142 MODEL AVIATION
CONTROL LINE SCALE
Bill Boss, 77-06 269th St., New Hyde Park NY 11040
IT HAS BEEN quite some time since I
covered some of the basics associated with
building our Scale models. I know that what
I will write about may be old news to many
of our advanced CL modelers (Scale or
otherwise), but there is always a new group
of modelers coming along, and some of
what I write here may be beneficial to them.
This month I’m going to review the
many ways in which CL-model leadouts can
be installed. The accompanying sketch
shows the various ways in which the
leadouts may be mounted or anchored in/to
our models.
You might ask why there is so much
concern about how the leadouts are installed.
What is the purpose of the leadouts? Do they
have to be installed in any particular manner
to keep the model stable in flight? What
types of supports are used to hold the
leadouts in place? What effect does the
leadout and bellcrank placement have on the
scale interior of the model? And what are
the rules regarding the use of removable
leadout guides on our Scale models?
The answer to the first question is that
the leadouts provide a means by which we
attach the flying lines to the model’s
bellcrank. The placement of the bellcrank
and leadouts will depend on the type of
airplane you are building: biplane, highwing,
low-wing, or midwing configuration.
When installing the leadouts and
bellcrank, we make every effort to create a
straight line from the control handle through
the lines to the bellcrank. This depends on
the bellcrank being mounted at, or near, the
Bellcrank installation (L) and removable leadout guide (R) in Mike Welshans’ Rearwin Speedster. Welshans photos.
This month’s column explores various leadout and guide placements for CL Scale
models. The text contains details on each type. Sketch by the author.
07sig5.QXD 4/23/04 10:07 am Page 142
model’s vertical CG. The straight-line path
provides the best chance of having a
smooth-operating control system that will
provide a level and stable flight attitude.
To achieve a good flight attitude and
control, the leadouts must be supported in
some manner near the tip of the inboard
wing. If the leadouts are not supported at
the inboard wingtip, the model will most
likely fly in an erratic manner, and we will
end up with some disastrous consequences.
The sketch shows several of the most
common methods of installing the leadouts.
The first two illustrations show how we
might support the leadouts in biplane and
high-wing models, both of which present
problems because there is no easy way to
hide the leadouts to provide clean-looking
models for competition and static judging.
In the biplane, the leadouts are
generally supported by placing a plywood
or sheet-metal piece attached to the struts
between the upper and lower wing. The
support is best located at a point on the
struts that is approximately one-third to
one-half the distance between the upper
and lower wing when measured from the
upper surface of the bottom wing.
In the high-wing model, the leadouts are
generally supported by a device shaped
from piano wire that is secured to a rib near
the wing’s inboard tip. The length of the
support is governed by where the bellcrank
is mounted in the model’s fuselage.
Remember that you want to maintain a
straight line from handle to bellcrank and
for the leadouts to remain parallel to the
lower surface of the model’s wing.
The “Low Wing-A” and “Mid-Wing”
sketches show how the leadouts and
leadout guide might be installed on those
models. Again, the location of the bellcrank
and general use of the model might dictate
the manner in which the leadouts and guide
are installed.
The low-wing and midwing sketches
July 2004 143
All engines feature front and rear NOVAROSSI patented displaced ball bearings.
Engines are ABC design and use special alloy aluminum piston running in a hard chromed
brass alloy sleeve. Manufactured in Italy. Specifications supplied by manufacturer.
NOVAROSSI aircraft engines are distributed in the US by PlanetHobby.com, Inc.
Pipes • Manifolds • Glow Plugs • Parts • Accessories in Stock 7477 Wood Rail Cove • Memphis,TN 38119
RX21FR .21 Turbo Speed Engine.
3 exhaust & 7 intake ports. 2.2 hp at 34,300
rpm.Wt. 11.6oz. R/C or Venturi.Turbo plug.
List $500.
RX21F/N .21 Turbo Speed Engine.
1 exhaust & 4 intake ports. 2.2 hp at 34,300
rpm. Wt. 11.6oz. R/C or Venturi. Turbo plug.
Lower timed for operations without a tuned
pipe. List $400. (not shown)
C61F .60 Aircraft Engine.
1 exhaust & 3 intake ports 2.45
hp at 17,000 rpm.Wt. 22.3oz.
R/C carb with in-flight mixture
control. List $475.
FX15TC .15 Turbo Aircraft Engine
1 exhaust & 8 intake ports. 1.3hp at 34,000
rpm.Wt. 9.2oz. R/C carb or Venturi.Turbo
plug. List $300.
FX15C .15 Aircraft Engine.
1 exhaust & 3 intake ports 1.2 hp at
33,000 rpm.Wt 9.2oz. R/C carb or
Venturi. List $350.
PlanetHobby.com, Inc.
(901) 755-1536
Catalogs Upon Request • Dealer Program
Muffled and Tuned Pipes
Turbo Glow
Plug
Turbo Crank
Optional Exhaust
Manifolds
Advanced Porting
and Piston Design
sale $159
sale $229
sale $219
sale $199
NOVAROSSI Rear Exhaust Engines
email:
SUMMER SALE!
Order on our secure website:
www.planethobby.com
[email protected]
Sale ENDS Sept. 20, 2004
NOVAROSSI
Performance Innovations
sale $189
07sig5.QXD 4/23/04 10:08 am Page 143
show the guide as a fixed plywood piece
installed at a point close to the model’s
inboard wingtip. If the model will be used
for general fun-flying and its aesthetics is
not a factor, the “Low Wing-A” installation
might be acceptable.
However, if the aircraft is to be used for
competition, the “Mid-Wing” installation
might be in order. In this case, the bellcrank
can be installed low in the fuselage, and
only a small portion of the leadouts would
be visible under the wing.
Also shown in the drawing is the option
of a removable leadout guide. This could be
used in place of the fixed type shown. You
could make a removable guide from sheet
aluminum, brass, or copper, and it would
144 MODEL AVIATION
require that you install a piece of metal or
nuts at an appropriate rib location into which
you could thread small screws to hold the
removable guide in place.
A good example of a removable leadout
guide used on a high-wing model is in Mike
Welshans’ Rearwin Speedster. He entered it
in the 2003 Nats, and I featured the model in
the January 2004 column.
