98 MODEL AVIATION
I’M SO EXCITED about our latest project that I want to share it
with you. I have been infatuated with RC Giants for approximately
20 years. In that time I have built models from kits and plans, I
scratch-built from three-views, and even put together a couple of
Giant ARFs. Imagine my joy when I actually became involved with
designing a Giant Scale model for manufacture.
During the past nine months I have been working with Larry
Sribnick, the president of SR Batteries, designing a 1⁄4-scale Fokker
Eindecker E.I. Larry is well known for his outstanding designs such
as the X250, Cutie, and AcroPro model kits. We were able to take
some of the innovative design features of these smaller models
along with the experience I have with gas-powered models and
apply it to a 100-inch-wingspan, 16-pound World War I fighter.
One of the first lessons that I had to learn was patience. It may
have only taken a couple of months to construct a one-off aircraft
for myself, but designing and building a model as a product for
others to build is quite a different task. Plans needed to be drawn,
exact-fitting balsa and light-plywood parts had to be made, and an
easy-to-follow, descriptive instruction manual had to be written.
In addition, a landing gear, a tail-skid assembly, and a cabane
assembly had to be designed, built, and tested, and an appropriate
aluminum cowling needed to be manufactured. All of this required
hundreds of hours of computer-aided design (CAD) work and
prototype development.
There were times when Larry and I agreed on certain aspects or
ideas and other times when we disagreed. In the end, all of our
discussions made for a much better finished product. We are both
proud of the outcome, although I still have problems with being
patient. Perhaps yoga would help.
It has been my experience that during construction of any model
kit, I would come to a particular step where I would say to myself,
“Why did they do it this way?” or “I could have designed this
better.” With the Eindecker, here was my opportunity. The next few
paragraphs detail some of the issues that we’ve seen as a problem or
concern and how we addressed these issues in the Eindecker.
One of the first decisions made was that the model should be
quick and easy to build and fun for anyone to fly. The Fokker
Eindecker E.I was the premier fighter early in World War I. Unlike
many of its contemporaries, it had only one wing to contend with
and a boxy fuselage. These attributes made building the kit
attractive.
Sal Calvagna, 1335 Broadway Ave., Holbrook NY 11741; E-mail: [email protected]
RADIO CONTROL GIANTS
The Aces of Iron Productions, Inc. pilot comes unpainted, and
the landing wire attachment points can be clearly seen.
The balsa cheek assemblies are constructed separately from the
fuselage in the author and Larry Sribnick’s Eindecker E.I.
The wing panel showing the composite spars and LE. The comb
is used for alignment and spacing during construction.
This shows the three firewall laminations. Two have laser cutouts
to accommodate an engine or a motor.
09sig4.QXD 6/23/04 12:54 pm Page 98
100 MODEL AVIATION
The full-scale Eindecker used wing warping and full flying
stabilizer and rudder. We used a more traditional approach and
incorporated ailerons and elevators; however, we kept the full
flying rudder. At 100 inches, the model can be entered in any of
the International Miniature Aircraft Association events including
the popular warbird categories.
Manufacturing Process: To maintain exact tolerances, we
believed the best method of design and manufacture was CAD and
micro laser-cutting. This type of process could ensure accurately
fitting parts. This became critical with the composite spar and LE
design chosen for the Eindecker wings.
Power System: Usually a model is designed with electric, gas, or
glow as the power plant of choice. We decided early in the
process that the model would be dual-powered for gas or glow
(wet) or electric (dry). We specifically designed the kit to
accommodate both systems. We chose the Zenoah G-26 for the
gas-powered version and the AXI 4130/20 brushless motor for the
electric power system. Both power the same 18 x 6 propeller.
The concern was how to make either system easy to install.
The solution was to construct the firewall from three laminations;
the first two are light plywood and the third is aircraft-grade
plywood. One light-plywood firewall is precut for the G-26 gas
engine and the other is precut for the AXI 4130/20 motor. The
builder arranges the three layers so that the chosen power system
is on top (the first layer).
The G-26 firewall is designed to accept the stock mount and
muffler, which saves the modeler from having to purchase
additional accessories. The G-26 firewall has laser cutouts for the
fuel line, vent line, and throttle pushrod. The engine installation
merely requires four blind nuts.
