. Range check your radio when you get to the

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flying field.

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F LYI N G

The Yak 54 3D Indoor EP ARF is an airplane suitable for
both indoor and outdoor flying. If you plan on flying outdoors,
make sure that you choose days with very light to calm winds
(gusting to less than 5 mph). If this is your first experience with
an indoor-style foamie, seek help from experienced modelers.
Join a local flying club or ask your local hobby dealer where
the nearest approved flying sites are in your area.

CAUTION (THIS APPLIES TO ALL R/C AIRPLANES): If,
while flying, you notice an alarming or unusual sound such
as a low-pitched “buzz,” this may indicate control surface
flutter. Flutter occurs when a control surface (such as an
aileron or elevator) or a flying surface (such as a wing or
stab) rapidly vibrates up and down (thus causing the noise).
In extreme cases, if not detected immediately, flutter can
actually cause the control surface to detach or the flying
surface to fail, thus causing loss of control followed by
an impending crash. The best thing to do when flutter is
detected is to slow the model immediately by reducing
power, then land as soon as safely possible. Identify which
surface fluttered (so the problem may be resolved). Make
certain all pushrod linkages are secure and free of play. If it
fluttered once, under similar circumstances it will probably
flutter again unless the problem is fixed. Some things
which can cause flutter are; Not mounting control horns
solidly; Excessive free play in servo gears; Insecure servo
mounting; and one of the most prevalent causes of flutter;
Flying the model at excessive speeds.

you land. Fly around for a bit and try a few simple maneuvers
like: slow flight, gentle rolls, loops, stalls, and hammerhead
stalls. Practice a few landing approaches.

Landing

Before you land, throttle down completely (with a safe
amount of altitude). You’ll notice that when you power off,
the airplane will lose speed very quickly but will not pitch
down. To keep your speed up you’ll have to pitch down rather
steeply and this can be less than ideal for most landings. Set
up for landing by throttling down to an “idle” instead. If you
find it difficult to get the right setting, power-off completely
and try blipping the throttle. For a short approach, power-off
completely while at altitude and pitch down. At the flare, be
ready to blip the throttle for a gentle 3-point landing.

One final note about flying your model: Have a goal or flight
plan in mind for every flight. This can be learning a new
maneuver(s), improving a maneuver(s) you already know,
or learning how the model behaves in certain conditions
(such as on high or low rates). This is not necessarily to
improve your skills (though it is never a bad idea!), but more
importantly so you do not surprise yourself by impulsively
attempting a maneuver and suddenly finding that you’ve
run out of time, altitude or airspeed. Every maneuver should
be deliberate, not impulsive. A flight plan greatly reduces
the chances of crashing your model just because of poor
planning and impulsive moves. Remember to think.

Have a ball! But always stay in control

and fly in a safe manner.

Takeoff

The Yak 54 3D Indoor EP ARF can take off from the ground
(ROG) or can be hand launched. Rise-off-ground (ROG)
takeoffs should be reserved for indoor flying and should
be performed with the model rolling away from you and
others. For your first flight it’s probably a good idea to have
an assistant hand-launch the plane for you. You should be
ready to correct (or fly through) any trim errors. First, set
your transmitter for LOW RATES. Launch your plane directly
into the wind (and away from others). After your assistant
launches the plane, have him come back and adjust the trim
on your transmitter. If you want to perform an ROG takeoff,
make sure the surface you’re using is completely smooth
and free from “potholes” that can flip the plane or break the
landing gear.

Flight

When you’re airborne and your plane is trimmed out,
throttle back and fly the pattern. Get used to the way the
model handles with standard control inputs. Based on your
preference, you may want to adjust your rates or exponential
settings in your radio. If your assistant is still available, have
him take notes for you so you can make adjustments when

GOOD LUCK AND GREAT FLYING!

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