CONTROL LINE RACING
James Holland, [email protected]
Jim Persson pits his winning Fora .15-powered Flying Clown at
the 2004 Virgil Wilbur Memorial Race. Doug Mayer photo.
Ron Duly’s Nats-winning racer has Cyclon PC6 engine. Note
custom spinner nut, tank filler and vent system. Duly photo.
2004 Nats Flying Clown winners. Back (L-R): Don Burke, Ron
Duly, Dave Hallas, Bob Whitney. Front (L-R): Jim Allen, Jason
Allen. Don Burke photo.
I’LL BEGIN MY first column for MA by thanking Bob Hunt for
giving me the chance to do this and my fellow CL Racers for
freely sharing much of the information that I will be using.
The focus this month is the National Control Line Racing
Association (NCLRA) Flying Clown event. This unofficial class
enjoys a strong following throughout the United States and was
well supported at the 2003 and 2004 AMA Nats.
To introduce the event to people who are looking to add
another airplane to their Racing stables or make a start in Racing,
I can do no better than to quote the opening statement of the event
rules (on the NCLRA Web page at www.nclra.org). It reads:
“This event is intended for all fliers and pit crews interested in
a racing event which uses a common aircraft, emphasizes both
speed and economy, and encourages the use of a wide variety of
engines.”
Clown racing features a fuel-tank size restriction (31cc
maximum) and provides a race format in which the maximum
number of laps recorded in a set time (7.5 minutes for heats and
15 minutes for finals) wins. This combination of requirements
results in an event which is interesting for the novice and veteran.
The airplanes can be built quickly, and the range of available
finishing materials allows you to end up with a distinctive (and
eye-catching) racer. Although a number of firms and individuals
have produced and sold copies of the original Flying Clown in the
past few years, the only company that currently offers a kit for
retail sale is Brodak Manufacturing.
The Brodak kit meets the NCLRA rule requirements and is
suitable for racing with limited modifications to the airframe.
Changes I usually make are to increase the length of the engine
bearers, replace the balsa LE and spars with spruce, and use 1⁄8-
inch-diameter wire for the landing gear.
I also cover the completed fuselage
and tail assembly with 1-ounce
fiberglass cloth (using a finishing resin)
and finish the wings with one of the
commercially available plastic films.
Bob Whitney recommends placing
the leadout guides closer together than
shown on the plans. (I use 3⁄4-inch
spacing but do not move the front
leadout guide any farther forward.) He
tells me that it is better to use more
wingtip weight than less (a half ounce is
not too much) if you want the model to
take off and glide well in anything more
than a moderate breeze.
Since airframe and tank size are
restricted, the most variation in Flying
Clown racers is in their engines. One of
the factors that makes the event
particularly enjoyable for me is that no
single engine has risen to dominance,
and competitive results can be obtained
with a wide range of engines that are
currently in production.
Based on my experience as a regular
competitor in this class, and the
generosity of Bob Whitney and Don
Burke in providing information about
their equipment, I offer the following
observations on engine and propeller
choice for your Clown racer project.
If you want to start racing for a
minimal cash investment but still
approach competitiveness, only two
engines are likely to meet your needs:
the Norvel .15 (ball-bearing version)
and the MVVS .15 (glow or diesel
version). Use a 7 x 5 propeller as a
starting place (7 x 6 for the diesel), and
change diameter and/or pitch as needed
to gain airspeed and laps.
For the engine-collector type or the
person who has more cash on hand,
engine options are wide open. I have
never seen a Rossi .15 (any Mark) work
really well in a Clown racer, but the
Moki Sport .15 (which has similar
specifications to a Mark II Rossi) has
been the engine of choice in this event
for a number of people.
Although the Moki Sport .15s have
been out of production for at least 10
years, you can find them at swap meets or
on the Internet. They respond well to
modified heads that use the Nelson plug,
and they like roughly 7 x 6 propellers. (I
have found the Master Airscrew 7 x 6 to
work well on this engine.)
Bob Whitney and Dave Hallas have
obtained excellent results with the Nelson
.19 engine (including a 2003 Nats win)
and typically run an APC 7 x 6 propeller.
