SURFACE
LOW RATE TRAVEL
HIGH RATE TRAVEL
ELEVATORS: 1-1/4” UP - 1-1/4” DOWN
1-3/4" UP - 1-3/4" DOWN
AILERONS:
1” UP - 1” DOWN
1-1/2” UP - 1-1/2” DOWN
RUDDER:
1-7/8” LEFT - 1-7/8” RIGHT 2-1/4” LEFT - 2-1/4” RIGHT
THROTTLE:
FULL RANGE OF TRAVEL
NOTE: These measurements were taken as follows:
Elevator travel measured at the widest inboard trailing edge
Aileron travel measured at the inboard trailing edge
Rudder travel measured at the widest lower trailing edge
If you are using a computer radio, the following information may be
of help. Listed and explained below are types of control surface
mixing that would be desirable on this type of model and the effect
they have on the flight performance of the SOMETHIN' EXTRA
®
.
CONTROL SURFACE MIXING
MIXING
CONTROL SURFACES
EFFECT
FLAPERONS
AILERONS
SEE NOTE #1
ELEVATOR-FLAP
ELEVATORS and FLAPS
SEE NOTE #2
PRE-SET SWITCH
FLAPS and ELEVATORS
SEE NOTE #3
NOTE #1 - Using typical modern computer radios and two
separate aileron servos, it is possible to use the ailerons as flaps.
In flight, lowering both ailerons as flaps typically causes the model
to pitch down, requiring some corrective "up" elevator input to
maintain level flight. Some transmitters have a rotary "Flap" knob
that allows the pilot to select the best flap position for any given
need or wind condition. With each aileron servo plugged into a
separate channel in the receiver, lowering both ailerons as flaps
still allows independent movement of each aileron to control roll.
This is a versatile mixing feature as long as the pilot maintains
elevator input as needed.
NOTE #2 - Elevator To Flap mixing is also a good feature. It
interfaces the elevators to the flaperons, allowing both surfaces to
work together to maintain very slow, straight, and level flight.
When mixed together, the flaperons travel downward while the
elevators travel upwards at a pre-programmed rate.
Likewise,
deploying the flaperons upwards causes the elevators to travel
downwards, again at a pre-programmed rate. This mixing feature
can be used to give your SOMETHIN' EXTRA
®
ARF the ability to
perform incredibly sharp turns and super tight loops.
NOTE #3 - As mentioned in Note #1, some transmitters have
rotary knobs for the "flap" channel. However, some transmitters
have 3-position switches that allow pre-set flap and elevator
positioning. There are even some transmitters that have both
types of switches. The 3-position switch typically allows for three
different flap positions. For example: Switch setting #1: Raise the
flaperons 10° or so, causing them to act as spoilers on a sailplane
which causes the airplane to make faster descents for those quick
landings sometimes called for in fun-fly contests. Switch setting
#2: With the switch in this position, the flaperons are held in
neutral position - with the exception of "Elevator To Flap" mixing for
normal flying. Switch setting #3: Lowers the flaperons to a pre-set
location (say, 30° or so). This setting would allow the airplane to
make incredibly slow landings or even to hover or appear to fly
backwards in certain wind conditions.
Double-check the entire radio installation and remedy any
problems now. Make sure that all five servos have their output arm
screws back in place and tightened. We also suggest that you
periodically check the available voltage in your receiver and
transmitter battery packs, using a good ESV (Expanded Scale
Voltmeter) to avoid battery related problems. Last, no matter how
good you may think your radio system is, make it a routine part of
your pre-flight procedures to always perform a thorough range
check before every flying session.
DECAL APPLICATION:
The decals supplied with your SOMETHIN' EXTRA
®
ARF kit are
high quality Mylar with an extremely aggressive adhesive. These
are not die-cut and must be cut from the sheet with a hobby knife
and a sharp #11 blade or with sharp scissors.
We suggest the following method to accurately apply these decals.
Carefully cut out the decal and lift it off the sheet with tweezers.
Use a product like SIG Pure Magic Model Airplane Cleaner,
Fantastic
®
, or Windex
®
to spray the area of the model that will
receive the decal. Then spray the adhesive side of the decal as
well. Lightly position the decal in place on the model. The liquid
cleaner allows the decal to slide easily into the desired position -
do not press down on the decal. Once in position, hold the decal
lightly in place with your finger and use a paper towel to gently dab
the excess liquid away. Use a small squeegee to now set the decal
in place, removing all excess liquid and any trapped air bubbles.
The SIG 4" Epoxy Spreader - #SIGSH678 - is perfect for this job.
Mop up any excess cleaner with a dry cloth and allow the decals
to set overnight. They will be solidly adhered to the model without
any air bubbles.
CENTER OF BALANCE:
We suggest a beginning Center of Balance (CG) location of 3-1/2"
back from the leading edge of the wing. This CG location is fairly
"mild" and should be used for initial test flights. Later, when you're
more comfortable with the airplane and how it flies, this
CG location can be relocated further back to yield even wilder
maneuvers. When doing this, never move the CG location further
back than 1/4" without flying the airplane first. You need to be
aware of how your airplane flies with an aft CG location and you
would be wise to "sneak up" up on this information rather than find
out the hard way!
The easiest way to balance this model is upside down, using a
balancing fixture. We made our fixture, using a pair of 1/4" dowels
with rubber tips to protect the finish. Simply measure back 3-1/2"
from the leading edge of the wing and mark that location on the
wing with a non-permanent marker pen or thin strips of tape. Mark
the CG location on both wing panels. Turn the airplane over and
position the ends of the balancing fixture at the marks just made.
Ideally, the model should be right on or very close to the
recommended 3-1/2" point. If it is nose-heavy, the battery pack
16