50 MODEL AVIATION
IF YOU’RE THROUGH throwing your
transmitter’s control sticks around
haphazardly and looking for an aircraft that
will help you hone your skills as a proficient
RC pilot (as apposed to mostly lucky),
you’re in the market for an RC Aerobatics
(Pattern) airplane. Because Pattern models
are designed to perform challenging
maneuvers gracefully, they have been
known to “make the pilot look good,” as it
has been put.
If there’s a “Pattern” pilot at you’re field,
perhaps you’ve taken the time to appreciate
that style of flying. The giant loops, slow
rolls that go from one end of the field to the
other, and snaps that start and finish crisply
from the same heading are beautiful, as they
should be; a proficient pilot
practices regularly.
If you enjoy how well these
people fly, be sure to let them know; they’ll
appreciate it. If you talk with these pilots for
a while, you might decide that flying
precision Aerobatics is your next step.
In any case, the Hangar 9 ShowTime 4D
from Horizon Hobby has all the goods of a
Pattern model, but it is also capable of being
a fantastic-tumbling 3-D aerobatics
performer. This model is appropriately sized
for those who don’t want to make the
obligation to plunge into a large 2-meterclass
Pattern aircraft but want the full flavor
of flying with grace and precision.
A number of the ShowTime’s key
Plane Talk: Hangar 9 ShowTime 4D 90 ARF
MICHAEL RAMSEY
Stabilizer halves are supported with an
anodized aluminum spar tube and located
with aluminum pins at the root. Elevator
linkage uses snap-on ball links.
Wing halves plug into the fuselage and are
drawn tight with 1/4-20 nylon thumbscrews.
All the parts are prealigned at the factory.
The recommended CG is spot-on for the author. Almost no down-stick pressure is
required to maintain an inverted cruise.
Even at half throttle
this model requires
little top rudder to
maintain a heading.
Almost no cross
control mixing is
needed.
An ARF sport model with the grace
of a Pattern airplane and the outof-
this-world performance of a
Freestyle model
10sig2.QXD 8/24/06 9:22 AM Page 50October 2006 51
The generous hatch size makes servicing
equipment easy. A six-cell, 1400 mAh
battery under the fuel tank brought the
CG to the exact location.
The Tru-Turn 21/2-inch spinner was finished with UltraCote Paint. There’s enough
propeller clearance to suit any choice of power plant.
The generous rudder needs a powerful servo such as the JR 8411SA for guidance. The
carbon-fiber tail wheel is a symbol of the high-quality hardware included.
Looking down the fuselage into the tail
reveals the molded sheeting in the bottom
corners. The reversing Y harness’s long
leads reached the elevator servos.
The Side Force Generators plug in and are
secured with a red (so you can find it in the
grass) thumbscrew. Knife-edge performance
is greatly enhanced with these installed.
The four-color UltraCote trim scheme offers a strong contrast between the model’s top
and bottom. The fuel tank comes plumbed and ready to install.
Photos by Mark Lanterman and the author
10sig2.QXD 8/24/06 9:25 AM Page 5152 MODEL AVIATION
• Brittle tail-wheel linkage springs
Pluses and Minuses
+
-
Test-Model Details
Engine used: Saito 1.00 four-stroke
Propeller: APC 14 x 8 (break-in), 15
x 4W (flying)
Fuel: 600cc (approximately 14
ounces) tank, Magnum #1
Radio system: JR 6102 transmitter,
JR 770S receiver, four JRPS9411
servos, one JRPS8411SA servo, one
JRPS537 servo, JR 1500 mAh 6.0-volt
battery, ElectroDynamics Pro Servo
Reverser Y, four 9-inch servo
extensions
Ready-to-fly weight: 8.69 pounds
Flight duration: Exceeds 10 minutes
Specifications
Type: RC sport aerobatic ARF
Pilot skill level: Advanced
Wingspan: 66 inches
Wing area: 900 square inches
Length: 68.3 inches
Weight: 8-9 pounds
Wing loading (average): 21.76
ounces per square foot
Engine: .61-1.00 (two-stroke) or .91-
1.10 (four-stroke) glow
Radio: Six channels (minimum), six
heavy-duty servos
Construction: All-wood airframe;
fiberglass wingtips, cowl, and wheel
pants; carbon-fiber landing gear; clear
smoked canopy
Covering/finish: Four-color genuine
UltraCote-film trim scheme, matching
fuelproof paint on landing gear,
cowling, canopy, wheel pants
Price: $199.99
• Fast assembly thanks to excellent
parts fit
• A+ hardware and accessory
package
• Flies like a dream
Saito FA-100 Engine
Four-stroke engines have been out long
enough that there’s nothing to be afraid
about when it comes to running and tuning
them. It’s true that a two-stroke engine has
fewer parts and is simpler to operate to
some extent, but the modern four-stroke is
a thing of beauty that produces gobs of
power.
The Saito FA-100 is worth seriously
considering if you have a 60-size model
that needs an engine. Compared with the
similarly displaced .91 Saito and same size
engines in competition, it will turn the
same 14 x 8 APC propeller 300-700 rpm
faster under the same conditions
(atmosphere, fuel, plug, etc.). Refinements
of the FA-100 even permitted the Saito
engineers to make it approximately 2
ounces lighter than most other .91 fourstrokes.
Don’t be afraid to mount the Saito
inverted. Forget the rumors you might have
heard about getting an engine to idle this
way. All it took with the ShowTime 4D
was low-speed needle tweaking and the
fuel metered perfectly for an all-day idle at
2,000 rpm (with no glow heat). Throttle
transition from these long idles is
immediate; slam the throttle stick to full
and the engine doesn’t cough, spit, or
stutter.
Nothing builds confidence in a new
airplane like the feeling you get when you
know the engine is reliable. The Saito FA-
100 required only a minimal run-in period
before it could be flown, and that was
done with the engine mounted in the
airplane just before the first flight.
Out of the box the engine showed no
bad habits. To get the idle right, the lowspeed
needle was leaned roughly 11/2 turns
from the flush factory setting. It’s not
unusual to excessively lean the low-end
adjustment, especially with an inverted
engine.
The ShowTime was first flown with an
APC 14 x 6 propeller with the Saito tuned
roughly 1/4 turn rich (this propeller is
smaller than recommended). The extra
fuel kept the engine cool even though it
was turning a high rpm (approximately
9,000).
For the next couple flights the engine
was leaned further but not peaked. After
the sixth flight the engine graduated to an
APC 14 x 8 propeller and was flown with
an optimal high-speed needle setting.
For fun-flying, a longer-diameter/
smaller-pitch propeller combination will
limit the top-end flight speed while
increasing the throttle response. For
hoverbatics, 3-D, and now 4-D flight,
you want as much thrust (air) rushing
over the control surfaces as possible to
improve their effectiveness. The next
step is to give the APC 15 x 4W
propeller a try. The engine “bump” starts
typically, and the starter is only needed
on the first flight of the day.
The Saito FA-100 is a clean-running
engine with a fuel system that is easy to set
up and tune. After roughly two hours of
flight time, the valves will be checked and
adjusted as needed. Tools and instructions
for this job are provided, making the short
maintenance task easy. MA
—Michael Ramsey
FA-100 Specifications
Type: Four-stroke
Displacement: 1.10 cu. in. (17.10 cc)
Bore: 1.14 inches (29.0 mm)
Stroke: 1.02 inches (26.0 mm)
Cylinder: Single—chrome plated (AAC)
Total weight: 20.9 ounces
Crankshaft threads: 8 x 1.25mm
Propeller range: 13 x 9-14 x 10
Rpm range: 2,000-11,000
Horsepower: 1.8
features illustrate its versatility. The fuselage
is stretched out long so the maneuvers it
draws through the air look smooth. The wing
and tail surfaces are fully symmetrical for
equal handling in upright and inverted
flying. The thicker tail surfaces also improve
their strength.
All movable control surfaces are
oversized, with hinge joints that are double
beveled to allow for an extreme rate of
control-surface deflection. For Pattern and
otherwise normal flying, only small amounts
of control throw are necessary. When a pilot
wants to fly in a more outrageous manner,
maximum control throw is available with
just the flick of a dual-rate switch, to help
with whatever stunts might be desired.
The ShowTime 4D is the best of both
worlds. It’s a Pattern model and a Freestyle
airplane, but the correct engine and radioaccessory
choices are essential to optimize
the performance potential.
Because of its lightweight airframe, this
model can be flown with a strong .61 twostroke
engine. However, it will do just that:
fly around, struggling with any maneuver
that requires climb performance. The .91-
1.10 class of two- and four-stroke glow
engines are excellent choices for the
ShowTime.
Although not recommended, the new
Saito 1.25 would make an excellent engine
The Saito FA-100 fit perfectly into the
included mounting beams attached to
the preinstalled blind nuts behind the
6mm firewall.
10sig2.QXD 8/24/06 9:26 AM Page 52choice for the Masters or FAI class
competitor who is looking for a smaller
practice model. The larger engine would
give the ShowTime an extra boost of power
for long vertical lines containing snap and
rolling maneuvers along the way.
However, power management would be
essential to flying this model in an
overpowered condition. Large control
surfaces and high-speed flight take their toll
on an airframe, especially when flutter is
induced. Unless you’re willing to take the
risk, stick with the recommended engine
recommendations. Regardless, good throttle
management is a sensible practice.
The servos recommended by the
manufacturer are the best available on the
market. To fully experience the ShowTime’s
capabilities, I don’t recommend deviating
from the servo-output requirements.
With any RC model, how good the
servos are will determine how well the
model can be controlled. That point is more
evident in the ShowTime because of the
oversized control surfaces and high rate of
deflection.
Although it’s basically a .60-size
model—where 50 inch-ounce power servos
might typically work fine—the ShowTime is
special. Powerful and silky-smooth-moving
servos will make a distinct difference in how
this model flies.
I used the recommended digital servos
and experienced excellent results. If I werebudget-conscious, one option might be to
choose similar-power-output servos that
weren’t digital but at least had a coreless
motor drive.
The ShowTime is an excellent candidate
for electric-power conversion. The weight
distribution and servo-location options
make this model an ideal choice.
The large cockpit hatch makes servicing
convenient, so getting a power pack in and
out of the model would be a nonissue.
You’d want at least a 900- to 1,500-watt
power system. The stock carbon-fiber
landing gear is long enough to support up to
an 18-inch propeller, so either a direct drive
or gearbox system could be operated.
ShowTime on the Bench: Assembling this
model was the most fun I’ve had putting an
ARF together in sometime. Quality
construction and engineering had a lot to do
with that.
I liked that critical areas of alignment
were already prepared at the factory. The
vertical fin was built into the fuselage, so it
arrived as straight as it was ever going to be.
The stabilizer and elevators were provided
as mirror assemblies that plugged into the
tail section using aluminum tube spars and
alignment pins through fiberglass sockets
built into the fuselage. Everything was
aligned, so I just bolted it on.
The wings attached in roughly the same
way as the stabilizers. But instead of
machine screws through the outer surface,
1/4-20 nylon thumbscrews threaded through
the fuselage sides into each wing root,
keeping them tight against the framework.
Alignment between the wing and stabilizer
was accurate within 1/16 inch, which are
satisfactory tolerances.
The only glues needed to complete the
assembly were cyanoacrylate for the hinges
and RC/56 for the canopy. The only
deviation I made from the entire instruction
manual was to mount the prepainted canopy
with 4-40 nylon screws. Now I can touch up
the covering or add a pilot figure whenever
I’m ready.
The hardware package included with the
Showtime was exceptional. Weightwise, the
8-32 hardware was overkill, but it was a fair
trade when also included were slop-free ball
links and steel-bearing-supported clevises.
