Seagull Models Mehari Aerobatics CEA-309 User manual

“Graphics and specifications may change without notice”.
MS:167
ASSEMBLY MANUAL
Specifications:
Wingspan------------------------------66.9in(170cm).
Wingarea-----------------764.2sq.in(49.3sqdm).
Weight------------------------10.6lbs(4.8kg).
Length------------------------------58.7in(149.0cm).
Engine ------------------0.91-1.2cu.in----2-4-stroke.
Radio-------------------4channelswith6 servos.
Electricconversion:optional

CEA-309 MEHARI AEROBATICS.Instruction Manual.
2
INTRODUCTION.
Thank you for choosing the CEA-309 MEHARI AEROBATICS ARTF by SEAGULL MODELS
COMPANY LTD. The CEA-309 MEHARI AEROBATICS was designed with the intermediate/
advanced sport flyer in mind. It is a semi scale airplane which is easy to fly and quick to assemble.
Theairframeisconventionallybuiltusingbalsa,plywoodtomakeitstrongerthantheaverageARTF
,yetthedesignallowstheaeroplanetobekeptlight.Youwillfindthatmostoftheworkhasbeendone
foryou already.Themotor mounthas beenfitted andthe hingesare pre-installed. Flyingthe CEA-
309 MEHARI AEROBATICS is simply a joy.
This instruction manual is designed to help you build a great flying aeroplane. Please read this
manual thoroughly before starting assembly of your CEA-309 MEHARI AEROBATICS . Use the
parts listing below to identify all parts.
WARNING.
Please be aware that this aeroplane is not a toy and if assembled or used incorrectly it is
capable of causing injury to people or property. WHEN YOU FLY THIS AEROPLANE YOU
ASSUME ALL RISK & RESPONSIBILITY.
IfyouareinexperiencedwithbasicR/CflightwestronglyrecommendyoucontactyourR/Csupplier
and join your local R/C Model Flying Club. R/C Model Flying Clubs offer a variety of training
proceduresdesignedtohelpthenewpilotonhisway to successful R/Cflight. Theywill alsobeable
to advise on any insurance and safety regulations that may apply.
KIT CONTENTS
3
1
2
2
4
3
58
6

3
www.seagullmodels.com
ADDITIONAL ITEMS REQUIRED.
0.91 - 1.2 2-4--stroke.
Engine 20cc-22cc.
Computer radio with 6 servos.
Glow plug to suit engine.
Propeller to suit engine.
Protective foam rubber for radio
system.
Siliconefuel line.
TOOLS & SUPPLIES NEEDED.
Thick cyanoacrylate glue.
30 minute epoxy.
5 minute epoxy.
Hand or electric drill.
Assorted drill bits.
Modellingknife.
Straight edge ruler.
2mm ball driver.
Phillips head screwdriver.
220 grit sandpaper.
90° square or builder’s triangle.
Wire cutters.
Masking tape & T-pins.
Thread-lock.
Paper towels.
KIT CONTENTS.TS
The control surfaces, including the
ailerons, elevators, and rudder, are
prehinged with hinges installed, but
the hinges are not glued in place. It
is imperative that you properly
adhere the hinges in place per the
steps that follow using a high-quality
thin C/A glue.
2)Removeeach hingefromthewing panel
and aileron and place a T-pin in the center of
each hinge. Slide each hinge into the aileron
untiltheT-pin issnug againstthe aileron.This
will help ensure an equal amount of hinge is
oneithersideofthehingeline when theaileron
is mounted to the wing panel.
Note:
1) Carefully remove the aileron from one
of the wing panels. Note the position of the
hinges.
HINGING THEAILERON .
3) Slide the aileron on the wing panel until
there is only a slight gap. The hinge is now
centered on the wing panel and aileron.
Remove the T-pins and snug the aileron
against the wing panel.A gap of 1/64” or less
shouldbe maintainedbetween the wingpanel
andaileron.
Hinge.
T-pin.
1 Fuselage
2 Wing Set
3 Tail Set
4 Cowling
5 Main Landing Gear
6 Wing Tube
7 Hardware Set
8 Fiberglass Wheel Pants