The completed SR Eindecker E.I is ready for flight. Field setup
has been reduced to only a few minutes. The Eindecker E.I in flight, searching for the enemy.
Big is Better and Safer too!
The IMAA is an international organization was formed April 10,
1980 to promote non-competitive, educational, safe, relaxed flying
of LARGE radio controlled model aircraft throughout the world.
We are the largest Academy of Model Aeronautics (AMA) Special
Interest Group and as such, are committed to representing the
interest of our members in AMA related matters.
Members enjoy the privilege of
participation in hundreds of Fly-ins
and Rallies each year – including
IMAA’s own Rally of Giants).
Don’t wait. Join today! For complete
membership details, visit our web site
(www.fly-imaa.org) or give us a call
toll free at – 866 366-4622.
High-Flight,
the publication of the IMAA, is
published quarterly and is sent to
all members. High-Flight is
dedicated to the advancement of
large r/c aircraft by concentrating
on new products, techniques, and
innovations developed through
the activities of IMAA Chapters
and individuals around the world.
09sig4.QXD 6/23/04 12:54 pm Page 100
September 2004 101
Wing Assembly: Having built and sanded
many Giant Scale wings, I found it timeconsuming
and difficult to make round and
true LEs. In addition, with the natural
tendency of wood spars to warp, sometimes
it is hard to build a straight wing.
The solution was to incorporate the wing
designs from the SR X250 and Cutie into
the Eindecker wing. This involved using
three 1⁄2-inch composite tubes in each wing
panel. Two are used as spars while the third
tube is used as the LE. The result is a superstrong,
straight panel that requires no
sanding of the LE.
We designed light-plywood combs that
are used during wing construction to align
and space out the ribs. After the first few
ribs are glued in place, you simply pick up
the combs and move them farther along the
wing. The result is that the wing panels
build quickly and accurately.
The aileron servos are installed on a
laser-cut servo-mount assembly. These are
nothing new, but all of them that I have seen
have the actual servo-mount butt glued to
the servo wing cover. I have seen these glue
joints separate during hard landings when an
excessive load is placed on the servo. We
went through the extra effort of having the
mount pieces keyed into the wing cover.
Fuselage: The standard stick-built fuselage
of World War I vintage has always posed
concerns, especially when joining the rear
part of the fuselage. I can’t tell you how
many “bananas” I have built. We wanted a
design that eliminated the banana problem.
We came up with laser-cut notched parts
which include the firewall, forward fuselage
sides, doublers, formers, and laser-cut servo
tray that ensure proper alignment of the
forward part of the fuselage. Our
construction method is to build one side
over the plans and then build the second
side over the first side. In this manner, the
sides are duplicates.
Empennage: In model aircraft this size, the
horizontal stabilizer is usually supported by
braces or wires. Since the Eindecker did not
have these, we needed to construct a stabilizer
that would not use support braces. As with the
wing, the solution was to use a composite
tube for the LE of the stabilizer. The tube
allows the stabilizer to flex but not break.
The elevators have the same-size
composite tubes used in the TE. All of these
tubes provide another benefit; they make
these parts ding-proof.
The remaining outlines of the stabilizer
and elevators are constructed from light
plywood and balsa laminations to make
them stronger.
The rudder is a full flying rudder. There
is no hinging on it. We were able to
incorporate a tube-in-a-tube assembly in
which the rudder rotates. The outer tube is
part of the tail-skid assembly which is
mounted directly to the fuselage.
Landing Gear: In larger RC models,
shock-absorbing landing gear is a must. The
Eindecker gear is not easy to replicate
because of its complexity and multifunction.
On the full-scale aircraft, it was designed to
accommodate wing warping and flying
wires, and absorb shock on landing.
The model was not designed for wingwarping
operation, but we still needed to
support the flying wires in the same fashion
as the full-scale Eindecker. To create a gear
that looked right, would support the flying
wires, and would provide shock-absorbing
capability, we built and tested a few designs
before we found a solution that worked
superbly. The finished product looks like an
Eindecker gear and is installed with just
four nylon straps.
