The Valiant is designed to accept the Evolution
33GX engine shown here. Mounted inverted, the
engine is a great match for this airplane.
Each of the wing panels is a plug-in design,
sliding on an aluminum tube and held in via a
single 1/4-20 nylon bolt.
Also included with the review model was an Evolution
wraparound muffler. I had to cut away a small corner around
the firewall to allow for the muffler clearance, but other than
that, it fit nicely.
The fuel tank, fuel line, and hardware are then fitted to the
fuselage. There is no specific spot indicating where the fuel
dot filler mounts, so I left that until after the cowl was fitted.
I always like to install the Smart-Fly Ignition Cutoff in my
gasoline aircraft. This system allows me to remotely kill the
engine and I usually set it up to utilize the trainer button on
my DX18 transmitter.
The cowl was next on the list. This is the only step where a
bit of modeling comes into play. If you’re using a gas engine,
the manual recommends that a baffle be cut and glued inside
the cowling. This baffle will direct airflow over the engine’s
fins to help with cooling.
A template is provided on the inside back page of the
manual. Using the template, the baffle is
cut out from thick cardstock, and then
epoxied into position. I had to work
with it to get the baffle to fit snugly, yet
allow the cowl to be removed. When I
was satisfied with everything, and had
double-checked the measurements, I
glued it in with 30-minute epoxy and
After the wheels and wheel pants
were installed on the aluminum main
gear, the gear was bolted into position
underneath the fuselage. The predrilled
holes have T-nuts installed, so this is
simple. Don’t forget to use a dab of
To complete the fuselage assembly,
the side and front windows were glued
into place. When the glue cured, the
Valiant was finished. The completed
model weighs 15. 5 pounds—lighter
than the manual specified! It was slightly
nose-heavy, so I repositioned the ignition
battery and that solved the problem.
Working on the model a couple of
hours a night, it took approximately
three days to assemble—roughly 7 hours
Assembling the Valiant at the field
is fast, even if you transport it without
the tail surfaces attached. The fuselage is quite nose-heavy
without the tail attached, so be sure to secure it properly in
your vehicle. When the bolts and clevises are attached, the
wings slide on and each attaches with a single thumbscrew.
Attach the top hatch, fuel the model, and it’s ready to go.
When it came time to start the Evolution 33 engine, I had
no luck with hand starting, but I had brought my electric
start, just in case. Within just a few seconds of using the
starter, the engine came to life. After the engine is broken in,
hand starting will probably work, but it is not a big deal to
use the starter.
After checking the controls, I taxied out to the runway. My
field has some grass between the pit area and the runway. It’s
not the smoothest, but the Valiant had no problem with the
little bumps. When it came time to line up on the runway, I
found that I would have liked more rudder because the long
fuselage makes for a wide turn.
57 Model Aviation APRIL 2015 www.ModelAviation.com