78 MODEL AVIATION
BY ROTH HEYES
A semiscale, IMAA-legal
model of the classic homebuilt racer
All the builder needs to supply to
complete the scale look of this
model is a pilot bust.
The Minnow is a fast mover
with electric or glow power.
Plane Talk: Great Planes Cosmic Wind Minnow ARF
Little rudder input is needed to hold the Minnow in knife-edge
flight at three-quarters throttle.
Cooling holes in the right cowl cheek are finished at the factory.
Notice the two-color painted landing gear.
THE MINNOW IS Great Planes’ newest addition to its Cosmic
Wind racer line. This excellent sport model has a scale twist that
makes it eligible to fly at IMAA (International Miniature Aircraft
Association) events, and it is easy to land.
The box in which the model arrived was appealing. It showed
great pictures of the completed model so you could see exactly what
you would have sitting on your shop table in just a few days. After
examining the pictures I couldn’t wait to open the box and get a
firsthand look at what was inside.
The prepainted fiberglass fuselage was beautiful, and it was
obvious that not much work was going to be needed to get it ready to
10sig3.QXD 8/23/07 2:38 PM Page 78
October 2007 79
The fiberglass parts are finished with two-part polyurethane paint.
The wood parts are finished with MonoKote.
Underneath the builder-supplied battery tray are the receiver and
radio battery. Heavy-duty servos are recommended.
Photos by Michael Ramsey
A homemade jumper arms the power
system. The rubber band makes the plug
easy to find.
The 8 x 32 threaded rods allow the motor
to be easily adjusted for position and
thrust angle.
The female plug of a Deans connector is
spliced between the positive leads of the
battery.
The wing assembly is secured with two 1/4-
20 nylon screws, which makes battery
access quick.
The 1/8 light-plywood tray fits in a tongue at the firewall and is held down with Velcro
straps in the back. The 10S Li-Poly battery system is extremely efficient.
fly. All the formers were preinstalled, including the fuel-tank mount. I
removed that since I chose to convert this model to electric power.
The servo trays and pushrod guides were also installed. The
pushrod exits were faired into the fuselage on the tail section. I thought
this was a nice touch.
The next parts of the model I checked out were the wing halves. I
was pleased to see the nice covering job and the precut hatch covers.
There was a piece of string inside the wing halves to assist in threading
the servo leads through the wing.
The painted fiberglass cowl and wheel pants were impressive. The
latter had antirotation screw holes predrilled and blind nuts already
installed.
I was extremely pleased with all the Minnow’s parts, but I was
particularly happy with the landing gear. Its construction was sturdy,
which was great, but it was also painted.
The top of the gear was red to match the top of the airplane and the
bottom of the gear was white to match the bottom of the airplane. This
extra attention to the paint scheme completed the overall appeal when
the Minnow was complete.
As I mentioned, I converted this model to electric power. Since so
10sig3.QXD 8/23/07 2:08 PM Page 79
80 MODEL AVIATION
Pluses and Minuses
Type: Semiscale ARF
Pilot skill level: Intermediate to expert
Wingspan: 63 inches
Wing area: 775 square inches
Length: 56.5 inches
Weight: 7.25-8.25 pounds
Wing loading: 22-25 ounces/square foot
Engine: .61 two-stroke or .91 four-stroke
Radio: Four channels, five servos
Construction: Balsa, light plywood,
molded fiberglass fuselage
Covering/finish: Polyurethane paint,
MonoKote covering
Price: $219.99
Specifications
The painted fuselage matched
extraordinarily well with the trim lines of
the fiberglass cowling.
Trim the self-adhesive decals as tight as
possible for that professional appearance.
The thin airfoil offers little drag. Landing approaches are long, but the Minnow is stable
enough for a full-stall touchdown. The scale spinner is a nice touch.
Room in the stabilizer saddle is left for
shimming the horizontal stabilizer to align
with the wing.
Left: Carbon-fiber pushrods from Central
Hobbies were substituted for the aileron
linkages.
Below: The included metal pushrods offer
a solid link from the tail surfaces to the
servos under the wing.
Motor used: aero-naut actro 40-4
Propeller: APC 14 x 10-15 x 11
Radio system: Futaba 14MZ transmitter,
Futaba R319 receiver, Futaba digital
servos, 7.4-volt Li-Poly receiver battery,
6.0-volt regulator
Power system: Castle Creations
Phoenix-110HV ESC, two Tanic 5S3P
5400 mAh Li-Poly battery packs
connected in series
Output: 1,200-1,400 watts at 54-59
amps, 7,500-8,100 rpm
Ready-to-fly weight: 8 pounds
Flight duration: 10 minutes
Test-Model Details
+
• Accurate scale outline
• Beautiful fiberglass work and
painted parts
• Can easily be converted to electric
power for sport or performance
power
-• None noted
10sig3.QXD 8/23/07 2:18 PM Page 80
much work was already completed on it, it
was the perfect choice because build time was
really not increased.
I needed to determine which motor, speed
controller, and batteries would be required.
After placing a quick phone call to Hobby
Lobby I decided to use the actro 40-4 motor
(now distributed by Dymond Modelsport
Ltd.). I picked the Castle Creations Phoenix-
110HV speed controller because of the high
voltage capabilities and ease of use and setup.
The Minnow was designed to be a racer,
so I wanted the extra voltage from the 10S
pack to go to good use. A large-diameter
propeller with a deep pitch would get me the
performance that is characteristic of the
prototype.
I chose the Tanic Li-Poly batteries because
of their high C rating. Brian Nakonechny at
Tanic told me he could build two 5S3P 5400
mAh packs with the cells arranged sideways,
permitting the 20C discharge-rate packs to fit
completely in the nose. That would leave the
CG unaffected.
Once all the electric-conversion parts
arrived, it was time to decide how to mount
the motor on the firewall. I encountered my
first conversion challenge at this point. I could
not mount the short actro motor directly on
the firewall because it would not reach the
front of the cowl.
I drew on my motor-mounting experience
and decided I would need a few additional
82 MODEL AVIATION
parts: four 12-inch lengths of 8/32 threaded
rod, 12 sets of 8/32 nuts and washers, and a
solid plate of 3mm carbon fiber.
All those items were easy to get at The
Home Depot except for the carbon-fiber plate.
I ordered it online from Mach V Motorsports,
which is an automotive shop that uses carbon
fiber to make dashboards, hoods, etc.
It is important to take appropriate
precautions when working with carbon fiber.
Wear a respirator to keep the dust from
getting into your lungs and make sure to
cover your skin to minimize irritation.
I covered the carbon-fiber plate with
masking tape so I could mark the areas that
needed to be cut and drilled. I used a compass
to draw a perfect 3-inch circle on the masking
tape.
I drilled the necessary holes to mount the
motor to the plate and then drilled the holes
that were required to attach the plate to the
firewall. Once that was finished I removed the
tape and attached the plate to the motor.
I screwed the threaded rods in place and
marked the points on the firewall where the
new holes were going to have to be drilled.
Once the holes were made I attached the
motor and carbon-fiber plate to the firewall
using the 8/32 rods. I placed the cowl on the
airplane and made fine adjustments to the
threaded rods to make the spinner backplate
line up with the cowl.
With the motor installation complete, it
was time to decide where the speed controller
should go. The cowl came with holes on the
lower right cheek to allow for cooling the
head on a glow engine, so I decided to use
those to help keep the controller cool.
I drilled four holes in the nose section
(engine box) for two zip ties that would be
used to hold the controller in place. (The cowl
covered these holes, so they are invisible.)
The next step required some thought
before jumping in. The batteries had to be
installed in the Minnow’s nose because of
where the servo tray was located. To
accomplish this I had to cut out the fuel-tank
mount and install a keeper block of wood in
the nose. This would allow for a plate, with
the batteries attached, to slide under it to keep
it from moving during flight.