One of this month’s photos shows the
three-line bellcrank mounted in the bottom
of the Speedster’s fuselage. The other photo
shows the removable leadout guide made
long enough to keep that straight-line path
of the control system I mentioned earlier
while maintaining the leadouts parallel with
the bottom of the upper wing. Although it
might be obvious to many, using a
removable guide requires the use of stranded
wire leadouts.
It would seem that with a little ingenuity
and planning, you could improve almost any
CL Scale competition model’s appearance
by using stranded wire leadouts and
removable guides. Most World War II
fighters and bombers certainly lend
themselves to this idea; there are areas on
the airplanes’ wings and fuselages in which
removable panels might be made for storing
coiled leadouts until ready for flight.
You could also apply that idea to the
biplane and high-wing types, in which a
finely executed removable fuselage panel
could be used to store the leadouts. The
object of all this is to provide the cleanestlooking
model for static judging.
You can find rules on using removable
leadout guides in AMA’s Competition
Regulations. For CL Precision Scale, the
“Unified Scale Judging Regulations” (Page
153, paragraph 6, item f) state that leadout
guides may be removed for static judging
and reinstalled before flight.
In the Sport Scale event, permission to
use removable leadout guides is covered
under “Static Judging” (page 160, paragraph
5.5, item e). Since the CL Designer and
Profile Scale rules are based on the Sport
Scale rules, using removable leadout guides
is also permissible in those events.
The last of the small drawings is “Low
Wing-B.” In this type of installation, the
master
airscrew
Windsor Propeller Co.
P.O. Box 250, Rancho Cordova,
CA 95741-0250
ph. 916.631.8385
email. [email protected]
The K Series
has been
redeisgned
with:
•Slightly
rounded tips
•Thinner
blades with a
bit more blade
area.
•Noticeable
performance
improvement
for both 2 and
4-stroke engines.
•Lower pitches
for aerobatic
and hovering
maneuvers.
Sizes
12x4, 12x5, $ 3.19
12x6, 12x8 $ 3.19
13x5, 13x6, $ 4.29
13x8 $ 4.29
14x6, 14x8 $ 5.99
15x6, 15x8 $ 7.59
16x8, 16x8 $ 8.29
New
K Series
Planned Giving to AMA
You may make gifts to AMA of:
or with a Charitable Remainder Trust (CRT)
• Immediate income tax deduction
• Lifetime income for you and your spouse (or other
beneficiary)
• Reduction in estate taxes
• Money for your favorite charities
Interested? Contact AMA Executive Director Joyce Hager at
(765) 287-1256, extension 200.
Cash
Securities
Insurance
Gems
Real Estate
Etc.
07sig5.QXD 4/23/04 10:08 am Page 144
July 2004 145
Micro-Mark has more than 2,600 name-brand and
hard-to-find tools and accessories…many at discount
prices. You’ll complete your projects in less time
with more professional results!
340-3274 Snyder Avenue
Berkeley Heights, NJ 07922-1538
NAME
ADDRESS
CITY
STATE ZIP
To order our catalog, send $1 and this coupon to:
1-800-225-1066 • www.micromark.com
®
Please say you saw our ad in the July issue of Model Aviation.
MICRO-MARK’S
got it !
#83099
“STAND-IN” HOLDER FOR LARGE SCALE MODELS
OVER A DOZEN MODELS OF WWI, WWII, AND CLASSIC CIVILIAN
AIRCRAFT AVAILABLE WITH MORE VERSIONS TO FOLLOW!
• Electric motor(s) with prop and gear reduction included.
• Highly prefabricated for very short building times.
• 3-4 functions: rudder, aileron & elevator (rudder & ailerons on
one servo, or on separate servos.)
• Laser-cut wood parts for an accurate fit.
• Propeller and spinner included.
• Landing gear and wheels included.
(some kits have removable gear for grass field flying.)
• Contact your local hobby shop, or order direct at: www.djaerotech.com
Ryan ST / PT-16
Wingspan: 28.1 in. • Length: 20.2 in.
Weight: 4.5-5.5 oz. (ready to fly)
Wing Loading: 5.5-6.7 oz/sq. ft.
We
carry
E-tec Li-Poly
batteries &
chargers
Single motor WWII kits ....$48.95
Lockheed P-38...............$56.95
Curtiss Jenny .................$64.95
Sopwith Camel...............$72.95
Fokker Triplane ..............$73.95
DC-3 ............................$66.95
Lockheed Electra............$68.95
Piper J-3 Cub.................$51.95
Curtiss-Wright Junior.......$51.95
Ryan ST / PT-16.............$59.95
B-17F .........................$124.95
(Shipping & Handling extra)
Prices subject to
change without notice.
Visit the AMA Education Committee
Web site at www.buildandfly.com.
bellcrank leadouts are installed wholly
within the wing structure. This installation is
most desirable because it provides the
cleanest appearance of all the types and
allows the builder to incorporate full cockpit
details if so desired.
Although I have discussed keeping that
straight-line path of the control system,
many modelers’ experiences have shown
that the small amount of dihedral in most
“Low Wing-B”-type airplanes has little or no
ill effect on this kind of model’s stability and
flying attitude. I suppose the only drawback
would be the limited access you would have
to the bellcrank, etc. for adjustments and
repair. Your control-system installation
would have to be extremely good before
completing the model.
In the coming months I’ll make an effort
to cover more of the things that might be
considered “basic.”
Contest Activity: The Garden State Circle
Burners (GSCB) will be holding its annual
CL Scale Meet September 12, 2004, at the
club field. Events will include Precision,
Sport, Profile, Team, and Fun Scale.
For full contest details, field location, and
special event rules, contact the GSCB in care
of Mary Knight, 51 Ringwood Ave.,
Pompton Lakes NJ 07442.
