Great Planes CAP 232 1.60 ARF - GPMA1410 - Manual (Page 32)

ADDITIONAL IMAA GENERAL RECOMMENDATIONS
The following recommendations are included in the Safety
Code not to police such items, but rather to offer basic
suggestions for enhanced safety.
• 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. 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 elevator half is strongly recommended. Use of dual
servos is also recommended for larger aircraft.
• On-board batteries shall be 1000 mAh up to 20 lbs., 1200
mAh to 30 lbs., 1800 mAh to 40 lbs. and 2000 mAh 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 onboard radio
components for a minimum of one hour total flying time
before recharging.
• 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 selection 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 Sanctions concerning
competition events (such as 511, 512, 515 and 520) and,
as such, the maximums apply. All IMAA (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
twelve (12) pounds (underpowered) per cubic inch of
engine displacement, or be less than five (5) pounds
(overpowered) per cubic inch of engine displacement.
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 wheels 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" or 5/16" 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 for
Giant Scale use primarily. 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 threaded
rod type. 2-56 threaded size rod is acceptable for some
applications (e.g. throttle). Clevis is to have lock nuts and
sleeve or spring keepers.
• Propeller tips should be painted or colored in a visible and
contrasting manner so as to increase the visibility of the
propeller tip arc.
❏
1. Fuel proof all areas exposed to fuel or exhaust
residue such as the cowl ring, cowl mounting blocks,
wing saddle area, etc.
❏
2. Check the C.G. according to the measurements
provided in the manual.
❏
3. Be certain the battery and receiver are securely
mounted in the fuse. Simply stuffing them into place
with foam rubber is not sufficient.
❏
4. Extend your receiver antenna and make sure it has a
strain relief inside the fuselage to keep tension off the
solder joint inside the receiver.
❏
5. Balance your model laterally as explained in
the instructions.
❏
6. Use thread locking compound to secure critical
fasteners such as the set screws that hold the wheel
axles to the struts, screws that hold the carburetor arm
(if applicable), screw-lock pushrod connectors, etc.
❏
7. Add a drop of oil to the axles so the wheels will
turn freely.
❏
8. Make sure all hinges are securely glued in place.
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
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