I made the battery plate from 3/16 birch
plywood for its strength and stiffness. I
designed the tray to go from the Minnow’s
nose back to the servo tray and to be held in
place with hook-and-loop fastener. I built
another accessory mounting plate under the
battery tray to accommodate the receiver, the
6-volt regulator, and the flight-pack battery.
I mentioned that I had the battery packs
specially built to help keep the CG in check.
This design was phenomenal. The packs were
built so one side had more cells than the other,
and this worked great by having the heavier
side to the back of the airplane and as far back
as possible on the plate. With the packs
located there, the balance was exactly where
the instruction book called for it to be.
With the airplane balanced, it was time to
set up the radio. I did this just as the
directions called for on the high and low
rates.
However, I added a twist to the setup; I
made a third high rate for the ailerons. With
all the travels and dual rates set, the last step
was to put in 30% exponential to slightly
soften everything to my liking.
With the model’s mechanical steps
complete, there were just a few finishing
touches left. This ARF came with decals.
When applied they looked great and
enhanced the Minnow’s look. Applying all
the letters was time-consuming but not too
difficult, and the outcome was well worth it.
Once all the letters were applied, I put on the
spinner and took some pictures.
At this point the Minnow was ready to test
run, and I had to make sure the amp draw was
acceptable. I turned on the transmitter
followed by the receiver in the airplane, but
even with the switch turned on the motor was
not live since the onboard safety still needed
to be plugged in.
The onboard safety consisted of a simple
jumper on the outside of the fuselage. The
model was not armed until it was plugged in.
Once the airplane was armed, it was time
to check the amps. The actro was pulling 58
amps on an APC 15 x 8E propeller. It felt like
it was going to have tons of power.
Flying: With these final tests completed, I
packed up the Minnow and headed to the
field. When I pulled into the parking area the
members started migrating to my truck to see
what new and interesting aircraft I had.
Everyone was impressed with this Great
Planes release. Many commented on the
fiberglass fuselage’s nice construction and
how well the paint and MonoKote matched. I
spent some time answering questions and
explaining how I converted the Minnow to
electric power, and then it was time to fly.
I performed a quick range and control test,
and then I released the Minnow to taxi down
the runway. At the end of the runway I
completed one last control check and then
slowly added power.
The Minnow lifted off at half power and
took to the sky. Immediately after takeoff I
could tell that it was going to fly well. After a
few clicks of up-elevator trim and one click of
right aileron trim, the model was flying level
and with hands off.
After a few passes to check the trim it was
time to play around to see what the Minnow
could do. I started with some loops and rolls
and found it to be precise. It carved through
the air extremely well—almost like an
Aerobatics airplane.
I tried some more difficult maneuvers:
Four Point Rolls, Eight Point Rolls, some
Slow Rolls. Wow! This airplane flew like it
was on rails!
I set up for landing with a nice, long
approach to allow the Minnow enough room
to slow to touchdown speed. As it rolled out
on final on a nice speed, just a hint of upelevator
was needed to raise the nose to the
proper touchdown angle.
After landing and taxiing back, I took out
the batteries to see how they were doing. I
was delighted to see the cell temperatures at
only 110°. That was great; it meant everything
was working correctly and nothing was
overheating or having to work too hard.
After determining that all the equipment
was performing perfectly, I decided to make
another flight to test the Minnow’s
performance while increasing its speed. The
second flight proved to be as exciting as the
first.
I applied half power for the takeoff, and
the model held a nice climbout angle. It did a
Split S from the climbout and headed back
down the runway, and I increased the throttle
to wide open. The model kept accelerating
down the runway. I banked it to the left like a
pylon turn, leveled it out, banked it to the left
again, and took it back to level.
The Minnow looked great and performed
extremely well at high speeds. It was graceful
and carved its way around the track.
After landing, people at the field told me
how impressed they were with the airplane. It
was quiet yet fast, a cinch to fly, and fully
aerobatic. This is a terrific model! MA
Roth Heyes
[email protected]
Manufacturer/Distributor:
Great Planes Hobby Distributors
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com
Items Used in Review:
Futaba radio equipment
www.futaba-rc.com
Castle Creations ESC
www.castlecreations.com
Tanic Li-Poly batteries
www.tanicpacks.com
Carbon-fiber plate
www.machv.com
Aero-naut actro motor
www.rc-dymond.com
Accessories
www.hobby-lobby.com
Other Review Sources:
Model Airplane News: February 2006
RCMF: February 2005 and June 2006
RC Report: December 2005
Fly RC: October 2006
Edition: Model Aviation - 2007/10
Page Numbers: 78,79,80,82,84
Edition: Model Aviation - 2007/10
Page Numbers: 78,79,80,82,84
78 MODEL AVIATION
BY ROTH HEYES
A semiscale, IMAA-legal
model of the classic homebuilt racer
All the builder needs to supply to
complete the scale look of this
model is a pilot bust.
The Minnow is a fast mover
with electric or glow power.
Plane Talk: Great Planes Cosmic Wind Minnow ARF
Little rudder input is needed to hold the Minnow in knife-edge
flight at three-quarters throttle.
Cooling holes in the right cowl cheek are finished at the factory.
Notice the two-color painted landing gear.
THE MINNOW IS Great Planes’ newest addition to its Cosmic
Wind racer line. This excellent sport model has a scale twist that
makes it eligible to fly at IMAA (International Miniature Aircraft
Association) events, and it is easy to land.
The box in which the model arrived was appealing. It showed
great pictures of the completed model so you could see exactly what
you would have sitting on your shop table in just a few days. After
examining the pictures I couldn’t wait to open the box and get a
firsthand look at what was inside.
The prepainted fiberglass fuselage was beautiful, and it was
obvious that not much work was going to be needed to get it ready to
10sig3.QXD 8/23/07 2:38 PM Page 78
October 2007 79
The fiberglass parts are finished with two-part polyurethane paint.
The wood parts are finished with MonoKote.
Underneath the builder-supplied battery tray are the receiver and
radio battery. Heavy-duty servos are recommended.
Photos by Michael Ramsey
A homemade jumper arms the power
system. The rubber band makes the plug
easy to find.
The 8 x 32 threaded rods allow the motor
to be easily adjusted for position and
thrust angle.
The female plug of a Deans connector is
spliced between the positive leads of the
battery.
The wing assembly is secured with two 1/4-
20 nylon screws, which makes battery
access quick.
The 1/8 light-plywood tray fits in a tongue at the firewall and is held down with Velcro
straps in the back. The 10S Li-Poly battery system is extremely efficient.
fly. All the formers were preinstalled, including the fuel-tank mount. I
removed that since I chose to convert this model to electric power.
The servo trays and pushrod guides were also installed. The
pushrod exits were faired into the fuselage on the tail section. I thought
this was a nice touch.
The next parts of the model I checked out were the wing halves. I
was pleased to see the nice covering job and the precut hatch covers.
There was a piece of string inside the wing halves to assist in threading
the servo leads through the wing.
The painted fiberglass cowl and wheel pants were impressive. The
latter had antirotation screw holes predrilled and blind nuts already
installed.
I was extremely pleased with all the Minnow’s parts, but I was
particularly happy with the landing gear. Its construction was sturdy,
which was great, but it was also painted.
The top of the gear was red to match the top of the airplane and the
bottom of the gear was white to match the bottom of the airplane. This
extra attention to the paint scheme completed the overall appeal when
the Minnow was complete.