I never thought the term “spared no
expense” could be used when it came to
included ARF hardware, but I commend
Hangar 9 for this offering. From the carbonfiber
tail-wheel, to the socket-head screws,
to the rubber wheels and preassembled
seamless fuel tank, all of it was first-class.
I usually dread engine installation
because it’s a custom job that requires a
great deal of measuring, then measuring
again, with guessing mixed in, sprinkled
with patience and craftsmanship.
Mounting the engine in this model was a
breeze, owing to choosing one of the
recommended power options: the Saito
1.00. The predrilled firewall and detailed
instructions in the illustrated manual were
well ordered and helpful.Fitting the cowl was easy too because its
mounting holes were already drilled and
aligned with the 4-40 blind nuts in the
fuselage. As I pointed out, the manual was
well detailed and explained expert methods
for sizing and locating cutouts in the cowl to
accept the muffler, cylinder head, and
cooling exits.
To get the cowl to align perfectly with the
21/2-inch Tru-Turn spinner, I had only to
make the mounting holes slightly oblong on
the right side. That’s nothing a #4 washer
can’t hide.
Even though the best option is to spend
the extra money on the high-tech digital
servos, it doesn’t mean the pilot needs a
$1,000 transmitter to go along with it. The
JR 6102 radio is more than adequate to fly
the ShowTime with expert results.
To mix the dual elevator servos I used a
servo-reversing Y harness from
ElectroDynamics. This accessory was
especially handy because its heavy-duty
leads were just long enough to reach the tailmounted
servos.
I saved the rudder installation as the last
step after finding out how close the model
was to balancing around the recommended
CG. The flight pack and rudder servo were
my two ballast devices, and as it worked out
the battery found its home under the fuel
tank when the rudder servo was mounted
between the wings and connected with the
provided pull-pull cable system.
The ShowTime’s airframe was so
minimal that where to locate the power
switch was a tough choice. A miniswitch
would fit in the fuselage cutout provided, but
the heavy-duty JR switch wouldn’t. In
addition, I wanted the switch on the opposite
side from the exhaust.
I ended up making a cutout in the
fuselage against the aft edge of the former,
behind the fuel tank and hidden under the
wing LE.
The control-surface setup and radio
programming was a simple procedure. The
pushrods were provided at the correct length
and machined with right-hand threads on one
end and left-hand threads on the other.
The benefit of being able to fine-tune
these mechanical linkages is that the finished
pushrod assembly can be adjusted to a length
between half turns of the linkages. Extreme
control throws and large surfaces amplify the
slightest misalignments in the linkage
geometry. Experts in flying precision
aerobatics pay top dollar for accessories with
this feature.
Following the recommended mechanical
linkage setup in the book, full throw on the
channel’s travel volume control would
provide the recommended high rate
deflections. For my taste, 50%-75%
exponential was programmed into the high
rates.
To get the recommended low rates
required lowering the control-surface
deflections to 20%. Doing this diluted the
fidelity of the control-surface movement, but
the precision of the JR digital servos helps
make up for reduction in resolution. No
exponential was programmed into the low
rates.
The location of the Side Force Generators
(SFGs) did not affect the CG. Built up from
hard-balsa stock, they were rigid and easy to
install. Their purpose is to improve lateral
stability, knife-edge flight performance, and
rudder-input authority. They dramatically
change the looks of the model from the
profile view, but for the most part they don’t
affect recognition or orientation.
Flying: The ShowTime is as long as most
1/4-scale models I’ve owned, but it is
significantly easier to transport. By removing
the stabilizer halves and wing panels, the
long fuselage slides easily between the trunk
and fold-down seats of my Honda. It all bolts
back together with standard socket-head
bolts and thumb screws.
Because of the oversized tail wheel, the
ShowTime rests close to level on the ground.
As a result, the takeoff rotation is subtle. The
Saito 1.00 provides plenty of power for
liftoff at approximately the half-stick
position on the throttle. Climbout
performance is respectable, with only
roughly half throttle as well.
Overall, the ShowTime proved to be a
groovy airplane. Minor trim adjustments
were made to the controls; the model
basically flew right off the bench.
Level cruise can actually be performedquite slowly; only full power is needed to
drive the ShowTime upstairs. Climbout is
easy to resume from rolls and snaps on the
up-line. On the down-line, some elevator
down-trim is needed to hold the straight
line.
The recommended low rates felt
adequate for normal flying except in the
stall turns. The fix there for me was to
increase only the rudder low rate and add
approximately 30% exponential.
As a testimony to the accurate CG
placement, rolling maneuvers require almost
no rudder or elevator input to maintain
altitude and heading. (I’m sure the SFGs
help here too.) Inverted flight needs just a
breath of elevator to maintain level flight or
45° lines.
Knife-edge flight is easy with the
ShowTime. Experienced pilots will have to
“forget” about adding rudder while doing
point rolls. At slow speeds, increased rudder
input has only a minimal proverse roll
effect. Mixing can correct that or a pilot can
cross control the aileron input as needed.
Knife-edge loops? You got ’em! As big
or as small as you like.
High rate control with the heavy dose of
exponential is easy with which to get
comfortable. Almost the only warning I can
give you is to manage elevator input
carefully and watch for tip-stalling.
The ShowTime eventually reaches an
angle of attack and power setting where a
stall is unavoidable. The trick is to rescue
the model from the stall by adding power—
not more elevator. Mixing reflex into the
aileron controls will reduce tip-stalling.
Roughly 8° of input is all that is required to
keep the wings from “wagging” while flying
in a high-alpha condition.
I could do Waterfalls all day long with
the ShowTime. It tracks straight through the
maneuver, and almost no torque correction
is required during power application. It
didn’t take me long to bring the outside
Waterfall entry lower and lower to the
ground. I just knew that it would come
around, wings level and happy to do
another.
Okay, so the SFGs work great. Why
should they ever be removed, and how does
the ShowTime fly without them?
Almost the only time the SFGs were a
handicap was when flying in high winds—
particularly when they were cross. All that
extra side area worked like a sail on a
sailboat that doesn’t have a center board.
The model gets pushed, and to fly straight
requires a strong crab angle. The added drag
of the crab angle reduces the effective
power from the engine, which leads to poor
vertical performance.
When I flew without the SFGs,
penetration was improved in high winds.
The absence of the SFGs was noticeable
when it came to 3-D agility. It requires only
minutes to put them on or take them off,
which is a great option.
The ShowTime has a nice glide slope. Its
slippery lines improve the glide
performance, as does the light wing loadingFull-stall landings show no sign of tipstalling.
It’s easy to touch the tail wheel
before the main wheels. Don’t worry; the
carbon-fiber tail bracket can take it.
The ShowTime’s handling qualities are what
some would describe as “honest.” It goes
where you point it, with almost no adverse
reactions or coupling.
Mike McConville designed an excellent
model. The ability to perform a diverse list of
maneuvers excellently makes it a great
aerobatic model for any RC pilots who are
looking for an easy-to-assemble airplane that
will show them the ropes. MA
Michael Ramsey
Edition: Model Aviation - 2006/10
Page Numbers: 50,51,52,54,56
Edition: Model Aviation - 2006/10
Page Numbers: 50,51,52,54,56
50 MODEL AVIATION
IF YOU’RE THROUGH throwing your
transmitter’s control sticks around
haphazardly and looking for an aircraft that
will help you hone your skills as a proficient
RC pilot (as apposed to mostly lucky),
you’re in the market for an RC Aerobatics
(Pattern) airplane. Because Pattern models
are designed to perform challenging
maneuvers gracefully, they have been
known to “make the pilot look good,” as it
has been put.
If there’s a “Pattern” pilot at you’re field,
perhaps you’ve taken the time to appreciate
that style of flying. The giant loops, slow
rolls that go from one end of the field to the
other, and snaps that start and finish crisply
from the same heading are beautiful, as they
should be; a proficient pilot
practices regularly.
If you enjoy how well these
people fly, be sure to let them know; they’ll
appreciate it. If you talk with these pilots for
a while, you might decide that flying
precision Aerobatics is your next step.
In any case, the Hangar 9 ShowTime 4D
from Horizon Hobby has all the goods of a
Pattern model, but it is also capable of being
a fantastic-tumbling 3-D aerobatics
performer. This model is appropriately sized
for those who don’t want to make the
obligation to plunge into a large 2-meterclass
Pattern aircraft but want the full flavor
of flying with grace and precision.
A number of the ShowTime’s key
Plane Talk: Hangar 9 ShowTime 4D 90 ARF
MICHAEL RAMSEY
Stabilizer halves are supported with an
anodized aluminum spar tube and located
with aluminum pins at the root. Elevator
linkage uses snap-on ball links.
Wing halves plug into the fuselage and are
drawn tight with 1/4-20 nylon thumbscrews.
All the parts are prealigned at the factory.
The recommended CG is spot-on for the author. Almost no down-stick pressure is
required to maintain an inverted cruise.
Even at half throttle
this model requires
little top rudder to
maintain a heading.
Almost no cross
control mixing is
needed.
An ARF sport model with the grace
of a Pattern airplane and the outof-
this-world performance of a
Freestyle model
10sig2.QXD 8/24/06 9:22 AM Page 50October 2006 51
The generous hatch size makes servicing
equipment easy. A six-cell, 1400 mAh
battery under the fuel tank brought the
CG to the exact location.
The Tru-Turn 21/2-inch spinner was finished with UltraCote Paint. There’s enough
propeller clearance to suit any choice of power plant.
The generous rudder needs a powerful servo such as the JR 8411SA for guidance. The
carbon-fiber tail wheel is a symbol of the high-quality hardware included.
Looking down the fuselage into the tail
reveals the molded sheeting in the bottom
corners. The reversing Y harness’s long
leads reached the elevator servos.
The Side Force Generators plug in and are
secured with a red (so you can find it in the
grass) thumbscrew. Knife-edge performance
is greatly enhanced with these installed.
The four-color UltraCote trim scheme offers a strong contrast between the model’s top
and bottom. The fuel tank comes plumbed and ready to install.
Photos by Mark Lanterman and the author
10sig2.QXD 8/24/06 9:25 AM Page 5152 MODEL AVIATION
• Brittle tail-wheel linkage springs
Pluses and Minuses
+
-
Test-Model Details
Engine used: Saito 1.00 four-stroke
Propeller: APC 14 x 8 (break-in), 15
x 4W (flying)
Fuel: 600cc (approximately 14
ounces) tank, Magnum #1
Radio system: JR 6102 transmitter,
JR 770S receiver, four JRPS9411
servos, one JRPS8411SA servo, one
JRPS537 servo, JR 1500 mAh 6.0-volt
battery, ElectroDynamics Pro Servo
Reverser Y, four 9-inch servo
extensions
Ready-to-fly weight: 8.69 pounds
Flight duration: Exceeds 10 minutes
Specifications
Type: RC sport aerobatic ARF
Pilot skill level: Advanced
Wingspan: 66 inches
Wing area: 900 square inches
Length: 68.3 inches
Weight: 8-9 pounds
Wing loading (average): 21.76
ounces per square foot
Engine: .61-1.00 (two-stroke) or .91-
1.10 (four-stroke) glow
Radio: Six channels (minimum), six
heavy-duty servos
Construction: All-wood airframe;
fiberglass wingtips, cowl, and wheel
pants; carbon-fiber landing gear; clear
smoked canopy
Covering/finish: Four-color genuine
UltraCote-film trim scheme, matching
fuelproof paint on landing gear,
cowling, canopy, wheel pants
Price: $199.99
• Fast assembly thanks to excellent
parts fit
• A+ hardware and accessory
package
• Flies like a dream
Saito FA-100 Engine
Four-stroke engines have been out long
enough that there’s nothing to be afraid
about when it comes to running and tuning
them. It’s true that a two-stroke engine has
fewer parts and is simpler to operate to
some extent, but the modern four-stroke is
a thing of beauty that produces gobs of
power.