The tail skid was also designed to be
shock absorbing and uses the same type of
composite tube that is in the wings and tail
feathers.
Field Setup: There are no screws or bolts
that attach the wing panels to the fuselage.
The wings are held in place by the flying
and landing wires. The full-scale
Eindecker had many of them and the
model doesn’t look right without them.
We had seen models that used clevises
and threaded couplers to secure the flying
wires. We were not satisfied with this type
of installation because it took too long to
set up at the field, and inevitably one or
more wires would come loose during
flight.
We first tested a prototype that required
six attachment points: two for the upper
cabanes and four for the flying wires on
the landing gear. Eventually we were able
to reduce this number to only four
attachment points: two above and two
below. Field setup has now been reduced
to only a few minutes.
The Eindecker represents nine months
and hundreds of hours of hard work. It was
certainly an eye-opener for me, and I am
happy that I had the opportunity to be
involved in the process. I know that it has
made me a better modeler.
I hope you’ll agree that we were able to
solve some common problems associated
with model building and that our hard
work resulted in a fast, fun-building, and
great-flying World War I RC Giant.
For color photos and flying videos, you
can visit the SR Batteries Web site at
www.srbatteries.com or call (631) 286-
0079.
See you next month. MA
09sig4.QXD 6/23/04 12:54 pm Page 101
Edition: Model Aviation - 2004/09
Page Numbers: 98,100,101
Edition: Model Aviation - 2004/09
Page Numbers: 98,100,101
98 MODEL AVIATION
I’M SO EXCITED about our latest project that I want to share it
with you. I have been infatuated with RC Giants for approximately
20 years. In that time I have built models from kits and plans, I
scratch-built from three-views, and even put together a couple of
Giant ARFs. Imagine my joy when I actually became involved with
designing a Giant Scale model for manufacture.
During the past nine months I have been working with Larry
Sribnick, the president of SR Batteries, designing a 1⁄4-scale Fokker
Eindecker E.I. Larry is well known for his outstanding designs such
as the X250, Cutie, and AcroPro model kits. We were able to take
some of the innovative design features of these smaller models
along with the experience I have with gas-powered models and
apply it to a 100-inch-wingspan, 16-pound World War I fighter.
One of the first lessons that I had to learn was patience. It may
have only taken a couple of months to construct a one-off aircraft
for myself, but designing and building a model as a product for
others to build is quite a different task. Plans needed to be drawn,
exact-fitting balsa and light-plywood parts had to be made, and an
easy-to-follow, descriptive instruction manual had to be written.
In addition, a landing gear, a tail-skid assembly, and a cabane
assembly had to be designed, built, and tested, and an appropriate
aluminum cowling needed to be manufactured. All of this required
hundreds of hours of computer-aided design (CAD) work and
prototype development.
There were times when Larry and I agreed on certain aspects or
ideas and other times when we disagreed. In the end, all of our
discussions made for a much better finished product. We are both
proud of the outcome, although I still have problems with being
patient. Perhaps yoga would help.
It has been my experience that during construction of any model
kit, I would come to a particular step where I would say to myself,
“Why did they do it this way?” or “I could have designed this
better.” With the Eindecker, here was my opportunity. The next few
paragraphs detail some of the issues that we’ve seen as a problem or
concern and how we addressed these issues in the Eindecker.
One of the first decisions made was that the model should be
quick and easy to build and fun for anyone to fly. The Fokker
Eindecker E.I was the premier fighter early in World War I. Unlike
many of its contemporaries, it had only one wing to contend with
and a boxy fuselage. These attributes made building the kit
attractive.
Sal Calvagna, 1335 Broadway Ave., Holbrook NY 11741; E-mail: [email protected]
RADIO CONTROL GIANTS
The Aces of Iron Productions, Inc. pilot comes unpainted, and
the landing wire attachment points can be clearly seen.
The balsa cheek assemblies are constructed separately from the
fuselage in the author and Larry Sribnick’s Eindecker E.I.
The wing panel showing the composite spars and LE. The comb
is used for alignment and spacing during construction.
This shows the three firewall laminations. Two have laser cutouts
to accommodate an engine or a motor.