As I mentioned, I converted this model to electric power. Since so
10sig3.QXD 8/23/07 2:08 PM Page 79
80 MODEL AVIATION
Pluses and Minuses
Type: Semiscale ARF
Pilot skill level: Intermediate to expert
Wingspan: 63 inches
Wing area: 775 square inches
Length: 56.5 inches
Weight: 7.25-8.25 pounds
Wing loading: 22-25 ounces/square foot
Engine: .61 two-stroke or .91 four-stroke
Radio: Four channels, five servos
Construction: Balsa, light plywood,
molded fiberglass fuselage
Covering/finish: Polyurethane paint,
MonoKote covering
Price: $219.99
Specifications
The painted fuselage matched
extraordinarily well with the trim lines of
the fiberglass cowling.
Trim the self-adhesive decals as tight as
possible for that professional appearance.
The thin airfoil offers little drag. Landing approaches are long, but the Minnow is stable
enough for a full-stall touchdown. The scale spinner is a nice touch.
Room in the stabilizer saddle is left for
shimming the horizontal stabilizer to align
with the wing.
Left: Carbon-fiber pushrods from Central
Hobbies were substituted for the aileron
linkages.
Below: The included metal pushrods offer
a solid link from the tail surfaces to the
servos under the wing.
Motor used: aero-naut actro 40-4
Propeller: APC 14 x 10-15 x 11
Radio system: Futaba 14MZ transmitter,
Futaba R319 receiver, Futaba digital
servos, 7.4-volt Li-Poly receiver battery,
6.0-volt regulator
Power system: Castle Creations
Phoenix-110HV ESC, two Tanic 5S3P
5400 mAh Li-Poly battery packs
connected in series
Output: 1,200-1,400 watts at 54-59
amps, 7,500-8,100 rpm
Ready-to-fly weight: 8 pounds
Flight duration: 10 minutes
Test-Model Details
+
• Accurate scale outline
• Beautiful fiberglass work and
painted parts
• Can easily be converted to electric
power for sport or performance
power
-• None noted
10sig3.QXD 8/23/07 2:18 PM Page 80
much work was already completed on it, it
was the perfect choice because build time was
really not increased.
I needed to determine which motor, speed
controller, and batteries would be required.
After placing a quick phone call to Hobby
Lobby I decided to use the actro 40-4 motor
(now distributed by Dymond Modelsport
Ltd.). I picked the Castle Creations Phoenix-
110HV speed controller because of the high
voltage capabilities and ease of use and setup.
The Minnow was designed to be a racer,
so I wanted the extra voltage from the 10S
pack to go to good use. A large-diameter
propeller with a deep pitch would get me the
performance that is characteristic of the
prototype.
I chose the Tanic Li-Poly batteries because
of their high C rating. Brian Nakonechny at
Tanic told me he could build two 5S3P 5400
mAh packs with the cells arranged sideways,
permitting the 20C discharge-rate packs to fit
completely in the nose. That would leave the
CG unaffected.
Once all the electric-conversion parts
arrived, it was time to decide how to mount
the motor on the firewall. I encountered my
first conversion challenge at this point. I could
not mount the short actro motor directly on
the firewall because it would not reach the
front of the cowl.
I drew on my motor-mounting experience
and decided I would need a few additional
82 MODEL AVIATION
parts: four 12-inch lengths of 8/32 threaded
rod, 12 sets of 8/32 nuts and washers, and a
solid plate of 3mm carbon fiber.
All those items were easy to get at The
Home Depot except for the carbon-fiber plate.
I ordered it online from Mach V Motorsports,
which is an automotive shop that uses carbon
fiber to make dashboards, hoods, etc.
It is important to take appropriate
precautions when working with carbon fiber.
Wear a respirator to keep the dust from
getting into your lungs and make sure to
cover your skin to minimize irritation.
I covered the carbon-fiber plate with
masking tape so I could mark the areas that
needed to be cut and drilled. I used a compass
to draw a perfect 3-inch circle on the masking
tape.
I drilled the necessary holes to mount the
motor to the plate and then drilled the holes
that were required to attach the plate to the
firewall. Once that was finished I removed the
tape and attached the plate to the motor.
I screwed the threaded rods in place and
marked the points on the firewall where the
new holes were going to have to be drilled.
Once the holes were made I attached the
motor and carbon-fiber plate to the firewall
using the 8/32 rods. I placed the cowl on the
airplane and made fine adjustments to the
threaded rods to make the spinner backplate
line up with the cowl.
With the motor installation complete, it
was time to decide where the speed controller
should go. The cowl came with holes on the
lower right cheek to allow for cooling the
head on a glow engine, so I decided to use
those to help keep the controller cool.
I drilled four holes in the nose section
(engine box) for two zip ties that would be
used to hold the controller in place. (The cowl
covered these holes, so they are invisible.)
The next step required some thought
before jumping in. The batteries had to be
installed in the Minnow’s nose because of
where the servo tray was located. To
accomplish this I had to cut out the fuel-tank
mount and install a keeper block of wood in
the nose. This would allow for a plate, with
the batteries attached, to slide under it to keep
it from moving during flight.
I made the battery plate from 3/16 birch
plywood for its strength and stiffness. I
designed the tray to go from the Minnow’s
nose back to the servo tray and to be held in
place with hook-and-loop fastener. I built
another accessory mounting plate under the
battery tray to accommodate the receiver, the
6-volt regulator, and the flight-pack battery.
I mentioned that I had the battery packs
specially built to help keep the CG in check.
This design was phenomenal. The packs were
built so one side had more cells than the other,
and this worked great by having the heavier
side to the back of the airplane and as far back
as possible on the plate. With the packs
located there, the balance was exactly where
the instruction book called for it to be.
With the airplane balanced, it was time to
set up the radio. I did this just as the
directions called for on the high and low
rates.
However, I added a twist to the setup; I
made a third high rate for the ailerons. With
all the travels and dual rates set, the last step
was to put in 30% exponential to slightly
soften everything to my liking.
With the model’s mechanical steps
complete, there were just a few finishing
touches left. This ARF came with decals.
When applied they looked great and
enhanced the Minnow’s look. Applying all
the letters was time-consuming but not too
difficult, and the outcome was well worth it.
Once all the letters were applied, I put on the
spinner and took some pictures.
At this point the Minnow was ready to test
run, and I had to make sure the amp draw was
acceptable. I turned on the transmitter
followed by the receiver in the airplane, but
even with the switch turned on the motor was
not live since the onboard safety still needed
to be plugged in.
The onboard safety consisted of a simple
jumper on the outside of the fuselage. The
model was not armed until it was plugged in.
Once the airplane was armed, it was time
to check the amps. The actro was pulling 58
amps on an APC 15 x 8E propeller. It felt like
it was going to have tons of power.
Flying: With these final tests completed, I
packed up the Minnow and headed to the
field. When I pulled into the parking area the
members started migrating to my truck to see
what new and interesting aircraft I had.
Everyone was impressed with this Great
Planes release. Many commented on the
fiberglass fuselage’s nice construction and
how well the paint and MonoKote matched. I
spent some time answering questions and
explaining how I converted the Minnow to
electric power, and then it was time to fly.
I performed a quick range and control test,
and then I released the Minnow to taxi down
the runway. At the end of the runway I
completed one last control check and then
slowly added power.
The Minnow lifted off at half power and
took to the sky. Immediately after takeoff I
could tell that it was going to fly well. After a
few clicks of up-elevator trim and one click of
right aileron trim, the model was flying level
and with hands off.
After a few passes to check the trim it was
time to play around to see what the Minnow
could do. I started with some loops and rolls
and found it to be precise. It carved through
the air extremely well—almost like an
Aerobatics airplane.
I tried some more difficult maneuvers:
Four Point Rolls, Eight Point Rolls, some
Slow Rolls. Wow! This airplane flew like it
was on rails!
I set up for landing with a nice, long
approach to allow the Minnow enough room
to slow to touchdown speed. As it rolled out
on final on a nice speed, just a hint of upelevator
was needed to raise the nose to the
proper touchdown angle.