Please send ideas, notice of upcoming CL
Scale events, contest reports, and especially
photos of CL Scale activity to me at the
address at the top of this column. MA
07sig5.QXD 4/23/04 10:08 am Page 145
Edition: Model Aviation - 2004/07
Page Numbers: 142,143,144,145
Edition: Model Aviation - 2004/07
Page Numbers: 142,143,144,145
142 MODEL AVIATION
CONTROL LINE SCALE
Bill Boss, 77-06 269th St., New Hyde Park NY 11040
IT HAS BEEN quite some time since I
covered some of the basics associated with
building our Scale models. I know that what
I will write about may be old news to many
of our advanced CL modelers (Scale or
otherwise), but there is always a new group
of modelers coming along, and some of
what I write here may be beneficial to them.
This month I’m going to review the
many ways in which CL-model leadouts can
be installed. The accompanying sketch
shows the various ways in which the
leadouts may be mounted or anchored in/to
our models.
You might ask why there is so much
concern about how the leadouts are installed.
What is the purpose of the leadouts? Do they
have to be installed in any particular manner
to keep the model stable in flight? What
types of supports are used to hold the
leadouts in place? What effect does the
leadout and bellcrank placement have on the
scale interior of the model? And what are
the rules regarding the use of removable
leadout guides on our Scale models?
The answer to the first question is that
the leadouts provide a means by which we
attach the flying lines to the model’s
bellcrank. The placement of the bellcrank
and leadouts will depend on the type of
airplane you are building: biplane, highwing,
low-wing, or midwing configuration.
When installing the leadouts and
bellcrank, we make every effort to create a
straight line from the control handle through
the lines to the bellcrank. This depends on
the bellcrank being mounted at, or near, the
Bellcrank installation (L) and removable leadout guide (R) in Mike Welshans’ Rearwin Speedster. Welshans photos.
This month’s column explores various leadout and guide placements for CL Scale
models. The text contains details on each type. Sketch by the author.
07sig5.QXD 4/23/04 10:07 am Page 142
model’s vertical CG. The straight-line path
provides the best chance of having a
smooth-operating control system that will
provide a level and stable flight attitude.
To achieve a good flight attitude and
control, the leadouts must be supported in
some manner near the tip of the inboard
wing. If the leadouts are not supported at
the inboard wingtip, the model will most
likely fly in an erratic manner, and we will
end up with some disastrous consequences.
The sketch shows several of the most
common methods of installing the leadouts.
The first two illustrations show how we
might support the leadouts in biplane and
high-wing models, both of which present
problems because there is no easy way to
hide the leadouts to provide clean-looking
models for competition and static judging.
In the biplane, the leadouts are
generally supported by placing a plywood
or sheet-metal piece attached to the struts
between the upper and lower wing. The
support is best located at a point on the
struts that is approximately one-third to
one-half the distance between the upper
and lower wing when measured from the
upper surface of the bottom wing.
In the high-wing model, the leadouts are
generally supported by a device shaped
from piano wire that is secured to a rib near
the wing’s inboard tip. The length of the
support is governed by where the bellcrank
is mounted in the model’s fuselage.
Remember that you want to maintain a
straight line from handle to bellcrank and
for the leadouts to remain parallel to the
lower surface of the model’s wing.
The “Low Wing-A” and “Mid-Wing”
sketches show how the leadouts and
leadout guide might be installed on those
models. Again, the location of the bellcrank
and general use of the model might dictate
the manner in which the leadouts and guide
are installed.
The low-wing and midwing sketches
July 2004 143
All engines feature front and rear NOVAROSSI patented displaced ball bearings.
Engines are ABC design and use special alloy aluminum piston running in a hard chromed
brass alloy sleeve. Manufactured in Italy. Specifications supplied by manufacturer.
NOVAROSSI aircraft engines are distributed in the US by PlanetHobby.com, Inc.
Pipes • Manifolds • Glow Plugs • Parts • Accessories in Stock 7477 Wood Rail Cove • Memphis,TN 38119
RX21FR .21 Turbo Speed Engine.
3 exhaust & 7 intake ports. 2.2 hp at 34,300
rpm.Wt. 11.6oz. R/C or Venturi.Turbo plug.
List $500.
RX21F/N .21 Turbo Speed Engine.
1 exhaust & 4 intake ports. 2.2 hp at 34,300
rpm. Wt. 11.6oz. R/C or Venturi. Turbo plug.
Lower timed for operations without a tuned
pipe. List $400. (not shown)
C61F .60 Aircraft Engine.
1 exhaust & 3 intake ports 2.45
hp at 17,000 rpm.Wt. 22.3oz.
R/C carb with in-flight mixture
control. List $475.
FX15TC .15 Turbo Aircraft Engine
1 exhaust & 8 intake ports. 1.3hp at 34,000
rpm.Wt. 9.2oz. R/C carb or Venturi.Turbo
plug. List $300.
FX15C .15 Aircraft Engine.
1 exhaust & 3 intake ports 1.2 hp at
33,000 rpm.Wt 9.2oz. R/C carb or
Venturi. List $350.
PlanetHobby.com, Inc.
(901) 755-1536
Catalogs Upon Request • Dealer Program
Muffled and Tuned Pipes
Turbo Glow
Plug
Turbo Crank
Optional Exhaust
Manifolds
Advanced Porting
and Piston Design
sale $159
sale $229
sale $219
sale $199
NOVAROSSI Rear Exhaust Engines
email:
SUMMER SALE!
Order on our secure website:
www.planethobby.com
[email protected]
Sale ENDS Sept. 20, 2004
NOVAROSSI
Performance Innovations
sale $189
07sig5.QXD 4/23/04 10:08 am Page 143
show the guide as a fixed plywood piece
installed at a point close to the model’s
inboard wingtip. If the model will be used
for general fun-flying and its aesthetics is
not a factor, the “Low Wing-A” installation
might be acceptable.
However, if the aircraft is to be used for
competition, the “Mid-Wing” installation
might be in order. In this case, the bellcrank
can be installed low in the fuselage, and
only a small portion of the leadouts would
be visible under the wing.
Also shown in the drawing is the option
of a removable leadout guide. This could be
used in place of the fixed type shown. You
could make a removable guide from sheet
aluminum, brass, or copper, and it would
144 MODEL AVIATION
require that you install a piece of metal or
nuts at an appropriate rib location into which
you could thread small screws to hold the
removable guide in place.