CEA-309 MEHARI AEROBATICS.Instruction Manual.
4
8)Afterbothailerons are securelyhinged,
firmly grasp the wing panel and aileron to
make sure the hinges are securely glued and
cannot be pulled out. Do this by carefully
applying medium pressure, trying to separate
the aileron from the wing panel. Use caution
not to crush the wing structure.
Worktheaileron up and down several
times to “work in” the hinges and
check for proper movement.
Note:
HINGING THE ELEVATOR.
Glue the rudder hinges in place using the
same techniques used to hinge the ailerons.
4) Deflect the aileron and completely
saturate each hinge with thin C/A glue. The
aileronsfrontsurface should lightlycontactthe
wing during this procedure. Ideally, when the
hinges are glued in place, a 1/64” gap or less
will be maintained throughout the lengh of the
aileron to the wing panel hinge line.
Thehingeis constructed of a special
material that allows the C/A to wick
or penetrate and distribute
throughout the hinge, securely
bonding it to the wood structure of
the wing panel and aileron.
Note:
Hinge.
C/Aglue.
6) Using C/A remover/debonder and a
papertowel, remove anyexcess C/Agluethat
may have accumulated on the wing or in the
aileronhinge area.
5)Turnthe wingpanel overand deflectthe
aileron in the opposite direction from the
opposite side. Apply thin C/A glue to each
hinge,makingsurethattheC/Apenetratesinto
both the aileron and wing panel.
7) Repeat this process with the other wing
panel, securely hinging the aileron in place.

5
www.seagullmodels.com
Aileroncontrol horn.
INSTALL THE AILERONS CONTROL
HORN.
1) Locate the hardware necessary to install
the control horns for the ailerons.
HINGING THE RUDDER.
Glue the rudder hinges in place using the
same techniques used to hinge the ailerons.
Hinge.
Fiberglass control horn.
2)Position the Control horn on the Aileron
and use 30-minute Epoxy
Elevator control horn.
Install the elevator control horn using the
same method as same as the aileron control
horns.
INSTALL ELEVATOR CONTROL HORN.
Fiberglass control horn.
Position the Control horn on the Aileron and
use 30-minute Epoxy
INSTALL RUDDER CONTROL HORN.
Repeatsteps toinstall the rudder control horn
as same as steps done for ailerons.
Fiberglass control horn.
Epoxy.
Epoxy.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
6
Thread locker glue.
1) Using a modeling knife, carefully cut
off the rear portion of one of the 3 nylon tubes
leaving 1/2” protruding from the rear of the
stopper. This will be the fuel pick up tube.
INSTALLING THE STOPPER ASSEMBLY.
2) Usinga modelingknife, cutone length
ofsilicon fuel line. Connectone endofthe line
tothe weightedfuel pickup and theother end
to the nylon pick up tube.
ENGINE MOUNT INSTALLATION.
Ruddercontrolhorn.
1) Locate the items necessary to install the
engine mount included with your model. .
2) Usefour4x30mm headboltsandfour 4mm
washers to attach the engine mount rails to
thefirewall. Tighten the screws .Make sure to
use threadlock on the screws to help prevent
them from vibrating loose.
4x30mm.
Epoxy.

7
www.seagullmodels.com
5) With the stopper assembly in place,
the weighted pick-up should rest away from
therear of thetank and movefreely inside the
tank. The top of the vent tube should rest just
below the top of the tank. It should not touch
the top of the tank.
6) When satisfied with the alignment of
the stopper assembly tighten the 3 x 20mm
machine screw until the rubber stopper ex-
pands and seals the tank opening. Do not
overtighten the assembly as this could cause
the tank to split.
Venttube. Fuel pick up tube.
Fuel fill tube.
3) Carefully bend the second nylon tube
up at a 45º angle. This tube is the vent tube.
4) Test fit the stopper assembly into the
tank. It may be necessary to remove some of
the flashing around the tank opening using a
modeling knife. If flashing is present, make
sure none falls into the tank.
You should mark which tube is the vent
and which is the fuel pickup when you attach
fuel tubing to the tubes in the stopper. Once
thetank isinstalled insidethe fuselage,it may
be difficult to determine which is which.
FUEL TANK INSTALLATION.
 7) Slide the fuel tank into the fuselage. Guide
the lines from the tank through the hole in the
firewall.
Fueltank.
 8) Use plywood template to hold in place
the fuel tank with C/A glue to secure the fuel
tank inside the fuselage.
Venttube.
Fuel pick up tube.
Fuel fill tube.
9) Connect the lines from the tank to the engine
and muffler. The vent line will connect to the
muffler and the line from the clunk to the
carburetor.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
8
AdjustableServo
connector.
Servoarm.
Loctite secure.
1PCS.
Throttleservoarm.Elevatorservoarm.
Rudderservoarm.
3/32” Hole.
INSTALLING THE SWITCH.
Installthe switch intothe precutholein the
side, in the fuselage.
Switch.
Trimand cut.
Blow through one of the lines to en-
sure the fuel lines have not become kinked
inside the fuel tank compartment. Air
should flow through easily.
INSTALLING THE FUSELAGE SERVOS.
Throttle servo.
Elevator servo.
Rudder servo.
1) Installthe rubbergrommets andbrass
colletsonto thethrottleservo. Testfitthe servo
into the aileron servo mount.
 2) Secure the servos with the screws pro-
vided with your radio system.
Because the size of servos differ, you
mayneedtoadjust the sizeoftheprecutopen-
ing in the mount. The notch in the sides of the
mount allow the servo lead to pass through.
THROTTLE SERVO ARM INSTALLATION.
Install adjustableservoconnectorinthe servo
arm as same as picture below:

9
www.seagullmodels.com
2) Use a pin drill and 4mm drill bit to drill a
small indentation in the mount for the engine
mounting screw.
3) Use a drill to drill the four holes in the engine
mount rails.
4) On the fire wall has the location for the
throttle pusshrod tube (pre-drill).
4.5mm.
4mm.
145mm.
MOUNTING THE ENGINE.
 1) Positiontheenginewiththedrivewasher
(145mm) forward of the firewall as shown.
8) Reinstall the servo horn by sliding the
connector over the pushrod wire. Center the
throttle stick and trim and install the servo horn
perpendicular to the servo center line.
Machinescrew M4x30mm.
Pushrodwire.
7) Slide the throttle pushrod wire into the tube.
Position the engine between the mounts. Use
four M4x30mm machine screws to secure the
engine to the mount as shown.
5) Slide the pushrod tube in the firewall and
guide it through the fuel tank mount. Use
medium C/A to glue the tube to the firewall and
the fuel tank mount.
6) Connect the Z-bend in the 450mm throttle
pushrod to the outer hole of the carburetor arm.
Pushrod tube hole.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
10
9) Move the throttle stick to the closed position
and move the carburetor to closed. Use a 2.5mm
hex wrench to tighten the screw that secures
the throttle pushrod wire. Make sure to use
threadlock on the screw so it does not vibrate
loose.
1) Locate the items neccessary to install
thewheel andwheel pants tothe landinggear
as shown.
WHEEL AND WHEEL PANTS
INSTALLATION.
wheel collar.
wheel.
Axle.
Washer. M3.
wheel Pant.
wheel.
M3.
M3.
wheel collar.
nut. Axle.
Washer.
M3.
4) Slidethecollar totheaxle andsetscrew
the collars to secure the collar to the axle and
thenslider the wheelon theaxle with adrop of
oilontheaxle so the wheelwillspinfreelywhen
installed. Prepare a second collar and tighten
the setscrew using hex wrench to secure the
collar to the axle.
5) Place the wheel assembly in the wheel
pants. The threaded portion of the axle will fit
the notch of the wheel pant as shown.
3) You have to trim each axle using a tool
cutting and cut-off wheel.
Caution when cutting the axles and
wear protective goggles.
2) Follow diagram below for wheel pant
installation:Use a drill and 8mm drill bit to drill
a hole in the wheel pants.
C/Aglue.