After landing and taxiing back, I took out
the batteries to see how they were doing. I
was delighted to see the cell temperatures at
only 110°. That was great; it meant everything
was working correctly and nothing was
overheating or having to work too hard.
After determining that all the equipment
was performing perfectly, I decided to make
another flight to test the Minnow’s
performance while increasing its speed. The
second flight proved to be as exciting as the
first.
I applied half power for the takeoff, and
the model held a nice climbout angle. It did a
Split S from the climbout and headed back
down the runway, and I increased the throttle
to wide open. The model kept accelerating
down the runway. I banked it to the left like a
pylon turn, leveled it out, banked it to the left
again, and took it back to level.
The Minnow looked great and performed
extremely well at high speeds. It was graceful
and carved its way around the track.
After landing, people at the field told me
how impressed they were with the airplane. It
was quiet yet fast, a cinch to fly, and fully
aerobatic. This is a terrific model! MA
Roth Heyes
[email protected]
Manufacturer/Distributor:
Great Planes Hobby Distributors
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com
Items Used in Review:
Futaba radio equipment
www.futaba-rc.com
Castle Creations ESC
www.castlecreations.com
Tanic Li-Poly batteries
www.tanicpacks.com
Carbon-fiber plate
www.machv.com
Aero-naut actro motor
www.rc-dymond.com
Accessories
www.hobby-lobby.com
Other Review Sources:
Model Airplane News: February 2006
RCMF: February 2005 and June 2006
RC Report: December 2005
Fly RC: October 2006
Edition: Model Aviation - 2007/10
Page Numbers: 78,79,80,82,84
78 MODEL AVIATION
BY ROTH HEYES
A semiscale, IMAA-legal
model of the classic homebuilt racer
All the builder needs to supply to
complete the scale look of this
model is a pilot bust.
The Minnow is a fast mover
with electric or glow power.
Plane Talk: Great Planes Cosmic Wind Minnow ARF
Little rudder input is needed to hold the Minnow in knife-edge
flight at three-quarters throttle.
Cooling holes in the right cowl cheek are finished at the factory.
Notice the two-color painted landing gear.
THE MINNOW IS Great Planes’ newest addition to its Cosmic
Wind racer line. This excellent sport model has a scale twist that
makes it eligible to fly at IMAA (International Miniature Aircraft
Association) events, and it is easy to land.
The box in which the model arrived was appealing. It showed
great pictures of the completed model so you could see exactly what
you would have sitting on your shop table in just a few days. After
examining the pictures I couldn’t wait to open the box and get a
firsthand look at what was inside.
The prepainted fiberglass fuselage was beautiful, and it was
obvious that not much work was going to be needed to get it ready to
10sig3.QXD 8/23/07 2:38 PM Page 78
October 2007 79
The fiberglass parts are finished with two-part polyurethane paint.
The wood parts are finished with MonoKote.
Underneath the builder-supplied battery tray are the receiver and
radio battery. Heavy-duty servos are recommended.
Photos by Michael Ramsey
A homemade jumper arms the power
system. The rubber band makes the plug
easy to find.
The 8 x 32 threaded rods allow the motor
to be easily adjusted for position and
thrust angle.
The female plug of a Deans connector is
spliced between the positive leads of the
battery.
The wing assembly is secured with two 1/4-
20 nylon screws, which makes battery
access quick.
The 1/8 light-plywood tray fits in a tongue at the firewall and is held down with Velcro
straps in the back. The 10S Li-Poly battery system is extremely efficient.
fly. All the formers were preinstalled, including the fuel-tank mount. I
removed that since I chose to convert this model to electric power.
The servo trays and pushrod guides were also installed. The
pushrod exits were faired into the fuselage on the tail section. I thought
this was a nice touch.
The next parts of the model I checked out were the wing halves. I
was pleased to see the nice covering job and the precut hatch covers.
There was a piece of string inside the wing halves to assist in threading
the servo leads through the wing.
The painted fiberglass cowl and wheel pants were impressive. The
latter had antirotation screw holes predrilled and blind nuts already
installed.
I was extremely pleased with all the Minnow’s parts, but I was
particularly happy with the landing gear. Its construction was sturdy,
which was great, but it was also painted.
The top of the gear was red to match the top of the airplane and the
bottom of the gear was white to match the bottom of the airplane. This
extra attention to the paint scheme completed the overall appeal when
the Minnow was complete.
As I mentioned, I converted this model to electric power. Since so
10sig3.QXD 8/23/07 2:08 PM Page 79
80 MODEL AVIATION
Pluses and Minuses
Type: Semiscale ARF
Pilot skill level: Intermediate to expert
Wingspan: 63 inches
Wing area: 775 square inches
Length: 56.5 inches
Weight: 7.25-8.25 pounds
Wing loading: 22-25 ounces/square foot
Engine: .61 two-stroke or .91 four-stroke
Radio: Four channels, five servos
Construction: Balsa, light plywood,
molded fiberglass fuselage
Covering/finish: Polyurethane paint,
MonoKote covering
Price: $219.99
Specifications
The painted fuselage matched
extraordinarily well with the trim lines of
the fiberglass cowling.
Trim the self-adhesive decals as tight as
possible for that professional appearance.
The thin airfoil offers little drag. Landing approaches are long, but the Minnow is stable
enough for a full-stall touchdown. The scale spinner is a nice touch.
Room in the stabilizer saddle is left for
shimming the horizontal stabilizer to align
with the wing.
Left: Carbon-fiber pushrods from Central
Hobbies were substituted for the aileron
linkages.
Below: The included metal pushrods offer
a solid link from the tail surfaces to the
servos under the wing.
Motor used: aero-naut actro 40-4
Propeller: APC 14 x 10-15 x 11
Radio system: Futaba 14MZ transmitter,
Futaba R319 receiver, Futaba digital
servos, 7.4-volt Li-Poly receiver battery,
6.0-volt regulator
Power system: Castle Creations
Phoenix-110HV ESC, two Tanic 5S3P
5400 mAh Li-Poly battery packs
connected in series
Output: 1,200-1,400 watts at 54-59
amps, 7,500-8,100 rpm
Ready-to-fly weight: 8 pounds
Flight duration: 10 minutes
Test-Model Details
+
• Accurate scale outline
• Beautiful fiberglass work and
painted parts
• Can easily be converted to electric
power for sport or performance
power
-• None noted
10sig3.QXD 8/23/07 2:18 PM Page 80
much work was already completed on it, it
was the perfect choice because build time was
really not increased.
I needed to determine which motor, speed
controller, and batteries would be required.
After placing a quick phone call to Hobby
Lobby I decided to use the actro 40-4 motor
(now distributed by Dymond Modelsport
Ltd.). I picked the Castle Creations Phoenix-
110HV speed controller because of the high
voltage capabilities and ease of use and setup.
The Minnow was designed to be a racer,
so I wanted the extra voltage from the 10S
pack to go to good use. A large-diameter
propeller with a deep pitch would get me the
performance that is characteristic of the
prototype.
I chose the Tanic Li-Poly batteries because
of their high C rating. Brian Nakonechny at
Tanic told me he could build two 5S3P 5400
mAh packs with the cells arranged sideways,
permitting the 20C discharge-rate packs to fit
completely in the nose. That would leave the
CG unaffected.
Once all the electric-conversion parts
arrived, it was time to decide how to mount
the motor on the firewall. I encountered my
first conversion challenge at this point. I could
not mount the short actro motor directly on
the firewall because it would not reach the
front of the cowl.
I drew on my motor-mounting experience
and decided I would need a few additional
82 MODEL AVIATION
parts: four 12-inch lengths of 8/32 threaded
rod, 12 sets of 8/32 nuts and washers, and a
solid plate of 3mm carbon fiber.