The Saito FA-100 is worth seriously
considering if you have a 60-size model
that needs an engine. Compared with the
similarly displaced .91 Saito and same size
engines in competition, it will turn the
same 14 x 8 APC propeller 300-700 rpm
faster under the same conditions
(atmosphere, fuel, plug, etc.). Refinements
of the FA-100 even permitted the Saito
engineers to make it approximately 2
ounces lighter than most other .91 fourstrokes.
Don’t be afraid to mount the Saito
inverted. Forget the rumors you might have
heard about getting an engine to idle this
way. All it took with the ShowTime 4D
was low-speed needle tweaking and the
fuel metered perfectly for an all-day idle at
2,000 rpm (with no glow heat). Throttle
transition from these long idles is
immediate; slam the throttle stick to full
and the engine doesn’t cough, spit, or
stutter.
Nothing builds confidence in a new
airplane like the feeling you get when you
know the engine is reliable. The Saito FA-
100 required only a minimal run-in period
before it could be flown, and that was
done with the engine mounted in the
airplane just before the first flight.
Out of the box the engine showed no
bad habits. To get the idle right, the lowspeed
needle was leaned roughly 11/2 turns
from the flush factory setting. It’s not
unusual to excessively lean the low-end
adjustment, especially with an inverted
engine.
The ShowTime was first flown with an
APC 14 x 6 propeller with the Saito tuned
roughly 1/4 turn rich (this propeller is
smaller than recommended). The extra
fuel kept the engine cool even though it
was turning a high rpm (approximately
9,000).
For the next couple flights the engine
was leaned further but not peaked. After
the sixth flight the engine graduated to an
APC 14 x 8 propeller and was flown with
an optimal high-speed needle setting.
For fun-flying, a longer-diameter/
smaller-pitch propeller combination will
limit the top-end flight speed while
increasing the throttle response. For
hoverbatics, 3-D, and now 4-D flight,
you want as much thrust (air) rushing
over the control surfaces as possible to
improve their effectiveness. The next
step is to give the APC 15 x 4W
propeller a try. The engine “bump” starts
typically, and the starter is only needed
on the first flight of the day.
The Saito FA-100 is a clean-running
engine with a fuel system that is easy to set
up and tune. After roughly two hours of
flight time, the valves will be checked and
adjusted as needed. Tools and instructions
for this job are provided, making the short
maintenance task easy. MA
—Michael Ramsey
FA-100 Specifications
Type: Four-stroke
Displacement: 1.10 cu. in. (17.10 cc)
Bore: 1.14 inches (29.0 mm)
Stroke: 1.02 inches (26.0 mm)
Cylinder: Single—chrome plated (AAC)
Total weight: 20.9 ounces
Crankshaft threads: 8 x 1.25mm
Propeller range: 13 x 9-14 x 10
Rpm range: 2,000-11,000
Horsepower: 1.8
features illustrate its versatility. The fuselage
is stretched out long so the maneuvers it
draws through the air look smooth. The wing
and tail surfaces are fully symmetrical for
equal handling in upright and inverted
flying. The thicker tail surfaces also improve
their strength.
All movable control surfaces are
oversized, with hinge joints that are double
beveled to allow for an extreme rate of
control-surface deflection. For Pattern and
otherwise normal flying, only small amounts
of control throw are necessary. When a pilot
wants to fly in a more outrageous manner,
maximum control throw is available with
just the flick of a dual-rate switch, to help
with whatever stunts might be desired.
The ShowTime 4D is the best of both
worlds. It’s a Pattern model and a Freestyle
airplane, but the correct engine and radioaccessory
choices are essential to optimize
the performance potential.
Because of its lightweight airframe, this
model can be flown with a strong .61 twostroke
engine. However, it will do just that:
fly around, struggling with any maneuver
that requires climb performance. The .91-
1.10 class of two- and four-stroke glow
engines are excellent choices for the
ShowTime.
Although not recommended, the new
Saito 1.25 would make an excellent engine
The Saito FA-100 fit perfectly into the
included mounting beams attached to
the preinstalled blind nuts behind the
6mm firewall.
10sig2.QXD 8/24/06 9:26 AM Page 52choice for the Masters or FAI class
competitor who is looking for a smaller
practice model. The larger engine would
give the ShowTime an extra boost of power
for long vertical lines containing snap and
rolling maneuvers along the way.
However, power management would be
essential to flying this model in an
overpowered condition. Large control
surfaces and high-speed flight take their toll
on an airframe, especially when flutter is
induced. Unless you’re willing to take the
risk, stick with the recommended engine
recommendations. Regardless, good throttle
management is a sensible practice.
The servos recommended by the
manufacturer are the best available on the
market. To fully experience the ShowTime’s
capabilities, I don’t recommend deviating
from the servo-output requirements.
With any RC model, how good the
servos are will determine how well the
model can be controlled. That point is more
evident in the ShowTime because of the
oversized control surfaces and high rate of
deflection.
Although it’s basically a .60-size
model—where 50 inch-ounce power servos
might typically work fine—the ShowTime is
special. Powerful and silky-smooth-moving
servos will make a distinct difference in how
this model flies.
I used the recommended digital servos
and experienced excellent results. If I werebudget-conscious, one option might be to
choose similar-power-output servos that
weren’t digital but at least had a coreless
motor drive.
The ShowTime is an excellent candidate
for electric-power conversion. The weight
distribution and servo-location options
make this model an ideal choice.
The large cockpit hatch makes servicing
convenient, so getting a power pack in and
out of the model would be a nonissue.
You’d want at least a 900- to 1,500-watt
power system. The stock carbon-fiber
landing gear is long enough to support up to
an 18-inch propeller, so either a direct drive
or gearbox system could be operated.
ShowTime on the Bench: Assembling this
model was the most fun I’ve had putting an
ARF together in sometime. Quality
construction and engineering had a lot to do
with that.
I liked that critical areas of alignment
were already prepared at the factory. The
vertical fin was built into the fuselage, so it
arrived as straight as it was ever going to be.
The stabilizer and elevators were provided
as mirror assemblies that plugged into the
tail section using aluminum tube spars and
alignment pins through fiberglass sockets
built into the fuselage. Everything was
aligned, so I just bolted it on.
The wings attached in roughly the same
way as the stabilizers. But instead of
machine screws through the outer surface,
1/4-20 nylon thumbscrews threaded through
the fuselage sides into each wing root,
keeping them tight against the framework.
Alignment between the wing and stabilizer
was accurate within 1/16 inch, which are
satisfactory tolerances.
The only glues needed to complete the
assembly were cyanoacrylate for the hinges
and RC/56 for the canopy. The only
deviation I made from the entire instruction
manual was to mount the prepainted canopy
with 4-40 nylon screws. Now I can touch up
the covering or add a pilot figure whenever
I’m ready.
The hardware package included with the
Showtime was exceptional. Weightwise, the
8-32 hardware was overkill, but it was a fair
trade when also included were slop-free ball
links and steel-bearing-supported clevises.
I never thought the term “spared no
expense” could be used when it came to
included ARF hardware, but I commend
Hangar 9 for this offering. From the carbonfiber
tail-wheel, to the socket-head screws,
to the rubber wheels and preassembled
seamless fuel tank, all of it was first-class.
I usually dread engine installation
because it’s a custom job that requires a
great deal of measuring, then measuring
again, with guessing mixed in, sprinkled
with patience and craftsmanship.
Mounting the engine in this model was a
breeze, owing to choosing one of the
recommended power options: the Saito
1.00. The predrilled firewall and detailed
instructions in the illustrated manual were
well ordered and helpful.Fitting the cowl was easy too because its
mounting holes were already drilled and
aligned with the 4-40 blind nuts in the
fuselage. As I pointed out, the manual was
well detailed and explained expert methods
for sizing and locating cutouts in the cowl to
accept the muffler, cylinder head, and
cooling exits.
To get the cowl to align perfectly with the
21/2-inch Tru-Turn spinner, I had only to
make the mounting holes slightly oblong on
the right side. That’s nothing a #4 washer
can’t hide.
Even though the best option is to spend
the extra money on the high-tech digital
servos, it doesn’t mean the pilot needs a
$1,000 transmitter to go along with it. The
JR 6102 radio is more than adequate to fly
the ShowTime with expert results.
To mix the dual elevator servos I used a
servo-reversing Y harness from
ElectroDynamics. This accessory was
especially handy because its heavy-duty
leads were just long enough to reach the tailmounted
servos.
I saved the rudder installation as the last
step after finding out how close the model
was to balancing around the recommended
CG. The flight pack and rudder servo were
my two ballast devices, and as it worked out
the battery found its home under the fuel
tank when the rudder servo was mounted
between the wings and connected with the
provided pull-pull cable system.
The ShowTime’s airframe was so
minimal that where to locate the power
switch was a tough choice. A miniswitch
would fit in the fuselage cutout provided, but
the heavy-duty JR switch wouldn’t. In
addition, I wanted the switch on the opposite
side from the exhaust.
I ended up making a cutout in the
fuselage against the aft edge of the former,
behind the fuel tank and hidden under the
wing LE.
The control-surface setup and radio
programming was a simple procedure. The
pushrods were provided at the correct length
and machined with right-hand threads on one
end and left-hand threads on the other.
The benefit of being able to fine-tune
these mechanical linkages is that the finished
pushrod assembly can be adjusted to a length
between half turns of the linkages. Extreme
control throws and large surfaces amplify the
slightest misalignments in the linkage
geometry. Experts in flying precision
aerobatics pay top dollar for accessories with
this feature.
Following the recommended mechanical
linkage setup in the book, full throw on the
channel’s travel volume control would
provide the recommended high rate
deflections. For my taste, 50%-75%
exponential was programmed into the high
rates.
To get the recommended low rates
required lowering the control-surface
deflections to 20%. Doing this diluted the
fidelity of the control-surface movement, but
the precision of the JR digital servos helps
make up for reduction in resolution. No
exponential was programmed into the low
rates.
The location of the Side Force Generators
(SFGs) did not affect the CG. Built up from
hard-balsa stock, they were rigid and easy to
install. Their purpose is to improve lateral
stability, knife-edge flight performance, and
rudder-input authority. They dramatically
change the looks of the model from the
profile view, but for the most part they don’t
affect recognition or orientation.
Flying: The ShowTime is as long as most
1/4-scale models I’ve owned, but it is
significantly easier to transport. By removing
the stabilizer halves and wing panels, the
long fuselage slides easily between the trunk
and fold-down seats of my Honda. It all bolts
back together with standard socket-head
bolts and thumb screws.
Because of the oversized tail wheel, the
ShowTime rests close to level on the ground.
As a result, the takeoff rotation is subtle. The
Saito 1.00 provides plenty of power for
liftoff at approximately the half-stick
position on the throttle. Climbout
performance is respectable, with only
roughly half throttle as well.
Overall, the ShowTime proved to be a
groovy airplane. Minor trim adjustments
were made to the controls; the model
basically flew right off the bench.
Level cruise can actually be performedquite slowly; only full power is needed to
drive the ShowTime upstairs. Climbout is
easy to resume from rolls and snaps on the
up-line. On the down-line, some elevator
down-trim is needed to hold the straight
line.
The recommended low rates felt
adequate for normal flying except in the
stall turns. The fix there for me was to
increase only the rudder low rate and add
approximately 30% exponential.
As a testimony to the accurate CG
placement, rolling maneuvers require almost
no rudder or elevator input to maintain
altitude and heading. (I’m sure the SFGs
help here too.) Inverted flight needs just a
breath of elevator to maintain level flight or
45° lines.
