Model type: Semiscale warbird trainer
Skill level: Beginner (with help) to advanced
Wingspan: 54. 7 inches
Wing area: 574 square inches
Wing loading: 22 ounces per square foot
Wing cube loading: 11
Length: 47. 7 inches
Weight: 5 pounds, 8 ounces
Engine: Evolution 8cc gas engine (installed)
Construction: Laser-cut balsa and light plywood
Covering/finish: UltraCote covered in the 334th Fighter Group scheme
Street price: $399.99
Engine used: Evolution 8cc gas engine (installed)
Receiver battery: E-flite 2S 8.4-volt 1,250 mAh 20C LiPo (installed)
Propeller: 12 x 6 sport
Radio system: Spektrum DX18 G2; four 37-gram E-flite HV Digital
servos (installed); AR636 SAFE receiver (installed)
Ready-to-fly weight: 5 pounds, 8 ounces
Flight duration: 20-plus minutes
• Warbird looks with mild-mannered sport airplane flying characteristics.
• Preinstalled 8cc Evolution gas engine.
• SAFE technology with panic recovery integrated in factory-installed
• Spirted flight performance for experienced pilots.
• Wide landing gear stance for excellent ground handling.
• Throttle pushrod needed adjustment.
AT A GLANCE ...
motor after my first trip to the flying
field, I found that to get full throttle
and a reliable idle, the endpoints on my
throttle were at 43/120. In technical
terms, that’s out to lunch! Because the
43 was on the low end, the servo was
pulling the pushrod too far backward.
With a Z-bend on the servo end, there’s
no adjustment available.
I removed the servo screw and offset
the servo arm one tooth toward full
throttle and tried again. This gave me
mid-70s for both endpoints and a nice
linear throttle response. I used a Hangar
9 inline amp meter to measure the servo
current, and to adjust the endpoints for
full throttle and fully closed without
binding the servo and drawing excess
I mixed some ethanol-free gas with
Red Line two-stroke oil. The Evolution
engine calls for a 20: 1 ratio, which is
twice what I normally run, and I had to
employ a different gas can.
The engine refused to fire until the
throttle stick was at approximately
half throttle, so I performed the fix as
detailed in the construction section of
this article. When the throttle pushrod
was squared away, the engine ran nicely
on the bench and didn’t need any
tuning. After a few minutes, I headed
out for my first flight.
The Mustang’s wide stance and
forward-facing gear do their job on the
in advanced mode
and pushed the
and straight and
broke ground at
half throttle after
feet. I noted that
the trim needed
some right aileron
and up-elevator, so
I landed and made
on the control
surfaces. Up into
the air again, the
well and was
stable. It was time
to play with the
move the control
stick, the airplane
will only achieve
a bank angle of
25° or so. It will
but even at full
unless you chop the throttle.
I found it difficult to fly in this mode.
The turn radius required to get the
Mustang to come back is quite wide. If
you let go of the stick, the airplane levels
out and does a slight climb. Someone
trying to get the hang of the perceived
control reversal needs to merely let go
and the airplane will right itself until he
or she can regain control.
This felt more comfortable, and as an
instructor, this would likely be the mode
in which I would encourage my students
to start out flying. Banking is limited
to roughly 45° with more elevator
It still doesn’t allow inverted flight,
but control response felt better and the
turn radius was improved. Stabilization,
even in the wind, felt good and the
SAFE system could inspire confidence in
a new pilot.
Although stabilization is still active in
advanced mode, the SAFE system allows
the pilot to have full control. Loops,
rolls, and inverted flight are all possible.
Full-throttle passes are fairly quick and,
as a sport airplane, this is a lot of fun.
I noticed some oscillation in the
ailerons when flying at full speed,
which indicates too much gyro gain.
I downloaded the AS3X app to my
smartphone and ordered a cable to allow
me to reduce the gain on each axis.
Dropping the gain by 5% on the aileron
axis took care of the issue.
I took the Mustang up high enough
that I had enough room for a mistake
from the gyro and a mistake by me.
The instructions indicate that sufficient
altitude is needed to allow the airplane
No matter what attitude I had the
Mustang in—upside down, straight up,
straight down, or in a spin—as soon as
I released the controls and pressed the
panic button, the airplane leveled off
and started a slight climb. This will give
pilots enough time to take a breath if
they get in trouble, and allow them to
settle down and start flying again.
Landing is easily accomplished by
68 Model Aviation MARCH 2016 www.ModelAviation.com