Avantco Aurora Ultimate 90 User manual

2AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
AVANT Aurora Ultimate 90
Assembly Manual V2.00
LIABILITY DISCLAIMER
This kit is for a radio controlled (RC) helicopter. RC Helicopters are not
toys. Moving parts can present a hazard to operators, bystanders and
anyone or anything that could be reached by the RC helicopter. Improper
operation, maintenance or assembly can potentially cause a helicopter to
pose a danger to persons or objects including but not limited to the
possibility of causing serious physical injury and even death. This product
is intended to be used by experienced adult radio control helicopter pilots
under controlled safety conditions and on locations properly authorized
and setup for safe flying and away from other people. Under no
circumstance should a minor be allowed to operate this or any radio
controlled helicopter without the approval, supervision and direction of his
parent or legal guardian who takes full responsibility for the minor's
actions. Do not operate an RC helicopter within the vicinity of homes,
trees, electrical lines during inclement weather or rain or near crowds of
people. After leaving its facilities the manufacturer has no way of
maintaining control or supervision over the assembly and/or operation of
the helicopter.
The manufacturer and/or its agents assume no responsibility or liability
whatsoever for any damages including but not limited to ones generated
by incidental or consequential damages.
The operator of the helicopter assumes all responsibility and liability that
could be result from the correct or incorrect operation of the helicopter.
Symbols:
Important, Correct, Incorrect, Danger, Allow it to set for some time before
continuing

AVANT Aurora Ultimate 90 Assembly Manual _3
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Before you start assembling:
Get the latest manual: It’s highly recommended that you get the latest version of the
manual. Please download a copy by clicking here and use that copy instead of this one.
Important: Using a piece of #400 sanding paper sand the edges of the carbon fiber pieces
that will be close to any electronic wires or fuel tubing. Sharp edges can cut into the electric
wires and since carbon fiber is conductive it can possibly create an electrical shortcut. Sharp
edges can also cut fuel tubing creating leaks that could make the engine operation fail.
Whenever you’re ready to install a carbon fiber piece that will be close to servo wiring make
sure to sand its edges to prevent wire chafing and a possible electrical short circuit.
Bag #1: Left Frame assembly, Motor Mount Center and Gyro Mount.
M3x8 (1) AV00-100-421
M3 Locknut (2) AV00-100-320
M3 Locknut (2) AV00-100-320
A
V00-200-624 (Long)
M3x8 (2)
AV00-100-421
M3x8 (1) AV00-100-421
Install the back sacrificial breakout tab
Install the front canopy mount
AV00-200-511
AV00-200-511 Sacrificial Breakout Tab
AV00-200-262
A
V00-200-625 (Short)
M3x8 (2)
AV00-100-421

4AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
stubs and two 5mm long grommets
AV00-100-604
A
V00-200-504
Install five 26mm spacers
M3x8 (3) AV00-100-421
M3x8 (1) AV00-100-421
AV00-100-604
AV00-100-604
M3x8 (2) AV00-100-421
A
V00-200-744
M3x8 (2)
M3x8 (2) AV00-100-421
A
V00-100-683
Cut the rubber strip into ten 10mm long.
You will use half of them on the left frame
and the other half on the right frame. Using
CA glue install the tank rubber mounts
Not used
Not used
Three holes are marked “Not Used”. The
two closer to the M4 holes are for Muffler
posts like the legacy Hatori muffler posts.
The top one marked “Not Used” is for the
EFX fan shroud and not used in the Aurora.

AVANT Aurora Ultimate 90 Assembly Manual _5
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Using two M3x8 screws install the
Gyro mount plate. Do not use blue
Loctite yet because they will be
loosened later during the installation
of the boom clamp.
Bag #2: Main Gear assembly, Main shaft installation and Left side frame stiffener
M3x8 (2) AV00-100-421
AV00-100-609
M2.5x8 (6) AV00-100-410
M2.5 washer (6) AV00-100-301
Using six M2.5x8 screws
install the Main gear onto the
pre-assembled main gear
hub
Using six M3x6 button head screws
install the constant drive gear onto
the constant drive hub.
M3x6 Button Head (6) AV00-100-441
AV00-200-737 AV00-200-738
AV00-200-678
AV00-200-291
AV00-200-669 NOTE:
Previous version
used flat head
screws instead
of button head.

6AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Install the constant drive gear onto the constant drive gear hub.
Slide the main sleeve into the one-way sprag clutch with the key
coinciding with the key slots and then slide the constant gear hub
into the protruding main sleeve bottom.
Slide the Main Shaft into the main gear
assembly and install the hardened pin
that locks the constant drive hub into the
main shaft and screw the M6x10
setscrew into the bottom of the main
shaft to secure the pin in place, There is
no need to over tighten this setscrew.
Slide the top bearing blocks and the
bottom bearing block oriented as
indicated by the small notched facing the
back. Notice that the small notches for
the entire bearing block should be facing
the rear side of the heli.
AV00-200-676 (Sharp edge should point toward the sleeve)
AV00-200-671
AV00-100-333
Main shaft pin
AV00-100-613
Small notch
faces back
M6x10mm AV00-100-355 Main
shaft pin retainer setscrew
Open bearing side
faces up
Open bearing side
faces down
Open bearing side
faces up
Small notch faces
back
IMPORTANT
NOTE: Pay attention
to the orientation of
the bearing blocks.
The top block open
bearing side should
face up, the mid one
should face down and
the bottom one
should face up.
AV00-200-680
AV00-100-613
VERY IMPORTANT NOTE:
Use Blue or Red Loctite on the mainshaft
pin itself. This will prevent it from sliding
out even if the setscrew becomes lose.
Do not over tighten the M6 setscrew.

AVANT Aurora Ultimate 90 Assembly Manual _7
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
For the next step hold pressure on the main
shaft's middle and bottom bearing blocks
against each other while tightening the
bearing block's bolts shown on the next
illustration. No play should be allowed in
between the blocks and the main sleeve.
This is the main means of holding the main
shaft in place so no play should be allowed.
M3x8 (3)
AV00-100-421
M3x25 (1) AV00-100-427
M3x20 (2) AV00-100-426
AV00-100-612
AV00-100-611
AV00-100-610
AV00-200-509 M3x25 (2) M3x20 (2)
Proceed now to install the side stiffener plate
by using the spacers and screws provided.
While holding the pressure described
above install the M3x8 screws that hold
the top and mid bearing blocks in place.
Notice that one of the M3x8 screws
is a button (round) head screw.
M3x8 (1) Button (Round)
Head AV00-100-442

8AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Bag #3: Clutch Stack, Clutch Bell assembly.
AV00-200-506 Ratio plate
M3x6 (2) AV00-100-420
AV00-200-619
AV00-200-604
AV00-200-606
AV00-100-613
AV00-200-605
AV00-200-309
AV00-200-609
AV00-200-602
M4x4 (1)
AV00-100-351
AV00-200-472
M3x10 (4) AV00-100-422
Install the gear ratio plate making sure that
the notch points toward the back of the helicopter.
Install the assembly on the left frame using the
supplied M3x10 screws to bolt the two bearing blocks.
Don’t tighten them now wait until the engine is
installed to let the starter shaft fit in the clutch first.
Glue the Clutch liner to the Clutch Bell using 30-minute
epoxy making sure to trim the length of the liner strip to
match the bell precisely. You can use masking tape around
the clutch and use it as a plug to push the liner against the
bell wall while it’s curing. Assemble the clutch bell stack as
shown on the left.
Use Red Loctite to lock the pinion into the
inner race of the pinion’s bearing block. Use
Blue Loctite
to secure the
p
inion nut into the
bearing side
faces up
bearing side
faces down

AVANT Aurora Ultimate 90 Assembly Manual _9
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Bag #4: Tail Pickup gear mechanism and gear meshing method.
Assemble the vertical pickup shaft as shown on the left. The roll pin
(black one) is the one above and the dowel pin (silver one) is the one at
the bottom side.
Install the two assemblies into the frame as
shown. Don't tighten the collar or the 2.5mm
dog-bone pin and setscrew until they are
placed in the frames and the mesh is
checked for no play at all and flush
alignment of the inner face of the teeth on
both gears.
You need to replace the 6mm id bearing spacers until
there is no play between the bevel gears. Follow the
instructions shown in the next pages for the gear mesh.
AV00-200-619
AV00-200-618
AV00-200-721
AV00-100-331
AV00-100-330 AV00-200-726
6mm Shim
M3x4 (1)
AV00-100-350
AV00-200-619 (2)
6mm Shim
M3x4 (1)
AV00-100-350
M3x4 (1)
AV00-200-608
A
V00-100-332
M3x8 (8) AV00-100-421
AV00-200-307 - 6mm ID x 0.1mm Shim
AV00-200-308 - 6mm ID x 0.2mm Shim
AV00-200-309 - 6mm ID x 0.3mm Shim
Assemble the torque input shaft
assembly as shown. The spacing
between the blocks is set by the
holes in the frames.

