I enjoy making unique—and often unusual—airplanes.
Occasionally roaming away from the herd sustains my
interest in this hobby. Often, a project will evolve in my
head as a generic concept, rather than a well-defined end
product.
I may wake up in the middle of the night with the sudden
urge to build a trimotor airplane, perhaps an autogyro, or
maybe even a three-engine autogyro. To give my visions a
jump start and ensure that they are built, I attempt to find
off-the-shelf components to use—aka kitbashing. Whether it’s
the fuselage from a model I pranged three years ago, or a spare
wing from the clearance bin at the hobby shop, it’s all fair
game if I think it will expedite the project.
Sometimes, a good deal on airframe parts encourages me to
stock up for future projects. Having those parts and thinking,
“what if?” becomes the catalyst for a new endeavor.
I recently discovered a good deal on airframe parts for the
Flyzone Red Hawk, a discontinued beginner’s airplane. In stock
form, the Red Hawk uses a 380-size brushed motor, Ni-Cd
batteries, and a simplified V-tail control arrangement.
From a kitbashing standpoint, this left me with plenty of
latitude for alternate power systems and control methods.
A flood of ideas with varying levels of practicality and sanity
began pouring from my brain, so I purchased an armful of
wings and fuselages with which to tinker.
Red Hawk Kitbash #1—The Modernization
Because I had never flown a stock Red Hawk, I wanted my
first project to provide a baseline of the airplane’s performance
envelope. This knowledge would help me determine how
and when to use Red Hawk parts for subsequent projects.
Although my Red Hawk would cast a virtually identical
shadow as a stock version, I decided to equip it with a modern
power system and high-quality radio gear.
The pod-and-boom fuselage comes with an integrated
mount for V-tail control surfaces. I didn’t have any of the stock V-tail parts, so I cut new ones from 5mm Midwest Products
Cellfoam 88 sheet foam, allowing me to make the control
surfaces as large as I wanted. I used a low-temperature glue
gun to secure the surfaces to the mount.
To actuate the V-tail, I installed a Futaba S3114 microservo
on each side of the fuselage pod. I found that the soft, plastic
fuselage easily cuts with a few strokes of a hobby knife. The
servos are connected to the control surfaces with flexible
pushrods. Hot glue holds the pushrod sleeves to the airframe.
For power, I used an ElectriFly Rimfire 250 outrunner
motor. I attached it directly to the existing plastic firewall using
three 2 x 3/8-inch screws. The Rimfire motor is nearly 2 ounces
lighter and more efficient than the can motor it replaces.
An ElectriFly 8-amp ESC, a GWS 6 x 3 propeller, and 3S
800mAh LiPo batteries from various manufacturers, round out
the power system.
My completed model weighs 11.3 ounces ready to fly— a
full 33% lighter than the advertised 16.9 ounces. After you
factor in the power increase from the brushless motor system
and the oversized control surfaces, the numbers indicate that
this tame trainer just got sportier.
Takeoffs happen in mere inches, and the Red Hawk will
easily sustain a vertical climbout. If you throttle back, the
airplane will slow to a crawl. I usually use half throttle or less.
This allows me to do waist-high Figure Eights with a touchand-
go between turnarounds. Loops are no problem, but
inverted flight is tricky.
What surprised me most about the Red Hawk was its
superb glide performance. My modernized Red Hawk is as
much fun as I’ve ever had without ailerons.
Red Hawk Kitbash #2—Seeing Double
After I had proven the soundness of the Red Hawk’s basic
design with my first project, I decided to get more exotic. My
second Red Hawk iteration is a twin created by joining two
fuselages and an extended wing. I thought this version strayed
too far to keep its Red Hawk moniker, so I renamed it JATH
(Joined at the Hip).
To create an enlarged wing, I split
one wing in half and spliced in the
center section of another wing. This
increased the span by 14 inches and
placed the wing joints at the fuselage
saddles (where they wouldn’t be prone
to twisting). I removed the individual
carbon-fi ber spars from each wing
section and glued in a single spar that
spanned all three panels.
To rigidly join the two fuselages, I
utilized two sections of arrow shaft. I
drilled holes slightly smaller than the
outer diameter of the shaft in each
fuselage. I then pushed the shafts into
the holes with a twisting motion. I
added Goop adhesive to every shaft/
fuselage joint that I could reach. The
resulting structure is surprisingly rigid.
For control, I used an inverted
V-tail arrangement. A Hitec HS-55
micro servo in each fuselage pod
actuates its respective half of the
V-tail. Initially, I built the V-tail using
the leftover wingtip sections from the
wing modifi cation. I liked the surface’s
curved look and built-in red fi nish.
However, I later discarded these parts
for reasons I’ll divulge later.
To prove that brushed motors
are still a valid option, I used 6-volt
Speed-400 engines with Gunther
push-on propellers. Anyone who fl ew
electrics at the turn of the century
should be feeling a twinge of nostalgia
at the mention of this combination.
Each motor has its own E-fl ite 20-amp
ESC and 2S 1300 mAh LiPo battery.
I placed the Futaba R617FS receiver
in the right fuselage. The forward
arrow shaft doubles as a conduit for the
wires, from the port servo and ESC to
the receiver.
To provide some measure of ground
handling, I set up a differential-throttle
mix on my Futaba 7C transmitter. This
allows me to individually control each
motor with rudder inputs. Although not
as precise as a steerable tailwheel, it is
simple and works well.
The twin’s fi rst fl ight was made before
the landing gear was installed. As soon
as the airplane was launched, it showed
signs of lateral instability. The most
prominent indication was a signifi cant
Dutch Roll (unintentional yawing and
wing rocking).
The airplane was sensitive in pitch.
After nursing it around in the sky for
a few minutes, I brought JATH down
without damage.
Back in the shop, I added 1.5 ounces
of lead to the noses and installed
landing gear. These
changes moved the
CG forward, which I
believed would cure
the pitch sensitivity.
I was optimistic that
the Dutch Roll would
also disappear. On the
second fl ight, the pitch
problems were gone,
but the Dutch Roll
persisted.
Through no fault of
the airplane, I ended the second fl ight
with an unintentional spiral to the
ground. The damage was superfi cial and
easily repaired.
