Great Planes Giant Big Stik ARF - GPMA1224 - Manual (Page 26)

shall be readily available to both pilot and
spotter/helper. This switch shall be operated manually
and without the use of the Radio System.
5.3 There must also be a means to stop the engine from
the transmitter. The most common method is to
completely close the carburetor throat using throttle
trim; however, other methods are acceptable. This
requirement applies to all glow/gas ignition engines
regardless of size.
SECTION 6.0: RADIO REQUIREMENTS
6.1 All transmitters must be FCC type certified.
6.2 FCC Technician or higher-class license required for 6
meter band operation only.
The following recommendations are included in the Safety
Code not to police such items, but rather to offer basic
suggestions for enhanced safety. It is expected that IMAA
members will avail themselves of technological advances as
such become available, to promote the safety of all aircraft
and participants.
Servos need to be of a rating capable to handle the loads
that the control surfaces impose upon the servos. Standard
servos are not recommended for control surfaces. Servos
should be rated heavy-duty ounces of torque. For flight
critical control functions a minimum of 45 inch/ounces of
torque should be considered. This should be considered a
minimum for smaller aircraft and higher torque servos are
strongly encouraged for larger aircraft. The use of one servo
for each aileron and one for each stabilizer half is strongly
recommended. Use of dual servos is also recommended on
larger aircraft.
On-board batteries should be, at a minimum, 1000mAh up
to 20 lbs., 1200mAh to 30 lbs., 1800mAh to 40 lbs., and
2000mAh over 40 lbs. flying weight. The number and size of
servos, size and loads on control surfaces, and added
features should be considered as an increase to these
minimums. Batteries should be able to sustain power to the
on-board radio components for a minimum of one hour total
flying time before recharging.
Dependable, redundant and fail safe battery systems
are recommended.
The use of anti-glitch devices for long leads is recommended.
There is no maximum engine displacement limit, as it is the
position of this body that an underpowered aircraft presents
a greater danger than an overpowered aircraft. However, the
selections of engine size relative to airframe strength and
power loading mandates good discretionary judgment by
the designer and builder. Current AMA maximums for
engine displacement are 6.0 cu. in. for two stroke and 9.6
cu. in. for four stroke engines. These maximums apply only
to AMA Sanction competition events such as 511, 512, 515
and 520. All non competition events should be sanctioned
as Class C events, in which these engine size maximums do
not apply.
Generally, it is recommended that no attempt should be made
to fly a radio controlled model aircraft with a gasoline engine in
which the model aircraft weight would exceed 12 pounds per
cubic inch of engine displacement (underpowered), or be less
than 5 pounds per cubic inch of engine displacement
(overpowered). Example: Using a 3 cu. in. engine, a model
would likely be underpowered at an aircraft weight greater
than 36 pounds. With the same engine, an aircraft weighing
less than 15 pounds would likely be overpowered.
Servo arms and control horns should be rated heavy-duty.
Glass-filled servo arms and control horns are
highly recommended.
Control surface linkages are listed in order of preference:
1. Cable system (pull-pull). A tiller bar is highly
recommended along with necessary bracing.
2. Arrow-shaft, fiberglass or aluminum, 1/4" [6.4mm] or
5/16" [8mm] OD. Bracing every six (6) to ten (10) inches
is highly recommended.
3. Tube in tube (Nyrod). Bracing every few inches is highly
recommended. Inner tube should be totally enclosed in
outer tube.
4. Hardwood dowel, 3/8" OD. Bracing every six (6) to ten
(10) inches is highly recommended.
Hinges should be rated heavy-duty and manufactured
primarily for use in giant-sized aircraft. Homemade and
original design hinges are acceptable if determined to be
adequate for the intended use.
Clevis (steel, excluding heavy-duty ball links) and
attachment hardware should be heavy-duty 4-40 thread-
and-rod type. 2-56 Thread size rod is acceptable for some
applications (e.g. throttle). Clevises must have lock nuts and
sleeve (fuel tubing) or spring keepers.
Propeller tips should be painted or colored in a visible and
contrasting manner to increase the visibility of the propeller
tip arc.
❏
1. Fuelproof all areas exposed to fuel or exhaust residue
such as the wing saddle area, the framework around
the fuel tank hatch, the top of the fuel tank hatch, etc.
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.
CHECK LIST
26