Knife-edge flight is easy with the
ShowTime. Experienced pilots will have to
“forget” about adding rudder while doing
point rolls. At slow speeds, increased rudder
input has only a minimal proverse roll
effect. Mixing can correct that or a pilot can
cross control the aileron input as needed.
Knife-edge loops? You got ’em! As big
or as small as you like.
High rate control with the heavy dose of
exponential is easy with which to get
comfortable. Almost the only warning I can
give you is to manage elevator input
carefully and watch for tip-stalling.
The ShowTime eventually reaches an
angle of attack and power setting where a
stall is unavoidable. The trick is to rescue
the model from the stall by adding power—
not more elevator. Mixing reflex into the
aileron controls will reduce tip-stalling.
Roughly 8° of input is all that is required to
keep the wings from “wagging” while flying
in a high-alpha condition.
I could do Waterfalls all day long with
the ShowTime. It tracks straight through the
maneuver, and almost no torque correction
is required during power application. It
didn’t take me long to bring the outside
Waterfall entry lower and lower to the
ground. I just knew that it would come
around, wings level and happy to do
another.
Okay, so the SFGs work great. Why
should they ever be removed, and how does
the ShowTime fly without them?
Almost the only time the SFGs were a
handicap was when flying in high winds—
particularly when they were cross. All that
extra side area worked like a sail on a
sailboat that doesn’t have a center board.
The model gets pushed, and to fly straight
requires a strong crab angle. The added drag
of the crab angle reduces the effective
power from the engine, which leads to poor
vertical performance.
When I flew without the SFGs,
penetration was improved in high winds.
The absence of the SFGs was noticeable
when it came to 3-D agility. It requires only
minutes to put them on or take them off,
which is a great option.
The ShowTime has a nice glide slope. Its
slippery lines improve the glide
performance, as does the light wing loadingFull-stall landings show no sign of tipstalling.
It’s easy to touch the tail wheel
before the main wheels. Don’t worry; the
carbon-fiber tail bracket can take it.
The ShowTime’s handling qualities are what
some would describe as “honest.” It goes
where you point it, with almost no adverse
reactions or coupling.
Mike McConville designed an excellent
model. The ability to perform a diverse list of
maneuvers excellently makes it a great
aerobatic model for any RC pilots who are
looking for an easy-to-assemble airplane that
will show them the ropes. MA
Michael Ramsey
Edition: Model Aviation - 2006/10
Page Numbers: 50,51,52,54,56
50 MODEL AVIATION
IF YOU’RE THROUGH throwing your
transmitter’s control sticks around
haphazardly and looking for an aircraft that
will help you hone your skills as a proficient
RC pilot (as apposed to mostly lucky),
you’re in the market for an RC Aerobatics
(Pattern) airplane. Because Pattern models
are designed to perform challenging
maneuvers gracefully, they have been
known to “make the pilot look good,” as it
has been put.
If there’s a “Pattern” pilot at you’re field,
perhaps you’ve taken the time to appreciate
that style of flying. The giant loops, slow
rolls that go from one end of the field to the
other, and snaps that start and finish crisply
from the same heading are beautiful, as they
should be; a proficient pilot
practices regularly.
If you enjoy how well these
people fly, be sure to let them know; they’ll
appreciate it. If you talk with these pilots for
a while, you might decide that flying
precision Aerobatics is your next step.
In any case, the Hangar 9 ShowTime 4D
from Horizon Hobby has all the goods of a
Pattern model, but it is also capable of being
a fantastic-tumbling 3-D aerobatics
performer. This model is appropriately sized
for those who don’t want to make the
obligation to plunge into a large 2-meterclass
Pattern aircraft but want the full flavor
of flying with grace and precision.
A number of the ShowTime’s key
Plane Talk: Hangar 9 ShowTime 4D 90 ARF
MICHAEL RAMSEY
Stabilizer halves are supported with an
anodized aluminum spar tube and located
with aluminum pins at the root. Elevator
linkage uses snap-on ball links.
Wing halves plug into the fuselage and are
drawn tight with 1/4-20 nylon thumbscrews.
All the parts are prealigned at the factory.
The recommended CG is spot-on for the author. Almost no down-stick pressure is
required to maintain an inverted cruise.
Even at half throttle
this model requires
little top rudder to
maintain a heading.
Almost no cross
control mixing is
needed.
An ARF sport model with the grace
of a Pattern airplane and the outof-
this-world performance of a
Freestyle model
10sig2.QXD 8/24/06 9:22 AM Page 50October 2006 51
The generous hatch size makes servicing
equipment easy. A six-cell, 1400 mAh
battery under the fuel tank brought the
CG to the exact location.
The Tru-Turn 21/2-inch spinner was finished with UltraCote Paint. There’s enough
propeller clearance to suit any choice of power plant.
The generous rudder needs a powerful servo such as the JR 8411SA for guidance. The
carbon-fiber tail wheel is a symbol of the high-quality hardware included.
Looking down the fuselage into the tail
reveals the molded sheeting in the bottom
corners. The reversing Y harness’s long
leads reached the elevator servos.
The Side Force Generators plug in and are
secured with a red (so you can find it in the
grass) thumbscrew. Knife-edge performance
is greatly enhanced with these installed.
The four-color UltraCote trim scheme offers a strong contrast between the model’s top
and bottom. The fuel tank comes plumbed and ready to install.
Photos by Mark Lanterman and the author
10sig2.QXD 8/24/06 9:25 AM Page 5152 MODEL AVIATION
• Brittle tail-wheel linkage springs
Pluses and Minuses
+
-
Test-Model Details
Engine used: Saito 1.00 four-stroke
Propeller: APC 14 x 8 (break-in), 15
x 4W (flying)
Fuel: 600cc (approximately 14
ounces) tank, Magnum #1
Radio system: JR 6102 transmitter,
JR 770S receiver, four JRPS9411
servos, one JRPS8411SA servo, one
JRPS537 servo, JR 1500 mAh 6.0-volt
battery, ElectroDynamics Pro Servo
Reverser Y, four 9-inch servo
extensions
Ready-to-fly weight: 8.69 pounds
Flight duration: Exceeds 10 minutes
Specifications
Type: RC sport aerobatic ARF
Pilot skill level: Advanced
Wingspan: 66 inches
Wing area: 900 square inches
Length: 68.3 inches
Weight: 8-9 pounds
Wing loading (average): 21.76
ounces per square foot
Engine: .61-1.00 (two-stroke) or .91-
1.10 (four-stroke) glow
Radio: Six channels (minimum), six
heavy-duty servos
Construction: All-wood airframe;
fiberglass wingtips, cowl, and wheel
pants; carbon-fiber landing gear; clear
smoked canopy
Covering/finish: Four-color genuine
UltraCote-film trim scheme, matching
fuelproof paint on landing gear,
cowling, canopy, wheel pants
Price: $199.99
• Fast assembly thanks to excellent
parts fit
• A+ hardware and accessory
package
• Flies like a dream
Saito FA-100 Engine
Four-stroke engines have been out long
enough that there’s nothing to be afraid
about when it comes to running and tuning
them. It’s true that a two-stroke engine has
fewer parts and is simpler to operate to
some extent, but the modern four-stroke is
a thing of beauty that produces gobs of
power.
The Saito FA-100 is worth seriously
considering if you have a 60-size model
that needs an engine. Compared with the
similarly displaced .91 Saito and same size
engines in competition, it will turn the
same 14 x 8 APC propeller 300-700 rpm
faster under the same conditions
(atmosphere, fuel, plug, etc.). Refinements
of the FA-100 even permitted the Saito
engineers to make it approximately 2
ounces lighter than most other .91 fourstrokes.
Don’t be afraid to mount the Saito
inverted. Forget the rumors you might have
heard about getting an engine to idle this
way. All it took with the ShowTime 4D
was low-speed needle tweaking and the
fuel metered perfectly for an all-day idle at
2,000 rpm (with no glow heat). Throttle
transition from these long idles is
immediate; slam the throttle stick to full
and the engine doesn’t cough, spit, or
stutter.
Nothing builds confidence in a new
airplane like the feeling you get when you
know the engine is reliable. The Saito FA-
100 required only a minimal run-in period
before it could be flown, and that was
done with the engine mounted in the
airplane just before the first flight.
Out of the box the engine showed no
bad habits. To get the idle right, the lowspeed
needle was leaned roughly 11/2 turns
from the flush factory setting. It’s not
unusual to excessively lean the low-end
adjustment, especially with an inverted
engine.
The ShowTime was first flown with an
APC 14 x 6 propeller with the Saito tuned
roughly 1/4 turn rich (this propeller is
smaller than recommended). The extra
fuel kept the engine cool even though it
was turning a high rpm (approximately
9,000).
For the next couple flights the engine
was leaned further but not peaked. After
the sixth flight the engine graduated to an
APC 14 x 8 propeller and was flown with
an optimal high-speed needle setting.
For fun-flying, a longer-diameter/
smaller-pitch propeller combination will
limit the top-end flight speed while
increasing the throttle response. For
hoverbatics, 3-D, and now 4-D flight,
you want as much thrust (air) rushing
over the control surfaces as possible to
improve their effectiveness. The next
step is to give the APC 15 x 4W
propeller a try. The engine “bump” starts
typically, and the starter is only needed
on the first flight of the day.
The Saito FA-100 is a clean-running
engine with a fuel system that is easy to set
up and tune. After roughly two hours of
flight time, the valves will be checked and
adjusted as needed. Tools and instructions
for this job are provided, making the short
maintenance task easy. MA
—Michael Ramsey
FA-100 Specifications
Type: Four-stroke
Displacement: 1.10 cu. in. (17.10 cc)
Bore: 1.14 inches (29.0 mm)
Stroke: 1.02 inches (26.0 mm)
Cylinder: Single—chrome plated (AAC)
Total weight: 20.9 ounces
Crankshaft threads: 8 x 1.25mm
Propeller range: 13 x 9-14 x 10
Rpm range: 2,000-11,000
Horsepower: 1.8
features illustrate its versatility. The fuselage
is stretched out long so the maneuvers it
draws through the air look smooth. The wing
and tail surfaces are fully symmetrical for
equal handling in upright and inverted
flying. The thicker tail surfaces also improve
their strength.
All movable control surfaces are
oversized, with hinge joints that are double
beveled to allow for an extreme rate of
control-surface deflection. For Pattern and
otherwise normal flying, only small amounts
of control throw are necessary. When a pilot
wants to fly in a more outrageous manner,
maximum control throw is available with
just the flick of a dual-rate switch, to help
with whatever stunts might be desired.
The ShowTime 4D is the best of both
worlds. It’s a Pattern model and a Freestyle
airplane, but the correct engine and radioaccessory
choices are essential to optimize
the performance potential.
Because of its lightweight airframe, this
model can be flown with a strong .61 twostroke
engine. However, it will do just that:
fly around, struggling with any maneuver
that requires climb performance. The .91-
1.10 class of two- and four-stroke glow
engines are excellent choices for the
ShowTime.
Although not recommended, the new
Saito 1.25 would make an excellent engine
The Saito FA-100 fit perfectly into the
included mounting beams attached to
the preinstalled blind nuts behind the
6mm firewall.
10sig2.QXD 8/24/06 9:26 AM Page 52choice for the Masters or FAI class
competitor who is looking for a smaller
practice model. The larger engine would
give the ShowTime an extra boost of power
for long vertical lines containing snap and
rolling maneuvers along the way.
However, power management would be
essential to flying this model in an
overpowered condition. Large control
surfaces and high-speed flight take their toll
on an airframe, especially when flutter is
induced. Unless you’re willing to take the
risk, stick with the recommended engine
recommendations. Regardless, good throttle
management is a sensible practice.