On my next trip back to the shop, I
replaced the original V-tail parts with
lighter Cellfoam 88 duplicates and
added separate vertical stabilizers (does
that make it a W-tail?). This moved the
CG farther forward, while (presumably)
improving lateral stability.
JATH’s third fl ight showed that the
vertical stabilizers cured the Dutch Roll
and made the airplane more pleasant
to fl y. It looks cool in the air and it’s
satisfying to see the direct cause-andeffect
of simple changes, such as the
addition of the vertical area.
Red Hawk Kitbash #3—
Uncharted Ground
For my third Red Hawk-themed
project, I wanted to do something I’ve
never attempted and that I didn’t fully
understand: asymmetry.
There are few full-scale asymmetric
aircraft to analyze. However, the two
prime examples of asymmetry, the
Blohm und Voss Bv 141 and the Rutan
Model 202 Boomerang, have good
handling qualities. There must be some
engineering logic behind these abstractlooking
aircraft.
I was unable to fi nd any useful
information about asymmetric design
philosophies in my model design
books, online, or even my Stability and
Control textbooks. I resorted to studying
three-view drawings of the Bv 141 and
Boomerang.
As I poured over the drawings, they
revealed a few secrets that made these
aircraft seem less radical than before.
I didn’t grasp every aspect of their
asymmetry, but I became confi dent
enough to believe that I could create
a fl yable asymmetric model using Red
Hawk parts.
The name for my model was obvious:
Miss Aligned. Other than its pusher
motor, Miss Aligned resembled the
layout of the Bv 141 in many ways.
Like JATH, the pods are joined with
arrow shafts. Rather than having two
identical cockpit-like pods out front,
I reworked the left pod to include a
Gatling gun and a huge cannon.
My goal was to get the airplane’s
lateral balance slightly right of the left
pod. This makes the position of the
single motor (mounted in the left pod)
have the same torque-canceling effect as
the right thrust that is incorporated into
many conventional airplanes.
The power system is the same as that
which I used on Kitbash #1. All of the
components, except the battery, were
placed in the left pod. The battery is
in the right pod with a wire extension
running through the forward arrow
shaft.
I underestimated
the balancing effect
of having the battery
in the right pod.
To shift the lateral
balance closer to the
left pod, I added .4
ounces of lead to
the left wingtip. This
placed the lateral
balance point 5/8 inch to the right of the
left pod, which, by no coincidence, is the
same location as the midpoints of the
wing and landing gear.
I was mostly sure that Miss Aligned
would fl y, but I was prepared to deal
with unexpected idiosyncrasies. I was
amazed when I began the fi rst takeoff
roll and needed no rudder input to keep
it on a straight path. The airplane lifted
off quickly and behaved normally.
The throttle/yaw coupling that I
expected never materialized. Neither
did the pitch/roll coupling I anticipated
from the off-center elevator. In short,
Miss Aligned’s predictability in fl ight
belies its quirky appearance.
What’s Next
I now have three practical airplanes
to enjoy. Kitbash #1 has joined my fleet
of utilitarian, stress-free, fly-anytime
airplanes. I like the way JATH flies, so I
plan to hang onto it and maybe install
brushless motors. Miss Aligned is a
gateway. My success with this project
has demystified asymmetric aircraft
for me and encouraged me to begin
planning a larger, more refined model
from the ground up.
If you’ll recall, my original point was
to illustrate how kitbashing off-theshelf
airframe components can both
expedite and inspire unique projects. My
combined shop time for all three of the
kitbash projects was roughly 10 hours—
much less time than it would have taken
me to scratch-build one model.
I explored these ideas with minimal
time and monetary investments. Projects
requiring too much of either resource
tend to dampen my audacity.
The next time modeling inspiration
strikes you in the middle of the night,
don’t go back to sleep. Find some
premade components and make that
aeronautical dream a reality.
Edition: Model Aviation - 2012/08
Page Numbers: 30,31,32,33,34
Edition: Model Aviation - 2012/08
Page Numbers: 30,31,32,33,34
I enjoy making unique—and often unusual—airplanes.
Occasionally roaming away from the herd sustains my
interest in this hobby. Often, a project will evolve in my
head as a generic concept, rather than a well-defined end
product.
I may wake up in the middle of the night with the sudden
urge to build a trimotor airplane, perhaps an autogyro, or
maybe even a three-engine autogyro. To give my visions a
jump start and ensure that they are built, I attempt to find
off-the-shelf components to use—aka kitbashing. Whether it’s
the fuselage from a model I pranged three years ago, or a spare
wing from the clearance bin at the hobby shop, it’s all fair
game if I think it will expedite the project.
Sometimes, a good deal on airframe parts encourages me to
stock up for future projects. Having those parts and thinking,
“what if?” becomes the catalyst for a new endeavor.
I recently discovered a good deal on airframe parts for the
Flyzone Red Hawk, a discontinued beginner’s airplane. In stock
form, the Red Hawk uses a 380-size brushed motor, Ni-Cd
batteries, and a simplified V-tail control arrangement.
From a kitbashing standpoint, this left me with plenty of
latitude for alternate power systems and control methods.
A flood of ideas with varying levels of practicality and sanity
began pouring from my brain, so I purchased an armful of
wings and fuselages with which to tinker.
Red Hawk Kitbash #1—The Modernization
Because I had never flown a stock Red Hawk, I wanted my
first project to provide a baseline of the airplane’s performance
envelope. This knowledge would help me determine how
and when to use Red Hawk parts for subsequent projects.
Although my Red Hawk would cast a virtually identical
shadow as a stock version, I decided to equip it with a modern
power system and high-quality radio gear.
The pod-and-boom fuselage comes with an integrated
mount for V-tail control surfaces. I didn’t have any of the stock V-tail parts, so I cut new ones from 5mm Midwest Products
Cellfoam 88 sheet foam, allowing me to make the control
surfaces as large as I wanted. I used a low-temperature glue
gun to secure the surfaces to the mount.
To actuate the V-tail, I installed a Futaba S3114 microservo
on each side of the fuselage pod. I found that the soft, plastic
fuselage easily cuts with a few strokes of a hobby knife. The
servos are connected to the control surfaces with flexible
pushrods. Hot glue holds the pushrod sleeves to the airframe.
For power, I used an ElectriFly Rimfire 250 outrunner
motor. I attached it directly to the existing plastic firewall using
three 2 x 3/8-inch screws. The Rimfire motor is nearly 2 ounces
lighter and more efficient than the can motor it replaces.