09sig4.QXD 6/23/04 12:54 pm Page 98
100 MODEL AVIATION
The full-scale Eindecker used wing warping and full flying
stabilizer and rudder. We used a more traditional approach and
incorporated ailerons and elevators; however, we kept the full
flying rudder. At 100 inches, the model can be entered in any of
the International Miniature Aircraft Association events including
the popular warbird categories.
Manufacturing Process: To maintain exact tolerances, we
believed the best method of design and manufacture was CAD and
micro laser-cutting. This type of process could ensure accurately
fitting parts. This became critical with the composite spar and LE
design chosen for the Eindecker wings.
Power System: Usually a model is designed with electric, gas, or
glow as the power plant of choice. We decided early in the
process that the model would be dual-powered for gas or glow
(wet) or electric (dry). We specifically designed the kit to
accommodate both systems. We chose the Zenoah G-26 for the
gas-powered version and the AXI 4130/20 brushless motor for the
electric power system. Both power the same 18 x 6 propeller.
The concern was how to make either system easy to install.
The solution was to construct the firewall from three laminations;
the first two are light plywood and the third is aircraft-grade
plywood. One light-plywood firewall is precut for the G-26 gas
engine and the other is precut for the AXI 4130/20 motor. The
builder arranges the three layers so that the chosen power system
is on top (the first layer).
The G-26 firewall is designed to accept the stock mount and
muffler, which saves the modeler from having to purchase
additional accessories. The G-26 firewall has laser cutouts for the
fuel line, vent line, and throttle pushrod. The engine installation
merely requires four blind nuts.
The completed SR Eindecker E.I is ready for flight. Field setup
has been reduced to only a few minutes. The Eindecker E.I in flight, searching for the enemy.
Big is Better and Safer too!
The IMAA is an international organization was formed April 10,
1980 to promote non-competitive, educational, safe, relaxed flying
of LARGE radio controlled model aircraft throughout the world.
We are the largest Academy of Model Aeronautics (AMA) Special
Interest Group and as such, are committed to representing the
interest of our members in AMA related matters.
Members enjoy the privilege of
participation in hundreds of Fly-ins
and Rallies each year – including
IMAA’s own Rally of Giants).
Don’t wait. Join today! For complete
membership details, visit our web site
(www.fly-imaa.org) or give us a call
toll free at – 866 366-4622.
High-Flight,
the publication of the IMAA, is
published quarterly and is sent to
all members. High-Flight is
dedicated to the advancement of
large r/c aircraft by concentrating
on new products, techniques, and
innovations developed through
the activities of IMAA Chapters
and individuals around the world.
09sig4.QXD 6/23/04 12:54 pm Page 100
September 2004 101
Wing Assembly: Having built and sanded
many Giant Scale wings, I found it timeconsuming
and difficult to make round and
true LEs. In addition, with the natural
tendency of wood spars to warp, sometimes
it is hard to build a straight wing.
The solution was to incorporate the wing
designs from the SR X250 and Cutie into
the Eindecker wing. This involved using
three 1⁄2-inch composite tubes in each wing
panel. Two are used as spars while the third
tube is used as the LE. The result is a superstrong,
straight panel that requires no
sanding of the LE.
We designed light-plywood combs that
are used during wing construction to align
and space out the ribs. After the first few
ribs are glued in place, you simply pick up
the combs and move them farther along the
wing. The result is that the wing panels
build quickly and accurately.
The aileron servos are installed on a
laser-cut servo-mount assembly. These are
nothing new, but all of them that I have seen
have the actual servo-mount butt glued to
the servo wing cover. I have seen these glue
joints separate during hard landings when an
excessive load is placed on the servo. We
went through the extra effort of having the
mount pieces keyed into the wing cover.
Fuselage: The standard stick-built fuselage
of World War I vintage has always posed
concerns, especially when joining the rear
part of the fuselage. I can’t tell you how
many “bananas” I have built. We wanted a
design that eliminated the banana problem.
We came up with laser-cut notched parts
which include the firewall, forward fuselage
sides, doublers, formers, and laser-cut servo
tray that ensure proper alignment of the
forward part of the fuselage. Our
construction method is to build one side
over the plans and then build the second
side over the first side. In this manner, the
sides are duplicates.
