100 MODEL AVIATION
[[email protected]]
Radio Control Soaring Lee Estingoy
The Soaring wonders of Don Peters
Don Peters is the owner of Maple Leaf
Design, which develops popular Unlimited
Soaring models such as the Icon and now
the Icon 2.
Daryl Perkins hits a perfect bull’s-eye at Visalia, California; it can’t be done better.
Landing points are often the defining challenge among high-ranking Soaring pilots.
HI, GROUP! My name is Lee and I’m a
Soaring addict. Today we have a special
treat; master airframer Don Peters, the man
behind Maple Leaf Design, has been kind
enough to share some of his thoughts and
experiences with us.
Don’s models, most notably the Icon,
have led the trend toward larger competition
gliders. His latest design, the Icon 2,
represents the best in US model sailplane
design and building artistry.
LE: How long have you been making
models commercially? Is this your day job?
DP: I built my first commercial sailplane
about 15 years ago. After about two years I
had a significant backorder—enough to quit
my real job and build airplanes full-time.
LE: How have the building processes
changed since then? Has it been hard to
adapt?
DP: In those early days, “[vacuum-]bagged”
wings were cutting edge. The technology
was pretty simple, and the designs adapted
well. You needed some light E glass, a tiny
1/6-horsepower vacuum pump, and some 14-
mil Mylar, and you were a state-of-the-art
builder.
I began building hollow molded wings
for the 2-meter Image after doing about 50
of them with bagged wings.
I remember being really surprised that
molded wings are actually heavier than
bagged wings. Molded wings weren’t that
hard to adapt to, but they do require a lot
more tooling and equipment. And, while you
can take molds from hand-built masters, it
makes a lot more sense to use computercontrolled
machines.
LE: I would imagine that new-sailplane
development is evolutionary, but the Icon
and Icon 2 seem to be dramatically different
from the models that the European
manufacturers make. Are your models
designed to play the same game? Why the
differences?
DP: The original Icon was certainly bigger
than the Euro sailplanes at the time. In those
days—about 12 years ago—it was thought
that larger airplanes wouldn’t launch. The
Icon was designed by Joe Wurtz, who was
convinced that that was nonsense, and he
was right. The Icon 2 follows that trend,
again mostly at the suggestion of the
designer, Mark Drela.
Bigger sailplanes have a number of
inherent advantages; they are more
efficient—they have less drag, they cover
more ground, and they’re easier to see. They
launch just as well, although they are harder
on towlines, and they can land just as well.
LE: How do you go about prototyping a
sailplane? Don’t molded models require a
substantial investment in plugs and molds?
How can you make changes to the design?
DP: I remember asking Joe Wurtz if he
thought it made sense to test the Icon design
by building a six- or eight-panel bagged
wing. He replied that the increased drag
losses built into such a prototype would
negate its testing value. And the model
market is way too small to do the kind of
initial research and development that
companies like Boeing or Lockheed could
afford.
So, as a model builder, you have to take
several significant up-front risks. The
tooling is so expensive and my company is
so small that I have to commit to the best
design thinking I can find and then work
with it to get the desired result.
We were unbelievably lucky with the
Icon. It probably could have benefited from
a larger horizontal stabilizer, but nobody felt
strongly enough to actually do anything
about it.
The Icon 2 has been a very different
experience. While the wing was just about
perfect—we haven’t made any changes to
it—the fuselage and empennage have
required quite a bit of development work to
get it to the level required for international
competition.
This is expensive because the
engineering is almost totally iterative—you
develop the idea, then you build the
necessary tooling, then you test the plane
with the new part. From that you learn what
you should have done, then you start the
process again. You often destroy some part
or all of a plane in each iteration, then throw
away the new tooling too, just to add insult
to injury.
The Icon 2 has required two years and
09sig4x_00MSTRPG.QXD 7/23/10 9:40 AM Page 100
molds, two rudder
molds, four stabilizer
molds, and three nose cone
molds—all with numerous builds.
The project has benefited from lots of
time and valued input from probably 50
committed clients, including four world
champions. But I’m still using the original
wing mold; thank you, Mark Drela.
LE: What sort of aerodynamic design work is
done on your models?
DP: Here, again,
we all need to thank Mark
Drela. Mark is a professor of
aerodynamics at MIT (Massachusetts
Institute of Technology). He is also quite a
good sailplane pilot and one of the best model
builders I know.