All those items were easy to get at The
Home Depot except for the carbon-fiber plate.
I ordered it online from Mach V Motorsports,
which is an automotive shop that uses carbon
fiber to make dashboards, hoods, etc.
It is important to take appropriate
precautions when working with carbon fiber.
Wear a respirator to keep the dust from
getting into your lungs and make sure to
cover your skin to minimize irritation.
I covered the carbon-fiber plate with
masking tape so I could mark the areas that
needed to be cut and drilled. I used a compass
to draw a perfect 3-inch circle on the masking
tape.
I drilled the necessary holes to mount the
motor to the plate and then drilled the holes
that were required to attach the plate to the
firewall. Once that was finished I removed the
tape and attached the plate to the motor.
I screwed the threaded rods in place and
marked the points on the firewall where the
new holes were going to have to be drilled.
Once the holes were made I attached the
motor and carbon-fiber plate to the firewall
using the 8/32 rods. I placed the cowl on the
airplane and made fine adjustments to the
threaded rods to make the spinner backplate
line up with the cowl.
With the motor installation complete, it
was time to decide where the speed controller
should go. The cowl came with holes on the
lower right cheek to allow for cooling the
head on a glow engine, so I decided to use
those to help keep the controller cool.
I drilled four holes in the nose section
(engine box) for two zip ties that would be
used to hold the controller in place. (The cowl
covered these holes, so they are invisible.)
The next step required some thought
before jumping in. The batteries had to be
installed in the Minnow’s nose because of
where the servo tray was located. To
accomplish this I had to cut out the fuel-tank
mount and install a keeper block of wood in
the nose. This would allow for a plate, with
the batteries attached, to slide under it to keep
it from moving during flight.
I made the battery plate from 3/16 birch
plywood for its strength and stiffness. I
designed the tray to go from the Minnow’s
nose back to the servo tray and to be held in
place with hook-and-loop fastener. I built
another accessory mounting plate under the
battery tray to accommodate the receiver, the
6-volt regulator, and the flight-pack battery.
I mentioned that I had the battery packs
specially built to help keep the CG in check.
This design was phenomenal. The packs were
built so one side had more cells than the other,
and this worked great by having the heavier
side to the back of the airplane and as far back
as possible on the plate. With the packs
located there, the balance was exactly where
the instruction book called for it to be.
With the airplane balanced, it was time to
set up the radio. I did this just as the
directions called for on the high and low
rates.
However, I added a twist to the setup; I
made a third high rate for the ailerons. With
all the travels and dual rates set, the last step
was to put in 30% exponential to slightly
soften everything to my liking.
With the model’s mechanical steps
complete, there were just a few finishing
touches left. This ARF came with decals.
When applied they looked great and
enhanced the Minnow’s look. Applying all
the letters was time-consuming but not too
difficult, and the outcome was well worth it.
Once all the letters were applied, I put on the
spinner and took some pictures.
At this point the Minnow was ready to test
run, and I had to make sure the amp draw was
acceptable. I turned on the transmitter
followed by the receiver in the airplane, but
even with the switch turned on the motor was
not live since the onboard safety still needed
to be plugged in.
The onboard safety consisted of a simple
jumper on the outside of the fuselage. The
model was not armed until it was plugged in.
Once the airplane was armed, it was time
to check the amps. The actro was pulling 58
amps on an APC 15 x 8E propeller. It felt like
it was going to have tons of power.
Flying: With these final tests completed, I
packed up the Minnow and headed to the
field. When I pulled into the parking area the
members started migrating to my truck to see
what new and interesting aircraft I had.
Everyone was impressed with this Great
Planes release. Many commented on the
fiberglass fuselage’s nice construction and
how well the paint and MonoKote matched. I
spent some time answering questions and
explaining how I converted the Minnow to
electric power, and then it was time to fly.
I performed a quick range and control test,
and then I released the Minnow to taxi down
the runway. At the end of the runway I
completed one last control check and then
slowly added power.
The Minnow lifted off at half power and
took to the sky. Immediately after takeoff I
could tell that it was going to fly well. After a
few clicks of up-elevator trim and one click of
right aileron trim, the model was flying level
and with hands off.
After a few passes to check the trim it was
time to play around to see what the Minnow
could do. I started with some loops and rolls
and found it to be precise. It carved through
the air extremely well—almost like an
Aerobatics airplane.
I tried some more difficult maneuvers:
Four Point Rolls, Eight Point Rolls, some
Slow Rolls. Wow! This airplane flew like it
was on rails!
I set up for landing with a nice, long
approach to allow the Minnow enough room
to slow to touchdown speed. As it rolled out
on final on a nice speed, just a hint of upelevator
was needed to raise the nose to the
proper touchdown angle.
After landing and taxiing back, I took out
the batteries to see how they were doing. I
was delighted to see the cell temperatures at
only 110°. That was great; it meant everything
was working correctly and nothing was
overheating or having to work too hard.
After determining that all the equipment
was performing perfectly, I decided to make
another flight to test the Minnow’s
performance while increasing its speed. The
second flight proved to be as exciting as the
first.
I applied half power for the takeoff, and
the model held a nice climbout angle. It did a
Split S from the climbout and headed back
down the runway, and I increased the throttle
to wide open. The model kept accelerating
down the runway. I banked it to the left like a
pylon turn, leveled it out, banked it to the left
again, and took it back to level.
The Minnow looked great and performed
extremely well at high speeds. It was graceful
and carved its way around the track.
After landing, people at the field told me
how impressed they were with the airplane. It
was quiet yet fast, a cinch to fly, and fully
aerobatic. This is a terrific model! MA
Roth Heyes
[email protected]
Manufacturer/Distributor:
Great Planes Hobby Distributors
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com
Items Used in Review:
Futaba radio equipment
www.futaba-rc.com
Castle Creations ESC
www.castlecreations.com
Tanic Li-Poly batteries
www.tanicpacks.com
Carbon-fiber plate
www.machv.com
Aero-naut actro motor
www.rc-dymond.com
Accessories
www.hobby-lobby.com
Other Review Sources:
Model Airplane News: February 2006
RCMF: February 2005 and June 2006
RC Report: December 2005
Fly RC: October 2006
Edition: Model Aviation - 2007/10
Page Numbers: 78,79,80,82,84
78 MODEL AVIATION
BY ROTH HEYES
A semiscale, IMAA-legal
model of the classic homebuilt racer
All the builder needs to supply to
complete the scale look of this
model is a pilot bust.
The Minnow is a fast mover
with electric or glow power.
Plane Talk: Great Planes Cosmic Wind Minnow ARF
Little rudder input is needed to hold the Minnow in knife-edge
flight at three-quarters throttle.
Cooling holes in the right cowl cheek are finished at the factory.
Notice the two-color painted landing gear.
THE MINNOW IS Great Planes’ newest addition to its Cosmic
Wind racer line. This excellent sport model has a scale twist that
makes it eligible to fly at IMAA (International Miniature Aircraft
Association) events, and it is easy to land.
The box in which the model arrived was appealing. It showed
great pictures of the completed model so you could see exactly what
you would have sitting on your shop table in just a few days. After
examining the pictures I couldn’t wait to open the box and get a
firsthand look at what was inside.
The prepainted fiberglass fuselage was beautiful, and it was
obvious that not much work was going to be needed to get it ready to
10sig3.QXD 8/23/07 2:38 PM Page 78
October 2007 79
The fiberglass parts are finished with two-part polyurethane paint.
The wood parts are finished with MonoKote.
Underneath the builder-supplied battery tray are the receiver and
radio battery. Heavy-duty servos are recommended.
Photos by Michael Ramsey
A homemade jumper arms the power
system. The rubber band makes the plug
easy to find.