An ElectriFly 8-amp ESC, a GWS 6 x 3 propeller, and 3S
800mAh LiPo batteries from various manufacturers, round out
the power system.
My completed model weighs 11.3 ounces ready to fly— a
full 33% lighter than the advertised 16.9 ounces. After you
factor in the power increase from the brushless motor system
and the oversized control surfaces, the numbers indicate that
this tame trainer just got sportier.
Takeoffs happen in mere inches, and the Red Hawk will
easily sustain a vertical climbout. If you throttle back, the
airplane will slow to a crawl. I usually use half throttle or less.
This allows me to do waist-high Figure Eights with a touchand-
go between turnarounds. Loops are no problem, but
inverted flight is tricky.
What surprised me most about the Red Hawk was its
superb glide performance. My modernized Red Hawk is as
much fun as I’ve ever had without ailerons.
Red Hawk Kitbash #2—Seeing Double
After I had proven the soundness of the Red Hawk’s basic
design with my first project, I decided to get more exotic. My
second Red Hawk iteration is a twin created by joining two
fuselages and an extended wing. I thought this version strayed
too far to keep its Red Hawk moniker, so I renamed it JATH
(Joined at the Hip).
To create an enlarged wing, I split
one wing in half and spliced in the
center section of another wing. This
increased the span by 14 inches and
placed the wing joints at the fuselage
saddles (where they wouldn’t be prone
to twisting). I removed the individual
carbon-fi ber spars from each wing
section and glued in a single spar that
spanned all three panels.
To rigidly join the two fuselages, I
utilized two sections of arrow shaft. I
drilled holes slightly smaller than the
outer diameter of the shaft in each
fuselage. I then pushed the shafts into
the holes with a twisting motion. I
added Goop adhesive to every shaft/
fuselage joint that I could reach. The
resulting structure is surprisingly rigid.
For control, I used an inverted
V-tail arrangement. A Hitec HS-55
micro servo in each fuselage pod
actuates its respective half of the
V-tail. Initially, I built the V-tail using
the leftover wingtip sections from the
wing modifi cation. I liked the surface’s
curved look and built-in red fi nish.
However, I later discarded these parts
for reasons I’ll divulge later.
To prove that brushed motors
are still a valid option, I used 6-volt
Speed-400 engines with Gunther
push-on propellers. Anyone who fl ew
electrics at the turn of the century
should be feeling a twinge of nostalgia
at the mention of this combination.
Each motor has its own E-fl ite 20-amp
ESC and 2S 1300 mAh LiPo battery.
I placed the Futaba R617FS receiver
in the right fuselage. The forward
arrow shaft doubles as a conduit for the
wires, from the port servo and ESC to
the receiver.
To provide some measure of ground
handling, I set up a differential-throttle
mix on my Futaba 7C transmitter. This
allows me to individually control each
motor with rudder inputs. Although not
as precise as a steerable tailwheel, it is
simple and works well.
The twin’s fi rst fl ight was made before
the landing gear was installed. As soon
as the airplane was launched, it showed
signs of lateral instability. The most
prominent indication was a signifi cant
Dutch Roll (unintentional yawing and
wing rocking).
The airplane was sensitive in pitch.
After nursing it around in the sky for
a few minutes, I brought JATH down
without damage.
Back in the shop, I added 1.5 ounces
of lead to the noses and installed
landing gear. These
changes moved the
CG forward, which I
believed would cure
the pitch sensitivity.
I was optimistic that
the Dutch Roll would
also disappear. On the
second fl ight, the pitch
problems were gone,
but the Dutch Roll
persisted.
Through no fault of
the airplane, I ended the second fl ight
with an unintentional spiral to the
ground. The damage was superfi cial and
easily repaired.
On my next trip back to the shop, I
replaced the original V-tail parts with
lighter Cellfoam 88 duplicates and
added separate vertical stabilizers (does
that make it a W-tail?). This moved the
CG farther forward, while (presumably)
improving lateral stability.
JATH’s third fl ight showed that the
vertical stabilizers cured the Dutch Roll
and made the airplane more pleasant
to fl y. It looks cool in the air and it’s
satisfying to see the direct cause-andeffect
of simple changes, such as the
addition of the vertical area.
Red Hawk Kitbash #3—
Uncharted Ground
For my third Red Hawk-themed
project, I wanted to do something I’ve
never attempted and that I didn’t fully
understand: asymmetry.
There are few full-scale asymmetric
aircraft to analyze. However, the two
prime examples of asymmetry, the
Blohm und Voss Bv 141 and the Rutan
Model 202 Boomerang, have good
handling qualities. There must be some
engineering logic behind these abstractlooking
aircraft.
I was unable to fi nd any useful
information about asymmetric design
philosophies in my model design
books, online, or even my Stability and
Control textbooks. I resorted to studying
three-view drawings of the Bv 141 and
Boomerang.
As I poured over the drawings, they
revealed a few secrets that made these
aircraft seem less radical than before.
I didn’t grasp every aspect of their
asymmetry, but I became confi dent
enough to believe that I could create
a fl yable asymmetric model using Red
Hawk parts.
The name for my model was obvious:
Miss Aligned. Other than its pusher
motor, Miss Aligned resembled the
layout of the Bv 141 in many ways.
Like JATH, the pods are joined with
arrow shafts. Rather than having two
identical cockpit-like pods out front,
I reworked the left pod to include a
Gatling gun and a huge cannon.
My goal was to get the airplane’s
lateral balance slightly right of the left
pod. This makes the position of the
single motor (mounted in the left pod)
have the same torque-canceling effect as
the right thrust that is incorporated into
many conventional airplanes.
The power system is the same as that
which I used on Kitbash #1. All of the
components, except the battery, were
placed in the left pod. The battery is
in the right pod with a wire extension
running through the forward arrow
shaft.
I underestimated
the balancing effect
of having the battery
in the right pod.
To shift the lateral
balance closer to the
left pod, I added .4
ounces of lead to
the left wingtip. This
placed the lateral
balance point 5/8 inch to the right of the
left pod, which, by no coincidence, is the
same location as the midpoints of the
wing and landing gear.
