Top Flite TOPA0700 - Manual (Page 43)

and higher torque ser
v
os are strongly encour
aged
fo
r larger aircr
aft.
The use of one ser
v
o
f
or each
aileron and one f
or each ele
v
ator half is strongly
recommended.
Use of dual ser
v
os is also
recommended f
o
r larger aircr
aft.
On-board batter
ies shall be 1000 mAh up to 20 lbs
.,
1200 mAh to 30 lbs
., 1800 mAh to 40 lbs
.
and 2000
mAh o
ver 40 lbs
.
flying w
eight.
The n
umber and siz
e of
ser
vo
s,
siz
e and loads on control surf
aces
, and added
features should be considered as an increase to these minim
ums
.Batter
ies should be ab
le to sustain po
w
er to
the onboard r
adio components f
o
r a minim
u
m of one
hour total flying time bef
ore recharging.
Both redundant and f
ail-saf
e batter
y systems
are recommended. The use of anti-glitch de
vices f
or long leads
are recommended. There is no maxim
um engine displacement limit, as
it is the position of this body that an under
po
w
ered
aircr
aft presents a g
reater danger than an
o
v
er
po
w
ered aircr
aft.
Ho
w
e
v
e
r, the selection of
engine siz
e relativ
e to airfr
ame strength and po
w
e
r
loading mandates good discretionar
y judgment b
y
the designer and b
uilder
.
Current AMA maxim
ums
for engine displacement are 6.0 cu.
in.
for tw
o-strok
e
and 9.6 cu.
in.
for f
our-strok
e engines
.
These
maxim
ums apply only to AMA Sanctions concer
ning
competition e
v
ents (such as 511, 512, 515 and 520)
and, as such, the maxim
ums apply
.
All IMAA (non
competition) e
v
ents should be sanctioned as Class
“C”
e
v
ents
, in which these engine siz
e maxim
ums do
not apply
.
Gener
ally
, it is recommended that no attempt should
be made to fly a r
adio controlled model aircr
aft with
a gasoline engine in which the model aircr
aft w
eight
w
ould e
xceed tw
elv
e (12) pounds (under
po
w
ered)
per cubic inch of engine displacement, or be less than fiv
e (5) pounds (o
v
e
rp
o
w
ered) per cubic inch of
engine displacement.
Example:
Using a 3 cu.
in.
engine
, a model w
ould lik
ely be under
po
w
ered at an
aircr
aft w
eight g
reater than 36 pounds
.
W
ith the
same engine
, an aircr
aft w
eighing less than 15
pounds w
ould lik
ely be o
v
er
po
w
ered.
Ser
v
o
ar
ms and wheels should be r
ated hea
vy duty
.
Glass-filled ser
v
o
ar
ms and control hor
ns are
highly recommended. Control surf
aces linkages are listed in order
of pref
erence:
1.
Cab
le system (pull-pull).
A tiller bar is highly
recommended along with necessar
y br
acing.
2.
Arro
w Shaft, fiberglass or alumin
um, 1/4" or 5/16"
[6 or 8mm] O
.D
.
br
acing e
v
er
y six (6) to ten (10)
inches is highly recommended. 3.
T
ube-in-tube (n
yrod).
Br
acing e
v
er
y f
e
w inches is
highly recommended.
Inner tube should be totally
enclosed in outer tube
.
4.
Hardw
ood do
w
el, 3/8" O
.D
.
br
acing e
v
er
y six (6)
to ten (10) inches is highly recommended. Hinges should be r
ated hea
vy duty and
man
uf
actured f
or Giant Scale use pr
imar
ily
.
Homemade and or
iginal design hinges are
acceptab
le if deter
mined to be adequate f
or the
intended use
.
Cle
vis (steel, e
xcluding hea
vy-duty ball links) and
attachment hardw
are should be hea
vy duty 4-40
threaded rod type
.2
-56 threaded siz
e
rod is acceptab
le
fo
r some applications (e
.g.
throttle).
Cle
vis is to ha
ve
loc
k n
uts and slee
ve
or spr
ing k
eepers
.
Propeller tips should be painted or colored in a visib
le and contr
asting manner so as to increase the
visibility of the propeller tip arc.
FL
YING
The
T
op Flite Giant P-51D Mustang ARF is a g
reat-
flying model that flies smoothly and predictab
ly
.
The
Mustang does not, ho
w
e
v
e
r, possess the self-
reco
v
e
ry
char
acter
istics of a pr
imar
y R/C tr
ainer and
should be flo
wn only b
y
e
xper
ienced R/C pilots
.
Fuel Mixture Adjustments A fully co
wled engine ma
y r
un at a higher
temper
ature than an un-co
wled engine
.
F
or this
reason, the fuel mixture should be r
ichened so the
engine r
uns at about 200 r
p
m belo
w peak speed.
By
running the engine slightly r
ich, y
ou will help pre
v
ent
dead-stic
k landings caused b
y
o
v
erheating.
CA
UTION
(THIS APPLIES
T
O
ALL
R/C
AIRPLANES):
If
, while flying, y
ou notice an alar
ming
or un
usual sound such as a lo
w-pitched
“b
uzz,
”
this
ma
y indicate control surf
ace
flutter
.
Flutter occurs
when a control surf
ace (such as an aileron or
ele
vator) or a flying surf
ace (such as a wing or stab)
rapidly vibr
ates up and do
wn (thus causing the
noise).
In e
xtreme cases
, if not detected
immediately
, flutter can actually cause the control
surf
ace to detach or the flying surf
ace to f
ail, thus
causing loss of control f
ollo
w
ed b
y
an impending
cr
ash.
The best thing to do when flutter is detected is
to slo
w the model
immediatel
y
b
y
reducing po
w
e
r,
then land as soon as saf
ely possib
le
.
Identify which
surf
ace fluttered (so the prob
lem ma
y be resolv
ed)
b
y
chec
king all the ser
vo
g
rommets f
o
r deter
ior
ation
or signs of vibr
ation.
Mak
e cer
tain all pushrod
linkages are secure and free of pla
y.
If it fluttered
once
, under similar circumstances it will probab
ly
flutter again unless the prob
lem is fix
ed.
Some things
which can cause flutter are;
Excessiv
e hinge gap;
Not mounting control hor
ns solidly;
P
oor fit of cle
vis
pin in hor
n;
Side-pla
y of wire pushrods caused b
y
large bends;
Excessiv
e free pla
y in ser
vo
gears;
Insecure ser
vo
mounting;
and one of the most
pre
valent causes of flutter
;
Flying an o
ver-po
w
e
red
model at e
xcessiv
e speeds
.
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