Bob’s strategy is to start with a large
venturi to get maximum speed and then
reduce the venturi size to bring range up
to roughly 40 laps per tank.
He also told me that engine
performance varies widely with changes
in air density, so it is a good idea to test a
range of propellers to develop
combinations that work in different
weather conditions.
A power plant that is gaining notably
in popularity with the Clown-racing
crowd is the F2D Combat engine. It is
light, compact, and uses cutting-edge
technology, giving it the ability to return
fantastic performance if a little time is
invested in setting it up with the correct
head clearance and propeller. Don Burke
and Ron Duly won the 2004 Nats using a
Cyclon PC6 turning an APC 6.5 x 6
racing-series propeller, setting heat and
finals records in the process.
April 2005 159
The Fora .15 has also been used
successfully, and I believe that more
people will switch to this type of engine in
the 2005 season.
A word of caution focuses on safety.
Because the F2D engines are designed to
work best at high rpm, I strongly
recommend using a fiberglass or carbonfiber
propeller. Many of the F2D Combat
propellers have insufficient pitches for
racing purposes, but usable propellers are
available from Bolly and others.
I have experimented with a wide range
of engines on my Clown racers, from PAW
.19 diesels to Rossi .15 glows. My current
favorites are a Cipolla Combat .15 fitted
with a Nelson plug head and an “old-style”
Profi .15. Both have recorded more than
150 laps during heat races.
Don Burke and I have learned that these
engines are much more user-friendly if the
stock needle valve and spraybar assembly
is replaced with a SuperTigre .15-style
assembly. (The SuperTigre units are
usually a direct fit.)
Flying Clown is an enjoyable event that
attracts a good number of entries at most
contests. Build one and join the fun!
One of the things that I see as an
important function of this column is
keeping people up to date on developments
in Racing hardware, such as new engines,
airplanes, propellers, and those hard-tofind
bits and pieces we all need.
With that in mind, I am pleased to
announce that Bob Fogg is considering
making another production run of his
excellent mechanical fast fills. He tells me
that the deciding factor is customer
demand; if enough people show an
interest, he’ll do it.
I have ordered four of the fast fills
because they work well and are extremely
durable. (The one on my AMA Goodyear
racer is more than 12 years old and still
works perfectly.) Please E-mail me if you
are interested, and I will pass your
information along to Bob.
I welcome your comments and
suggestions and will be pleased to hear
from you via E-mail. MA
Sources:
NCLRA
601 Van Zandt County Rd. 4815
Chandler TX 75758
Brodak Manufacturing and Distributing
Co., Inc.
100 Park Ave.
Carmichaels PA 15320
Nelson Competition Engines
121 Pebble Creek Ln.
Zelienople PA 16063
Edition: Model Aviation - 2005/04
Page Numbers: 157,158,159
Edition: Model Aviation - 2005/04
Page Numbers: 157,158,159
CONTROL LINE RACING
James Holland, [email protected]
Jim Persson pits his winning Fora .15-powered Flying Clown at
the 2004 Virgil Wilbur Memorial Race. Doug Mayer photo.
Ron Duly’s Nats-winning racer has Cyclon PC6 engine. Note
custom spinner nut, tank filler and vent system. Duly photo.
2004 Nats Flying Clown winners. Back (L-R): Don Burke, Ron
Duly, Dave Hallas, Bob Whitney. Front (L-R): Jim Allen, Jason
Allen. Don Burke photo.
I’LL BEGIN MY first column for MA by thanking Bob Hunt for
giving me the chance to do this and my fellow CL Racers for
freely sharing much of the information that I will be using.
The focus this month is the National Control Line Racing
Association (NCLRA) Flying Clown event. This unofficial class
enjoys a strong following throughout the United States and was
well supported at the 2003 and 2004 AMA Nats.
To introduce the event to people who are looking to add
another airplane to their Racing stables or make a start in Racing,
I can do no better than to quote the opening statement of the event
rules (on the NCLRA Web page at www.nclra.org). It reads:
“This event is intended for all fliers and pit crews interested in
a racing event which uses a common aircraft, emphasizes both
speed and economy, and encourages the use of a wide variety of
engines.”