11
www.seagullmodels.com
6) Slide the threaded end of the axle
through the hole in the bottom of the landing
gear leg. Use a washer and locknut to tighten
the axle to the landing gear. Make sure to use
threadlock on the nut so it won’t vibrate loose
in flight as shown.
C/Aglue.
LandingGear. wheel Pant.
Lockerglue.
 7) Tighten the setcrews using a hex
wrench to secure the collars on the axle over
the flat spot to retain the wheel as shown.
Repeat steps as above to attach remain-
ing wheel pants to the landing gear.
INSTALLING THE MAIN LANDING GEAR
TO FUSELAGE.
 8) The blind nuts for securing the landing
gearare already mountedinside thefuselage.
 9) Using the hardware provided, mount
the main landing gear to the fuselage.
 10) Place the fuselage inverted on the
workbenchin a suitablestand. Setthe landing
gear in place and use a screwdrive to secure
the landing gear to the fuselage using bolts
M4x20mmandwashers. Makesuretouse the
threadlock on the bolts so they don’t vibrate
loose.
Thread locker glue.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
12
Machine screw M3x10mm.
Needlevalve.
 3) Installthemuffler andmuffler extension
onto the engine and make the cutout in the
cowl for muffler clearance. Connect the fuel
and pressure lines to the carburetor, muffler
and fuel filler valve. Secure the cowl to fuse-
lage using the M3x10mm screws.
2) While keeping the back edge of the
cowl flush with the marks, align the front of
thecowlwiththecrankshaft of theengine. The
front of the cowl should be positioned so the
crankshaft is in nearly the middle of the cowl
opening.Usethespinnerbackplateasaguide.
Hold the cowl firmly in place using pieces of
masking tape.
Becauseof the sizeof thecowl, it maybe nec-
essaryto usea needlevalve extensionfor the
highspeed needle valve. Makethisout ofsuf-
ficient length 1.5mm wire and install it into the
end of the needle valve. Secure the wire in
placeby tighteningthe setscrew in the side of
the needle valve.
Trim and cut.
Trim and cut.
COWLING.
Trim and cut.
1)Slidethefiberglass cowloverthe engine
and line up the back edge of the cowl with the
marksyoumade on thefuselagethen trimand
cut as shown.

13
www.seagullmodels.com
ELECTRIC POWER CONVERSION.
1) Locate the items neccessary to install the
electric power conversion included with your
model.
2) Attach the electric motor box to the firewall
suitable with the cross lines drawn on the electric
motor box and firewall. Using epoxy and balsa
stick to secure the motor box to the firewall.
Please see pictures below.
- Model size: .75-91 size models
- Motor: 50mm 310 rev per volt
- Propeller: 14x10 ~ 15x8
- ESC: 60A
- Lipo Batteries: 8 cell 3200mA
Recommendation EP parts as shown (not
included with your model)
4mm.
4mm.
3) Attach the motor to the front of the electric
motor box using four 3mm blind nut, four
M3x15mm hex head bolts to secure the motor.
Please see picture shown.
M4x20mm.
Blindnut.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
14
INSTALLING THE SPINNER.
Battery.
Speed control.
5) Attach the speed control to the side of the
motor box using two-sided tape and tie wraps.
Connect the appropriate leads from the speed
control to the motor. Make sure the leads will
not interfere with the operation of the motor.
Install the spinner backplate, propeller and
spinner cone.
The propeller should not touch any part
of the spinner cone. If it does, use a
sharp modeling knife and carefully trim away
the spinner cone where the propeller comes
in contact with it.
Balsa stick.
Electric motor.
Epoxy.
140mm.
Epoxy.
M3x15mm.

15
www.seagullmodels.com
INSTALLING THEAILERON - FLAPSERVOS.
Servos. Smallweight.
Thread.
1) Usinga smallweight (Weightedfuel pick-up
workswell)and string, feedthestring through
the wing as indicated.
Because the size of servos differ, you
mayneedtoadjustthesizeoftheprecutopen-
ing in the mount. The notch in the sides of
themountallowtheservoleadtopassthrough.
String.
Small weight.
2) Place the servo between the mounting
blocksandspaceitfromthehatch.Use a pencil
to mark the mounting hole locations on the
blocks.
3) Use drill bit in a pin vise to drill the mouting
holes in the blocks.
4) Apply 2-3 drops of thin C/A to each of the
mounting holes. Allow the C/A to cure without
using accelerator.
6) Secure the servo to the aileron hatch using
Phillips screwdriver and the screws provided
with the servo.
5) Use dental floss to secure the connection
so they cannot become unplugged.
7) Apply 1-2 drops of thin C/A to each of the
mounting tabs. Allow the C/A to cure without
using accelerator.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
16
9) Set the aileron hatch in place and use a
Phillips screw driver to install it with four wood
screws.
8) A string has been provided in the wing to
pull the aileron lead through to the wing root.
Remove the string from the wing at the servo
location and use the tape to attach it to the
servoextension lead. Pullthe leadthroughthe
wing and remove the string.