Years ago he developed a computer
program called X-foil, to predict the
performance of airfoils. He released it to the
public domain so everyone with the smarts
to understand it could use it essentially free.
Joe used it running on the big computers
at Lockheed’s Skunk Works to design the
original Icon airfoils. Mark used it to design
the AG series of airfoils, which are used in
the Icon 2. He was also responsible for the
Icon 2 planform; i.e., he did the whole wing.
LE: There are a lot of us duffers out there
who somehow manage to get a world-class
sailplane in our hands. From your unique
perspective, what is the best thing a clublevel
pilot can do to improve his or her
skills and performance? How much is the
model and how much is the pilot?
DP: I’m a great believer in buying the
best equipment you can afford, then
flying the bejesus out of it until you
really learn it. In fact, that’s what guys
like Cody [Remington] and Daryl
[Perkins] do. And they practice a lot
more, and they’re way better pilots than
the rest of us, so they really learn a plane.
Certainly it’s the pilot.
But it’s also worth noting that the hot
pilots can all pretty much fly what they
want, so they’re flying planes that perform
well and are suited to their flying styles.
LE: What is your favorite sailplane to fly
for fun these days?
DP: I’m a dyed-in-the-wool hand-launch
junkie. I still have the most fun chasing
small thermals with my beat-up 6-year-old
Encore.
LE: What is your Rosebud, or sailplane
that left the biggest mark on you?
DP: I guess it’s got to be the Icon 2
because of the increased performance and
structural issues involved in such a big
plane. I’ve learned more from the project
than any other I’ve been involved with.
As originally delivered, it was a decent
plane, but it wasn’t all that easy to fly well.
I’m not a very good pilot, but I’m pretty
observant, and I could see flashes of
brilliance, but there was some stuff that
needed to be sorted out.
The tailboom was flexing too much on
launch, so we retooled the fuselage. Skip
Miller got involved early on; he
identified the need for a much bigger
horizontal stabilizer—like 60% bigger.
Well, those great big stabilizers had
flutter issues. By the time we sorted that
out, the fins developed flutter issues. We
initially solved the flutter problems by just
simply building heavier parts—hardly an
elegant solution.
By this time Daryl Perkins was flying the
plane, and he brought a four-time World
Champion’s perspective to the project. So
we spent months fine-tuning the build.
Ultimately we developed a stronger, stiffer
3.8-meter airframe that weighs about the
same as a 3.3-meter airframe.
LE: How many man-hours are required to
build a modern molded sailplane once it’s
in production?
DP: It takes about 10 working days to
build an Icon 2. Compare that to about six
working days to build the original Icon.
LE: Any words of wisdom you’d like to
pass on to the Soaring community?
DP: I don’t know that I have much
wisdom. I always reflect on Mark Twain’s
observation that good judgment comes
mostly from experience, and experience
mostly comes from bad judgment. MA
Edition: Model Aviation - 2010/09
Page Numbers: 100,101,103
Edition: Model Aviation - 2010/09
Page Numbers: 100,101,103
100 MODEL AVIATION
[[email protected]]
Radio Control Soaring Lee Estingoy
The Soaring wonders of Don Peters
Don Peters is the owner of Maple Leaf
Design, which develops popular Unlimited
Soaring models such as the Icon and now
the Icon 2.
Daryl Perkins hits a perfect bull’s-eye at Visalia, California; it can’t be done better.
Landing points are often the defining challenge among high-ranking Soaring pilots.
HI, GROUP! My name is Lee and I’m a
Soaring addict. Today we have a special
treat; master airframer Don Peters, the man
behind Maple Leaf Design, has been kind
enough to share some of his thoughts and
experiences with us.
Don’s models, most notably the Icon,
have led the trend toward larger competition
gliders. His latest design, the Icon 2,
represents the best in US model sailplane
design and building artistry.
LE: How long have you been making
models commercially? Is this your day job?
DP: I built my first commercial sailplane
about 15 years ago. After about two years I
had a significant backorder—enough to quit
my real job and build airplanes full-time.
LE: How have the building processes
changed since then? Has it been hard to
adapt?
DP: In those early days, “[vacuum-]bagged”
wings were cutting edge. The technology
was pretty simple, and the designs adapted
well. You needed some light E glass, a tiny
1/6-horsepower vacuum pump, and some 14-
mil Mylar, and you were a state-of-the-art
builder.