Clown racing features a fuel-tank size restriction (31cc
maximum) and provides a race format in which the maximum
number of laps recorded in a set time (7.5 minutes for heats and
15 minutes for finals) wins. This combination of requirements
results in an event which is interesting for the novice and veteran.
The airplanes can be built quickly, and the range of available
finishing materials allows you to end up with a distinctive (and
eye-catching) racer. Although a number of firms and individuals
have produced and sold copies of the original Flying Clown in the
past few years, the only company that currently offers a kit for
retail sale is Brodak Manufacturing.
The Brodak kit meets the NCLRA rule requirements and is
suitable for racing with limited modifications to the airframe.
Changes I usually make are to increase the length of the engine
bearers, replace the balsa LE and spars with spruce, and use 1⁄8-
inch-diameter wire for the landing gear.
I also cover the completed fuselage
and tail assembly with 1-ounce
fiberglass cloth (using a finishing resin)
and finish the wings with one of the
commercially available plastic films.
Bob Whitney recommends placing
the leadout guides closer together than
shown on the plans. (I use 3⁄4-inch
spacing but do not move the front
leadout guide any farther forward.) He
tells me that it is better to use more
wingtip weight than less (a half ounce is
not too much) if you want the model to
take off and glide well in anything more
than a moderate breeze.
Since airframe and tank size are
restricted, the most variation in Flying
Clown racers is in their engines. One of
the factors that makes the event
particularly enjoyable for me is that no
single engine has risen to dominance,
and competitive results can be obtained
with a wide range of engines that are
currently in production.
Based on my experience as a regular
competitor in this class, and the
generosity of Bob Whitney and Don
Burke in providing information about
their equipment, I offer the following
observations on engine and propeller
choice for your Clown racer project.
If you want to start racing for a
minimal cash investment but still
approach competitiveness, only two
engines are likely to meet your needs:
the Norvel .15 (ball-bearing version)
and the MVVS .15 (glow or diesel
version). Use a 7 x 5 propeller as a
starting place (7 x 6 for the diesel), and
change diameter and/or pitch as needed
to gain airspeed and laps.
For the engine-collector type or the
person who has more cash on hand,
engine options are wide open. I have
never seen a Rossi .15 (any Mark) work
really well in a Clown racer, but the
Moki Sport .15 (which has similar
specifications to a Mark II Rossi) has
been the engine of choice in this event
for a number of people.
Although the Moki Sport .15s have
been out of production for at least 10
years, you can find them at swap meets or
on the Internet. They respond well to
modified heads that use the Nelson plug,
and they like roughly 7 x 6 propellers. (I
have found the Master Airscrew 7 x 6 to
work well on this engine.)
Bob Whitney and Dave Hallas have
obtained excellent results with the Nelson
.19 engine (including a 2003 Nats win)
and typically run an APC 7 x 6 propeller.
Bob’s strategy is to start with a large
venturi to get maximum speed and then
reduce the venturi size to bring range up
to roughly 40 laps per tank.
He also told me that engine
performance varies widely with changes
in air density, so it is a good idea to test a
range of propellers to develop
combinations that work in different
weather conditions.
A power plant that is gaining notably
in popularity with the Clown-racing
crowd is the F2D Combat engine. It is
light, compact, and uses cutting-edge
technology, giving it the ability to return
fantastic performance if a little time is
invested in setting it up with the correct
head clearance and propeller. Don Burke
and Ron Duly won the 2004 Nats using a
Cyclon PC6 turning an APC 6.5 x 6
racing-series propeller, setting heat and
finals records in the process.
April 2005 159
The Fora .15 has also been used
successfully, and I believe that more
people will switch to this type of engine in
the 2005 season.
A word of caution focuses on safety.
Because the F2D engines are designed to
work best at high rpm, I strongly
recommend using a fiberglass or carbonfiber
propeller. Many of the F2D Combat
propellers have insufficient pitches for
racing purposes, but usable propellers are
available from Bolly and others.
I have experimented with a wide range
of engines on my Clown racers, from PAW
.19 diesels to Rossi .15 glows. My current
favorites are a Cipolla Combat .15 fitted
with a Nelson plug head and an “old-style”
Profi .15. Both have recorded more than
150 laps during heat races.