The servos recommended by the
manufacturer are the best available on the
market. To fully experience the ShowTime’s
capabilities, I don’t recommend deviating
from the servo-output requirements.
With any RC model, how good the
servos are will determine how well the
model can be controlled. That point is more
evident in the ShowTime because of the
oversized control surfaces and high rate of
deflection.
Although it’s basically a .60-size
model—where 50 inch-ounce power servos
might typically work fine—the ShowTime is
special. Powerful and silky-smooth-moving
servos will make a distinct difference in how
this model flies.
I used the recommended digital servos
and experienced excellent results. If I werebudget-conscious, one option might be to
choose similar-power-output servos that
weren’t digital but at least had a coreless
motor drive.
The ShowTime is an excellent candidate
for electric-power conversion. The weight
distribution and servo-location options
make this model an ideal choice.
The large cockpit hatch makes servicing
convenient, so getting a power pack in and
out of the model would be a nonissue.
You’d want at least a 900- to 1,500-watt
power system. The stock carbon-fiber
landing gear is long enough to support up to
an 18-inch propeller, so either a direct drive
or gearbox system could be operated.
ShowTime on the Bench: Assembling this
model was the most fun I’ve had putting an
ARF together in sometime. Quality
construction and engineering had a lot to do
with that.
I liked that critical areas of alignment
were already prepared at the factory. The
vertical fin was built into the fuselage, so it
arrived as straight as it was ever going to be.
The stabilizer and elevators were provided
as mirror assemblies that plugged into the
tail section using aluminum tube spars and
alignment pins through fiberglass sockets
built into the fuselage. Everything was
aligned, so I just bolted it on.
The wings attached in roughly the same
way as the stabilizers. But instead of
machine screws through the outer surface,
1/4-20 nylon thumbscrews threaded through
the fuselage sides into each wing root,
keeping them tight against the framework.
Alignment between the wing and stabilizer
was accurate within 1/16 inch, which are
satisfactory tolerances.
The only glues needed to complete the
assembly were cyanoacrylate for the hinges
and RC/56 for the canopy. The only
deviation I made from the entire instruction
manual was to mount the prepainted canopy
with 4-40 nylon screws. Now I can touch up
the covering or add a pilot figure whenever
I’m ready.
The hardware package included with the
Showtime was exceptional. Weightwise, the
8-32 hardware was overkill, but it was a fair
trade when also included were slop-free ball
links and steel-bearing-supported clevises.
I never thought the term “spared no
expense” could be used when it came to
included ARF hardware, but I commend
Hangar 9 for this offering. From the carbonfiber
tail-wheel, to the socket-head screws,
to the rubber wheels and preassembled
seamless fuel tank, all of it was first-class.
I usually dread engine installation
because it’s a custom job that requires a
great deal of measuring, then measuring
again, with guessing mixed in, sprinkled
with patience and craftsmanship.
Mounting the engine in this model was a
breeze, owing to choosing one of the
recommended power options: the Saito
1.00. The predrilled firewall and detailed
instructions in the illustrated manual were
well ordered and helpful.Fitting the cowl was easy too because its
mounting holes were already drilled and
aligned with the 4-40 blind nuts in the
fuselage. As I pointed out, the manual was
well detailed and explained expert methods
for sizing and locating cutouts in the cowl to
accept the muffler, cylinder head, and
cooling exits.
To get the cowl to align perfectly with the
21/2-inch Tru-Turn spinner, I had only to
make the mounting holes slightly oblong on
the right side. That’s nothing a #4 washer
can’t hide.
Even though the best option is to spend
the extra money on the high-tech digital
servos, it doesn’t mean the pilot needs a
$1,000 transmitter to go along with it. The
JR 6102 radio is more than adequate to fly
the ShowTime with expert results.
To mix the dual elevator servos I used a
servo-reversing Y harness from
ElectroDynamics. This accessory was
especially handy because its heavy-duty
leads were just long enough to reach the tailmounted
servos.
I saved the rudder installation as the last
step after finding out how close the model
was to balancing around the recommended
CG. The flight pack and rudder servo were
my two ballast devices, and as it worked out
the battery found its home under the fuel
tank when the rudder servo was mounted
between the wings and connected with the
provided pull-pull cable system.
The ShowTime’s airframe was so
minimal that where to locate the power
switch was a tough choice. A miniswitch
would fit in the fuselage cutout provided, but
the heavy-duty JR switch wouldn’t. In
addition, I wanted the switch on the opposite
side from the exhaust.
I ended up making a cutout in the
fuselage against the aft edge of the former,
behind the fuel tank and hidden under the
wing LE.
The control-surface setup and radio
programming was a simple procedure. The
pushrods were provided at the correct length
and machined with right-hand threads on one
end and left-hand threads on the other.
The benefit of being able to fine-tune
these mechanical linkages is that the finished
pushrod assembly can be adjusted to a length
between half turns of the linkages. Extreme
control throws and large surfaces amplify the
slightest misalignments in the linkage
geometry. Experts in flying precision
aerobatics pay top dollar for accessories with
this feature.
Following the recommended mechanical
linkage setup in the book, full throw on the
channel’s travel volume control would
provide the recommended high rate
deflections. For my taste, 50%-75%
exponential was programmed into the high
rates.
To get the recommended low rates
required lowering the control-surface
deflections to 20%. Doing this diluted the
fidelity of the control-surface movement, but
the precision of the JR digital servos helps
make up for reduction in resolution. No
exponential was programmed into the low
rates.
The location of the Side Force Generators
(SFGs) did not affect the CG. Built up from
hard-balsa stock, they were rigid and easy to
install. Their purpose is to improve lateral
stability, knife-edge flight performance, and
rudder-input authority. They dramatically
change the looks of the model from the
profile view, but for the most part they don’t
affect recognition or orientation.
Flying: The ShowTime is as long as most
1/4-scale models I’ve owned, but it is
significantly easier to transport. By removing
the stabilizer halves and wing panels, the
long fuselage slides easily between the trunk
and fold-down seats of my Honda. It all bolts
back together with standard socket-head
bolts and thumb screws.
Because of the oversized tail wheel, the
ShowTime rests close to level on the ground.
As a result, the takeoff rotation is subtle. The
Saito 1.00 provides plenty of power for
liftoff at approximately the half-stick
position on the throttle. Climbout
performance is respectable, with only
roughly half throttle as well.
Overall, the ShowTime proved to be a
groovy airplane. Minor trim adjustments
were made to the controls; the model
basically flew right off the bench.
Level cruise can actually be performedquite slowly; only full power is needed to
drive the ShowTime upstairs. Climbout is
easy to resume from rolls and snaps on the
up-line. On the down-line, some elevator
down-trim is needed to hold the straight
line.
The recommended low rates felt
adequate for normal flying except in the
stall turns. The fix there for me was to
increase only the rudder low rate and add
approximately 30% exponential.
As a testimony to the accurate CG
placement, rolling maneuvers require almost
no rudder or elevator input to maintain
altitude and heading. (I’m sure the SFGs
help here too.) Inverted flight needs just a
breath of elevator to maintain level flight or
45° lines.
Knife-edge flight is easy with the
ShowTime. Experienced pilots will have to
“forget” about adding rudder while doing
point rolls. At slow speeds, increased rudder
input has only a minimal proverse roll
effect. Mixing can correct that or a pilot can
cross control the aileron input as needed.
Knife-edge loops? You got ’em! As big
or as small as you like.
High rate control with the heavy dose of
exponential is easy with which to get
comfortable. Almost the only warning I can
give you is to manage elevator input
carefully and watch for tip-stalling.
The ShowTime eventually reaches an
angle of attack and power setting where a
stall is unavoidable. The trick is to rescue
the model from the stall by adding power—
not more elevator. Mixing reflex into the
aileron controls will reduce tip-stalling.
Roughly 8° of input is all that is required to
keep the wings from “wagging” while flying
in a high-alpha condition.
I could do Waterfalls all day long with
the ShowTime. It tracks straight through the
maneuver, and almost no torque correction
is required during power application. It
didn’t take me long to bring the outside
Waterfall entry lower and lower to the
ground. I just knew that it would come
around, wings level and happy to do
another.
Okay, so the SFGs work great. Why
should they ever be removed, and how does
the ShowTime fly without them?
Almost the only time the SFGs were a
handicap was when flying in high winds—
particularly when they were cross. All that
extra side area worked like a sail on a
sailboat that doesn’t have a center board.
The model gets pushed, and to fly straight
requires a strong crab angle. The added drag
of the crab angle reduces the effective
power from the engine, which leads to poor
vertical performance.
When I flew without the SFGs,
penetration was improved in high winds.
The absence of the SFGs was noticeable
when it came to 3-D agility. It requires only
minutes to put them on or take them off,
which is a great option.
The ShowTime has a nice glide slope. Its
slippery lines improve the glide
performance, as does the light wing loadingFull-stall landings show no sign of tipstalling.
It’s easy to touch the tail wheel
before the main wheels. Don’t worry; the
carbon-fiber tail bracket can take it.
The ShowTime’s handling qualities are what
some would describe as “honest.” It goes
where you point it, with almost no adverse
reactions or coupling.
Mike McConville designed an excellent
model. The ability to perform a diverse list of
maneuvers excellently makes it a great
aerobatic model for any RC pilots who are
looking for an easy-to-assemble airplane that
will show them the ropes. MA
Michael Ramsey
Edition: Model Aviation - 2006/10
Page Numbers: 50,51,52,54,56
50 MODEL AVIATION
IF YOU’RE THROUGH throwing your
transmitter’s control sticks around
haphazardly and looking for an aircraft that
will help you hone your skills as a proficient
RC pilot (as apposed to mostly lucky),
you’re in the market for an RC Aerobatics
(Pattern) airplane. Because Pattern models
are designed to perform challenging
maneuvers gracefully, they have been
known to “make the pilot look good,” as it
has been put.
If there’s a “Pattern” pilot at you’re field,
perhaps you’ve taken the time to appreciate
that style of flying. The giant loops, slow
rolls that go from one end of the field to the
other, and snaps that start and finish crisply
from the same heading are beautiful, as they
should be; a proficient pilot
practices regularly.
If you enjoy how well these
people fly, be sure to let them know; they’ll
appreciate it. If you talk with these pilots for
a while, you might decide that flying
precision Aerobatics is your next step.
In any case, the Hangar 9 ShowTime 4D
from Horizon Hobby has all the goods of a
Pattern model, but it is also capable of being
a fantastic-tumbling 3-D aerobatics
performer. This model is appropriately sized
for those who don’t want to make the
obligation to plunge into a large 2-meterclass
Pattern aircraft but want the full flavor
of flying with grace and precision.
A number of the ShowTime’s key
Plane Talk: Hangar 9 ShowTime 4D 90 ARF
MICHAEL RAMSEY
Stabilizer halves are supported with an
anodized aluminum spar tube and located
with aluminum pins at the root. Elevator
linkage uses snap-on ball links.
Wing halves plug into the fuselage and are
drawn tight with 1/4-20 nylon thumbscrews.
All the parts are prealigned at the factory.
The recommended CG is spot-on for the author. Almost no down-stick pressure is
required to maintain an inverted cruise.
Even at half throttle
this model requires
little top rudder to
maintain a heading.
Almost no cross
control mixing is
needed.
An ARF sport model with the grace
of a Pattern airplane and the outof-
this-world performance of a
Freestyle model
10sig2.QXD 8/24/06 9:22 AM Page 50October 2006 51
The generous hatch size makes servicing
equipment easy. A six-cell, 1400 mAh
battery under the fuel tank brought the
CG to the exact location.
The Tru-Turn 21/2-inch spinner was finished with UltraCote Paint. There’s enough
propeller clearance to suit any choice of power plant.