The 8 x 32 threaded rods allow the motor
to be easily adjusted for position and
thrust angle.
The female plug of a Deans connector is
spliced between the positive leads of the
battery.
The wing assembly is secured with two 1/4-
20 nylon screws, which makes battery
access quick.
The 1/8 light-plywood tray fits in a tongue at the firewall and is held down with Velcro
straps in the back. The 10S Li-Poly battery system is extremely efficient.
fly. All the formers were preinstalled, including the fuel-tank mount. I
removed that since I chose to convert this model to electric power.
The servo trays and pushrod guides were also installed. The
pushrod exits were faired into the fuselage on the tail section. I thought
this was a nice touch.
The next parts of the model I checked out were the wing halves. I
was pleased to see the nice covering job and the precut hatch covers.
There was a piece of string inside the wing halves to assist in threading
the servo leads through the wing.
The painted fiberglass cowl and wheel pants were impressive. The
latter had antirotation screw holes predrilled and blind nuts already
installed.
I was extremely pleased with all the Minnow’s parts, but I was
particularly happy with the landing gear. Its construction was sturdy,
which was great, but it was also painted.
The top of the gear was red to match the top of the airplane and the
bottom of the gear was white to match the bottom of the airplane. This
extra attention to the paint scheme completed the overall appeal when
the Minnow was complete.
As I mentioned, I converted this model to electric power. Since so
10sig3.QXD 8/23/07 2:08 PM Page 79
80 MODEL AVIATION
Pluses and Minuses
Type: Semiscale ARF
Pilot skill level: Intermediate to expert
Wingspan: 63 inches
Wing area: 775 square inches
Length: 56.5 inches
Weight: 7.25-8.25 pounds
Wing loading: 22-25 ounces/square foot
Engine: .61 two-stroke or .91 four-stroke
Radio: Four channels, five servos
Construction: Balsa, light plywood,
molded fiberglass fuselage
Covering/finish: Polyurethane paint,
MonoKote covering
Price: $219.99
Specifications
The painted fuselage matched
extraordinarily well with the trim lines of
the fiberglass cowling.
Trim the self-adhesive decals as tight as
possible for that professional appearance.
The thin airfoil offers little drag. Landing approaches are long, but the Minnow is stable
enough for a full-stall touchdown. The scale spinner is a nice touch.
Room in the stabilizer saddle is left for
shimming the horizontal stabilizer to align
with the wing.
Left: Carbon-fiber pushrods from Central
Hobbies were substituted for the aileron
linkages.
Below: The included metal pushrods offer
a solid link from the tail surfaces to the
servos under the wing.
Motor used: aero-naut actro 40-4
Propeller: APC 14 x 10-15 x 11
Radio system: Futaba 14MZ transmitter,
Futaba R319 receiver, Futaba digital
servos, 7.4-volt Li-Poly receiver battery,
6.0-volt regulator
Power system: Castle Creations
Phoenix-110HV ESC, two Tanic 5S3P
5400 mAh Li-Poly battery packs
connected in series
Output: 1,200-1,400 watts at 54-59
amps, 7,500-8,100 rpm
Ready-to-fly weight: 8 pounds
Flight duration: 10 minutes
Test-Model Details
+
• Accurate scale outline
• Beautiful fiberglass work and
painted parts
• Can easily be converted to electric
power for sport or performance
power
-• None noted
10sig3.QXD 8/23/07 2:18 PM Page 80
much work was already completed on it, it
was the perfect choice because build time was
really not increased.
I needed to determine which motor, speed
controller, and batteries would be required.
After placing a quick phone call to Hobby
Lobby I decided to use the actro 40-4 motor
(now distributed by Dymond Modelsport
Ltd.). I picked the Castle Creations Phoenix-
110HV speed controller because of the high
voltage capabilities and ease of use and setup.
The Minnow was designed to be a racer,
so I wanted the extra voltage from the 10S
pack to go to good use. A large-diameter
propeller with a deep pitch would get me the
performance that is characteristic of the
prototype.
I chose the Tanic Li-Poly batteries because
of their high C rating. Brian Nakonechny at
Tanic told me he could build two 5S3P 5400
mAh packs with the cells arranged sideways,
permitting the 20C discharge-rate packs to fit
completely in the nose. That would leave the
CG unaffected.
Once all the electric-conversion parts
arrived, it was time to decide how to mount
the motor on the firewall. I encountered my
first conversion challenge at this point. I could
not mount the short actro motor directly on
the firewall because it would not reach the
front of the cowl.
I drew on my motor-mounting experience
and decided I would need a few additional
82 MODEL AVIATION
parts: four 12-inch lengths of 8/32 threaded
rod, 12 sets of 8/32 nuts and washers, and a
solid plate of 3mm carbon fiber.
All those items were easy to get at The
Home Depot except for the carbon-fiber plate.
I ordered it online from Mach V Motorsports,
which is an automotive shop that uses carbon
fiber to make dashboards, hoods, etc.
It is important to take appropriate
precautions when working with carbon fiber.
Wear a respirator to keep the dust from
getting into your lungs and make sure to
cover your skin to minimize irritation.
I covered the carbon-fiber plate with
masking tape so I could mark the areas that
needed to be cut and drilled. I used a compass
to draw a perfect 3-inch circle on the masking
tape.
I drilled the necessary holes to mount the
motor to the plate and then drilled the holes
that were required to attach the plate to the
firewall. Once that was finished I removed the
tape and attached the plate to the motor.
I screwed the threaded rods in place and
marked the points on the firewall where the
new holes were going to have to be drilled.
Once the holes were made I attached the
motor and carbon-fiber plate to the firewall
using the 8/32 rods. I placed the cowl on the
airplane and made fine adjustments to the
threaded rods to make the spinner backplate
line up with the cowl.
With the motor installation complete, it
was time to decide where the speed controller
should go. The cowl came with holes on the
lower right cheek to allow for cooling the
head on a glow engine, so I decided to use
those to help keep the controller cool.
I drilled four holes in the nose section
(engine box) for two zip ties that would be
used to hold the controller in place. (The cowl
covered these holes, so they are invisible.)
The next step required some thought
before jumping in. The batteries had to be
installed in the Minnow’s nose because of
where the servo tray was located. To
accomplish this I had to cut out the fuel-tank
mount and install a keeper block of wood in
the nose. This would allow for a plate, with
the batteries attached, to slide under it to keep
it from moving during flight.
I made the battery plate from 3/16 birch
plywood for its strength and stiffness. I
designed the tray to go from the Minnow’s
nose back to the servo tray and to be held in
place with hook-and-loop fastener. I built
another accessory mounting plate under the
battery tray to accommodate the receiver, the
6-volt regulator, and the flight-pack battery.
I mentioned that I had the battery packs
specially built to help keep the CG in check.
This design was phenomenal. The packs were
built so one side had more cells than the other,
and this worked great by having the heavier
side to the back of the airplane and as far back
as possible on the plate. With the packs
located there, the balance was exactly where
the instruction book called for it to be.
With the airplane balanced, it was time to
set up the radio. I did this just as the
directions called for on the high and low
rates.
However, I added a twist to the setup; I
made a third high rate for the ailerons. With
all the travels and dual rates set, the last step
was to put in 30% exponential to slightly
soften everything to my liking.
With the model’s mechanical steps
complete, there were just a few finishing
touches left. This ARF came with decals.
When applied they looked great and
enhanced the Minnow’s look. Applying all
the letters was time-consuming but not too
difficult, and the outcome was well worth it.
Once all the letters were applied, I put on the
spinner and took some pictures.
At this point the Minnow was ready to test
run, and I had to make sure the amp draw was
acceptable. I turned on the transmitter
followed by the receiver in the airplane, but
even with the switch turned on the motor was
not live since the onboard safety still needed
to be plugged in.
