be corrected.
In the case of a model that balances nose heavy, the correction to
make it balance level is fairly easy. The heaviest component in the
model is typically the battery pack and this can be repositioned
further back in the fuselage as needed to make the model balance
correctly.
In the case of a tail-heavy model, weight has to be
brought forward in the fuselage to get the airplane to balance level.
This can be achieved several ways but the most effective is to
move the battery pack forward as needed. In the unlikely event
that more weight is needed then you may have to add lead weight
to the firewall to achieve the correct balance. In any case, it is
imperative that you establish the correct C.G. location with your
model before you fly it.
CONTROL MOVEMENTS:
The following surface control movements for the Waco SRE ARF
model are based on our experience with our prototype models.
These movements have provided us with a very smooth flying
model. We urge you to use these surface movements for your
initial test flight set up and then change them incrementally to best
suit your own particular flying style. This is especially true with the
elevators.
The counter-balanced elevators on the Waco are
powerful and on our models, the suggested initial movement given
below has never been changed.
Note that we have also included our exponential inputs, along with
the percentage of aileron/rudder mixing that we use. Because all
pilots have differing opinions about what they like or dislike in
control authority, these numbers can certainly be changed to suit
your own flying style. Note that the following measurements are
taken from the inboard end of the tapered ailerons and at the
widest trailing edge point of the rudder and elevators:
AILERONS:
3/4" Up - 3/4" Down
ELEVATORS:
7/8" Up - 7/8" Down
(with 20% Exponential)
RUDDER:
1-5/8" Left - 1-5/8" Right
AILERON TO RUDDER MIX:
15% Rudder Movement
FLAPS:
Position #1: 5/8" = 15
O
Position #2: 1-7/32" = 30
O
(max suggested travel)
FLYING:
If you have carefully followed these assembly instructions, test
flying your new Waco SRE model should be a lot of fun! We repeat
this in all of our assembly manuals and we'll do it again now; when
it comes to test flying this or any new airplane, do yourself a favor
by choosing a day that is calm, with little or no wind.
These
conditions allow you to much better evaluate and more accurately
adjust any needed flight trim inputs. Take all necessary steps to
eliminate any potential problems at the field, especially in the
set-up of the engine. A good running, reliable engine is a must in
the ultimate success of this or any airplane. Take the time to solve
any engine related problems before trying to fly your model. Just
to give you a little more incentive to get your engine running
reliably, we can tell you that the Waco can certainly glide in a
dead-stick situation, but not very far! Two wings, a round cowl,
wheel pants and flying wires all represent a reasonable amount of
aerodynamic drag.
CENTER OF GRAVITY:
Establishing the correct Center of Gravity (C.G.) for this or any R/C
model aircraft is critical to its ultimate success in the air. Measured
next to the fuselage, the recommended starting balance point for
the Waco SRE ARF is located 4-3/8” (111.1 mm) behind the
leading edge of the top wing. Note - the 4-3/8” C.G. location is
taken from the forward most part of the leading edge, not the
tapered-in section next to the windshield.
This measurement
equates to a 29% C.G. location.
At the wing tips, this same C.G.
location measures 5/16” behind the main wing spar, on the bottom
of the top wing panels. To do this as accurately as possible, we
made a simple fixture from scrap balsa. This fixture works on
either side of the fuselage, accurately giving us the 4-3/8” location.
On our models, we used thin pieces of tape to note the C.G.
location on the bottoms of the top wing panels, next to the
fuselage.
For reference, the finished Saito 1.00 powered Waco SRE, shown
in this manual weighs exactly 9 pounds, 8 ounces and required no
lead to balance.
This finished weight includes the 1100 mAh
airborne battery pack and the onboard glow system, shown in this
manual.
Because of the Waco's two wings and generally large size, the use
of a balancing fixture is not very practical. However, you can either
balance the model from the wing tips using the 5/16” measurement
- taken from the back edge of the bottom main wing spar - or you
can balance the airplane at the marks made against the fuselage,
using your fingertips. Note that the model is always balanced with
the fuel tank empty.
When balancing the model at the predetermined C.G. location, the
model must balance level.
If the nose hangs down when
suspended at the proper C.G. location, it means that the model is
nose heavy. Likewise, if the tail hangs down, the model is tail
heavy. If either of these conditions exist with your model, they must
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