A good example of a removable leadout
guide used on a high-wing model is in Mike
Welshans’ Rearwin Speedster. He entered it
in the 2003 Nats, and I featured the model in
the January 2004 column.
One of this month’s photos shows the
three-line bellcrank mounted in the bottom
of the Speedster’s fuselage. The other photo
shows the removable leadout guide made
long enough to keep that straight-line path
of the control system I mentioned earlier
while maintaining the leadouts parallel with
the bottom of the upper wing. Although it
might be obvious to many, using a
removable guide requires the use of stranded
wire leadouts.
It would seem that with a little ingenuity
and planning, you could improve almost any
CL Scale competition model’s appearance
by using stranded wire leadouts and
removable guides. Most World War II
fighters and bombers certainly lend
themselves to this idea; there are areas on
the airplanes’ wings and fuselages in which
removable panels might be made for storing
coiled leadouts until ready for flight.
You could also apply that idea to the
biplane and high-wing types, in which a
finely executed removable fuselage panel
could be used to store the leadouts. The
object of all this is to provide the cleanestlooking
model for static judging.
You can find rules on using removable
leadout guides in AMA’s Competition
Regulations. For CL Precision Scale, the
“Unified Scale Judging Regulations” (Page
153, paragraph 6, item f) state that leadout
guides may be removed for static judging
and reinstalled before flight.
In the Sport Scale event, permission to
use removable leadout guides is covered
under “Static Judging” (page 160, paragraph
5.5, item e). Since the CL Designer and
Profile Scale rules are based on the Sport
Scale rules, using removable leadout guides
is also permissible in those events.
The last of the small drawings is “Low
Wing-B.” In this type of installation, the
master
airscrew
Windsor Propeller Co.
P.O. Box 250, Rancho Cordova,
CA 95741-0250
ph. 916.631.8385
email. [email protected]
The K Series
has been
redeisgned
with:
•Slightly
rounded tips
•Thinner
blades with a
bit more blade
area.
•Noticeable
performance
improvement
for both 2 and
4-stroke engines.
•Lower pitches
for aerobatic
and hovering
maneuvers.
Sizes
12x4, 12x5, $ 3.19
12x6, 12x8 $ 3.19
13x5, 13x6, $ 4.29
13x8 $ 4.29
14x6, 14x8 $ 5.99
15x6, 15x8 $ 7.59
16x8, 16x8 $ 8.29
New
K Series
Planned Giving to AMA
You may make gifts to AMA of:
or with a Charitable Remainder Trust (CRT)
• Immediate income tax deduction
• Lifetime income for you and your spouse (or other
beneficiary)
• Reduction in estate taxes
• Money for your favorite charities
Interested? Contact AMA Executive Director Joyce Hager at
(765) 287-1256, extension 200.
Cash
Securities
Insurance
Gems
Real Estate
Etc.
07sig5.QXD 4/23/04 10:08 am Page 144
July 2004 145
Micro-Mark has more than 2,600 name-brand and
hard-to-find tools and accessories…many at discount
prices. You’ll complete your projects in less time
with more professional results!
340-3274 Snyder Avenue
Berkeley Heights, NJ 07922-1538
NAME
ADDRESS
CITY
STATE ZIP
To order our catalog, send $1 and this coupon to:
1-800-225-1066 • www.micromark.com
®
Please say you saw our ad in the July issue of Model Aviation.
MICRO-MARK’S
got it !
#83099
“STAND-IN” HOLDER FOR LARGE SCALE MODELS
OVER A DOZEN MODELS OF WWI, WWII, AND CLASSIC CIVILIAN
AIRCRAFT AVAILABLE WITH MORE VERSIONS TO FOLLOW!
• Electric motor(s) with prop and gear reduction included.
• Highly prefabricated for very short building times.
• 3-4 functions: rudder, aileron & elevator (rudder & ailerons on
one servo, or on separate servos.)
• Laser-cut wood parts for an accurate fit.
• Propeller and spinner included.
• Landing gear and wheels included.
(some kits have removable gear for grass field flying.)
• Contact your local hobby shop, or order direct at: www.djaerotech.com
Ryan ST / PT-16
Wingspan: 28.1 in. • Length: 20.2 in.
Weight: 4.5-5.5 oz. (ready to fly)
Wing Loading: 5.5-6.7 oz/sq. ft.
We
carry
E-tec Li-Poly
batteries &
chargers
Single motor WWII kits ....$48.95
Lockheed P-38...............$56.95
Curtiss Jenny .................$64.95
Sopwith Camel...............$72.95
Fokker Triplane ..............$73.95
DC-3 ............................$66.95
Lockheed Electra............$68.95
Piper J-3 Cub.................$51.95
Curtiss-Wright Junior.......$51.95
Ryan ST / PT-16.............$59.95
B-17F .........................$124.95
(Shipping & Handling extra)
Prices subject to
change without notice.
Visit the AMA Education Committee
Web site at www.buildandfly.com.
bellcrank leadouts are installed wholly
within the wing structure. This installation is
most desirable because it provides the
cleanest appearance of all the types and
allows the builder to incorporate full cockpit
details if so desired.
Although I have discussed keeping that
straight-line path of the control system,
many modelers’ experiences have shown
that the small amount of dihedral in most
“Low Wing-B”-type airplanes has little or no
ill effect on this kind of model’s stability and
flying attitude. I suppose the only drawback
would be the limited access you would have
to the bellcrank, etc. for adjustments and
repair. Your control-system installation
would have to be extremely good before
completing the model.
In the coming months I’ll make an effort
to cover more of the things that might be
considered “basic.”
Contest Activity: The Garden State Circle
Burners (GSCB) will be holding its annual
CL Scale Meet September 12, 2004, at the
club field. Events will include Precision,
Sport, Profile, Team, and Fun Scale.
For full contest details, field location, and
special event rules, contact the GSCB in care
of Mary Knight, 51 Ringwood Ave.,
Pompton Lakes NJ 07442.