The onboard safety consisted of a simple
jumper on the outside of the fuselage. The
model was not armed until it was plugged in.
Once the airplane was armed, it was time
to check the amps. The actro was pulling 58
amps on an APC 15 x 8E propeller. It felt like
it was going to have tons of power.
Flying: With these final tests completed, I
packed up the Minnow and headed to the
field. When I pulled into the parking area the
members started migrating to my truck to see
what new and interesting aircraft I had.
Everyone was impressed with this Great
Planes release. Many commented on the
fiberglass fuselage’s nice construction and
how well the paint and MonoKote matched. I
spent some time answering questions and
explaining how I converted the Minnow to
electric power, and then it was time to fly.
I performed a quick range and control test,
and then I released the Minnow to taxi down
the runway. At the end of the runway I
completed one last control check and then
slowly added power.
The Minnow lifted off at half power and
took to the sky. Immediately after takeoff I
could tell that it was going to fly well. After a
few clicks of up-elevator trim and one click of
right aileron trim, the model was flying level
and with hands off.
After a few passes to check the trim it was
time to play around to see what the Minnow
could do. I started with some loops and rolls
and found it to be precise. It carved through
the air extremely well—almost like an
Aerobatics airplane.
I tried some more difficult maneuvers:
Four Point Rolls, Eight Point Rolls, some
Slow Rolls. Wow! This airplane flew like it
was on rails!
I set up for landing with a nice, long
approach to allow the Minnow enough room
to slow to touchdown speed. As it rolled out
on final on a nice speed, just a hint of upelevator
was needed to raise the nose to the
proper touchdown angle.
After landing and taxiing back, I took out
the batteries to see how they were doing. I
was delighted to see the cell temperatures at
only 110°. That was great; it meant everything
was working correctly and nothing was
overheating or having to work too hard.
After determining that all the equipment
was performing perfectly, I decided to make
another flight to test the Minnow’s
performance while increasing its speed. The
second flight proved to be as exciting as the
first.
I applied half power for the takeoff, and
the model held a nice climbout angle. It did a
Split S from the climbout and headed back
down the runway, and I increased the throttle
to wide open. The model kept accelerating
down the runway. I banked it to the left like a
pylon turn, leveled it out, banked it to the left
again, and took it back to level.
The Minnow looked great and performed
extremely well at high speeds. It was graceful
and carved its way around the track.
After landing, people at the field told me
how impressed they were with the airplane. It
was quiet yet fast, a cinch to fly, and fully
aerobatic. This is a terrific model! MA
Roth Heyes
[email protected]
Manufacturer/Distributor:
Great Planes Hobby Distributors
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com
Items Used in Review:
Futaba radio equipment
www.futaba-rc.com
Castle Creations ESC
www.castlecreations.com
Tanic Li-Poly batteries
www.tanicpacks.com
Carbon-fiber plate
www.machv.com
Aero-naut actro motor
www.rc-dymond.com
Accessories
www.hobby-lobby.com
Other Review Sources:
Model Airplane News: February 2006
RCMF: February 2005 and June 2006
RC Report: December 2005
Fly RC: October 2006
Edition: Model Aviation - 2007/10
Page Numbers: 78,79,80,82,84
78 MODEL AVIATION
BY ROTH HEYES
A semiscale, IMAA-legal
model of the classic homebuilt racer
All the builder needs to supply to
complete the scale look of this
model is a pilot bust.
The Minnow is a fast mover
with electric or glow power.
Plane Talk: Great Planes Cosmic Wind Minnow ARF
Little rudder input is needed to hold the Minnow in knife-edge
flight at three-quarters throttle.
Cooling holes in the right cowl cheek are finished at the factory.
Notice the two-color painted landing gear.
THE MINNOW IS Great Planes’ newest addition to its Cosmic
Wind racer line. This excellent sport model has a scale twist that
makes it eligible to fly at IMAA (International Miniature Aircraft
Association) events, and it is easy to land.
The box in which the model arrived was appealing. It showed
great pictures of the completed model so you could see exactly what
you would have sitting on your shop table in just a few days. After
examining the pictures I couldn’t wait to open the box and get a
firsthand look at what was inside.
The prepainted fiberglass fuselage was beautiful, and it was
obvious that not much work was going to be needed to get it ready to
10sig3.QXD 8/23/07 2:38 PM Page 78
October 2007 79
The fiberglass parts are finished with two-part polyurethane paint.
The wood parts are finished with MonoKote.
Underneath the builder-supplied battery tray are the receiver and
radio battery. Heavy-duty servos are recommended.
Photos by Michael Ramsey
A homemade jumper arms the power
system. The rubber band makes the plug
easy to find.
The 8 x 32 threaded rods allow the motor
to be easily adjusted for position and
thrust angle.
The female plug of a Deans connector is
spliced between the positive leads of the
battery.
The wing assembly is secured with two 1/4-
20 nylon screws, which makes battery
access quick.
The 1/8 light-plywood tray fits in a tongue at the firewall and is held down with Velcro
straps in the back. The 10S Li-Poly battery system is extremely efficient.
fly. All the formers were preinstalled, including the fuel-tank mount. I
removed that since I chose to convert this model to electric power.
The servo trays and pushrod guides were also installed. The
pushrod exits were faired into the fuselage on the tail section. I thought
this was a nice touch.
The next parts of the model I checked out were the wing halves. I
was pleased to see the nice covering job and the precut hatch covers.
There was a piece of string inside the wing halves to assist in threading
the servo leads through the wing.
The painted fiberglass cowl and wheel pants were impressive. The
latter had antirotation screw holes predrilled and blind nuts already
installed.
I was extremely pleased with all the Minnow’s parts, but I was
particularly happy with the landing gear. Its construction was sturdy,
which was great, but it was also painted.
The top of the gear was red to match the top of the airplane and the
bottom of the gear was white to match the bottom of the airplane. This
extra attention to the paint scheme completed the overall appeal when
the Minnow was complete.
As I mentioned, I converted this model to electric power. Since so
10sig3.QXD 8/23/07 2:08 PM Page 79
80 MODEL AVIATION
Pluses and Minuses
Type: Semiscale ARF
Pilot skill level: Intermediate to expert
Wingspan: 63 inches
Wing area: 775 square inches
Length: 56.5 inches
Weight: 7.25-8.25 pounds
Wing loading: 22-25 ounces/square foot
Engine: .61 two-stroke or .91 four-stroke
Radio: Four channels, five servos
Construction: Balsa, light plywood,
molded fiberglass fuselage
Covering/finish: Polyurethane paint,
MonoKote covering
Price: $219.99
Specifications
The painted fuselage matched
extraordinarily well with the trim lines of
the fiberglass cowling.
Trim the self-adhesive decals as tight as
possible for that professional appearance.
The thin airfoil offers little drag. Landing approaches are long, but the Minnow is stable
enough for a full-stall touchdown. The scale spinner is a nice touch.
Room in the stabilizer saddle is left for
shimming the horizontal stabilizer to align
with the wing.
Left: Carbon-fiber pushrods from Central
Hobbies were substituted for the aileron
linkages.
Below: The included metal pushrods offer
a solid link from the tail surfaces to the
servos under the wing.
Motor used: aero-naut actro 40-4
Propeller: APC 14 x 10-15 x 11
Radio system: Futaba 14MZ transmitter,
Futaba R319 receiver, Futaba digital
servos, 7.4-volt Li-Poly receiver battery,
6.0-volt regulator
Power system: Castle Creations
Phoenix-110HV ESC, two Tanic 5S3P
5400 mAh Li-Poly battery packs
connected in series
Output: 1,200-1,400 watts at 54-59
amps, 7,500-8,100 rpm
Ready-to-fly weight: 8 pounds
Flight duration: 10 minutes
Test-Model Details
+
• Accurate scale outline
• Beautiful fiberglass work and
painted parts
• Can easily be converted to electric
power for sport or performance
power
-• None noted
10sig3.QXD 8/23/07 2:18 PM Page 80
much work was already completed on it, it
was the perfect choice because build time was
really not increased.