Don Burke and I have learned that these
engines are much more user-friendly if the
stock needle valve and spraybar assembly
is replaced with a SuperTigre .15-style
assembly. (The SuperTigre units are
usually a direct fit.)
Flying Clown is an enjoyable event that
attracts a good number of entries at most
contests. Build one and join the fun!
One of the things that I see as an
important function of this column is
keeping people up to date on developments
in Racing hardware, such as new engines,
airplanes, propellers, and those hard-tofind
bits and pieces we all need.
With that in mind, I am pleased to
announce that Bob Fogg is considering
making another production run of his
excellent mechanical fast fills. He tells me
that the deciding factor is customer
demand; if enough people show an
interest, he’ll do it.
I have ordered four of the fast fills
because they work well and are extremely
durable. (The one on my AMA Goodyear
racer is more than 12 years old and still
works perfectly.) Please E-mail me if you
are interested, and I will pass your
information along to Bob.
I welcome your comments and
suggestions and will be pleased to hear
from you via E-mail. MA
Sources:
NCLRA
601 Van Zandt County Rd. 4815
Chandler TX 75758
Brodak Manufacturing and Distributing
Co., Inc.
100 Park Ave.
Carmichaels PA 15320
Nelson Competition Engines
121 Pebble Creek Ln.
Zelienople PA 16063
Edition: Model Aviation - 2005/04
Page Numbers: 157,158,159
CONTROL LINE RACING
James Holland, [email protected]
Jim Persson pits his winning Fora .15-powered Flying Clown at
the 2004 Virgil Wilbur Memorial Race. Doug Mayer photo.
Ron Duly’s Nats-winning racer has Cyclon PC6 engine. Note
custom spinner nut, tank filler and vent system. Duly photo.
2004 Nats Flying Clown winners. Back (L-R): Don Burke, Ron
Duly, Dave Hallas, Bob Whitney. Front (L-R): Jim Allen, Jason
Allen. Don Burke photo.
I’LL BEGIN MY first column for MA by thanking Bob Hunt for
giving me the chance to do this and my fellow CL Racers for
freely sharing much of the information that I will be using.
The focus this month is the National Control Line Racing
Association (NCLRA) Flying Clown event. This unofficial class
enjoys a strong following throughout the United States and was
well supported at the 2003 and 2004 AMA Nats.
To introduce the event to people who are looking to add
another airplane to their Racing stables or make a start in Racing,
I can do no better than to quote the opening statement of the event
rules (on the NCLRA Web page at www.nclra.org). It reads:
“This event is intended for all fliers and pit crews interested in
a racing event which uses a common aircraft, emphasizes both
speed and economy, and encourages the use of a wide variety of
engines.”
Clown racing features a fuel-tank size restriction (31cc
maximum) and provides a race format in which the maximum
number of laps recorded in a set time (7.5 minutes for heats and
15 minutes for finals) wins. This combination of requirements
results in an event which is interesting for the novice and veteran.
The airplanes can be built quickly, and the range of available
finishing materials allows you to end up with a distinctive (and
eye-catching) racer. Although a number of firms and individuals
have produced and sold copies of the original Flying Clown in the
past few years, the only company that currently offers a kit for
retail sale is Brodak Manufacturing.
The Brodak kit meets the NCLRA rule requirements and is
suitable for racing with limited modifications to the airframe.
Changes I usually make are to increase the length of the engine
bearers, replace the balsa LE and spars with spruce, and use 1⁄8-
inch-diameter wire for the landing gear.
I also cover the completed fuselage
and tail assembly with 1-ounce
fiberglass cloth (using a finishing resin)
and finish the wings with one of the
commercially available plastic films.
Bob Whitney recommends placing
the leadout guides closer together than
shown on the plans. (I use 3⁄4-inch
spacing but do not move the front
leadout guide any farther forward.) He
tells me that it is better to use more
wingtip weight than less (a half ounce is
not too much) if you want the model to
take off and glide well in anything more
than a moderate breeze.