Please send ideas, notice of upcoming CL
Scale events, contest reports, and especially
photos of CL Scale activity to me at the
address at the top of this column. MA
07sig5.QXD 4/23/04 10:08 am Page 145
Edition: Model Aviation - 2004/07
Page Numbers: 142,143,144,145
142 MODEL AVIATION
CONTROL LINE SCALE
Bill Boss, 77-06 269th St., New Hyde Park NY 11040
IT HAS BEEN quite some time since I
covered some of the basics associated with
building our Scale models. I know that what
I will write about may be old news to many
of our advanced CL modelers (Scale or
otherwise), but there is always a new group
of modelers coming along, and some of
what I write here may be beneficial to them.
This month I’m going to review the
many ways in which CL-model leadouts can
be installed. The accompanying sketch
shows the various ways in which the
leadouts may be mounted or anchored in/to
our models.
You might ask why there is so much
concern about how the leadouts are installed.
What is the purpose of the leadouts? Do they
have to be installed in any particular manner
to keep the model stable in flight? What
types of supports are used to hold the
leadouts in place? What effect does the
leadout and bellcrank placement have on the
scale interior of the model? And what are
the rules regarding the use of removable
leadout guides on our Scale models?
The answer to the first question is that
the leadouts provide a means by which we
attach the flying lines to the model’s
bellcrank. The placement of the bellcrank
and leadouts will depend on the type of
airplane you are building: biplane, highwing,
low-wing, or midwing configuration.
When installing the leadouts and
bellcrank, we make every effort to create a
straight line from the control handle through
the lines to the bellcrank. This depends on
the bellcrank being mounted at, or near, the
Bellcrank installation (L) and removable leadout guide (R) in Mike Welshans’ Rearwin Speedster. Welshans photos.
This month’s column explores various leadout and guide placements for CL Scale
models. The text contains details on each type. Sketch by the author.
07sig5.QXD 4/23/04 10:07 am Page 142
model’s vertical CG. The straight-line path
provides the best chance of having a
smooth-operating control system that will
provide a level and stable flight attitude.
To achieve a good flight attitude and
control, the leadouts must be supported in
some manner near the tip of the inboard
wing. If the leadouts are not supported at
the inboard wingtip, the model will most
likely fly in an erratic manner, and we will
end up with some disastrous consequences.
The sketch shows several of the most
common methods of installing the leadouts.
The first two illustrations show how we
might support the leadouts in biplane and
high-wing models, both of which present
problems because there is no easy way to
hide the leadouts to provide clean-looking
models for competition and static judging.
In the biplane, the leadouts are
generally supported by placing a plywood
or sheet-metal piece attached to the struts
between the upper and lower wing. The
support is best located at a point on the
struts that is approximately one-third to
one-half the distance between the upper
and lower wing when measured from the
upper surface of the bottom wing.
In the high-wing model, the leadouts are
generally supported by a device shaped
from piano wire that is secured to a rib near
the wing’s inboard tip. The length of the
support is governed by where the bellcrank
is mounted in the model’s fuselage.
Remember that you want to maintain a
straight line from handle to bellcrank and
for the leadouts to remain parallel to the
lower surface of the model’s wing.
The “Low Wing-A” and “Mid-Wing”
sketches show how the leadouts and
leadout guide might be installed on those
models. Again, the location of the bellcrank
and general use of the model might dictate
the manner in which the leadouts and guide
are installed.
The low-wing and midwing sketches
July 2004 143
All engines feature front and rear NOVAROSSI patented displaced ball bearings.
Engines are ABC design and use special alloy aluminum piston running in a hard chromed
brass alloy sleeve. Manufactured in Italy. Specifications supplied by manufacturer.
NOVAROSSI aircraft engines are distributed in the US by PlanetHobby.com, Inc.
Pipes • Manifolds • Glow Plugs • Parts • Accessories in Stock 7477 Wood Rail Cove • Memphis,TN 38119
RX21FR .21 Turbo Speed Engine.
3 exhaust & 7 intake ports. 2.2 hp at 34,300
rpm.Wt. 11.6oz. R/C or Venturi.Turbo plug.
List $500.
RX21F/N .21 Turbo Speed Engine.
1 exhaust & 4 intake ports. 2.2 hp at 34,300
rpm. Wt. 11.6oz. R/C or Venturi. Turbo plug.
Lower timed for operations without a tuned
pipe. List $400. (not shown)
C61F .60 Aircraft Engine.
1 exhaust & 3 intake ports 2.45
hp at 17,000 rpm.Wt. 22.3oz.
R/C carb with in-flight mixture
control. List $475.
FX15TC .15 Turbo Aircraft Engine
1 exhaust & 8 intake ports. 1.3hp at 34,000
rpm.Wt. 9.2oz. R/C carb or Venturi.Turbo
plug. List $300.
FX15C .15 Aircraft Engine.
1 exhaust & 3 intake ports 1.2 hp at
33,000 rpm.Wt 9.2oz. R/C carb or
Venturi. List $350.
PlanetHobby.com, Inc.
(901) 755-1536
Catalogs Upon Request • Dealer Program
Muffled and Tuned Pipes
Turbo Glow
Plug
Turbo Crank
Optional Exhaust
Manifolds
Advanced Porting
and Piston Design
sale $159
sale $229
sale $219
sale $199
NOVAROSSI Rear Exhaust Engines
email:
SUMMER SALE!
Order on our secure website:
www.planethobby.com
[email protected]
Sale ENDS Sept. 20, 2004
NOVAROSSI
Performance Innovations
sale $189
07sig5.QXD 4/23/04 10:08 am Page 143
show the guide as a fixed plywood piece
installed at a point close to the model’s
inboard wingtip. If the model will be used
for general fun-flying and its aesthetics is
not a factor, the “Low Wing-A” installation
might be acceptable.
However, if the aircraft is to be used for
competition, the “Mid-Wing” installation
might be in order. In this case, the bellcrank
can be installed low in the fuselage, and
only a small portion of the leadouts would
be visible under the wing.
Also shown in the drawing is the option
of a removable leadout guide. This could be
used in place of the fixed type shown. You
could make a removable guide from sheet
aluminum, brass, or copper, and it would
144 MODEL AVIATION
require that you install a piece of metal or
nuts at an appropriate rib location into which
you could thread small screws to hold the
removable guide in place.