Empennage: In model aircraft this size, the
horizontal stabilizer is usually supported by
braces or wires. Since the Eindecker did not
have these, we needed to construct a stabilizer
that would not use support braces. As with the
wing, the solution was to use a composite
tube for the LE of the stabilizer. The tube
allows the stabilizer to flex but not break.
The elevators have the same-size
composite tubes used in the TE. All of these
tubes provide another benefit; they make
these parts ding-proof.
The remaining outlines of the stabilizer
and elevators are constructed from light
plywood and balsa laminations to make
them stronger.
The rudder is a full flying rudder. There
is no hinging on it. We were able to
incorporate a tube-in-a-tube assembly in
which the rudder rotates. The outer tube is
part of the tail-skid assembly which is
mounted directly to the fuselage.
Landing Gear: In larger RC models,
shock-absorbing landing gear is a must. The
Eindecker gear is not easy to replicate
because of its complexity and multifunction.
On the full-scale aircraft, it was designed to
accommodate wing warping and flying
wires, and absorb shock on landing.
The model was not designed for wingwarping
operation, but we still needed to
support the flying wires in the same fashion
as the full-scale Eindecker. To create a gear
that looked right, would support the flying
wires, and would provide shock-absorbing
capability, we built and tested a few designs
before we found a solution that worked
superbly. The finished product looks like an
Eindecker gear and is installed with just
four nylon straps.
The tail skid was also designed to be
shock absorbing and uses the same type of
composite tube that is in the wings and tail
feathers.
Field Setup: There are no screws or bolts
that attach the wing panels to the fuselage.
The wings are held in place by the flying
and landing wires. The full-scale
Eindecker had many of them and the
model doesn’t look right without them.
We had seen models that used clevises
and threaded couplers to secure the flying
wires. We were not satisfied with this type
of installation because it took too long to
set up at the field, and inevitably one or
more wires would come loose during
flight.
We first tested a prototype that required
six attachment points: two for the upper
cabanes and four for the flying wires on
the landing gear. Eventually we were able
to reduce this number to only four
attachment points: two above and two
below. Field setup has now been reduced
to only a few minutes.
The Eindecker represents nine months
and hundreds of hours of hard work. It was
certainly an eye-opener for me, and I am
happy that I had the opportunity to be
involved in the process. I know that it has
made me a better modeler.
I hope you’ll agree that we were able to
solve some common problems associated
with model building and that our hard
work resulted in a fast, fun-building, and
great-flying World War I RC Giant.
For color photos and flying videos, you
can visit the SR Batteries Web site at
www.srbatteries.com or call (631) 286-
0079.
See you next month. MA
09sig4.QXD 6/23/04 12:54 pm Page 101
Edition: Model Aviation - 2004/09
Page Numbers: 98,100,101
98 MODEL AVIATION
I’M SO EXCITED about our latest project that I want to share it
with you. I have been infatuated with RC Giants for approximately
20 years. In that time I have built models from kits and plans, I
scratch-built from three-views, and even put together a couple of
Giant ARFs. Imagine my joy when I actually became involved with
designing a Giant Scale model for manufacture.
During the past nine months I have been working with Larry
Sribnick, the president of SR Batteries, designing a 1⁄4-scale Fokker
Eindecker E.I. Larry is well known for his outstanding designs such
as the X250, Cutie, and AcroPro model kits. We were able to take
some of the innovative design features of these smaller models
along with the experience I have with gas-powered models and
apply it to a 100-inch-wingspan, 16-pound World War I fighter.
One of the first lessons that I had to learn was patience. It may
have only taken a couple of months to construct a one-off aircraft
for myself, but designing and building a model as a product for
others to build is quite a different task. Plans needed to be drawn,
exact-fitting balsa and light-plywood parts had to be made, and an
easy-to-follow, descriptive instruction manual had to be written.
In addition, a landing gear, a tail-skid assembly, and a cabane
assembly had to be designed, built, and tested, and an appropriate
aluminum cowling needed to be manufactured. All of this required
hundreds of hours of computer-aided design (CAD) work and
prototype development.