The generous rudder needs a powerful servo such as the JR 8411SA for guidance. The
carbon-fiber tail wheel is a symbol of the high-quality hardware included.
Looking down the fuselage into the tail
reveals the molded sheeting in the bottom
corners. The reversing Y harness’s long
leads reached the elevator servos.
The Side Force Generators plug in and are
secured with a red (so you can find it in the
grass) thumbscrew. Knife-edge performance
is greatly enhanced with these installed.
The four-color UltraCote trim scheme offers a strong contrast between the model’s top
and bottom. The fuel tank comes plumbed and ready to install.
Photos by Mark Lanterman and the author
10sig2.QXD 8/24/06 9:25 AM Page 5152 MODEL AVIATION
• Brittle tail-wheel linkage springs
Pluses and Minuses
+
-
Test-Model Details
Engine used: Saito 1.00 four-stroke
Propeller: APC 14 x 8 (break-in), 15
x 4W (flying)
Fuel: 600cc (approximately 14
ounces) tank, Magnum #1
Radio system: JR 6102 transmitter,
JR 770S receiver, four JRPS9411
servos, one JRPS8411SA servo, one
JRPS537 servo, JR 1500 mAh 6.0-volt
battery, ElectroDynamics Pro Servo
Reverser Y, four 9-inch servo
extensions
Ready-to-fly weight: 8.69 pounds
Flight duration: Exceeds 10 minutes
Specifications
Type: RC sport aerobatic ARF
Pilot skill level: Advanced
Wingspan: 66 inches
Wing area: 900 square inches
Length: 68.3 inches
Weight: 8-9 pounds
Wing loading (average): 21.76
ounces per square foot
Engine: .61-1.00 (two-stroke) or .91-
1.10 (four-stroke) glow
Radio: Six channels (minimum), six
heavy-duty servos
Construction: All-wood airframe;
fiberglass wingtips, cowl, and wheel
pants; carbon-fiber landing gear; clear
smoked canopy
Covering/finish: Four-color genuine
UltraCote-film trim scheme, matching
fuelproof paint on landing gear,
cowling, canopy, wheel pants
Price: $199.99
• Fast assembly thanks to excellent
parts fit
• A+ hardware and accessory
package
• Flies like a dream
Saito FA-100 Engine
Four-stroke engines have been out long
enough that there’s nothing to be afraid
about when it comes to running and tuning
them. It’s true that a two-stroke engine has
fewer parts and is simpler to operate to
some extent, but the modern four-stroke is
a thing of beauty that produces gobs of
power.
The Saito FA-100 is worth seriously
considering if you have a 60-size model
that needs an engine. Compared with the
similarly displaced .91 Saito and same size
engines in competition, it will turn the
same 14 x 8 APC propeller 300-700 rpm
faster under the same conditions
(atmosphere, fuel, plug, etc.). Refinements
of the FA-100 even permitted the Saito
engineers to make it approximately 2
ounces lighter than most other .91 fourstrokes.
Don’t be afraid to mount the Saito
inverted. Forget the rumors you might have
heard about getting an engine to idle this
way. All it took with the ShowTime 4D
was low-speed needle tweaking and the
fuel metered perfectly for an all-day idle at
2,000 rpm (with no glow heat). Throttle
transition from these long idles is
immediate; slam the throttle stick to full
and the engine doesn’t cough, spit, or
stutter.
Nothing builds confidence in a new
airplane like the feeling you get when you
know the engine is reliable. The Saito FA-
100 required only a minimal run-in period
before it could be flown, and that was
done with the engine mounted in the
airplane just before the first flight.
Out of the box the engine showed no
bad habits. To get the idle right, the lowspeed
needle was leaned roughly 11/2 turns
from the flush factory setting. It’s not
unusual to excessively lean the low-end
adjustment, especially with an inverted
engine.
The ShowTime was first flown with an
APC 14 x 6 propeller with the Saito tuned
roughly 1/4 turn rich (this propeller is
smaller than recommended). The extra
fuel kept the engine cool even though it
was turning a high rpm (approximately
9,000).
For the next couple flights the engine
was leaned further but not peaked. After
the sixth flight the engine graduated to an
APC 14 x 8 propeller and was flown with
an optimal high-speed needle setting.
For fun-flying, a longer-diameter/
smaller-pitch propeller combination will
limit the top-end flight speed while
increasing the throttle response. For
hoverbatics, 3-D, and now 4-D flight,
you want as much thrust (air) rushing
over the control surfaces as possible to
improve their effectiveness. The next
step is to give the APC 15 x 4W
propeller a try. The engine “bump” starts
typically, and the starter is only needed
on the first flight of the day.
The Saito FA-100 is a clean-running
engine with a fuel system that is easy to set
up and tune. After roughly two hours of
flight time, the valves will be checked and
adjusted as needed. Tools and instructions
for this job are provided, making the short
maintenance task easy. MA
—Michael Ramsey
FA-100 Specifications
Type: Four-stroke
Displacement: 1.10 cu. in. (17.10 cc)
Bore: 1.14 inches (29.0 mm)
Stroke: 1.02 inches (26.0 mm)
Cylinder: Single—chrome plated (AAC)
Total weight: 20.9 ounces
Crankshaft threads: 8 x 1.25mm
Propeller range: 13 x 9-14 x 10
Rpm range: 2,000-11,000
Horsepower: 1.8
features illustrate its versatility. The fuselage
is stretched out long so the maneuvers it
draws through the air look smooth. The wing
and tail surfaces are fully symmetrical for
equal handling in upright and inverted
flying. The thicker tail surfaces also improve
their strength.
All movable control surfaces are
oversized, with hinge joints that are double
beveled to allow for an extreme rate of
control-surface deflection. For Pattern and
otherwise normal flying, only small amounts
of control throw are necessary. When a pilot
wants to fly in a more outrageous manner,
maximum control throw is available with
just the flick of a dual-rate switch, to help
with whatever stunts might be desired.
The ShowTime 4D is the best of both
worlds. It’s a Pattern model and a Freestyle
airplane, but the correct engine and radioaccessory
choices are essential to optimize
the performance potential.
Because of its lightweight airframe, this
model can be flown with a strong .61 twostroke
engine. However, it will do just that:
fly around, struggling with any maneuver
that requires climb performance. The .91-
1.10 class of two- and four-stroke glow
engines are excellent choices for the
ShowTime.
Although not recommended, the new
Saito 1.25 would make an excellent engine
The Saito FA-100 fit perfectly into the
included mounting beams attached to
the preinstalled blind nuts behind the
6mm firewall.
10sig2.QXD 8/24/06 9:26 AM Page 52choice for the Masters or FAI class
competitor who is looking for a smaller
practice model. The larger engine would
give the ShowTime an extra boost of power
for long vertical lines containing snap and
rolling maneuvers along the way.
However, power management would be
essential to flying this model in an
overpowered condition. Large control
surfaces and high-speed flight take their toll
on an airframe, especially when flutter is
induced. Unless you’re willing to take the
risk, stick with the recommended engine
recommendations. Regardless, good throttle
management is a sensible practice.
The servos recommended by the
manufacturer are the best available on the
market. To fully experience the ShowTime’s
capabilities, I don’t recommend deviating
from the servo-output requirements.
With any RC model, how good the
servos are will determine how well the
model can be controlled. That point is more
evident in the ShowTime because of the
oversized control surfaces and high rate of
deflection.
Although it’s basically a .60-size
model—where 50 inch-ounce power servos
might typically work fine—the ShowTime is
special. Powerful and silky-smooth-moving
servos will make a distinct difference in how
this model flies.
I used the recommended digital servos
and experienced excellent results. If I werebudget-conscious, one option might be to
choose similar-power-output servos that
weren’t digital but at least had a coreless
motor drive.
The ShowTime is an excellent candidate
for electric-power conversion. The weight
distribution and servo-location options
make this model an ideal choice.
The large cockpit hatch makes servicing
convenient, so getting a power pack in and
out of the model would be a nonissue.
You’d want at least a 900- to 1,500-watt
power system. The stock carbon-fiber
landing gear is long enough to support up to
an 18-inch propeller, so either a direct drive
or gearbox system could be operated.
ShowTime on the Bench: Assembling this
model was the most fun I’ve had putting an
ARF together in sometime. Quality
construction and engineering had a lot to do
with that.
I liked that critical areas of alignment
were already prepared at the factory. The
vertical fin was built into the fuselage, so it
arrived as straight as it was ever going to be.
The stabilizer and elevators were provided
as mirror assemblies that plugged into the
tail section using aluminum tube spars and
alignment pins through fiberglass sockets
built into the fuselage. Everything was
aligned, so I just bolted it on.
The wings attached in roughly the same
way as the stabilizers. But instead of
machine screws through the outer surface,
1/4-20 nylon thumbscrews threaded through
the fuselage sides into each wing root,
keeping them tight against the framework.
Alignment between the wing and stabilizer
was accurate within 1/16 inch, which are
satisfactory tolerances.
The only glues needed to complete the
assembly were cyanoacrylate for the hinges
and RC/56 for the canopy. The only
deviation I made from the entire instruction
manual was to mount the prepainted canopy
with 4-40 nylon screws. Now I can touch up
the covering or add a pilot figure whenever
I’m ready.
The hardware package included with the
Showtime was exceptional. Weightwise, the
8-32 hardware was overkill, but it was a fair
trade when also included were slop-free ball
links and steel-bearing-supported clevises.
I never thought the term “spared no
expense” could be used when it came to
included ARF hardware, but I commend
Hangar 9 for this offering. From the carbonfiber
tail-wheel, to the socket-head screws,
to the rubber wheels and preassembled
seamless fuel tank, all of it was first-class.
I usually dread engine installation
because it’s a custom job that requires a
great deal of measuring, then measuring
again, with guessing mixed in, sprinkled
with patience and craftsmanship.
Mounting the engine in this model was a
breeze, owing to choosing one of the
recommended power options: the Saito
1.00. The predrilled firewall and detailed
instructions in the illustrated manual were
well ordered and helpful.Fitting the cowl was easy too because its
mounting holes were already drilled and
aligned with the 4-40 blind nuts in the
fuselage. As I pointed out, the manual was
well detailed and explained expert methods
for sizing and locating cutouts in the cowl to
accept the muffler, cylinder head, and
cooling exits.
To get the cowl to align perfectly with the
21/2-inch Tru-Turn spinner, I had only to
make the mounting holes slightly oblong on
the right side. That’s nothing a #4 washer
can’t hide.
Even though the best option is to spend
the extra money on the high-tech digital
servos, it doesn’t mean the pilot needs a
$1,000 transmitter to go along with it. The
JR 6102 radio is more than adequate to fly
the ShowTime with expert results.
To mix the dual elevator servos I used a
servo-reversing Y harness from
ElectroDynamics. This accessory was
especially handy because its heavy-duty
leads were just long enough to reach the tailmounted
servos.
I saved the rudder installation as the last
step after finding out how close the model
was to balancing around the recommended
CG. The flight pack and rudder servo were
my two ballast devices, and as it worked out
the battery found its home under the fuel
tank when the rudder servo was mounted
between the wings and connected with the
provided pull-pull cable system.
The ShowTime’s airframe was so
minimal that where to locate the power
switch was a tough choice. A miniswitch
would fit in the fuselage cutout provided, but
the heavy-duty JR switch wouldn’t. In
addition, I wanted the switch on the opposite
side from the exhaust.
I ended up making a cutout in the
fuselage against the aft edge of the former,
behind the fuel tank and hidden under the
wing LE.
The control-surface setup and radio
programming was a simple procedure. The
pushrods were provided at the correct length
and machined with right-hand threads on one
end and left-hand threads on the other.