I began building hollow molded wings
for the 2-meter Image after doing about 50
of them with bagged wings.
I remember being really surprised that
molded wings are actually heavier than
bagged wings. Molded wings weren’t that
hard to adapt to, but they do require a lot
more tooling and equipment. And, while you
can take molds from hand-built masters, it
makes a lot more sense to use computercontrolled
machines.
LE: I would imagine that new-sailplane
development is evolutionary, but the Icon
and Icon 2 seem to be dramatically different
from the models that the European
manufacturers make. Are your models
designed to play the same game? Why the
differences?
DP: The original Icon was certainly bigger
than the Euro sailplanes at the time. In those
days—about 12 years ago—it was thought
that larger airplanes wouldn’t launch. The
Icon was designed by Joe Wurtz, who was
convinced that that was nonsense, and he
was right. The Icon 2 follows that trend,
again mostly at the suggestion of the
designer, Mark Drela.
Bigger sailplanes have a number of
inherent advantages; they are more
efficient—they have less drag, they cover
more ground, and they’re easier to see. They
launch just as well, although they are harder
on towlines, and they can land just as well.
LE: How do you go about prototyping a
sailplane? Don’t molded models require a
substantial investment in plugs and molds?
How can you make changes to the design?
DP: I remember asking Joe Wurtz if he
thought it made sense to test the Icon design
by building a six- or eight-panel bagged
wing. He replied that the increased drag
losses built into such a prototype would
negate its testing value. And the model
market is way too small to do the kind of
initial research and development that
companies like Boeing or Lockheed could
afford.
So, as a model builder, you have to take
several significant up-front risks. The
tooling is so expensive and my company is
so small that I have to commit to the best
design thinking I can find and then work
with it to get the desired result.
We were unbelievably lucky with the
Icon. It probably could have benefited from
a larger horizontal stabilizer, but nobody felt
strongly enough to actually do anything
about it.
The Icon 2 has been a very different
experience. While the wing was just about
perfect—we haven’t made any changes to
it—the fuselage and empennage have
required quite a bit of development work to
get it to the level required for international
competition.
This is expensive because the
engineering is almost totally iterative—you
develop the idea, then you build the
necessary tooling, then you test the plane
with the new part. From that you learn what
you should have done, then you start the
process again. You often destroy some part
or all of a plane in each iteration, then throw
away the new tooling too, just to add insult
to injury.
The Icon 2 has required two years and
09sig4x_00MSTRPG.QXD 7/23/10 9:40 AM Page 100
molds, two rudder
molds, four stabilizer
molds, and three nose cone
molds—all with numerous builds.
The project has benefited from lots of
time and valued input from probably 50
committed clients, including four world
champions. But I’m still using the original
wing mold; thank you, Mark Drela.
LE: What sort of aerodynamic design work is
done on your models?
DP: Here, again,
we all need to thank Mark
Drela. Mark is a professor of
aerodynamics at MIT (Massachusetts
Institute of Technology). He is also quite a
good sailplane pilot and one of the best model
builders I know.
Years ago he developed a computer
program called X-foil, to predict the
performance of airfoils. He released it to the
public domain so everyone with the smarts
to understand it could use it essentially free.
Joe used it running on the big computers
at Lockheed’s Skunk Works to design the
original Icon airfoils. Mark used it to design
the AG series of airfoils, which are used in
the Icon 2. He was also responsible for the
Icon 2 planform; i.e., he did the whole wing.
LE: There are a lot of us duffers out there
who somehow manage to get a world-class
sailplane in our hands. From your unique
perspective, what is the best thing a clublevel
pilot can do to improve his or her
skills and performance? How much is the
model and how much is the pilot?
DP: I’m a great believer in buying the
best equipment you can afford, then
flying the bejesus out of it until you
really learn it. In fact, that’s what guys
like Cody [Remington] and Daryl
[Perkins] do. And they practice a lot
more, and they’re way better pilots than
the rest of us, so they really learn a plane.
Certainly it’s the pilot.
But it’s also worth noting that the hot
pilots can all pretty much fly what they
want, so they’re flying planes that perform
well and are suited to their flying styles.
LE: What is your favorite sailplane to fly
for fun these days?
DP: I’m a dyed-in-the-wool hand-launch
junkie. I still have the most fun chasing
small thermals with my beat-up 6-year-old
Encore.
LE: What is your Rosebud, or sailplane
that left the biggest mark on you?