There were times when Larry and I agreed on certain aspects or
ideas and other times when we disagreed. In the end, all of our
discussions made for a much better finished product. We are both
proud of the outcome, although I still have problems with being
patient. Perhaps yoga would help.
It has been my experience that during construction of any model
kit, I would come to a particular step where I would say to myself,
“Why did they do it this way?” or “I could have designed this
better.” With the Eindecker, here was my opportunity. The next few
paragraphs detail some of the issues that we’ve seen as a problem or
concern and how we addressed these issues in the Eindecker.
One of the first decisions made was that the model should be
quick and easy to build and fun for anyone to fly. The Fokker
Eindecker E.I was the premier fighter early in World War I. Unlike
many of its contemporaries, it had only one wing to contend with
and a boxy fuselage. These attributes made building the kit
attractive.
Sal Calvagna, 1335 Broadway Ave., Holbrook NY 11741; E-mail: [email protected]
RADIO CONTROL GIANTS
The Aces of Iron Productions, Inc. pilot comes unpainted, and
the landing wire attachment points can be clearly seen.
The balsa cheek assemblies are constructed separately from the
fuselage in the author and Larry Sribnick’s Eindecker E.I.
The wing panel showing the composite spars and LE. The comb
is used for alignment and spacing during construction.
This shows the three firewall laminations. Two have laser cutouts
to accommodate an engine or a motor.
09sig4.QXD 6/23/04 12:54 pm Page 98
100 MODEL AVIATION
The full-scale Eindecker used wing warping and full flying
stabilizer and rudder. We used a more traditional approach and
incorporated ailerons and elevators; however, we kept the full
flying rudder. At 100 inches, the model can be entered in any of
the International Miniature Aircraft Association events including
the popular warbird categories.
Manufacturing Process: To maintain exact tolerances, we
believed the best method of design and manufacture was CAD and
micro laser-cutting. This type of process could ensure accurately
fitting parts. This became critical with the composite spar and LE
design chosen for the Eindecker wings.
Power System: Usually a model is designed with electric, gas, or
glow as the power plant of choice. We decided early in the
process that the model would be dual-powered for gas or glow
(wet) or electric (dry). We specifically designed the kit to
accommodate both systems. We chose the Zenoah G-26 for the
gas-powered version and the AXI 4130/20 brushless motor for the
electric power system. Both power the same 18 x 6 propeller.
The concern was how to make either system easy to install.
The solution was to construct the firewall from three laminations;
the first two are light plywood and the third is aircraft-grade
plywood. One light-plywood firewall is precut for the G-26 gas
engine and the other is precut for the AXI 4130/20 motor. The
builder arranges the three layers so that the chosen power system
is on top (the first layer).
The G-26 firewall is designed to accept the stock mount and
muffler, which saves the modeler from having to purchase
additional accessories. The G-26 firewall has laser cutouts for the
fuel line, vent line, and throttle pushrod. The engine installation
merely requires four blind nuts.
The completed SR Eindecker E.I is ready for flight. Field setup
has been reduced to only a few minutes. The Eindecker E.I in flight, searching for the enemy.
Big is Better and Safer too!
The IMAA is an international organization was formed April 10,
1980 to promote non-competitive, educational, safe, relaxed flying
of LARGE radio controlled model aircraft throughout the world.
We are the largest Academy of Model Aeronautics (AMA) Special
Interest Group and as such, are committed to representing the
interest of our members in AMA related matters.
Members enjoy the privilege of
participation in hundreds of Fly-ins
and Rallies each year – including
IMAA’s own Rally of Giants).
Don’t wait. Join today! For complete
membership details, visit our web site
(www.fly-imaa.org) or give us a call
toll free at – 866 366-4622.
High-Flight,
the publication of the IMAA, is
published quarterly and is sent to
all members. High-Flight is
dedicated to the advancement of
large r/c aircraft by concentrating
on new products, techniques, and
innovations developed through
the activities of IMAA Chapters
and individuals around the world.