The benefit of being able to fine-tune
these mechanical linkages is that the finished
pushrod assembly can be adjusted to a length
between half turns of the linkages. Extreme
control throws and large surfaces amplify the
slightest misalignments in the linkage
geometry. Experts in flying precision
aerobatics pay top dollar for accessories with
this feature.
Following the recommended mechanical
linkage setup in the book, full throw on the
channel’s travel volume control would
provide the recommended high rate
deflections. For my taste, 50%-75%
exponential was programmed into the high
rates.
To get the recommended low rates
required lowering the control-surface
deflections to 20%. Doing this diluted the
fidelity of the control-surface movement, but
the precision of the JR digital servos helps
make up for reduction in resolution. No
exponential was programmed into the low
rates.
The location of the Side Force Generators
(SFGs) did not affect the CG. Built up from
hard-balsa stock, they were rigid and easy to
install. Their purpose is to improve lateral
stability, knife-edge flight performance, and
rudder-input authority. They dramatically
change the looks of the model from the
profile view, but for the most part they don’t
affect recognition or orientation.
Flying: The ShowTime is as long as most
1/4-scale models I’ve owned, but it is
significantly easier to transport. By removing
the stabilizer halves and wing panels, the
long fuselage slides easily between the trunk
and fold-down seats of my Honda. It all bolts
back together with standard socket-head
bolts and thumb screws.
Because of the oversized tail wheel, the
ShowTime rests close to level on the ground.
As a result, the takeoff rotation is subtle. The
Saito 1.00 provides plenty of power for
liftoff at approximately the half-stick
position on the throttle. Climbout
performance is respectable, with only
roughly half throttle as well.
Overall, the ShowTime proved to be a
groovy airplane. Minor trim adjustments
were made to the controls; the model
basically flew right off the bench.
Level cruise can actually be performedquite slowly; only full power is needed to
drive the ShowTime upstairs. Climbout is
easy to resume from rolls and snaps on the
up-line. On the down-line, some elevator
down-trim is needed to hold the straight
line.
The recommended low rates felt
adequate for normal flying except in the
stall turns. The fix there for me was to
increase only the rudder low rate and add
approximately 30% exponential.
As a testimony to the accurate CG
placement, rolling maneuvers require almost
no rudder or elevator input to maintain
altitude and heading. (I’m sure the SFGs
help here too.) Inverted flight needs just a
breath of elevator to maintain level flight or
45° lines.
Knife-edge flight is easy with the
ShowTime. Experienced pilots will have to
“forget” about adding rudder while doing
point rolls. At slow speeds, increased rudder
input has only a minimal proverse roll
effect. Mixing can correct that or a pilot can
cross control the aileron input as needed.
Knife-edge loops? You got ’em! As big
or as small as you like.
High rate control with the heavy dose of
exponential is easy with which to get
comfortable. Almost the only warning I can
give you is to manage elevator input
carefully and watch for tip-stalling.
The ShowTime eventually reaches an
angle of attack and power setting where a
stall is unavoidable. The trick is to rescue
the model from the stall by adding power—
not more elevator. Mixing reflex into the
aileron controls will reduce tip-stalling.
Roughly 8° of input is all that is required to
keep the wings from “wagging” while flying
in a high-alpha condition.
I could do Waterfalls all day long with
the ShowTime. It tracks straight through the
maneuver, and almost no torque correction
is required during power application. It
didn’t take me long to bring the outside
Waterfall entry lower and lower to the
ground. I just knew that it would come
around, wings level and happy to do
another.
Okay, so the SFGs work great. Why
should they ever be removed, and how does
the ShowTime fly without them?
Almost the only time the SFGs were a
handicap was when flying in high winds—
particularly when they were cross. All that
extra side area worked like a sail on a
sailboat that doesn’t have a center board.
The model gets pushed, and to fly straight
requires a strong crab angle. The added drag
of the crab angle reduces the effective
power from the engine, which leads to poor
vertical performance.
When I flew without the SFGs,
penetration was improved in high winds.
The absence of the SFGs was noticeable
when it came to 3-D agility. It requires only
minutes to put them on or take them off,
which is a great option.
The ShowTime has a nice glide slope. Its
slippery lines improve the glide
performance, as does the light wing loadingFull-stall landings show no sign of tipstalling.
It’s easy to touch the tail wheel
before the main wheels. Don’t worry; the
carbon-fiber tail bracket can take it.
The ShowTime’s handling qualities are what
some would describe as “honest.” It goes
where you point it, with almost no adverse
reactions or coupling.
Mike McConville designed an excellent
model. The ability to perform a diverse list of
maneuvers excellently makes it a great
aerobatic model for any RC pilots who are
looking for an easy-to-assemble airplane that
will show them the ropes. MA
Michael Ramsey
Edition: Model Aviation - 2006/10
Page Numbers: 50,51,52,54,56
50 MODEL AVIATION
IF YOU’RE THROUGH throwing your
transmitter’s control sticks around
haphazardly and looking for an aircraft that
will help you hone your skills as a proficient
RC pilot (as apposed to mostly lucky),
you’re in the market for an RC Aerobatics
(Pattern) airplane. Because Pattern models
are designed to perform challenging
maneuvers gracefully, they have been
known to “make the pilot look good,” as it
has been put.
If there’s a “Pattern” pilot at you’re field,
perhaps you’ve taken the time to appreciate
that style of flying. The giant loops, slow
rolls that go from one end of the field to the
other, and snaps that start and finish crisply
from the same heading are beautiful, as they
should be; a proficient pilot
practices regularly.
If you enjoy how well these
people fly, be sure to let them know; they’ll
appreciate it. If you talk with these pilots for
a while, you might decide that flying
precision Aerobatics is your next step.
In any case, the Hangar 9 ShowTime 4D
from Horizon Hobby has all the goods of a
Pattern model, but it is also capable of being
a fantastic-tumbling 3-D aerobatics
performer. This model is appropriately sized
for those who don’t want to make the
obligation to plunge into a large 2-meterclass
Pattern aircraft but want the full flavor
of flying with grace and precision.
A number of the ShowTime’s key
Plane Talk: Hangar 9 ShowTime 4D 90 ARF
MICHAEL RAMSEY
Stabilizer halves are supported with an
anodized aluminum spar tube and located
with aluminum pins at the root. Elevator
linkage uses snap-on ball links.
Wing halves plug into the fuselage and are
drawn tight with 1/4-20 nylon thumbscrews.
All the parts are prealigned at the factory.
The recommended CG is spot-on for the author. Almost no down-stick pressure is
required to maintain an inverted cruise.
Even at half throttle
this model requires
little top rudder to
maintain a heading.
Almost no cross
control mixing is
needed.
An ARF sport model with the grace
of a Pattern airplane and the outof-
this-world performance of a
Freestyle model
10sig2.QXD 8/24/06 9:22 AM Page 50October 2006 51
The generous hatch size makes servicing
equipment easy. A six-cell, 1400 mAh
battery under the fuel tank brought the
CG to the exact location.
The Tru-Turn 21/2-inch spinner was finished with UltraCote Paint. There’s enough
propeller clearance to suit any choice of power plant.
The generous rudder needs a powerful servo such as the JR 8411SA for guidance. The
carbon-fiber tail wheel is a symbol of the high-quality hardware included.
Looking down the fuselage into the tail
reveals the molded sheeting in the bottom
corners. The reversing Y harness’s long
leads reached the elevator servos.
The Side Force Generators plug in and are
secured with a red (so you can find it in the
grass) thumbscrew. Knife-edge performance
is greatly enhanced with these installed.
The four-color UltraCote trim scheme offers a strong contrast between the model’s top
and bottom. The fuel tank comes plumbed and ready to install.
Photos by Mark Lanterman and the author
10sig2.QXD 8/24/06 9:25 AM Page 5152 MODEL AVIATION
• Brittle tail-wheel linkage springs
Pluses and Minuses
+
-
Test-Model Details
Engine used: Saito 1.00 four-stroke
Propeller: APC 14 x 8 (break-in), 15
x 4W (flying)
Fuel: 600cc (approximately 14
ounces) tank, Magnum #1
Radio system: JR 6102 transmitter,
JR 770S receiver, four JRPS9411
servos, one JRPS8411SA servo, one
JRPS537 servo, JR 1500 mAh 6.0-volt
battery, ElectroDynamics Pro Servo
Reverser Y, four 9-inch servo
extensions
Ready-to-fly weight: 8.69 pounds
Flight duration: Exceeds 10 minutes
Specifications
Type: RC sport aerobatic ARF
Pilot skill level: Advanced
Wingspan: 66 inches
Wing area: 900 square inches
Length: 68.3 inches
Weight: 8-9 pounds
Wing loading (average): 21.76
ounces per square foot
Engine: .61-1.00 (two-stroke) or .91-
1.10 (four-stroke) glow
Radio: Six channels (minimum), six
heavy-duty servos
Construction: All-wood airframe;
fiberglass wingtips, cowl, and wheel
pants; carbon-fiber landing gear; clear
smoked canopy
Covering/finish: Four-color genuine
UltraCote-film trim scheme, matching
fuelproof paint on landing gear,
cowling, canopy, wheel pants
Price: $199.99
• Fast assembly thanks to excellent
parts fit
• A+ hardware and accessory
package
• Flies like a dream
Saito FA-100 Engine
Four-stroke engines have been out long
enough that there’s nothing to be afraid
about when it comes to running and tuning
them. It’s true that a two-stroke engine has
fewer parts and is simpler to operate to
some extent, but the modern four-stroke is
a thing of beauty that produces gobs of
power.
The Saito FA-100 is worth seriously
considering if you have a 60-size model
that needs an engine. Compared with the
similarly displaced .91 Saito and same size
engines in competition, it will turn the
same 14 x 8 APC propeller 300-700 rpm
faster under the same conditions
(atmosphere, fuel, plug, etc.). Refinements
of the FA-100 even permitted the Saito
engineers to make it approximately 2
ounces lighter than most other .91 fourstrokes.
Don’t be afraid to mount the Saito
inverted. Forget the rumors you might have
heard about getting an engine to idle this
way. All it took with the ShowTime 4D
was low-speed needle tweaking and the
fuel metered perfectly for an all-day idle at
2,000 rpm (with no glow heat). Throttle
transition from these long idles is
immediate; slam the throttle stick to full
and the engine doesn’t cough, spit, or
stutter.
Nothing builds confidence in a new
airplane like the feeling you get when you
know the engine is reliable. The Saito FA-
100 required only a minimal run-in period
before it could be flown, and that was
done with the engine mounted in the
airplane just before the first flight.
Out of the box the engine showed no
bad habits. To get the idle right, the lowspeed
needle was leaned roughly 11/2 turns
from the flush factory setting. It’s not
unusual to excessively lean the low-end
adjustment, especially with an inverted
engine.
The ShowTime was first flown with an
APC 14 x 6 propeller with the Saito tuned
roughly 1/4 turn rich (this propeller is
smaller than recommended). The extra
fuel kept the engine cool even though it
was turning a high rpm (approximately
9,000).
For the next couple flights the engine
was leaned further but not peaked. After
the sixth flight the engine graduated to an
APC 14 x 8 propeller and was flown with
an optimal high-speed needle setting.
For fun-flying, a longer-diameter/
smaller-pitch propeller combination will
limit the top-end flight speed while
increasing the throttle response. For
hoverbatics, 3-D, and now 4-D flight,
you want as much thrust (air) rushing
over the control surfaces as possible to
improve their effectiveness. The next
step is to give the APC 15 x 4W
propeller a try. The engine “bump” starts
typically, and the starter is only needed
on the first flight of the day.