DP: I guess it’s got to be the Icon 2
because of the increased performance and
structural issues involved in such a big
plane. I’ve learned more from the project
than any other I’ve been involved with.
As originally delivered, it was a decent
plane, but it wasn’t all that easy to fly well.
I’m not a very good pilot, but I’m pretty
observant, and I could see flashes of
brilliance, but there was some stuff that
needed to be sorted out.
The tailboom was flexing too much on
launch, so we retooled the fuselage. Skip
Miller got involved early on; he
identified the need for a much bigger
horizontal stabilizer—like 60% bigger.
Well, those great big stabilizers had
flutter issues. By the time we sorted that
out, the fins developed flutter issues. We
initially solved the flutter problems by just
simply building heavier parts—hardly an
elegant solution.
By this time Daryl Perkins was flying the
plane, and he brought a four-time World
Champion’s perspective to the project. So
we spent months fine-tuning the build.
Ultimately we developed a stronger, stiffer
3.8-meter airframe that weighs about the
same as a 3.3-meter airframe.
LE: How many man-hours are required to
build a modern molded sailplane once it’s
in production?
DP: It takes about 10 working days to
build an Icon 2. Compare that to about six
working days to build the original Icon.
LE: Any words of wisdom you’d like to
pass on to the Soaring community?
DP: I don’t know that I have much
wisdom. I always reflect on Mark Twain’s
observation that good judgment comes
mostly from experience, and experience
mostly comes from bad judgment. MA
Edition: Model Aviation - 2010/09
Page Numbers: 100,101,103
100 MODEL AVIATION
[[email protected]]
Radio Control Soaring Lee Estingoy
The Soaring wonders of Don Peters
Don Peters is the owner of Maple Leaf
Design, which develops popular Unlimited
Soaring models such as the Icon and now
the Icon 2.
Daryl Perkins hits a perfect bull’s-eye at Visalia, California; it can’t be done better.
Landing points are often the defining challenge among high-ranking Soaring pilots.
HI, GROUP! My name is Lee and I’m a
Soaring addict. Today we have a special
treat; master airframer Don Peters, the man
behind Maple Leaf Design, has been kind
enough to share some of his thoughts and
experiences with us.
Don’s models, most notably the Icon,
have led the trend toward larger competition
gliders. His latest design, the Icon 2,
represents the best in US model sailplane
design and building artistry.
LE: How long have you been making
models commercially? Is this your day job?
DP: I built my first commercial sailplane
about 15 years ago. After about two years I
had a significant backorder—enough to quit
my real job and build airplanes full-time.
LE: How have the building processes
changed since then? Has it been hard to
adapt?
DP: In those early days, “[vacuum-]bagged”
wings were cutting edge. The technology
was pretty simple, and the designs adapted
well. You needed some light E glass, a tiny
1/6-horsepower vacuum pump, and some 14-
mil Mylar, and you were a state-of-the-art
builder.
I began building hollow molded wings
for the 2-meter Image after doing about 50
of them with bagged wings.
I remember being really surprised that
molded wings are actually heavier than
bagged wings. Molded wings weren’t that
hard to adapt to, but they do require a lot
more tooling and equipment. And, while you
can take molds from hand-built masters, it
makes a lot more sense to use computercontrolled
machines.
LE: I would imagine that new-sailplane
development is evolutionary, but the Icon
and Icon 2 seem to be dramatically different
from the models that the European
manufacturers make. Are your models
designed to play the same game? Why the
differences?
DP: The original Icon was certainly bigger
than the Euro sailplanes at the time. In those
days—about 12 years ago—it was thought
that larger airplanes wouldn’t launch. The
Icon was designed by Joe Wurtz, who was
convinced that that was nonsense, and he
was right. The Icon 2 follows that trend,
again mostly at the suggestion of the
designer, Mark Drela.
Bigger sailplanes have a number of
inherent advantages; they are more
efficient—they have less drag, they cover
more ground, and they’re easier to see. They
launch just as well, although they are harder
on towlines, and they can land just as well.
LE: How do you go about prototyping a
sailplane? Don’t molded models require a
substantial investment in plugs and molds?
How can you make changes to the design?
DP: I remember asking Joe Wurtz if he
thought it made sense to test the Icon design
by building a six- or eight-panel bagged
wing. He replied that the increased drag
losses built into such a prototype would
negate its testing value. And the model
market is way too small to do the kind of
initial research and development that
companies like Boeing or Lockheed could
afford.