I was mostly sure that Miss Aligned
would fl y, but I was prepared to deal
with unexpected idiosyncrasies. I was
amazed when I began the fi rst takeoff
roll and needed no rudder input to keep
it on a straight path. The airplane lifted
off quickly and behaved normally.
The throttle/yaw coupling that I
expected never materialized. Neither
did the pitch/roll coupling I anticipated
from the off-center elevator. In short,
Miss Aligned’s predictability in fl ight
belies its quirky appearance.
What’s Next
I now have three practical airplanes
to enjoy. Kitbash #1 has joined my fleet
of utilitarian, stress-free, fly-anytime
airplanes. I like the way JATH flies, so I
plan to hang onto it and maybe install
brushless motors. Miss Aligned is a
gateway. My success with this project
has demystified asymmetric aircraft
for me and encouraged me to begin
planning a larger, more refined model
from the ground up.
If you’ll recall, my original point was
to illustrate how kitbashing off-theshelf
airframe components can both
expedite and inspire unique projects. My
combined shop time for all three of the
kitbash projects was roughly 10 hours—
much less time than it would have taken
me to scratch-build one model.
I explored these ideas with minimal
time and monetary investments. Projects
requiring too much of either resource
tend to dampen my audacity.
The next time modeling inspiration
strikes you in the middle of the night,
don’t go back to sleep. Find some
premade components and make that
aeronautical dream a reality.
Edition: Model Aviation - 2012/08
Page Numbers: 30,31,32,33,34
I enjoy making unique—and often unusual—airplanes.
Occasionally roaming away from the herd sustains my
interest in this hobby. Often, a project will evolve in my
head as a generic concept, rather than a well-defined end
product.
I may wake up in the middle of the night with the sudden
urge to build a trimotor airplane, perhaps an autogyro, or
maybe even a three-engine autogyro. To give my visions a
jump start and ensure that they are built, I attempt to find
off-the-shelf components to use—aka kitbashing. Whether it’s
the fuselage from a model I pranged three years ago, or a spare
wing from the clearance bin at the hobby shop, it’s all fair
game if I think it will expedite the project.
Sometimes, a good deal on airframe parts encourages me to
stock up for future projects. Having those parts and thinking,
“what if?” becomes the catalyst for a new endeavor.
I recently discovered a good deal on airframe parts for the
Flyzone Red Hawk, a discontinued beginner’s airplane. In stock
form, the Red Hawk uses a 380-size brushed motor, Ni-Cd
batteries, and a simplified V-tail control arrangement.
From a kitbashing standpoint, this left me with plenty of
latitude for alternate power systems and control methods.
A flood of ideas with varying levels of practicality and sanity
began pouring from my brain, so I purchased an armful of
wings and fuselages with which to tinker.
Red Hawk Kitbash #1—The Modernization
Because I had never flown a stock Red Hawk, I wanted my
first project to provide a baseline of the airplane’s performance
envelope. This knowledge would help me determine how
and when to use Red Hawk parts for subsequent projects.
Although my Red Hawk would cast a virtually identical
shadow as a stock version, I decided to equip it with a modern
power system and high-quality radio gear.
The pod-and-boom fuselage comes with an integrated
mount for V-tail control surfaces. I didn’t have any of the stock V-tail parts, so I cut new ones from 5mm Midwest Products
Cellfoam 88 sheet foam, allowing me to make the control
surfaces as large as I wanted. I used a low-temperature glue
gun to secure the surfaces to the mount.
To actuate the V-tail, I installed a Futaba S3114 microservo
on each side of the fuselage pod. I found that the soft, plastic
fuselage easily cuts with a few strokes of a hobby knife. The
servos are connected to the control surfaces with flexible
pushrods. Hot glue holds the pushrod sleeves to the airframe.
For power, I used an ElectriFly Rimfire 250 outrunner
motor. I attached it directly to the existing plastic firewall using
three 2 x 3/8-inch screws. The Rimfire motor is nearly 2 ounces
lighter and more efficient than the can motor it replaces.
An ElectriFly 8-amp ESC, a GWS 6 x 3 propeller, and 3S
800mAh LiPo batteries from various manufacturers, round out
the power system.
My completed model weighs 11.3 ounces ready to fly— a
full 33% lighter than the advertised 16.9 ounces. After you
factor in the power increase from the brushless motor system
and the oversized control surfaces, the numbers indicate that
this tame trainer just got sportier.
Takeoffs happen in mere inches, and the Red Hawk will
easily sustain a vertical climbout. If you throttle back, the
airplane will slow to a crawl. I usually use half throttle or less.
This allows me to do waist-high Figure Eights with a touchand-
go between turnarounds. Loops are no problem, but
inverted flight is tricky.
What surprised me most about the Red Hawk was its
superb glide performance. My modernized Red Hawk is as
much fun as I’ve ever had without ailerons.
Red Hawk Kitbash #2—Seeing Double
After I had proven the soundness of the Red Hawk’s basic
design with my first project, I decided to get more exotic. My
second Red Hawk iteration is a twin created by joining two
fuselages and an extended wing. I thought this version strayed
too far to keep its Red Hawk moniker, so I renamed it JATH
(Joined at the Hip).
To create an enlarged wing, I split
one wing in half and spliced in the
center section of another wing. This
increased the span by 14 inches and
placed the wing joints at the fuselage
saddles (where they wouldn’t be prone
to twisting). I removed the individual
carbon-fi ber spars from each wing
section and glued in a single spar that
spanned all three panels.
To rigidly join the two fuselages, I
utilized two sections of arrow shaft. I
drilled holes slightly smaller than the
outer diameter of the shaft in each
fuselage. I then pushed the shafts into
the holes with a twisting motion. I
added Goop adhesive to every shaft/
fuselage joint that I could reach. The
resulting structure is surprisingly rigid.
For control, I used an inverted
V-tail arrangement. A Hitec HS-55
micro servo in each fuselage pod
actuates its respective half of the
V-tail. Initially, I built the V-tail using
the leftover wingtip sections from the
wing modifi cation. I liked the surface’s
curved look and built-in red fi nish.
However, I later discarded these parts
for reasons I’ll divulge later.
To prove that brushed motors
are still a valid option, I used 6-volt
Speed-400 engines with Gunther
push-on propellers. Anyone who fl ew
electrics at the turn of the century
should be feeling a twinge of nostalgia
at the mention of this combination.