Since airframe and tank size are
restricted, the most variation in Flying
Clown racers is in their engines. One of
the factors that makes the event
particularly enjoyable for me is that no
single engine has risen to dominance,
and competitive results can be obtained
with a wide range of engines that are
currently in production.
Based on my experience as a regular
competitor in this class, and the
generosity of Bob Whitney and Don
Burke in providing information about
their equipment, I offer the following
observations on engine and propeller
choice for your Clown racer project.
If you want to start racing for a
minimal cash investment but still
approach competitiveness, only two
engines are likely to meet your needs:
the Norvel .15 (ball-bearing version)
and the MVVS .15 (glow or diesel
version). Use a 7 x 5 propeller as a
starting place (7 x 6 for the diesel), and
change diameter and/or pitch as needed
to gain airspeed and laps.
For the engine-collector type or the
person who has more cash on hand,
engine options are wide open. I have
never seen a Rossi .15 (any Mark) work
really well in a Clown racer, but the
Moki Sport .15 (which has similar
specifications to a Mark II Rossi) has
been the engine of choice in this event
for a number of people.
Although the Moki Sport .15s have
been out of production for at least 10
years, you can find them at swap meets or
on the Internet. They respond well to
modified heads that use the Nelson plug,
and they like roughly 7 x 6 propellers. (I
have found the Master Airscrew 7 x 6 to
work well on this engine.)
Bob Whitney and Dave Hallas have
obtained excellent results with the Nelson
.19 engine (including a 2003 Nats win)
and typically run an APC 7 x 6 propeller.
Bob’s strategy is to start with a large
venturi to get maximum speed and then
reduce the venturi size to bring range up
to roughly 40 laps per tank.
He also told me that engine
performance varies widely with changes
in air density, so it is a good idea to test a
range of propellers to develop
combinations that work in different
weather conditions.
A power plant that is gaining notably
in popularity with the Clown-racing
crowd is the F2D Combat engine. It is
light, compact, and uses cutting-edge
technology, giving it the ability to return
fantastic performance if a little time is
invested in setting it up with the correct
head clearance and propeller. Don Burke
and Ron Duly won the 2004 Nats using a
Cyclon PC6 turning an APC 6.5 x 6
racing-series propeller, setting heat and
finals records in the process.
April 2005 159
The Fora .15 has also been used
successfully, and I believe that more
people will switch to this type of engine in
the 2005 season.
A word of caution focuses on safety.
Because the F2D engines are designed to
work best at high rpm, I strongly
recommend using a fiberglass or carbonfiber
propeller. Many of the F2D Combat
propellers have insufficient pitches for
racing purposes, but usable propellers are
available from Bolly and others.
I have experimented with a wide range
of engines on my Clown racers, from PAW
.19 diesels to Rossi .15 glows. My current
favorites are a Cipolla Combat .15 fitted
with a Nelson plug head and an “old-style”
Profi .15. Both have recorded more than
150 laps during heat races.
Don Burke and I have learned that these
engines are much more user-friendly if the
stock needle valve and spraybar assembly
is replaced with a SuperTigre .15-style
assembly. (The SuperTigre units are
usually a direct fit.)
Flying Clown is an enjoyable event that
attracts a good number of entries at most
contests. Build one and join the fun!
One of the things that I see as an
important function of this column is
keeping people up to date on developments
in Racing hardware, such as new engines,
airplanes, propellers, and those hard-tofind
bits and pieces we all need.
With that in mind, I am pleased to
announce that Bob Fogg is considering
making another production run of his
excellent mechanical fast fills. He tells me
that the deciding factor is customer
demand; if enough people show an
interest, he’ll do it.
I have ordered four of the fast fills
because they work well and are extremely
durable. (The one on my AMA Goodyear
racer is more than 12 years old and still
works perfectly.) Please E-mail me if you
are interested, and I will pass your
information along to Bob.
I welcome your comments and
suggestions and will be pleased to hear
from you via E-mail. MA
Sources:
NCLRA
601 Van Zandt County Rd. 4815
Chandler TX 75758
Brodak Manufacturing and Distributing
Co., Inc.
100 Park Ave.
Carmichaels PA 15320
Nelson Competition Engines
121 Pebble Creek Ln.
Zelienople PA 16063