So, as a model builder, you have to take
several significant up-front risks. The
tooling is so expensive and my company is
so small that I have to commit to the best
design thinking I can find and then work
with it to get the desired result.
We were unbelievably lucky with the
Icon. It probably could have benefited from
a larger horizontal stabilizer, but nobody felt
strongly enough to actually do anything
about it.
The Icon 2 has been a very different
experience. While the wing was just about
perfect—we haven’t made any changes to
it—the fuselage and empennage have
required quite a bit of development work to
get it to the level required for international
competition.
This is expensive because the
engineering is almost totally iterative—you
develop the idea, then you build the
necessary tooling, then you test the plane
with the new part. From that you learn what
you should have done, then you start the
process again. You often destroy some part
or all of a plane in each iteration, then throw
away the new tooling too, just to add insult
to injury.
The Icon 2 has required two years and
09sig4x_00MSTRPG.QXD 7/23/10 9:40 AM Page 100
molds, two rudder
molds, four stabilizer
molds, and three nose cone
molds—all with numerous builds.
The project has benefited from lots of
time and valued input from probably 50
committed clients, including four world
champions. But I’m still using the original
wing mold; thank you, Mark Drela.
LE: What sort of aerodynamic design work is
done on your models?
DP: Here, again,
we all need to thank Mark
Drela. Mark is a professor of
aerodynamics at MIT (Massachusetts
Institute of Technology). He is also quite a
good sailplane pilot and one of the best model
builders I know.
Years ago he developed a computer
program called X-foil, to predict the
performance of airfoils. He released it to the
public domain so everyone with the smarts
to understand it could use it essentially free.
Joe used it running on the big computers
at Lockheed’s Skunk Works to design the
original Icon airfoils. Mark used it to design
the AG series of airfoils, which are used in
the Icon 2. He was also responsible for the
Icon 2 planform; i.e., he did the whole wing.
LE: There are a lot of us duffers out there
who somehow manage to get a world-class
sailplane in our hands. From your unique
perspective, what is the best thing a clublevel
pilot can do to improve his or her
skills and performance? How much is the
model and how much is the pilot?
DP: I’m a great believer in buying the
best equipment you can afford, then
flying the bejesus out of it until you
really learn it. In fact, that’s what guys
like Cody [Remington] and Daryl
[Perkins] do. And they practice a lot
more, and they’re way better pilots than
the rest of us, so they really learn a plane.
Certainly it’s the pilot.
But it’s also worth noting that the hot
pilots can all pretty much fly what they
want, so they’re flying planes that perform
well and are suited to their flying styles.
LE: What is your favorite sailplane to fly
for fun these days?
DP: I’m a dyed-in-the-wool hand-launch
junkie. I still have the most fun chasing
small thermals with my beat-up 6-year-old
Encore.
LE: What is your Rosebud, or sailplane
that left the biggest mark on you?
DP: I guess it’s got to be the Icon 2
because of the increased performance and
structural issues involved in such a big
plane. I’ve learned more from the project
than any other I’ve been involved with.
As originally delivered, it was a decent
plane, but it wasn’t all that easy to fly well.
I’m not a very good pilot, but I’m pretty
observant, and I could see flashes of
brilliance, but there was some stuff that
needed to be sorted out.
The tailboom was flexing too much on
launch, so we retooled the fuselage. Skip
Miller got involved early on; he
identified the need for a much bigger
horizontal stabilizer—like 60% bigger.
Well, those great big stabilizers had
flutter issues. By the time we sorted that
out, the fins developed flutter issues. We
initially solved the flutter problems by just
simply building heavier parts—hardly an
elegant solution.
By this time Daryl Perkins was flying the
plane, and he brought a four-time World
Champion’s perspective to the project. So
we spent months fine-tuning the build.
Ultimately we developed a stronger, stiffer
3.8-meter airframe that weighs about the
same as a 3.3-meter airframe.
LE: How many man-hours are required to
build a modern molded sailplane once it’s
in production?
DP: It takes about 10 working days to
build an Icon 2. Compare that to about six
working days to build the original Icon.
LE: Any words of wisdom you’d like to
pass on to the Soaring community?
DP: I don’t know that I have much
wisdom. I always reflect on Mark Twain’s
observation that good judgment comes
mostly from experience, and experience
mostly comes from bad judgment. MA