Each motor has its own E-fl ite 20-amp
ESC and 2S 1300 mAh LiPo battery.
I placed the Futaba R617FS receiver
in the right fuselage. The forward
arrow shaft doubles as a conduit for the
wires, from the port servo and ESC to
the receiver.
To provide some measure of ground
handling, I set up a differential-throttle
mix on my Futaba 7C transmitter. This
allows me to individually control each
motor with rudder inputs. Although not
as precise as a steerable tailwheel, it is
simple and works well.
The twin’s fi rst fl ight was made before
the landing gear was installed. As soon
as the airplane was launched, it showed
signs of lateral instability. The most
prominent indication was a signifi cant
Dutch Roll (unintentional yawing and
wing rocking).
The airplane was sensitive in pitch.
After nursing it around in the sky for
a few minutes, I brought JATH down
without damage.
Back in the shop, I added 1.5 ounces
of lead to the noses and installed
landing gear. These
changes moved the
CG forward, which I
believed would cure
the pitch sensitivity.
I was optimistic that
the Dutch Roll would
also disappear. On the
second fl ight, the pitch
problems were gone,
but the Dutch Roll
persisted.
Through no fault of
the airplane, I ended the second fl ight
with an unintentional spiral to the
ground. The damage was superfi cial and
easily repaired.
On my next trip back to the shop, I
replaced the original V-tail parts with
lighter Cellfoam 88 duplicates and
added separate vertical stabilizers (does
that make it a W-tail?). This moved the
CG farther forward, while (presumably)
improving lateral stability.
JATH’s third fl ight showed that the
vertical stabilizers cured the Dutch Roll
and made the airplane more pleasant
to fl y. It looks cool in the air and it’s
satisfying to see the direct cause-andeffect
of simple changes, such as the
addition of the vertical area.
Red Hawk Kitbash #3—
Uncharted Ground
For my third Red Hawk-themed
project, I wanted to do something I’ve
never attempted and that I didn’t fully
understand: asymmetry.
There are few full-scale asymmetric
aircraft to analyze. However, the two
prime examples of asymmetry, the
Blohm und Voss Bv 141 and the Rutan
Model 202 Boomerang, have good
handling qualities. There must be some
engineering logic behind these abstractlooking
aircraft.
I was unable to fi nd any useful
information about asymmetric design
philosophies in my model design
books, online, or even my Stability and
Control textbooks. I resorted to studying
three-view drawings of the Bv 141 and
Boomerang.
As I poured over the drawings, they
revealed a few secrets that made these
aircraft seem less radical than before.
I didn’t grasp every aspect of their
asymmetry, but I became confi dent
enough to believe that I could create
a fl yable asymmetric model using Red
Hawk parts.
The name for my model was obvious:
Miss Aligned. Other than its pusher
motor, Miss Aligned resembled the
layout of the Bv 141 in many ways.
Like JATH, the pods are joined with
arrow shafts. Rather than having two
identical cockpit-like pods out front,
I reworked the left pod to include a
Gatling gun and a huge cannon.
My goal was to get the airplane’s
lateral balance slightly right of the left
pod. This makes the position of the
single motor (mounted in the left pod)
have the same torque-canceling effect as
the right thrust that is incorporated into
many conventional airplanes.
The power system is the same as that
which I used on Kitbash #1. All of the
components, except the battery, were
placed in the left pod. The battery is
in the right pod with a wire extension
running through the forward arrow
shaft.
I underestimated
the balancing effect
of having the battery
in the right pod.
To shift the lateral
balance closer to the
left pod, I added .4
ounces of lead to
the left wingtip. This
placed the lateral
balance point 5/8 inch to the right of the
left pod, which, by no coincidence, is the
same location as the midpoints of the
wing and landing gear.
I was mostly sure that Miss Aligned
would fl y, but I was prepared to deal
with unexpected idiosyncrasies. I was
amazed when I began the fi rst takeoff
roll and needed no rudder input to keep
it on a straight path. The airplane lifted
off quickly and behaved normally.
The throttle/yaw coupling that I
expected never materialized. Neither
did the pitch/roll coupling I anticipated
from the off-center elevator. In short,
Miss Aligned’s predictability in fl ight
belies its quirky appearance.
What’s Next
I now have three practical airplanes
to enjoy. Kitbash #1 has joined my fleet
of utilitarian, stress-free, fly-anytime
airplanes. I like the way JATH flies, so I
plan to hang onto it and maybe install
brushless motors. Miss Aligned is a
gateway. My success with this project
has demystified asymmetric aircraft
for me and encouraged me to begin
planning a larger, more refined model
from the ground up.
If you’ll recall, my original point was
to illustrate how kitbashing off-theshelf
airframe components can both
expedite and inspire unique projects. My
combined shop time for all three of the
kitbash projects was roughly 10 hours—
much less time than it would have taken
me to scratch-build one model.
I explored these ideas with minimal
time and monetary investments. Projects
requiring too much of either resource
tend to dampen my audacity.
The next time modeling inspiration
strikes you in the middle of the night,
don’t go back to sleep. Find some
premade components and make that
aeronautical dream a reality.
Edition: Model Aviation - 2012/08
Page Numbers: 30,31,32,33,34
I enjoy making unique—and often unusual—airplanes.
Occasionally roaming away from the herd sustains my
interest in this hobby. Often, a project will evolve in my
head as a generic concept, rather than a well-defined end
product.
I may wake up in the middle of the night with the sudden
urge to build a trimotor airplane, perhaps an autogyro, or
maybe even a three-engine autogyro. To give my visions a
jump start and ensure that they are built, I attempt to find
off-the-shelf components to use—aka kitbashing. Whether it’s
the fuselage from a model I pranged three years ago, or a spare
wing from the clearance bin at the hobby shop, it’s all fair
game if I think it will expedite the project.
Sometimes, a good deal on airframe parts encourages me to
stock up for future projects. Having those parts and thinking,
“what if?” becomes the catalyst for a new endeavor.
I recently discovered a good deal on airframe parts for the
Flyzone Red Hawk, a discontinued beginner’s airplane. In stock
form, the Red Hawk uses a 380-size brushed motor, Ni-Cd
batteries, and a simplified V-tail control arrangement.
From a kitbashing standpoint, this left me with plenty of
latitude for alternate power systems and control methods.