The Saito FA-100 is a clean-running
engine with a fuel system that is easy to set
up and tune. After roughly two hours of
flight time, the valves will be checked and
adjusted as needed. Tools and instructions
for this job are provided, making the short
maintenance task easy. MA
—Michael Ramsey
FA-100 Specifications
Type: Four-stroke
Displacement: 1.10 cu. in. (17.10 cc)
Bore: 1.14 inches (29.0 mm)
Stroke: 1.02 inches (26.0 mm)
Cylinder: Single—chrome plated (AAC)
Total weight: 20.9 ounces
Crankshaft threads: 8 x 1.25mm
Propeller range: 13 x 9-14 x 10
Rpm range: 2,000-11,000
Horsepower: 1.8
features illustrate its versatility. The fuselage
is stretched out long so the maneuvers it
draws through the air look smooth. The wing
and tail surfaces are fully symmetrical for
equal handling in upright and inverted
flying. The thicker tail surfaces also improve
their strength.
All movable control surfaces are
oversized, with hinge joints that are double
beveled to allow for an extreme rate of
control-surface deflection. For Pattern and
otherwise normal flying, only small amounts
of control throw are necessary. When a pilot
wants to fly in a more outrageous manner,
maximum control throw is available with
just the flick of a dual-rate switch, to help
with whatever stunts might be desired.
The ShowTime 4D is the best of both
worlds. It’s a Pattern model and a Freestyle
airplane, but the correct engine and radioaccessory
choices are essential to optimize
the performance potential.
Because of its lightweight airframe, this
model can be flown with a strong .61 twostroke
engine. However, it will do just that:
fly around, struggling with any maneuver
that requires climb performance. The .91-
1.10 class of two- and four-stroke glow
engines are excellent choices for the
ShowTime.
Although not recommended, the new
Saito 1.25 would make an excellent engine
The Saito FA-100 fit perfectly into the
included mounting beams attached to
the preinstalled blind nuts behind the
6mm firewall.
10sig2.QXD 8/24/06 9:26 AM Page 52choice for the Masters or FAI class
competitor who is looking for a smaller
practice model. The larger engine would
give the ShowTime an extra boost of power
for long vertical lines containing snap and
rolling maneuvers along the way.
However, power management would be
essential to flying this model in an
overpowered condition. Large control
surfaces and high-speed flight take their toll
on an airframe, especially when flutter is
induced. Unless you’re willing to take the
risk, stick with the recommended engine
recommendations. Regardless, good throttle
management is a sensible practice.
The servos recommended by the
manufacturer are the best available on the
market. To fully experience the ShowTime’s
capabilities, I don’t recommend deviating
from the servo-output requirements.
With any RC model, how good the
servos are will determine how well the
model can be controlled. That point is more
evident in the ShowTime because of the
oversized control surfaces and high rate of
deflection.
Although it’s basically a .60-size
model—where 50 inch-ounce power servos
might typically work fine—the ShowTime is
special. Powerful and silky-smooth-moving
servos will make a distinct difference in how
this model flies.
I used the recommended digital servos
and experienced excellent results. If I werebudget-conscious, one option might be to
choose similar-power-output servos that
weren’t digital but at least had a coreless
motor drive.
The ShowTime is an excellent candidate
for electric-power conversion. The weight
distribution and servo-location options
make this model an ideal choice.
The large cockpit hatch makes servicing
convenient, so getting a power pack in and
out of the model would be a nonissue.
You’d want at least a 900- to 1,500-watt
power system. The stock carbon-fiber
landing gear is long enough to support up to
an 18-inch propeller, so either a direct drive
or gearbox system could be operated.
ShowTime on the Bench: Assembling this
model was the most fun I’ve had putting an
ARF together in sometime. Quality
construction and engineering had a lot to do
with that.
I liked that critical areas of alignment
were already prepared at the factory. The
vertical fin was built into the fuselage, so it
arrived as straight as it was ever going to be.
The stabilizer and elevators were provided
as mirror assemblies that plugged into the
tail section using aluminum tube spars and
alignment pins through fiberglass sockets
built into the fuselage. Everything was
aligned, so I just bolted it on.
The wings attached in roughly the same
way as the stabilizers. But instead of
machine screws through the outer surface,
1/4-20 nylon thumbscrews threaded through
the fuselage sides into each wing root,
keeping them tight against the framework.
Alignment between the wing and stabilizer
was accurate within 1/16 inch, which are
satisfactory tolerances.
The only glues needed to complete the
assembly were cyanoacrylate for the hinges
and RC/56 for the canopy. The only
deviation I made from the entire instruction
manual was to mount the prepainted canopy
with 4-40 nylon screws. Now I can touch up
the covering or add a pilot figure whenever
I’m ready.
The hardware package included with the
Showtime was exceptional. Weightwise, the
8-32 hardware was overkill, but it was a fair
trade when also included were slop-free ball
links and steel-bearing-supported clevises.
I never thought the term “spared no
expense” could be used when it came to
included ARF hardware, but I commend
Hangar 9 for this offering. From the carbonfiber
tail-wheel, to the socket-head screws,
to the rubber wheels and preassembled
seamless fuel tank, all of it was first-class.
I usually dread engine installation
because it’s a custom job that requires a
great deal of measuring, then measuring
again, with guessing mixed in, sprinkled
with patience and craftsmanship.
Mounting the engine in this model was a
breeze, owing to choosing one of the
recommended power options: the Saito
1.00. The predrilled firewall and detailed
instructions in the illustrated manual were
well ordered and helpful.Fitting the cowl was easy too because its
mounting holes were already drilled and
aligned with the 4-40 blind nuts in the
fuselage. As I pointed out, the manual was
well detailed and explained expert methods
for sizing and locating cutouts in the cowl to
accept the muffler, cylinder head, and
cooling exits.
To get the cowl to align perfectly with the
21/2-inch Tru-Turn spinner, I had only to
make the mounting holes slightly oblong on
the right side. That’s nothing a #4 washer
can’t hide.
Even though the best option is to spend
the extra money on the high-tech digital
servos, it doesn’t mean the pilot needs a
$1,000 transmitter to go along with it. The
JR 6102 radio is more than adequate to fly
the ShowTime with expert results.
To mix the dual elevator servos I used a
servo-reversing Y harness from
ElectroDynamics. This accessory was
especially handy because its heavy-duty
leads were just long enough to reach the tailmounted
servos.
I saved the rudder installation as the last
step after finding out how close the model
was to balancing around the recommended
CG. The flight pack and rudder servo were
my two ballast devices, and as it worked out
the battery found its home under the fuel
tank when the rudder servo was mounted
between the wings and connected with the
provided pull-pull cable system.
The ShowTime’s airframe was so
minimal that where to locate the power
switch was a tough choice. A miniswitch
would fit in the fuselage cutout provided, but
the heavy-duty JR switch wouldn’t. In
addition, I wanted the switch on the opposite
side from the exhaust.
I ended up making a cutout in the
fuselage against the aft edge of the former,
behind the fuel tank and hidden under the
wing LE.
The control-surface setup and radio
programming was a simple procedure. The
pushrods were provided at the correct length
and machined with right-hand threads on one
end and left-hand threads on the other.
The benefit of being able to fine-tune
these mechanical linkages is that the finished
pushrod assembly can be adjusted to a length
between half turns of the linkages. Extreme
control throws and large surfaces amplify the
slightest misalignments in the linkage
geometry. Experts in flying precision
aerobatics pay top dollar for accessories with
this feature.
Following the recommended mechanical
linkage setup in the book, full throw on the
channel’s travel volume control would
provide the recommended high rate
deflections. For my taste, 50%-75%
exponential was programmed into the high
rates.
To get the recommended low rates
required lowering the control-surface
deflections to 20%. Doing this diluted the
fidelity of the control-surface movement, but
the precision of the JR digital servos helps
make up for reduction in resolution. No
exponential was programmed into the low
rates.
The location of the Side Force Generators
(SFGs) did not affect the CG. Built up from
hard-balsa stock, they were rigid and easy to
install. Their purpose is to improve lateral
stability, knife-edge flight performance, and
rudder-input authority. They dramatically
change the looks of the model from the
profile view, but for the most part they don’t
affect recognition or orientation.
Flying: The ShowTime is as long as most
1/4-scale models I’ve owned, but it is
significantly easier to transport. By removing
the stabilizer halves and wing panels, the
long fuselage slides easily between the trunk
and fold-down seats of my Honda. It all bolts
back together with standard socket-head
bolts and thumb screws.
Because of the oversized tail wheel, the
ShowTime rests close to level on the ground.
As a result, the takeoff rotation is subtle. The
Saito 1.00 provides plenty of power for
liftoff at approximately the half-stick
position on the throttle. Climbout
performance is respectable, with only
roughly half throttle as well.
Overall, the ShowTime proved to be a
groovy airplane. Minor trim adjustments
were made to the controls; the model
basically flew right off the bench.
Level cruise can actually be performedquite slowly; only full power is needed to
drive the ShowTime upstairs. Climbout is
easy to resume from rolls and snaps on the
up-line. On the down-line, some elevator
down-trim is needed to hold the straight
line.
The recommended low rates felt
adequate for normal flying except in the
stall turns. The fix there for me was to
increase only the rudder low rate and add
approximately 30% exponential.
As a testimony to the accurate CG
placement, rolling maneuvers require almost
no rudder or elevator input to maintain
altitude and heading. (I’m sure the SFGs
help here too.) Inverted flight needs just a
breath of elevator to maintain level flight or
45° lines.
Knife-edge flight is easy with the
ShowTime. Experienced pilots will have to
“forget” about adding rudder while doing
point rolls. At slow speeds, increased rudder
input has only a minimal proverse roll
effect. Mixing can correct that or a pilot can
cross control the aileron input as needed.
Knife-edge loops? You got ’em! As big
or as small as you like.
High rate control with the heavy dose of
exponential is easy with which to get
comfortable. Almost the only warning I can
give you is to manage elevator input
carefully and watch for tip-stalling.
The ShowTime eventually reaches an
angle of attack and power setting where a
stall is unavoidable. The trick is to rescue
the model from the stall by adding power—
not more elevator. Mixing reflex into the
aileron controls will reduce tip-stalling.
Roughly 8° of input is all that is required to
keep the wings from “wagging” while flying
in a high-alpha condition.
I could do Waterfalls all day long with
the ShowTime. It tracks straight through the
maneuver, and almost no torque correction
is required during power application. It
didn’t take me long to bring the outside
Waterfall entry lower and lower to the
ground. I just knew that it would come
around, wings level and happy to do
another.
Okay, so the SFGs work great. Why
should they ever be removed, and how does
the ShowTime fly without them?
Almost the only time the SFGs were a
handicap was when flying in high winds—
particularly when they were cross. All that
extra side area worked like a sail on a
sailboat that doesn’t have a center board.
The model gets pushed, and to fly straight
requires a strong crab angle. The added drag
of the crab angle reduces the effective
power from the engine, which leads to poor
vertical performance.
When I flew without the SFGs,
penetration was improved in high winds.
The absence of the SFGs was noticeable
when it came to 3-D agility. It requires only
minutes to put them on or take them off,
which is a great option.
The ShowTime has a nice glide slope. Its
slippery lines improve the glide
performance, as does the light wing loadingFull-stall landings show no sign of tipstalling.
It’s easy to touch the tail wheel
before the main wheels. Don’t worry; the
carbon-fiber tail bracket can take it.
The ShowTime’s handling qualities are what
some would describe as “honest.” It goes
where you point it, with almost no adverse
reactions or coupling.
Mike McConville designed an excellent
model. The ability to perform a diverse list of
maneuvers excellently makes it a great
aerobatic model for any RC pilots who are
looking for an easy-to-assemble airplane that
will show them the ropes. MA
Michael Ramsey