Top Flite TOPA0415 - Manual (Page 61)

Section 3.0: Safety Check
3.4 Flight Testing: All Giant Scale R/C aircraft are to
have been flight tested and flight trimmed with a
minimum of six flights before the model is allowed to
fly at an IMAA Sanctioned event.
3.5 Proof of Flight: The completing and signing of
the Declaration section of the Safety Inspection form
by the pilot (or owner) shall document as fact that
each aircraft has been successfully flight-tested and
proven airworthy prior to an IMAA event.
Section 5.0: EMERGENCY ENGINE SHUT OFF
(kill switch)
5.1 All magneto spark ignition engines must have a
coil grounding switch on the aircraft to stop the
engine. This will also prevent accidental starting of
the engine. This switch shall be readily available to
both pilot and helper. This switch is to be operated
manually and without the use of the radio system.
5.2 Engines with battery power ignition systems
must have a switch to turn off the power from the
battery pack to disable the engine from firing. This
will also prevent accidental starting of the engine.
This switch shall be readily available to both pilot
and 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
close the carburetor throat completely 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.
Additional General Recommendations
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 is
recommended.
The use of anti-glitch devices for long leads are
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 judgement 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 surfaces 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"
O.D. 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" O.D. 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.
- END OF IMAA SAFETY CODE -
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