electric arf - Atlanta Hobby

Instruction Manual
©Copyright 2006 EXTREME FLIGHT RC, Ltd.
Thank you for your purchase of the Extreme Flight RC 45” Extra 300 Electric ARF. This
aircraft was designed to provide maximum performance and fun in a realistic looking,
lightweight, fully aerobatic park flyer. Using an inexpensive and efficient brushless
outrunner motor and speed controller and a single high discharge 3S1P Lithium Polymer
battery, the Extra 300 provides unlimited performance capability.
Great care was taken to design a light weight yet robust airframe. Expert engineering and
modern laser cutting methods in conjunction with a carbon fiber wing tube and composite
control horns keep weight to a minimum. Unique features such as the ram air equipped
motor box, 2 piece plug in wings, and magnetically retained canopy/hatch make for quick
easy assembly and instantaneous access to the interior of the plane and battery tray. The
Extra 300 can truly be assembled in an evening-buy it one day, fly it the next!
As with all Extreme Flight RC airplanes, the proof is in the flying! Due to the close
proximity of the wing and stab to the thrust line, the Extra 300 is a very neutral flying
aircraft. It flies precision aerobatics remarkably well and allows you to practice your
IMAC sequence almost anywhere. The slightly stretched fuselage makes for a plane that
tracks like a pattern ship and the lightweight wings minimize over rotation in snaps. On a
calm day you’ll be amazed at how well this thing flies the sequences.
If 3D is your thing then strap in! The Extra 300 does it all with ease. Beautiful, slow
high alpha knife edge passes. FLAT spins both upright and inverted, rock solid elevators
and harriers. Tremendous aileron authority and insane roll rate from the massive
ailerons. The Extra does beautiful waterfalls and is capable of performing large round
knife edge loops. You won’t believe how much fun this thing is to fly!
Sport flyers fear not! Just because you’re not a 3D hot dogger or IMAC flyer doesn’t
mean you can’t enjoy the Extra 300. With reduced rates the Extra 300 is a very easy
plane to fly. Its super light wing loading allows it to land at a walk. It will instill
confidence and allow you to improve your flying skills. When you’re ready for more
advanced aerobatics, flip the dual rate switch and hang on!
As with any high performance aerobatic aircraft, great care must be taken to avoid excess
speed. Excess speed will lead to control surface flutter and quite possibly the complete
destruction of your aircraft. Don’t let this happen to you! Always have the motor at idle
when the airplane is pointed down and reserve full throttle for vertical climbs. Make sure
you have adequate mechanical advantage in your control linkage set-up. If you are
unsure about this, have a more experienced flyer look over your set-up before flying.
Extreme Flight RC, Ltd. in no way warranties its aircraft against flutter. As with all of
our planes, we put the Extra through a rigorous flight testing regime and have not
experienced any control surface flutter.
The Extra was designed around the Torque 2818T/900 Brushless Outrunner motor and
Airboss 35 AMP ESC. This is the best choice for powering the Extra, providing plenty
of power for any maneuver imaginable. Other outrunner motors in this class will work as
well but may require slight modification to the motor mount.
The Extra is very easy to assemble. Take a few minutes to read this manual before
beginning assembly to get familiar with the process.
Let’s get started!
Extreme Flight RC
Extra 300 Electric ARF
Instruction Manual Addendum
In an effort to make your experience with the Extreme Flight RC Extra 300 Electric ARF
as enjoyable and hassle free as possible, we have included this addendum to further
clarify some of the assembly processes and offer a couple of tips to help ensure the
longevity of your aircraft.
1. Customer feedback has indicated that several folks are having difficulty getting a
good bond between the elevator halves and the carbon fiber joiner. The integrity
of this joint is paramount to the successful operation of your Extra. If this joint
fails, flutter will occur which could result in the destruction of your aircraft. In
order to make this assembly easier to secure and increase the strength of the bond
we have included a 9.5” x 1/8” piece of flat carbon strip to affix to the elevator
and carbon joiner. First glue the carbon joiner in place as per the instruction
2. Use a straight edge and #11 hobby blade to remove a strip of covering from the
bottom of the elevator that extends from the end of the carbon joiner 2.5” in each
direction. Lightly sand the joiner flat so the carbon strip will lay flat against it.
Also scuff the flat carbon on the side that will be glued to the elevator halves and
carbon joiner.
Use medium CA to bond the flat carbon strip to both the elevator halves and the
carbon tube joiner. This will increase the bonding surface and stiffen the elevator
considerably with a very small weight gain. You will need to notch the elevator
control horn to clear the flat carbon stiffener. If you are planning to use a bigger
than recommended power system we highly recommend that you add another
piece of flat carbon to the bottom of the horizontal stabilizer at the trailing edge.