A flood of ideas with varying levels of practicality and sanity
began pouring from my brain, so I purchased an armful of
wings and fuselages with which to tinker.
Red Hawk Kitbash #1—The Modernization
Because I had never flown a stock Red Hawk, I wanted my
first project to provide a baseline of the airplane’s performance
envelope. This knowledge would help me determine how
and when to use Red Hawk parts for subsequent projects.
Although my Red Hawk would cast a virtually identical
shadow as a stock version, I decided to equip it with a modern
power system and high-quality radio gear.
The pod-and-boom fuselage comes with an integrated
mount for V-tail control surfaces. I didn’t have any of the stock V-tail parts, so I cut new ones from 5mm Midwest Products
Cellfoam 88 sheet foam, allowing me to make the control
surfaces as large as I wanted. I used a low-temperature glue
gun to secure the surfaces to the mount.
To actuate the V-tail, I installed a Futaba S3114 microservo
on each side of the fuselage pod. I found that the soft, plastic
fuselage easily cuts with a few strokes of a hobby knife. The
servos are connected to the control surfaces with flexible
pushrods. Hot glue holds the pushrod sleeves to the airframe.
For power, I used an ElectriFly Rimfire 250 outrunner
motor. I attached it directly to the existing plastic firewall using
three 2 x 3/8-inch screws. The Rimfire motor is nearly 2 ounces
lighter and more efficient than the can motor it replaces.
An ElectriFly 8-amp ESC, a GWS 6 x 3 propeller, and 3S
800mAh LiPo batteries from various manufacturers, round out
the power system.
My completed model weighs 11.3 ounces ready to fly— a
full 33% lighter than the advertised 16.9 ounces. After you
factor in the power increase from the brushless motor system
and the oversized control surfaces, the numbers indicate that
this tame trainer just got sportier.
Takeoffs happen in mere inches, and the Red Hawk will
easily sustain a vertical climbout. If you throttle back, the
airplane will slow to a crawl. I usually use half throttle or less.
This allows me to do waist-high Figure Eights with a touchand-
go between turnarounds. Loops are no problem, but
inverted flight is tricky.
What surprised me most about the Red Hawk was its
superb glide performance. My modernized Red Hawk is as
much fun as I’ve ever had without ailerons.
Red Hawk Kitbash #2—Seeing Double
After I had proven the soundness of the Red Hawk’s basic
design with my first project, I decided to get more exotic. My
second Red Hawk iteration is a twin created by joining two
fuselages and an extended wing. I thought this version strayed
too far to keep its Red Hawk moniker, so I renamed it JATH
(Joined at the Hip).
To create an enlarged wing, I split
one wing in half and spliced in the
center section of another wing. This
increased the span by 14 inches and
placed the wing joints at the fuselage
saddles (where they wouldn’t be prone
to twisting). I removed the individual
carbon-fi ber spars from each wing
section and glued in a single spar that
spanned all three panels.
To rigidly join the two fuselages, I
utilized two sections of arrow shaft. I
drilled holes slightly smaller than the
outer diameter of the shaft in each
fuselage. I then pushed the shafts into
the holes with a twisting motion. I
added Goop adhesive to every shaft/
fuselage joint that I could reach. The
resulting structure is surprisingly rigid.
For control, I used an inverted
V-tail arrangement. A Hitec HS-55
micro servo in each fuselage pod
actuates its respective half of the
V-tail. Initially, I built the V-tail using
the leftover wingtip sections from the
wing modifi cation. I liked the surface’s
curved look and built-in red fi nish.
However, I later discarded these parts
for reasons I’ll divulge later.
To prove that brushed motors
are still a valid option, I used 6-volt
Speed-400 engines with Gunther
push-on propellers. Anyone who fl ew
electrics at the turn of the century
should be feeling a twinge of nostalgia
at the mention of this combination.
Each motor has its own E-fl ite 20-amp
ESC and 2S 1300 mAh LiPo battery.
I placed the Futaba R617FS receiver
in the right fuselage. The forward
arrow shaft doubles as a conduit for the
wires, from the port servo and ESC to
the receiver.
To provide some measure of ground
handling, I set up a differential-throttle
mix on my Futaba 7C transmitter. This
allows me to individually control each
motor with rudder inputs. Although not
as precise as a steerable tailwheel, it is
simple and works well.
The twin’s fi rst fl ight was made before
the landing gear was installed. As soon
as the airplane was launched, it showed
signs of lateral instability. The most
prominent indication was a signifi cant
Dutch Roll (unintentional yawing and
wing rocking).
The airplane was sensitive in pitch.
After nursing it around in the sky for
a few minutes, I brought JATH down
without damage.
Back in the shop, I added 1.5 ounces
of lead to the noses and installed
landing gear. These
changes moved the
CG forward, which I
believed would cure
the pitch sensitivity.
I was optimistic that
the Dutch Roll would
also disappear. On the
second fl ight, the pitch
problems were gone,
but the Dutch Roll
persisted.
Through no fault of
the airplane, I ended the second fl ight
with an unintentional spiral to the
ground. The damage was superfi cial and
easily repaired.
On my next trip back to the shop, I
replaced the original V-tail parts with
lighter Cellfoam 88 duplicates and
added separate vertical stabilizers (does
that make it a W-tail?). This moved the
CG farther forward, while (presumably)
improving lateral stability.
JATH’s third fl ight showed that the
vertical stabilizers cured the Dutch Roll
and made the airplane more pleasant
to fl y. It looks cool in the air and it’s
satisfying to see the direct cause-andeffect
of simple changes, such as the
addition of the vertical area.
Red Hawk Kitbash #3—
Uncharted Ground
For my third Red Hawk-themed
project, I wanted to do something I’ve
never attempted and that I didn’t fully
understand: asymmetry.
There are few full-scale asymmetric
aircraft to analyze. However, the two
prime examples of asymmetry, the
Blohm und Voss Bv 141 and the Rutan
Model 202 Boomerang, have good
handling qualities. There must be some
engineering logic behind these abstractlooking
aircraft.
I was unable to fi nd any useful
information about asymmetric design
philosophies in my model design
books, online, or even my Stability and
Control textbooks. I resorted to studying
three-view drawings of the Bv 141 and
Boomerang.
As I poured over the drawings, they
revealed a few secrets that made these
aircraft seem less radical than before.