17
www.seagullmodels.com
Wing. M3lock nut.
M3 lock nut.
M3clevis.
60mm.
100mm.
Aileron.
AILERONPUSHROD HORN INSTALLATION
Flap.
Flap.
Wing.Wing.
Repeat the procedure for the other aileron servo.
Cut.
 3) Slide the stabilizer into place in the pre-
cut slot in the rear of the fuselage. The stabi-
lizer should be pushed firmly against the front
of the slot.
INSTALLING THE HORIZONTALSTABILIZER.
1) Using a ruler and a pen, locate the
centerlineofthehorizontalstabilizer,atthetrail-
ing edge, and place a mark. Use a triangle
and extend this mark, from back to front,
across the top of the stabilizer. Also extend
thismark downthe backof thetrailing edgeof
the stabilizer.
Draw center line.
2)Usingamodelingknife,carefullyremove
thecovering at mountingslot of horizontalsta-
bilizer ( both side of fuselage).

CEA-309 MEHARI AEROBATICS.Instruction Manual.
18
INSTALLING VERITICAL FIN.
Whencuttingthrough thecoveringto re-
move it, cut with only enough pressure
toonly cut through the coveringitself. Cutting
into the balsa structure may weaken it.
Pen.
Epoxy.
Trimand cut.
 5) Remove thestabilizer. Using thelines
youjust drewas aguide, carefullyremove the
covering from between them using a model-
ingknife.
 6) Using a modeling knife, carefully re-
move the covering that overlaps the stabilizer
mounting platform sides in the fuselage. Re-
move the covering from both the top and the
bottom of the platform sides.
 7) When you are sure that everything is
aligned correctly, mix up a generous amount
of 30 Minute Epoxy. Apply a thin layer to the
topand bottomof the stabilizermounting area
and to the stabilizer mounting platform sides
in the fuselage. Slide the stabilizer in place
and realign. Double check all of your mea-
surementsonce more beforethe epoxy cures.
Holdthestabilizerinplace withT-pinsor mask-
ing tape and remove any excess epoxy using
a paper towel and rubbing alcohol.
1) Using a modeling knife, remove the
covering from over the precut hinge slot cut
into the lower rear portion of the fuselage.
Remove covering.
 4) With the stabilizer held firmly in place,
use a pen and draw lines onto the stabilizer
where it and the fuselage sides meet. Do this
on both the right and left sides and top and
bottom of the stabilizer.
Fill epoxy.
Fill epoxy.

19
www.seagullmodels.com
Elevator control horn.
Fill epoxy.
90º
Vertical
Stabilizer.
Horizontal
Stabilizer.
Epoxy.
3) Slide the vertical stabilizer back in
place. Using a triangle, check to ensure that
thevertical stabilizeris aligned90º tothe hori-
zontal stabilizer.
ELEVATOR - RUDDER PUSHROD HORN
INSTALLATION.
 1) Install the elevator control horn using
the same method as with the aileron control
horns.
 2) Position the elevator control horn on
the both side of elevator.
Fill epoxy.
2) While holding the vertical stabilizer
firmly in place, use a pen and draw a line on
each side of the vertical stabilizer where it
meets the top of the fuselage.
4) When you are sure that everything is
alignedcorrectly,mixupa generous amountof
Flash30 MinuteEpoxy. Applyathinlayertothe
mounting slot and to bottom of the vertical sta-
bilizer mounting area. Apply epoxy to the bot-
tomand topedges ofthe fillerblockand tothe
lower hinge also. Set the stabilizer in place
andrealign. Doublecheckallofyourmeasure-
mentsoncemorebeforetheepoxycures.Hold
the stabilizer in place with T-pins or masking
tape and remove any excess epoxy using a
papertoweland rubbing alcohol. Allowthe ep-
oxy to fully cure before proceeding.
Rudder control horn.
Elevator control horn.
Hinge.
Epoxy.

CEA-309 MEHARI AEROBATICS.Instruction Manual.
20
M2 lock nut.
M2clevis.
580mm.
620mm. Elevator pushrod.
A.
C/Aglue.
 4) Elevatorandrudderpushrodsassembly
as pictures below.
 3) Thread one clevis and M3 lock nut on
toeachelevator controlrod. Threadthe horns
onuntil they areflush with theends ofthecon-
trol rods.
Rudder pushrod.
A.
C/Aglue.
Elevator pushrod.
MOUNTING THE TALI WHEEL.
1) Locate the items for this section of the
manual.
Control horn.
M2lock nut.
Metalclevis.
Elevator pushrod.
Control horn.
M2lock nut.
Rudder pushrod.
Elevator pushrod.
M2 lock nut.
M2clevis.
580mm.
620mm.
Elevator pushrod.
Rudder pushrod.
2 pcs.
1 pcs.
A.