4. There are extra hinges included in the hardware package. Use one of these hinges
at the bottom of the rudder just above the rudder control horn. You will need to
make a slot in both the rudder and rudder post to accept this hinge. Please see
picture for location of hinge. Use thin CA to secure the hinge.
5. There are 2 additional pieces of balsa triangle stock included with the Extra.
These are to further reinforce the motor box if larger motors are used. These
pieces are to be glued into the inner edges of the motor box. If using the stock
power system these pieces are not needed. Just make sure that all joints in the
motor box and its attachment point to the fuselage are glued securely.
6. There is an error in one of the photos in the instruction manual that is causing
some concern due to excessive binding in the aileron control linkage. The aileron
servo should be oriented with the output shaft away from the trailing edge as
shown in this picture. This reduces the angle and relieves the binding linkage.
7. There are 2 sheeted areas on the bottom of the fuselage just behind the canopy.
The covering is to be removed from these areas to allow for proper flow thru of
the cooling air from the intakes up front.
8. A lot of effort went into creating a scale spinner for this model. Some have
expressed dissatisfaction with the spinner and reported excessive vibration.
Please take a few moments and put the spinner on one of the commercially
available magnetic balancers. A few drops of CA on the inside of the spinner on
the light side will do the trick. The spinner is an exact outline of the full scale
spinner. Always balance your props and spinners for maximum performance and
motor/engine and airframe longevity.
9. You will need to open the hole in the motor mounting plate to clear the C-clip on
the motor. Use a tapered reamer or #11 blade to remove enough material to allow
the C-clip to clear the surrounding wood and rotate freely.
Thanks again for your purchase of the Extreme Flight RC Extra 300 Electric ARF.
We hope this addendum will help you to assemble your aircraft easier and allow you
to get flying faster.
See you at the flying field!
Wing assembly
1. Locate a wing panel. Check to see that all hinges are centered between the wing
and aileron. Hold the aileron fully deflected and apply a drop of thin CA to each
hinge. Flip the wing over and repeat.
2. Use a #11 hobby blade to remove the covering over the servo bay. Install the
aileron servo using the manufacturer supplied mounting screws. Route the servo
lead out of the root of the wing.
3. Locate the composite aileron control horn, aileron pushrod with z-bend and ezconnector. Remove the covering over the mounting hole for the control horn with
your #11 blade. Glue the control horn in place with medium CA. Electronically
center your servo and mount the ez-connector to the servo arm. Place the z-bend
in the aileron control horn and the other end of the wire into the hole in the ezconnector. Center the aileron and tighten the screw in the top of the ez-connector
to retain the aileron pushrod wire. See picture.
4. Repeat for the other wing.
That’s it! You are done with the wings!
Fuselage Assembly
1. Lets mount the landing gear first. Locate the aluminum landing gear, (4) 3mm
machine screws ( 2 long, 2 short), (4) wheel collars, the two wheel pants and
wheels and the 2 small plywood squares. Use medium CA to glue the plywood
square to the inside of each wheel pant, centered in the wheel pant opening. You
may need to open the hole in the wheel pant slightly to allow plenty of clearance
for the wheel. Use a drum sanding wheel for this with your moto-tool.
2. Locate the 2 longest 3mm screws and hex nuts. These are the wheel axles. Insert
the screw through the pre-drilled hole in the landing gear and retain with the hex
nut. It would be a good idea to use a drop of blue loc-tite here. Slide one of the
wheel collars onto the axle, followed by the wheel, followed by another wheel
collar. Slide the wheel pant over this assembly before tightening the set screws in
the wheel collars to make sure the wheel is positioned so that it fits in the opening
in the pants. When satisfied, tighten the setscrews in the wheel collars. Position
the wheel pants over the wheels (you will need to slot the wheel pant so that it
will slide down over the axle, again quick work with a moto-tool and proper
attachment). Drill a small hole in the landing gear and into the ply square you
glued into the wheel pants and use one of the small machine screws to secure.
You may also want to put a drop of med CA between the wheel pant and
aluminum gear. The picture below will make this much clearer.
3. Apply a drop of loc-tite to each screw and insert it through the landing gear and
into the pre-installed blind nut in the landing gear plate.
4. Locate the motor box assembly and the 2 laser cut triangular motor box supports.
Place the tabs in the motor mount assembly into the firewall and push down so that
they lock into place. Install the triangular supports as shown. Wick thin and medium
CA into all joints and allow to cure. Locate the 2 clear plastic air scoops and glue
them into place as shown.
5. Use the manufacturer supplied mounting hardware and mount the motor and ESC
as shown. The hole for the prop shaft may need to be reamed slightly to clear the
C-clip on the motor.
Position the canopy/hatch in place and slide the cowl over the first former. Use
your spinner (a 2” spinner is the proper size) on the prop shaft to make sure the
cowl is aligned properly. View the cowl from the side and top view to insure it is
positioned properly. When satisfied, secure the cowl in place with a few pieces of
masking tape. Use a small drill bit to drill through the cowl and into the 4
mounting tabs. Secure the cowl with 4 small wood screws included in the
hardware package. I highly recommend that you soak the cowl mounting tabs
with thin CA before drilling.