I didn’t grasp every aspect of their
asymmetry, but I became confi dent
enough to believe that I could create
a fl yable asymmetric model using Red
Hawk parts.
The name for my model was obvious:
Miss Aligned. Other than its pusher
motor, Miss Aligned resembled the
layout of the Bv 141 in many ways.
Like JATH, the pods are joined with
arrow shafts. Rather than having two
identical cockpit-like pods out front,
I reworked the left pod to include a
Gatling gun and a huge cannon.
My goal was to get the airplane’s
lateral balance slightly right of the left
pod. This makes the position of the
single motor (mounted in the left pod)
have the same torque-canceling effect as
the right thrust that is incorporated into
many conventional airplanes.
The power system is the same as that
which I used on Kitbash #1. All of the
components, except the battery, were
placed in the left pod. The battery is
in the right pod with a wire extension
running through the forward arrow
shaft.
I underestimated
the balancing effect
of having the battery
in the right pod.
To shift the lateral
balance closer to the
left pod, I added .4
ounces of lead to
the left wingtip. This
placed the lateral
balance point 5/8 inch to the right of the
left pod, which, by no coincidence, is the
same location as the midpoints of the
wing and landing gear.
I was mostly sure that Miss Aligned
would fl y, but I was prepared to deal
with unexpected idiosyncrasies. I was
amazed when I began the fi rst takeoff
roll and needed no rudder input to keep
it on a straight path. The airplane lifted
off quickly and behaved normally.
The throttle/yaw coupling that I
expected never materialized. Neither
did the pitch/roll coupling I anticipated
from the off-center elevator. In short,
Miss Aligned’s predictability in fl ight
belies its quirky appearance.
What’s Next
I now have three practical airplanes
to enjoy. Kitbash #1 has joined my fleet
of utilitarian, stress-free, fly-anytime
airplanes. I like the way JATH flies, so I
plan to hang onto it and maybe install
brushless motors. Miss Aligned is a
gateway. My success with this project
has demystified asymmetric aircraft
for me and encouraged me to begin
planning a larger, more refined model
from the ground up.
If you’ll recall, my original point was
to illustrate how kitbashing off-theshelf
airframe components can both
expedite and inspire unique projects. My
combined shop time for all three of the
kitbash projects was roughly 10 hours—
much less time than it would have taken
me to scratch-build one model.
I explored these ideas with minimal
time and monetary investments. Projects
requiring too much of either resource
tend to dampen my audacity.
The next time modeling inspiration
strikes you in the middle of the night,
don’t go back to sleep. Find some
premade components and make that
aeronautical dream a reality.
Edition: Model Aviation - 2012/08
Page Numbers: 30,31,32,33,34
I enjoy making unique—and often unusual—airplanes.
Occasionally roaming away from the herd sustains my
interest in this hobby. Often, a project will evolve in my
head as a generic concept, rather than a well-defined end
product.
I may wake up in the middle of the night with the sudden
urge to build a trimotor airplane, perhaps an autogyro, or
maybe even a three-engine autogyro. To give my visions a
jump start and ensure that they are built, I attempt to find
off-the-shelf components to use—aka kitbashing. Whether it’s
the fuselage from a model I pranged three years ago, or a spare
wing from the clearance bin at the hobby shop, it’s all fair
game if I think it will expedite the project.
Sometimes, a good deal on airframe parts encourages me to
stock up for future projects. Having those parts and thinking,
“what if?” becomes the catalyst for a new endeavor.
I recently discovered a good deal on airframe parts for the
Flyzone Red Hawk, a discontinued beginner’s airplane. In stock
form, the Red Hawk uses a 380-size brushed motor, Ni-Cd
batteries, and a simplified V-tail control arrangement.
From a kitbashing standpoint, this left me with plenty of
latitude for alternate power systems and control methods.
A flood of ideas with varying levels of practicality and sanity
began pouring from my brain, so I purchased an armful of
wings and fuselages with which to tinker.
Red Hawk Kitbash #1—The Modernization
Because I had never flown a stock Red Hawk, I wanted my
first project to provide a baseline of the airplane’s performance
envelope. This knowledge would help me determine how
and when to use Red Hawk parts for subsequent projects.
Although my Red Hawk would cast a virtually identical
shadow as a stock version, I decided to equip it with a modern
power system and high-quality radio gear.
The pod-and-boom fuselage comes with an integrated
mount for V-tail control surfaces. I didn’t have any of the stock V-tail parts, so I cut new ones from 5mm Midwest Products
Cellfoam 88 sheet foam, allowing me to make the control
surfaces as large as I wanted. I used a low-temperature glue
gun to secure the surfaces to the mount.
To actuate the V-tail, I installed a Futaba S3114 microservo
on each side of the fuselage pod. I found that the soft, plastic
fuselage easily cuts with a few strokes of a hobby knife. The
servos are connected to the control surfaces with flexible
pushrods. Hot glue holds the pushrod sleeves to the airframe.
For power, I used an ElectriFly Rimfire 250 outrunner
motor. I attached it directly to the existing plastic firewall using
three 2 x 3/8-inch screws. The Rimfire motor is nearly 2 ounces
lighter and more efficient than the can motor it replaces.
An ElectriFly 8-amp ESC, a GWS 6 x 3 propeller, and 3S
800mAh LiPo batteries from various manufacturers, round out
the power system.
My completed model weighs 11.3 ounces ready to fly— a
full 33% lighter than the advertised 16.9 ounces. After you
factor in the power increase from the brushless motor system
and the oversized control surfaces, the numbers indicate that
this tame trainer just got sportier.
Takeoffs happen in mere inches, and the Red Hawk will
easily sustain a vertical climbout. If you throttle back, the
airplane will slow to a crawl. I usually use half throttle or less.
This allows me to do waist-high Figure Eights with a touchand-
go between turnarounds. Loops are no problem, but
inverted flight is tricky.
What surprised me most about the Red Hawk was its
superb glide performance. My modernized Red Hawk is as
much fun as I’ve ever had without ailerons.
Red Hawk Kitbash #2—Seeing Double
After I had proven the soundness of the Red Hawk’s basic
design with my first project, I decided to get more exotic. My
second Red Hawk iteration is a twin created by joining two
fuselages and an extended wing. I thought this version strayed
too far to keep its Red Hawk moniker, so I renamed it JATH
(Joined at the Hip).