A good example of a removable leadout
guide used on a high-wing model is in Mike
Welshans’ Rearwin Speedster. He entered it
in the 2003 Nats, and I featured the model in
the January 2004 column.
One of this month’s photos shows the
three-line bellcrank mounted in the bottom
of the Speedster’s fuselage. The other photo
shows the removable leadout guide made
long enough to keep that straight-line path
of the control system I mentioned earlier
while maintaining the leadouts parallel with
the bottom of the upper wing. Although it
might be obvious to many, using a
removable guide requires the use of stranded
wire leadouts.
It would seem that with a little ingenuity
and planning, you could improve almost any
CL Scale competition model’s appearance
by using stranded wire leadouts and
removable guides. Most World War II
fighters and bombers certainly lend
themselves to this idea; there are areas on
the airplanes’ wings and fuselages in which
removable panels might be made for storing
coiled leadouts until ready for flight.
You could also apply that idea to the
biplane and high-wing types, in which a
finely executed removable fuselage panel
could be used to store the leadouts. The
object of all this is to provide the cleanestlooking
model for static judging.
You can find rules on using removable
leadout guides in AMA’s Competition
Regulations. For CL Precision Scale, the
“Unified Scale Judging Regulations” (Page
153, paragraph 6, item f) state that leadout
guides may be removed for static judging
and reinstalled before flight.
In the Sport Scale event, permission to
use removable leadout guides is covered
under “Static Judging” (page 160, paragraph
5.5, item e). Since the CL Designer and
Profile Scale rules are based on the Sport
Scale rules, using removable leadout guides
is also permissible in those events.
The last of the small drawings is “Low
Wing-B.” In this type of installation, the
master
airscrew
Windsor Propeller Co.
P.O. Box 250, Rancho Cordova,
CA 95741-0250
ph. 916.631.8385
email. [email protected]
The K Series
has been
redeisgned
with:
•Slightly
rounded tips
•Thinner
blades with a
bit more blade
area.
•Noticeable
performance
improvement
for both 2 and
4-stroke engines.
•Lower pitches
for aerobatic
and hovering
maneuvers.
Sizes
12x4, 12x5, $ 3.19
12x6, 12x8 $ 3.19
13x5, 13x6, $ 4.29
13x8 $ 4.29
14x6, 14x8 $ 5.99
15x6, 15x8 $ 7.59
16x8, 16x8 $ 8.29
New
K Series
Planned Giving to AMA
You may make gifts to AMA of:
or with a Charitable Remainder Trust (CRT)
• Immediate income tax deduction
• Lifetime income for you and your spouse (or other
beneficiary)
• Reduction in estate taxes
• Money for your favorite charities
Interested? Contact AMA Executive Director Joyce Hager at
(765) 287-1256, extension 200.
Cash
Securities
Insurance
Gems
Real Estate
Etc.
07sig5.QXD 4/23/04 10:08 am Page 144
July 2004 145
Micro-Mark has more than 2,600 name-brand and
hard-to-find tools and accessories…many at discount
prices. You’ll complete your projects in less time
with more professional results!
340-3274 Snyder Avenue
Berkeley Heights, NJ 07922-1538
NAME
ADDRESS
CITY
STATE ZIP
To order our catalog, send $1 and this coupon to:
1-800-225-1066 • www.micromark.com
®
Please say you saw our ad in the July issue of Model Aviation.
MICRO-MARK’S
got it !
#83099
“STAND-IN” HOLDER FOR LARGE SCALE MODELS
OVER A DOZEN MODELS OF WWI, WWII, AND CLASSIC CIVILIAN
AIRCRAFT AVAILABLE WITH MORE VERSIONS TO FOLLOW!
• Electric motor(s) with prop and gear reduction included.
• Highly prefabricated for very short building times.
• 3-4 functions: rudder, aileron & elevator (rudder & ailerons on
one servo, or on separate servos.)
• Laser-cut wood parts for an accurate fit.
• Propeller and spinner included.
• Landing gear and wheels included.
(some kits have removable gear for grass field flying.)
• Contact your local hobby shop, or order direct at: www.djaerotech.com
Ryan ST / PT-16
Wingspan: 28.1 in. • Length: 20.2 in.
Weight: 4.5-5.5 oz. (ready to fly)
Wing Loading: 5.5-6.7 oz/sq. ft.
We
carry
E-tec Li-Poly
batteries &
chargers
Single motor WWII kits ....$48.95
Lockheed P-38...............$56.95
Curtiss Jenny .................$64.95
Sopwith Camel...............$72.95
Fokker Triplane ..............$73.95
DC-3 ............................$66.95
Lockheed Electra............$68.95
Piper J-3 Cub.................$51.95
Curtiss-Wright Junior.......$51.95
Ryan ST / PT-16.............$59.95
B-17F .........................$124.95
(Shipping & Handling extra)
Prices subject to
change without notice.
Visit the AMA Education Committee
Web site at www.buildandfly.com.
bellcrank leadouts are installed wholly
within the wing structure. This installation is
most desirable because it provides the
cleanest appearance of all the types and
allows the builder to incorporate full cockpit
details if so desired.
Although I have discussed keeping that
straight-line path of the control system,
many modelers’ experiences have shown
that the small amount of dihedral in most
“Low Wing-B”-type airplanes has little or no
ill effect on this kind of model’s stability and
flying attitude. I suppose the only drawback
would be the limited access you would have
to the bellcrank, etc. for adjustments and
repair. Your control-system installation
would have to be extremely good before
completing the model.
In the coming months I’ll make an effort
to cover more of the things that might be
considered “basic.”
Contest Activity: The Garden State Circle
Burners (GSCB) will be holding its annual
CL Scale Meet September 12, 2004, at the
club field. Events will include Precision,
Sport, Profile, Team, and Fun Scale.
For full contest details, field location, and
special event rules, contact the GSCB in care
of Mary Knight, 51 Ringwood Ave.,
Pompton Lakes NJ 07442.
