The ailerons and flaps are controlled with HS-7245MH servos. Aluminum 1.25-inch servo horns were also used.
so that it was even on both sides of the
I used a tape measure to determine
the distance from the tips of the
horizontal stabilizer to the wing tube,
as well as the distance on each side of
the fuselage. I also checked to make sure
that the stabilizer ran parallel with the
wing tube, and no adjustments were
This is the one place where you
must make sure that you measure
several times before applying any glue.
After checking several times, I glued
the stabilizer in place with CA glue.
After the stabilizer was set, I glued on
the elevator using the CA hinges, and
then glued in the elevator control horn.
I connected the rudder and elevator
servos to 24-inch extensions, securing
them with heat-shrink tubing, and
installed them in the fuselage.
The motor mounts directly to
the firewall, which has a fiberglass
front glued to it to prevent crushing
and to add strength. Four bolts with
threadlocker hold the motor in place
and the ESC is mounted to the bottom
of the motor box using zip ties.
I scuffed the scale turbine exhaust
stacks and adhered them to the cowl
using welder’s glue. I then
mounted the cowl, using
masking tape to hold
the cowl in place while I
drilled the mounting holes.
To ensure everything was
square before drilling the
cowl holes, I mounted the
spinner and installed the
canopy/hatch to ensure
that everything had the
I installed the receiver
in the aft end of the hatch
plenty of room for the
flight battery. The inside
of the fuselage is huge,
allowing many sizes of
batteries to be used in
The only thing left to do
at this point was to make
the pushrods and install
them. The ball links are
tight. I found that it helped
to open them slightly on the end with an
X-Acto knife to allow the threaded rod
to get some bite.
When the pushrods started to thread
into the ball link, I used a couple of
Allen wrenches through the links to gain
some leverage while threading the links.
I then installed the pushrods using the
As mentioned earlier, the flaps on this
aircraft have a full range of travel. I chose
to set up three modes for my aircraft.
The first was a conventional flap setting
with the flaps assigned to a slider switch
on my 14SG so that I could position the
flaps in any lower position.
The second setup was a mix that
combined the flaps with the ailerons,
essentially creating a full-span aileron on
the wing. The third mix can be called
crow, butterfly, and/or air brake. This
mode deflects the flaps and ailerons
opposite of each other to slow the
airplane. With the flap and air brake
mix, a little elevator trim was needed to
prevent the airplane from climbing or
pitching over when these modes were
In the case of standard flaps, the
airplane would want to pitch up,
so some down-elevator mix was
programmed in. In the case of the air
brake, the model wanted to pitch over,
so some up-elevator was programmed.
The manual gives a great starting
point for setting the throw of the control
surfaces, but from past experience and
knowing how I like my airplanes to feel,
I set all control surfaces to deflect at
least 45° on high rate, and dialed in low
rates of approximately a quarter of the
high rates. I later fine-tuned these to my
I had three Lipo batteries to try in 6S
3,000; 3,300; and 5,000 mAh sizes. I
started with a 3,000 mAh LiPo battery.
I figured out where each battery needed
to be placed to give the airplane the
right center of gravity (I started on the
wing tube). After a successful range
test, I took to the air and had a pleasant
flight. The model handled well and felt
light. It was stable and didn’t appear to
have any unusual tendencies. No trim
was required, so I started to dial in the
I found that the huge elevator had
a lot of authority, so I dialed down the
55 Model Aviation JULY 2016