To create an enlarged wing, I split
one wing in half and spliced in the
center section of another wing. This
increased the span by 14 inches and
placed the wing joints at the fuselage
saddles (where they wouldn’t be prone
to twisting). I removed the individual
carbon-fi ber spars from each wing
section and glued in a single spar that
spanned all three panels.
To rigidly join the two fuselages, I
utilized two sections of arrow shaft. I
drilled holes slightly smaller than the
outer diameter of the shaft in each
fuselage. I then pushed the shafts into
the holes with a twisting motion. I
added Goop adhesive to every shaft/
fuselage joint that I could reach. The
resulting structure is surprisingly rigid.
For control, I used an inverted
V-tail arrangement. A Hitec HS-55
micro servo in each fuselage pod
actuates its respective half of the
V-tail. Initially, I built the V-tail using
the leftover wingtip sections from the
wing modifi cation. I liked the surface’s
curved look and built-in red fi nish.
However, I later discarded these parts
for reasons I’ll divulge later.
To prove that brushed motors
are still a valid option, I used 6-volt
Speed-400 engines with Gunther
push-on propellers. Anyone who fl ew
electrics at the turn of the century
should be feeling a twinge of nostalgia
at the mention of this combination.
Each motor has its own E-fl ite 20-amp
ESC and 2S 1300 mAh LiPo battery.
I placed the Futaba R617FS receiver
in the right fuselage. The forward
arrow shaft doubles as a conduit for the
wires, from the port servo and ESC to
the receiver.
To provide some measure of ground
handling, I set up a differential-throttle
mix on my Futaba 7C transmitter. This
allows me to individually control each
motor with rudder inputs. Although not
as precise as a steerable tailwheel, it is
simple and works well.
The twin’s fi rst fl ight was made before
the landing gear was installed. As soon
as the airplane was launched, it showed
signs of lateral instability. The most
prominent indication was a signifi cant
Dutch Roll (unintentional yawing and
wing rocking).
The airplane was sensitive in pitch.
After nursing it around in the sky for
a few minutes, I brought JATH down
without damage.
Back in the shop, I added 1.5 ounces
of lead to the noses and installed
landing gear. These
changes moved the
CG forward, which I
believed would cure
the pitch sensitivity.
I was optimistic that
the Dutch Roll would
also disappear. On the
second fl ight, the pitch
problems were gone,
but the Dutch Roll
persisted.
Through no fault of
the airplane, I ended the second fl ight
with an unintentional spiral to the
ground. The damage was superfi cial and
easily repaired.
On my next trip back to the shop, I
replaced the original V-tail parts with
lighter Cellfoam 88 duplicates and
added separate vertical stabilizers (does
that make it a W-tail?). This moved the
CG farther forward, while (presumably)
improving lateral stability.
JATH’s third fl ight showed that the
vertical stabilizers cured the Dutch Roll
and made the airplane more pleasant
to fl y. It looks cool in the air and it’s
satisfying to see the direct cause-andeffect
of simple changes, such as the
addition of the vertical area.
Red Hawk Kitbash #3—
Uncharted Ground
For my third Red Hawk-themed
project, I wanted to do something I’ve
never attempted and that I didn’t fully
understand: asymmetry.
There are few full-scale asymmetric
aircraft to analyze. However, the two
prime examples of asymmetry, the
Blohm und Voss Bv 141 and the Rutan
Model 202 Boomerang, have good
handling qualities. There must be some
engineering logic behind these abstractlooking
aircraft.
I was unable to fi nd any useful
information about asymmetric design
philosophies in my model design
books, online, or even my Stability and
Control textbooks. I resorted to studying
three-view drawings of the Bv 141 and
Boomerang.
As I poured over the drawings, they
revealed a few secrets that made these
aircraft seem less radical than before.
I didn’t grasp every aspect of their
asymmetry, but I became confi dent
enough to believe that I could create
a fl yable asymmetric model using Red
Hawk parts.
The name for my model was obvious:
Miss Aligned. Other than its pusher
motor, Miss Aligned resembled the
layout of the Bv 141 in many ways.
Like JATH, the pods are joined with
arrow shafts. Rather than having two
identical cockpit-like pods out front,
I reworked the left pod to include a
Gatling gun and a huge cannon.
My goal was to get the airplane’s
lateral balance slightly right of the left
pod. This makes the position of the
single motor (mounted in the left pod)
have the same torque-canceling effect as
the right thrust that is incorporated into
many conventional airplanes.
The power system is the same as that
which I used on Kitbash #1. All of the
components, except the battery, were
placed in the left pod. The battery is
in the right pod with a wire extension
running through the forward arrow
shaft.
I underestimated
the balancing effect
of having the battery
in the right pod.
To shift the lateral
balance closer to the
left pod, I added .4
ounces of lead to
the left wingtip. This
placed the lateral
balance point 5/8 inch to the right of the
left pod, which, by no coincidence, is the
same location as the midpoints of the
wing and landing gear.
I was mostly sure that Miss Aligned
would fl y, but I was prepared to deal
with unexpected idiosyncrasies. I was
amazed when I began the fi rst takeoff
roll and needed no rudder input to keep
it on a straight path. The airplane lifted
off quickly and behaved normally.
The throttle/yaw coupling that I
expected never materialized. Neither
did the pitch/roll coupling I anticipated
from the off-center elevator. In short,
Miss Aligned’s predictability in fl ight
belies its quirky appearance.
What’s Next
I now have three practical airplanes
to enjoy. Kitbash #1 has joined my fleet
of utilitarian, stress-free, fly-anytime
airplanes. I like the way JATH flies, so I
plan to hang onto it and maybe install
brushless motors. Miss Aligned is a
gateway. My success with this project
has demystified asymmetric aircraft
for me and encouraged me to begin
planning a larger, more refined model
from the ground up.
If you’ll recall, my original point was
to illustrate how kitbashing off-theshelf
airframe components can both
expedite and inspire unique projects. My
combined shop time for all three of the
kitbash projects was roughly 10 hours—
much less time than it would have taken
me to scratch-build one model.
I explored these ideas with minimal
time and monetary investments. Projects
requiring too much of either resource
tend to dampen my audacity.
The next time modeling inspiration
strikes you in the middle of the night,
don’t go back to sleep. Find some
premade components and make that
aeronautical dream a reality.