Please send ideas, notice of upcoming CL
Scale events, contest reports, and especially
photos of CL Scale activity to me at the
address at the top of this column. MA
07sig5.QXD 4/23/04 10:08 am Page 145
Edition: Model Aviation - 2004/07
Page Numbers: 142,143,144,145
142 MODEL AVIATION
CONTROL LINE SCALE
Bill Boss, 77-06 269th St., New Hyde Park NY 11040
IT HAS BEEN quite some time since I
covered some of the basics associated with
building our Scale models. I know that what
I will write about may be old news to many
of our advanced CL modelers (Scale or
otherwise), but there is always a new group
of modelers coming along, and some of
what I write here may be beneficial to them.
This month I’m going to review the
many ways in which CL-model leadouts can
be installed. The accompanying sketch
shows the various ways in which the
leadouts may be mounted or anchored in/to
our models.
You might ask why there is so much
concern about how the leadouts are installed.
What is the purpose of the leadouts? Do they
have to be installed in any particular manner
to keep the model stable in flight? What
types of supports are used to hold the
leadouts in place? What effect does the
leadout and bellcrank placement have on the
scale interior of the model? And what are
the rules regarding the use of removable
leadout guides on our Scale models?
The answer to the first question is that
the leadouts provide a means by which we
attach the flying lines to the model’s
bellcrank. The placement of the bellcrank
and leadouts will depend on the type of
airplane you are building: biplane, highwing,
low-wing, or midwing configuration.
When installing the leadouts and
bellcrank, we make every effort to create a
straight line from the control handle through
the lines to the bellcrank. This depends on
the bellcrank being mounted at, or near, the
Bellcrank installation (L) and removable leadout guide (R) in Mike Welshans’ Rearwin Speedster. Welshans photos.
This month’s column explores various leadout and guide placements for CL Scale
models. The text contains details on each type. Sketch by the author.
07sig5.QXD 4/23/04 10:07 am Page 142
model’s vertical CG. The straight-line path
provides the best chance of having a
smooth-operating control system that will
provide a level and stable flight attitude.
To achieve a good flight attitude and
control, the leadouts must be supported in
some manner near the tip of the inboard
wing. If the leadouts are not supported at
the inboard wingtip, the model will most
likely fly in an erratic manner, and we will
end up with some disastrous consequences.
The sketch shows several of the most
common methods of installing the leadouts.
The first two illustrations show how we
might support the leadouts in biplane and
high-wing models, both of which present
problems because there is no easy way to
hide the leadouts to provide clean-looking
models for competition and static judging.
In the biplane, the leadouts are
generally supported by placing a plywood
or sheet-metal piece attached to the struts
between the upper and lower wing. The
support is best located at a point on the
struts that is approximately one-third to
one-half the distance between the upper
and lower wing when measured from the
upper surface of the bottom wing.
In the high-wing model, the leadouts are
generally supported by a device shaped
from piano wire that is secured to a rib near
the wing’s inboard tip. The length of the
support is governed by where the bellcrank
is mounted in the model’s fuselage.
Remember that you want to maintain a
straight line from handle to bellcrank and
for the leadouts to remain parallel to the
lower surface of the model’s wing.
The “Low Wing-A” and “Mid-Wing”
sketches show how the leadouts and
leadout guide might be installed on those
models. Again, the location of the bellcrank
and general use of the model might dictate
the manner in which the leadouts and guide
are installed.
The low-wing and midwing sketches
July 2004 143
All engines feature front and rear NOVAROSSI patented displaced ball bearings.
Engines are ABC design and use special alloy aluminum piston running in a hard chromed
brass alloy sleeve. Manufactured in Italy. Specifications supplied by manufacturer.
NOVAROSSI aircraft engines are distributed in the US by PlanetHobby.com, Inc.
Pipes • Manifolds • Glow Plugs • Parts • Accessories in Stock 7477 Wood Rail Cove • Memphis,TN 38119
RX21FR .21 Turbo Speed Engine.
3 exhaust & 7 intake ports. 2.2 hp at 34,300
rpm.Wt. 11.6oz. R/C or Venturi.Turbo plug.
List $500.
RX21F/N .21 Turbo Speed Engine.
1 exhaust & 4 intake ports. 2.2 hp at 34,300
rpm. Wt. 11.6oz. R/C or Venturi. Turbo plug.
Lower timed for operations without a tuned
pipe. List $400. (not shown)
C61F .60 Aircraft Engine.
1 exhaust & 3 intake ports 2.45
hp at 17,000 rpm.Wt. 22.3oz.
R/C carb with in-flight mixture
control. List $475.
FX15TC .15 Turbo Aircraft Engine
1 exhaust & 8 intake ports. 1.3hp at 34,000
rpm.Wt. 9.2oz. R/C carb or Venturi.Turbo
plug. List $300.
FX15C .15 Aircraft Engine.
1 exhaust & 3 intake ports 1.2 hp at
33,000 rpm.Wt 9.2oz. R/C carb or
Venturi. List $350.
PlanetHobby.com, Inc.
(901) 755-1536
Catalogs Upon Request • Dealer Program
Muffled and Tuned Pipes
Turbo Glow
Plug
Turbo Crank
Optional Exhaust
Manifolds
Advanced Porting
and Piston Design
sale $159
sale $229
sale $219
sale $199
NOVAROSSI Rear Exhaust Engines
email:
SUMMER SALE!
Order on our secure website:
www.planethobby.com
[email protected]
Sale ENDS Sept. 20, 2004
NOVAROSSI
Performance Innovations
sale $189
07sig5.QXD 4/23/04 10:08 am Page 143
show the guide as a fixed plywood piece
installed at a point close to the model’s
inboard wingtip. If the model will be used
for general fun-flying and its aesthetics is
not a factor, the “Low Wing-A” installation
might be acceptable.
However, if the aircraft is to be used for
competition, the “Mid-Wing” installation
might be in order. In this case, the bellcrank
can be installed low in the fuselage, and
only a small portion of the leadouts would
be visible under the wing.
Also shown in the drawing is the option
of a removable leadout guide. This could be
used in place of the fixed type shown. You
could make a removable guide from sheet
aluminum, brass, or copper, and it would
144 MODEL AVIATION
require that you install a piece of metal or
nuts at an appropriate rib location into which
you could thread small screws to hold the
removable guide in place.