10 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
VERY IMPORTANT!!!
READ AND FOLLOW THE TAIL GEAR MESH METHOD
Failure to do so can cause the tail gears to fail in flight
This is the method used to do a correct mesh on the Aurora tail gears. This applies to both
the front set (the set inside the frames) and the back set (the set inside the tailcase). The
Aurora has a large window to inspect the gears inside the frames as well as the ones inside
the tailcase.
Frame inspection window. Tailcase inspection window.
There are three things that need to be assured for a correct mesh in the Aurora: Flush
alignment, No Play and Lubrication.
1) Flush alignment: Make sure that the gears are aligned so that the inner side of the teeth
are in the same plane flush to each other at the point of contact.
2) No Play: Make sure there is no play between the gears.
3) Lubrication: Make sure to lubricate the gears with a few drops of fuel before each flying
day letting the alcohol evaporate leaving the fuel's oil as lubricant.
1) Flush Alignment:
In order to illustrate how to achieve it here's a couple of pictures of gears aligned incorrectly
followed by a couple of pictures of correctly aligned ones.

AVANT Aurora Ultimate 90 Assembly Manual _11
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Wrong alignment case #1:
Top gear too forward
Wrong alignment case #2:
Bottom gear too forward

12 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Correct tooth face alignment:
Flush alignment is easily achieved
because the kit brings four sets of
three bearings spacing washers of
0.1, 0.2 and 0.3mm thickness.
Combining them you can get from
0.1mm to 0.6mm spacing (0.1),
(0.2), (0.1+0.2), (0.3), (0.3+0.1),
(0.3+0.2), (0.3+0.2+0.1). In order
to align them flush you simply
select thinner washer shims for the
one that's too forward or thicker
for the one that's not forward
enough.

AVANT Aurora Ultimate 90 Assembly Manual _13
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
2) No Play:
The second and very important thing to make sure you have is that there is absolutely no
play between the gears.
In order to make sure that there is no play between the gears hold one of the shaft firmly
while trying to rotate the other one back and forth. There should be no movement on the
gear. If there is movement simply increase the thickness on BOTH shafts the SAME amount
so that the flush alignment from step 1 is not lost and try again.
Once set as described it'll take a few flights for the gears to set and break in.
3) Lubrication:
The same oil that will be left as residue from your flight session is used as lubricant. At the
beginning of the flight day drop a few drops of fuel rotate the main rotor a few turns and let
the alcohol evaporate for a couple of minutes leaving the oil residue for lubrication.
Remember the three steps:
1) Flush alignment
2) No Play
3) Lubrication
Bag #5: Battery / Radio Plate
Install battery blocks on the frames
and then the battery/radio plate on
them.
M3x8 (2) AV00-100-421 M3x10 (2) AV00-100-422
AV00-200-508
AV00-200-730
AV00-200-730

14 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Bag #6: Right Frame,
frame bellcrank and Tail
boom clamp.
Install the sacrificial tabs
and canopy mount posts as
previously done in the left
frame as well as the gear
ratio plate as shown in the
picture. Make sure the
plate's notch is facing back
toward the rear of the
helicopter. Install the tank
rubber mounts the same
way as explained before on
step 01.
Install the right frame onto the left side assembly as shown below.
M3 Locknut (2)
AV00-100-320
A
V00-200-511
M3x8 (2)
AV00-100-421
A
V00-200-625
(Short)
A
V00-200-505
A
V00-200-506
M3x6 (2)
A
V00-100-420
A
V00-200-624 (Long)
M3x8 (2)
M3 Locknut (2)
M3x8 (1) AV00-100-421
M3x10 (4)
A
V00-100-422
M3x8 AV00-100-421
M3x8 (1)
Do not tighten
the four M3x10mm
screws in the ratio
plate until the engine
is installed and the
clutch stack is aligned
with the en
g
ine.

AVANT Aurora Ultimate 90 Assembly Manual _15
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Install the boom clamps
with the through bolts as
shown. Do not tighten them
until the boom is installed.
Assemble the tail frame
bellcrank as shown.
Bag #7: CCPM System and Swashplate
M3x35 (4) AV00-100-428
M3 locknut (4)
A
V00-100-320
M3 washer (4)
A
V00-100-302
A
V00-200-753
AV00-100-619
M2.5x8 (1)
A
V00-100-410
M2.5 washer (1)
AV00
-
100
-
301
AV00-100-617
AV00-100-621 (Short)
AV00-200-667
M4x4 (1) Cup AV00-100-357 AV00-100-635
A
V00-200-260
A
V00-200-667
A
V00-200-302
A
V00-200-723 Tail
Bellcrank strai
g
ht
M3x18 (1) AV00-100-425 M3 Washer
1mm bearing spacer
A
V00-200-301
Start the thread by
using an M2 screw from
the bag that contains the
tailcase. Use Blue Loctite
in the screw. Apply the
same method for all M2
threads that go into plastic
Note: Boomclamp installation is
better left for the end when the boom is
ready for installation. Remember not to
tighten the clamps excessively or you
could crack the carbon boom.