09sig4.QXD 6/23/04 12:54 pm Page 100
September 2004 101
Wing Assembly: Having built and sanded
many Giant Scale wings, I found it timeconsuming
and difficult to make round and
true LEs. In addition, with the natural
tendency of wood spars to warp, sometimes
it is hard to build a straight wing.
The solution was to incorporate the wing
designs from the SR X250 and Cutie into
the Eindecker wing. This involved using
three 1⁄2-inch composite tubes in each wing
panel. Two are used as spars while the third
tube is used as the LE. The result is a superstrong,
straight panel that requires no
sanding of the LE.
We designed light-plywood combs that
are used during wing construction to align
and space out the ribs. After the first few
ribs are glued in place, you simply pick up
the combs and move them farther along the
wing. The result is that the wing panels
build quickly and accurately.
The aileron servos are installed on a
laser-cut servo-mount assembly. These are
nothing new, but all of them that I have seen
have the actual servo-mount butt glued to
the servo wing cover. I have seen these glue
joints separate during hard landings when an
excessive load is placed on the servo. We
went through the extra effort of having the
mount pieces keyed into the wing cover.
Fuselage: The standard stick-built fuselage
of World War I vintage has always posed
concerns, especially when joining the rear
part of the fuselage. I can’t tell you how
many “bananas” I have built. We wanted a
design that eliminated the banana problem.
We came up with laser-cut notched parts
which include the firewall, forward fuselage
sides, doublers, formers, and laser-cut servo
tray that ensure proper alignment of the
forward part of the fuselage. Our
construction method is to build one side
over the plans and then build the second
side over the first side. In this manner, the
sides are duplicates.
Empennage: In model aircraft this size, the
horizontal stabilizer is usually supported by
braces or wires. Since the Eindecker did not
have these, we needed to construct a stabilizer
that would not use support braces. As with the
wing, the solution was to use a composite
tube for the LE of the stabilizer. The tube
allows the stabilizer to flex but not break.
The elevators have the same-size
composite tubes used in the TE. All of these
tubes provide another benefit; they make
these parts ding-proof.
The remaining outlines of the stabilizer
and elevators are constructed from light
plywood and balsa laminations to make
them stronger.
The rudder is a full flying rudder. There
is no hinging on it. We were able to
incorporate a tube-in-a-tube assembly in
which the rudder rotates. The outer tube is
part of the tail-skid assembly which is
mounted directly to the fuselage.
Landing Gear: In larger RC models,
shock-absorbing landing gear is a must. The
Eindecker gear is not easy to replicate
because of its complexity and multifunction.
On the full-scale aircraft, it was designed to
accommodate wing warping and flying
wires, and absorb shock on landing.
The model was not designed for wingwarping
operation, but we still needed to
support the flying wires in the same fashion
as the full-scale Eindecker. To create a gear
that looked right, would support the flying
wires, and would provide shock-absorbing
capability, we built and tested a few designs
before we found a solution that worked
superbly. The finished product looks like an
Eindecker gear and is installed with just
four nylon straps.
The tail skid was also designed to be
shock absorbing and uses the same type of
composite tube that is in the wings and tail
feathers.
Field Setup: There are no screws or bolts
that attach the wing panels to the fuselage.
The wings are held in place by the flying
and landing wires. The full-scale
Eindecker had many of them and the
model doesn’t look right without them.
We had seen models that used clevises
and threaded couplers to secure the flying
wires. We were not satisfied with this type
of installation because it took too long to
set up at the field, and inevitably one or
more wires would come loose during
flight.
We first tested a prototype that required
six attachment points: two for the upper
cabanes and four for the flying wires on
the landing gear. Eventually we were able
to reduce this number to only four
attachment points: two above and two
below. Field setup has now been reduced
to only a few minutes.
The Eindecker represents nine months
and hundreds of hours of hard work. It was
certainly an eye-opener for me, and I am
happy that I had the opportunity to be
involved in the process. I know that it has
made me a better modeler.
I hope you’ll agree that we were able to
solve some common problems associated
with model building and that our hard
work resulted in a fast, fun-building, and
great-flying World War I RC Giant.
For color photos and flying videos, you
can visit the SR Batteries Web site at
www.srbatteries.com or call (631) 286-
0079.
See you next month. MA
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