7. Locate the horizontal stabilizer. Viewing the bottom of the stabilizer, use a #11
blade to remove the covering from the two notches at the leading edge of the
stabilizer. Also remove the covering from the slot for the horizontal stabilizer in
the fuselage. Slide the stabilizer into place and measure from several angles to
insure that it is square to the fuselage and wing. Sand or shim the slot as needed
to insure proper alignment. Use a fine felt tipped marker to make some reference
marks and remove the stabilizer from the plane. Use a hobby knife to remove the
covering from the stab where it will attach to the fuselage to insure a wood to
wood bond. Be very careful not to score the wood which could potentially
weaken the stabilizer. DO NOT GLUE THE STABILIZER IN PLACE YET!!!!
Locate the elevator halves and the carbon fiber joiner tube. Place the elevator
halves on a flat surface and tack glue the carbon tube in place. Check the
alignment, then mix up some 30 minute epoxy and form a fillet between the
carbon tube and elevator halves. This joint is crucial so take your time here.
8. After it is dry, flip the elevator over so that the counterbalances are facing the
rear of the plane. Insert the elevator into the slot. Once it is in position, insert the
horizontal stab into place. Re-check alignment and when satisfied, glue the
stabilizer in place with CA or a small amount of epoxy. Once this is dry, slide the
elevator into position and glue the hinges in place with thin CA. Be sure to leave
enough space between the stab and elevator for maximum deflection. Seal the
hinge line on the bottom with Blenderm tape. (DO NOT OMIT THIS STEP!!!)
9. Locate the vertical fin and rudder. Remove the covering from the vertical fin
where it will be glued into the fuselage. Glue the vertical fin in place, making
sure that the trailing edge of the fin is aligned with the rear of the fuselage.
10. Locate the phenolic double rudder control horn. Remove the covering from the
slot near the bottom of the rudder and insert he control horn into the slot. Glue in
place with medium CA or epoxy. Attach the tailwheel assembly as shown in the
picture and secure with a small piece of strapping tape. Slide the rudder into
position and glue the hinges in place with thin CA.
11. Locate the elevator control horn and glue in place with medium CA or epoxy.
Use a #11 blade to remove the covering from the elevator servo slot and install
the servo using the manufacturer supplied mounting hardware. Place an ezconnector on the servo arm. Locate the elevator pushrod and insert the z-bend
into the phenolic control horn and the other end into the ez connector.
Electronically center the servo and then tighten the screw in the ez connector to
clamp down on the pushrod, while making sure the elevator is in the neutral
position. You may need to put a small bend in the pushrod. Pictured is the Hitec
HS-55 sub-micro servo, however we strongly recommend using a stronger servo
if you intend to set-up the Extra for 3D flying. We have had great success with
the Hitec HS-56 and the JR 281.
12. Mount the rudder servo as shown inside the fuselage. We highly recommend
using a more powerful servo for the rudder such as the Hitec HS-56, HS-65 or JR
281 to prevent control surface blow back. Use the supplied hardware to assemble
the pull-pull cable system. At the rudder control horn end, the cable will be
threaded through the control horn and secured with a small aluminum tube which
is crimped around the cable. At the servo end, the cable is threaded through the
hole in the connector as shown and then inserted into the ez connector. Center the
servo electronically and make sure the rudder is in the neutral position. Tighten
the screw in the ez connector. Make sure the cables are taut, but not overly tight,
which may cause the servo to bind.
10. Install the receiver as shown using Velcro. Use Velcro to secure the battery to
the battery tray and use a Velcro strap around the battery.
11. Use the supplied nylon bolts to secure the wings to the fuselage.
This concludes the assembly of the Extra 300.
Radio Set-up and flight tips.
CG range for the Extra is from 3.50”- 4.00” from the leading edge of the wing
measured at the wing root. CG should be easy to achieve by moving the battery
along the length of the battery tray. Adjust to fit your flying style.
Control surface recommendations are as follows:
Elevator- 10 degrees low rates, 45+ degrees high rates.
Rudder- 20 degrees low rates, 45+ degrees high rates.
Aileron- 20 degrees low rates, 45+ degrees high rates.
Use exponential function to achieve the best “feel” for your particular flying style. I
highly recommend that you take the time to set up rates for precision flying and
separate rates for 3D. The Extra is capable of flying very precise maneuvers, and
proper rates and CG will allow you to experience this to the fullest extent. Trying to
fly precision aerobatics with 3D rates is an exercise in futility. Spend some time
dialing in and trimming your plane and you will be rewarded with a great flying
Thanks again for your business!
See you at the flying field!
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