A good example of a removable leadout
guide used on a high-wing model is in Mike
Welshans’ Rearwin Speedster. He entered it
in the 2003 Nats, and I featured the model in
the January 2004 column.
One of this month’s photos shows the
three-line bellcrank mounted in the bottom
of the Speedster’s fuselage. The other photo
shows the removable leadout guide made
long enough to keep that straight-line path
of the control system I mentioned earlier
while maintaining the leadouts parallel with
the bottom of the upper wing. Although it
might be obvious to many, using a
removable guide requires the use of stranded
wire leadouts.
It would seem that with a little ingenuity
and planning, you could improve almost any
CL Scale competition model’s appearance
by using stranded wire leadouts and
removable guides. Most World War II
fighters and bombers certainly lend
themselves to this idea; there are areas on
the airplanes’ wings and fuselages in which
removable panels might be made for storing
coiled leadouts until ready for flight.
You could also apply that idea to the
biplane and high-wing types, in which a
finely executed removable fuselage panel
could be used to store the leadouts. The
object of all this is to provide the cleanestlooking
model for static judging.
You can find rules on using removable
leadout guides in AMA’s Competition
Regulations. For CL Precision Scale, the
“Unified Scale Judging Regulations” (Page
153, paragraph 6, item f) state that leadout
guides may be removed for static judging
and reinstalled before flight.
In the Sport Scale event, permission to
use removable leadout guides is covered
under “Static Judging” (page 160, paragraph
5.5, item e). Since the CL Designer and
Profile Scale rules are based on the Sport
Scale rules, using removable leadout guides
is also permissible in those events.
The last of the small drawings is “Low
Wing-B.” In this type of installation, the
master
airscrew
Windsor Propeller Co.
P.O. Box 250, Rancho Cordova,
CA 95741-0250
ph. 916.631.8385
email. [email protected]
The K Series
has been
redeisgned
with:
•Slightly
rounded tips
•Thinner
blades with a
bit more blade
area.
•Noticeable
performance
improvement
for both 2 and
4-stroke engines.
•Lower pitches
for aerobatic
and hovering
maneuvers.
Sizes
12x4, 12x5, $ 3.19
12x6, 12x8 $ 3.19
13x5, 13x6, $ 4.29
13x8 $ 4.29
14x6, 14x8 $ 5.99
15x6, 15x8 $ 7.59
16x8, 16x8 $ 8.29
New
K Series
Planned Giving to AMA
You may make gifts to AMA of:
or with a Charitable Remainder Trust (CRT)
• Immediate income tax deduction
• Lifetime income for you and your spouse (or other
beneficiary)
• Reduction in estate taxes
• Money for your favorite charities
Interested? Contact AMA Executive Director Joyce Hager at
(765) 287-1256, extension 200.
Cash
Securities
Insurance
Gems
Real Estate
Etc.
07sig5.QXD 4/23/04 10:08 am Page 144
July 2004 145
Micro-Mark has more than 2,600 name-brand and
hard-to-find tools and accessories…many at discount
prices. You’ll complete your projects in less time
with more professional results!
340-3274 Snyder Avenue
Berkeley Heights, NJ 07922-1538
NAME
ADDRESS
CITY
STATE ZIP
To order our catalog, send $1 and this coupon to:
1-800-225-1066 • www.micromark.com
®
Please say you saw our ad in the July issue of Model Aviation.
MICRO-MARK’S
got it !
#83099
“STAND-IN” HOLDER FOR LARGE SCALE MODELS
OVER A DOZEN MODELS OF WWI, WWII, AND CLASSIC CIVILIAN
AIRCRAFT AVAILABLE WITH MORE VERSIONS TO FOLLOW!
• Electric motor(s) with prop and gear reduction included.
• Highly prefabricated for very short building times.
• 3-4 functions: rudder, aileron & elevator (rudder & ailerons on
one servo, or on separate servos.)
• Laser-cut wood parts for an accurate fit.
• Propeller and spinner included.
• Landing gear and wheels included.
(some kits have removable gear for grass field flying.)
• Contact your local hobby shop, or order direct at: www.djaerotech.com
Ryan ST / PT-16
Wingspan: 28.1 in. • Length: 20.2 in.
Weight: 4.5-5.5 oz. (ready to fly)
Wing Loading: 5.5-6.7 oz/sq. ft.
We
carry
E-tec Li-Poly
batteries &
chargers
Single motor WWII kits ....$48.95
Lockheed P-38...............$56.95
Curtiss Jenny .................$64.95
Sopwith Camel...............$72.95
Fokker Triplane ..............$73.95
DC-3 ............................$66.95
Lockheed Electra............$68.95
Piper J-3 Cub.................$51.95
Curtiss-Wright Junior.......$51.95
Ryan ST / PT-16.............$59.95
B-17F .........................$124.95
(Shipping & Handling extra)
Prices subject to
change without notice.
Visit the AMA Education Committee
Web site at www.buildandfly.com.
bellcrank leadouts are installed wholly
within the wing structure. This installation is
most desirable because it provides the
cleanest appearance of all the types and
allows the builder to incorporate full cockpit
details if so desired.
Although I have discussed keeping that
straight-line path of the control system,
many modelers’ experiences have shown
that the small amount of dihedral in most
“Low Wing-B”-type airplanes has little or no
ill effect on this kind of model’s stability and
flying attitude. I suppose the only drawback
would be the limited access you would have
to the bellcrank, etc. for adjustments and
repair. Your control-system installation
would have to be extremely good before
completing the model.
In the coming months I’ll make an effort
to cover more of the things that might be
considered “basic.”
Contest Activity: The Garden State Circle
Burners (GSCB) will be holding its annual
CL Scale Meet September 12, 2004, at the
club field. Events will include Precision,
Sport, Profile, Team, and Fun Scale.
For full contest details, field location, and
special event rules, contact the GSCB in care
of Mary Knight, 51 Ringwood Ave.,
Pompton Lakes NJ 07442.
Please send ideas, notice of upcoming CL
Scale events, contest reports, and especially
photos of CL Scale activity to me at the
address at the top of this column. MA
07sig5.QXD 4/23/04 10:08 am Page 145