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The Zenoah GT-80 provides plenty of power for all but the most aggressive
vertical maneuvers. The plane can pull itself out of a hover, but it requires
a bit of patience. Im sure if I had taken the time to properly tune
the engine for my altitude and experimented with different props, I would
have found its vertical performance to be even better. As it stands, I
am very pleased with the power-to-weight ratio of this combination.
TAKEOFF AND LANDING Whenever I test-fly a high-performance model such
as this, I triple-check every nut, bolt, control throw, hinge and the
center of gravity, but I found that as usual, John Reid had done a superb
job of putting this beast together. After a few taxi trips down the runway
and back, I checked the wind and the pattern and rolled on the throttle.
The big Extra tracked very true and stayed right on the centerline with
just a little pressure on right rudder. As soon as the wheels left the
ground, I knew that I would have a hard time giving the radio back to
its rightful owner!
Landing this plane is simple because its a bit of a floater. My
first approach was slightly high, so I decided to abort. Im always
careful to ease into the throttle with these big gassers, particularly
when Im low and slow. The second approach was much better, and I
managed a pretty good 3-point landing. Subsequent landings proved to be
equally easy. The key is to fly a shallow approach with a few clicks of
throttle. When the Extra reaches the runways threshold, I chop the
throttle to idle and carefully add up-elevator until the wheels touch
down.
LOW-SPEED PERFORMANCE In my mind, there are two modes of low-speed flight
for a plane like this: 3D and normal. In normal flight attitudes, this
Extra gives noticeable warning before it enters a hard stall. The flight
controls start to become mushy, and you certainly can tell
that it wants some power so it can fly normally again. If the envelope
is pushed and a stall is forced, the Extra will drop its nose and porpoise
until power is added or altitude is traded for airspeed.
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In 3D/High Alpha flight, the Extra maintains positive control throughout
the entire flight envelope with proper use of high-rate throws and throttle
management. The JR 8411 digital servos provide excellent response, and
the limiting factor is definitely my own reaction timenot the servos.
Elevators are very stable, and harriers dont even require full throw
on high rates. High Alpha knife-edge, rolling harriers, waterfallsquite
simply, every 3D maneuver that I know how to doare all easily within
the capabilities of this plane. With the GT-80 and the Zinger prop, I
was able to easily hover at a tick below 1/2 throttle. Torque rolls are
slow and graceful, and once the sweet spot was found (for me, this was
almost perfectly vertical with a hint of right rudder and a touch of up-elevator),
only small corrections were required to keep going around and around.
I have never professed to be a master of aerobatic or 3D flight, but this
plane makes me look good!
HIGH-SPEED PERFORMANCE Although low-speed performance can be coupled with
3D aerobatics, I like to separate high-speed performance from traditional
aerobatics simply because there is a whole class of large planes that
is dedicated to speed but is not intended to perform aerobatics competitively.
The Zenoah GT-80 will definitely haul this plane around at a very high
rate of speed, but I wouldnt recommend flying it at full throttle
unless it is in a vertical upline. As with any large plane, throttle management
is critical. Never fly downlines with anything more than one or two clicks
of throttle, if that. The Extra is an easy-to-fly aerobat, but you must
pay constant attention to the throttle.
AEROBATICS Aerobatic performance is where the Extra lives and what it
was designed to do. It is an extremely neutral-flying plane; each individual
control surface has very little impact on the others. For example, in
straight knife-edge flight, absolutely no roll correction is required,
and I noted only a touch of coupling toward the belly. Flat turns are
done almost purely with rudder, with just a hint of elevator correction
needed. Point rolls are exceptional; rolls are axial. With the proper
application of a little elevator and rudder at the appropriate times,
even slow rolls are a cinch. One of my favorite maneuvers is a very slow
flat spin, which I was able to do on low rates at idle. It is quite graceful
and easy to fly away from by adding throttle while neutralizing the rudder
and aileron and easing off the elevator until airspeed is gained. Snap
rolls are very clean and precise, but they require a bit more finesse
with the Extra than with most smaller aerobatic planes. In the flight
tips section at the end of the construction manual, Mike McConville gives
the best advice for snaps: start a snap roll normally, but as soon as
the sticks reach the corners, neutralize the elevator to prevent losing
too much airspeed and getting too deep into the maneuver.
For pilots who want to compete in IMAC on a serious level or for weekend
warriors who want to polish their repertoire, the 33% Hangar 9 Extra 330S
is the plane that can get it done with style.
Jet Thompson
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