I needed to determine which motor, speed
controller, and batteries would be required.
After placing a quick phone call to Hobby
Lobby I decided to use the actro 40-4 motor
(now distributed by Dymond Modelsport
Ltd.). I picked the Castle Creations Phoenix-
110HV speed controller because of the high
voltage capabilities and ease of use and setup.
The Minnow was designed to be a racer,
so I wanted the extra voltage from the 10S
pack to go to good use. A large-diameter
propeller with a deep pitch would get me the
performance that is characteristic of the
prototype.
I chose the Tanic Li-Poly batteries because
of their high C rating. Brian Nakonechny at
Tanic told me he could build two 5S3P 5400
mAh packs with the cells arranged sideways,
permitting the 20C discharge-rate packs to fit
completely in the nose. That would leave the
CG unaffected.
Once all the electric-conversion parts
arrived, it was time to decide how to mount
the motor on the firewall. I encountered my
first conversion challenge at this point. I could
not mount the short actro motor directly on
the firewall because it would not reach the
front of the cowl.
I drew on my motor-mounting experience
and decided I would need a few additional
82 MODEL AVIATION
parts: four 12-inch lengths of 8/32 threaded
rod, 12 sets of 8/32 nuts and washers, and a
solid plate of 3mm carbon fiber.
All those items were easy to get at The
Home Depot except for the carbon-fiber plate.
I ordered it online from Mach V Motorsports,
which is an automotive shop that uses carbon
fiber to make dashboards, hoods, etc.
It is important to take appropriate
precautions when working with carbon fiber.
Wear a respirator to keep the dust from
getting into your lungs and make sure to
cover your skin to minimize irritation.
I covered the carbon-fiber plate with
masking tape so I could mark the areas that
needed to be cut and drilled. I used a compass
to draw a perfect 3-inch circle on the masking
tape.
I drilled the necessary holes to mount the
motor to the plate and then drilled the holes
that were required to attach the plate to the
firewall. Once that was finished I removed the
tape and attached the plate to the motor.
I screwed the threaded rods in place and
marked the points on the firewall where the
new holes were going to have to be drilled.
Once the holes were made I attached the
motor and carbon-fiber plate to the firewall
using the 8/32 rods. I placed the cowl on the
airplane and made fine adjustments to the
threaded rods to make the spinner backplate
line up with the cowl.
With the motor installation complete, it
was time to decide where the speed controller
should go. The cowl came with holes on the
lower right cheek to allow for cooling the
head on a glow engine, so I decided to use
those to help keep the controller cool.
I drilled four holes in the nose section
(engine box) for two zip ties that would be
used to hold the controller in place. (The cowl
covered these holes, so they are invisible.)
The next step required some thought
before jumping in. The batteries had to be
installed in the Minnow’s nose because of
where the servo tray was located. To
accomplish this I had to cut out the fuel-tank
mount and install a keeper block of wood in
the nose. This would allow for a plate, with
the batteries attached, to slide under it to keep
it from moving during flight.
I made the battery plate from 3/16 birch
plywood for its strength and stiffness. I
designed the tray to go from the Minnow’s
nose back to the servo tray and to be held in
place with hook-and-loop fastener. I built
another accessory mounting plate under the
battery tray to accommodate the receiver, the
6-volt regulator, and the flight-pack battery.
I mentioned that I had the battery packs
specially built to help keep the CG in check.
This design was phenomenal. The packs were
built so one side had more cells than the other,
and this worked great by having the heavier
side to the back of the airplane and as far back
as possible on the plate. With the packs
located there, the balance was exactly where
the instruction book called for it to be.
With the airplane balanced, it was time to
set up the radio. I did this just as the
directions called for on the high and low
rates.
However, I added a twist to the setup; I
made a third high rate for the ailerons. With
all the travels and dual rates set, the last step
was to put in 30% exponential to slightly
soften everything to my liking.
With the model’s mechanical steps
complete, there were just a few finishing
touches left. This ARF came with decals.
When applied they looked great and
enhanced the Minnow’s look. Applying all
the letters was time-consuming but not too
difficult, and the outcome was well worth it.
Once all the letters were applied, I put on the
spinner and took some pictures.
At this point the Minnow was ready to test
run, and I had to make sure the amp draw was
acceptable. I turned on the transmitter
followed by the receiver in the airplane, but
even with the switch turned on the motor was
not live since the onboard safety still needed
to be plugged in.
The onboard safety consisted of a simple
jumper on the outside of the fuselage. The
model was not armed until it was plugged in.
Once the airplane was armed, it was time
to check the amps. The actro was pulling 58
amps on an APC 15 x 8E propeller. It felt like
it was going to have tons of power.
Flying: With these final tests completed, I
packed up the Minnow and headed to the
field. When I pulled into the parking area the
members started migrating to my truck to see
what new and interesting aircraft I had.
Everyone was impressed with this Great
Planes release. Many commented on the
fiberglass fuselage’s nice construction and
how well the paint and MonoKote matched. I
spent some time answering questions and
explaining how I converted the Minnow to
electric power, and then it was time to fly.
I performed a quick range and control test,
and then I released the Minnow to taxi down
the runway. At the end of the runway I
completed one last control check and then
slowly added power.
The Minnow lifted off at half power and
took to the sky. Immediately after takeoff I
could tell that it was going to fly well. After a
few clicks of up-elevator trim and one click of
right aileron trim, the model was flying level
and with hands off.
After a few passes to check the trim it was
time to play around to see what the Minnow
could do. I started with some loops and rolls
and found it to be precise. It carved through
the air extremely well—almost like an
Aerobatics airplane.
I tried some more difficult maneuvers:
Four Point Rolls, Eight Point Rolls, some
Slow Rolls. Wow! This airplane flew like it
was on rails!
I set up for landing with a nice, long
approach to allow the Minnow enough room
to slow to touchdown speed. As it rolled out
on final on a nice speed, just a hint of upelevator
was needed to raise the nose to the
proper touchdown angle.
After landing and taxiing back, I took out
the batteries to see how they were doing. I
was delighted to see the cell temperatures at
only 110°. That was great; it meant everything
was working correctly and nothing was
overheating or having to work too hard.
After determining that all the equipment
was performing perfectly, I decided to make
another flight to test the Minnow’s
performance while increasing its speed. The
second flight proved to be as exciting as the
first.
I applied half power for the takeoff, and
the model held a nice climbout angle. It did a
Split S from the climbout and headed back
down the runway, and I increased the throttle
to wide open. The model kept accelerating
down the runway. I banked it to the left like a
pylon turn, leveled it out, banked it to the left
again, and took it back to level.
The Minnow looked great and performed
extremely well at high speeds. It was graceful
and carved its way around the track.
After landing, people at the field told me
how impressed they were with the airplane. It
was quiet yet fast, a cinch to fly, and fully
aerobatic. This is a terrific model! MA
Roth Heyes
[email protected]
Manufacturer/Distributor:
Great Planes Hobby Distributors
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com
Items Used in Review:
Futaba radio equipment
www.futaba-rc.com
Castle Creations ESC
www.castlecreations.com
Tanic Li-Poly batteries
www.tanicpacks.com
Carbon-fiber plate
www.machv.com
Aero-naut actro motor
www.rc-dymond.com
Accessories
www.hobby-lobby.com
Other Review Sources:
Model Airplane News: February 2006
RCMF: February 2005 and June 2006
RC Report: December 2005
Fly RC: October 2006