16 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Install the seven balls and the guide pin on
the pre-assembled swashplate as shown.
AV00-100-622 (Long)
A
V00-200-668 (7)
AV00-100-618
AV00-200-667
AV00-100-620
AV00-100-619
M4x4 (1) Cup point
Setscrew AV00-100-357
M4x4 (1) Cup point Setscrew
AV00-100-357
M3x4 (3) AV00-100-350 Setscrew
Install three into the swashplate and don’t over
tighten them. Tighten them as needed to
eliminate
p
la
y
as the bearin
g
wears with use.
A
V00-200-620
A
V00-100-624

AVANT Aurora Ultimate 90 Assembly Manual _17
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Slide the Swashplate onto the main
shaft and install the CCPM guide with
the four screws as shown.
Bag #8: Fan hub, Fan, Clutch and motor mount sides
If using a governor install the magnet into the fan with
epoxy. Attach the fan to the fan hub with the four
round head screws then install the fan hub into the
engine by tightening the fan into the threaded
crankshaft. Lock the engine crankshaft in place by
using an engine lock from the back of the engine and
locking the piston rod in place. Once the fan is
tightened in place use the engine's washer and nut to
lock the fan in place. In most cases the engine washer
is not used. If you use the engine washer make sure
the clutch doesn’t bind against the clutch bell.
Install AV00-200-621 Main Shaft Collar
using two M4x4 (2) Flat AV00-100-351
A
V00-200-733
M3x8 (4)
A
V00-100-421
A
V00-200-740
M3x8 (4) Button (round) Head AV00-100-442
A
V00-200-607

18 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Install the clutch using the two M4
screws provided. Use blue Loctite to
secure them.
Insert the engine in place by
making the starter shaft fit into
the clutch one-way bearing. Use
blue Loctite to install the four
M4 screws provided that hold
the motor mount sides in place.
Use blue Loctite to install the
four M4 screws provided that
hold the engine in place. If
using a governor also install the
sensor plate. Use the location of
the sensor plate to mark the
location in the fan shroud so an
opening can be made in the fan
shroud to allow for the sensor to
clear.
M4x8 (2) AV00-100-430
AV00-200-290 One-way Bearing
AV00-200-603
M4x14 (4) AV00-100-433 AV00-100-608 M4x16 (4)
AV00
-
100
-
434
Add a few drops of oil to the
rollers to lubricate the one-way
bearing. Make sure you don’t get
any in the clutch shoes that could
make the clutch sli
p
.

AVANT Aurora Ultimate 90 Assembly Manual _19
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Bag #9: Fan shroud installation
Insert both fan shroud sides in place
Install the fan shrouds in place. In
order to insert them in place there are
notches in the back side that allow for
an easier insertion. Once located in
place use the four M3x10 screws
provided to secure them in place.
Join the two fan shroud halves
using the six M3x8 screws
provided.
M3x10 (4) AV00-100-422
A
V00-200-734
A
V00-200-734
M3x8 (6) AV00-100-421
Now that the engine is in place rotate the
starter shaft and make sure it’s aligned with
the one-way bearing. Tighten the eight
bearing block screws accordingly. And the
engine and motor mount sides bolts.

20 AVANT Aurora Ultimate 90 Assembly Manual
Note: Unless indicated otherwise all screws, balls and threads are installed with Blue Loctite
Bag #10: Landing gear installation
Insert the landing gear skids
into the landing gear struts as
shown. Use the frames as a
reference to space them
approximately where they go.
Insert the four M3x5 setscrews
but don't tighten them
completely until the assembly is
installed on the helicopter.
Using the provided hardware
install the back landing gear
struts on the frames as
shown. You might need to
squeeze the frames inward to
make the struts fit.
M3x5 (4) AV00-100-358
AV00-200-670
AV00-200-722
M3x10 (4)
A
V00-100-422
M3 washer (4)
A
V00-100-302
M3 locknut (4)
A
V00-100-320