July 2004 19
THE IDEA FOR this model was derived
from an airplane that Igo Etrich designed in
1912. His inspiration came not from a bird
but from a palm tree. Its seeds were winged,
and as he watched them fall, he felt sure that
they had an aerodynamic design he could use
for an airplane. Etrich’s aircraft looked
more like a bird than a flying seed; hence its
name—the “Taube”—meaning dove. In
flight, the graceful outline justified the name,
but a closer look revealed that the machine
was covered with wires. Etrich gave up his
claim to the design’s copyright, and the
airplane proved to be the father of many
future airplanes, including ITSA BIRD.
CONSTRUCTION
This model’s construction is basic;
however, the materials’ weight is critical to
obtain maximum performance. Therefore,
you should make every effort to use 4- to 6-
pound, lightweight balsa stock for sheet and
for sticks.
Wing: Before commencing construction,
photocopy the wing ribs section and cover the
plans with waxed paper or plastic film. Use a
light coat of rubber cement or 3M Super 77
Spray Adhesive to tack the outlines onto 1⁄16
sheet balsa. For ribs WR1 and WR3, it is
helpful to cut templates from 1⁄16 plywood.
Since most ribs require a bit of trimming
for a proper fit, lengthen each approximately
1⁄4 inch when cutting them out. After cutting
out all the ribs, stack and sand them so that
little or no sanding will be needed after the
framework is finished.
You construct the LEs and TEs by
laminating three strips of 1⁄16 x 1⁄4 balsa. To
increase their flexibility, soak them in warm
water or a 50/50 solution of ammonia and
water. Use a slightly watered-down mixture
of Elmer’s Carpenter’s Wood Glue or
Franklin Titebond wood glue to laminate.
After you have pinned and glued the
entire LE and TE, cut both edges at the
dihedral breaks to produce 30° angles. Cut
Author with
his model,
ready for
indoor flight.
Idea for wing
shape
originally
came from a
palm-tree
seed in
1912!
by Larry Katz
07sig1.QXD 4/26/04 10:01 am Page 19
and glue each rib in place. Omit the double ribs WR3 until the
dihedral is set. Leave the center-section pinned to the plans, and
raise each wingtip 41⁄2 inches and glue in place. At this time you
can install ribs WR3 and all wing gussets.
Before removing the structure from the plans, install the 1⁄16-
inch square spar and sheet the center-section (top only). When the
wing is dry, remove it from the plans and round it by trimming,
shaping, and sanding the entire LE and TE. Set aside for
covering.
Tail Feathers: Elevator and rudder construction are basic. Either
3⁄32 or 1⁄8 square balsa will produce structures with little or no
weight difference, as long as it is lightweight. The plans indicate
the use of Sig Easy Hinges, but any comparable hinge is
satisfactory.
I used thin sheet aluminum to form rudder and elevator horns.
A good source for this material is the top of certain packaged
products. I obtained my aluminum from a can of French’s French
Fried Onions. You can also make horns from 1⁄32 plywood. Before
you install the horns, sand the rudder and elevator.
Fuselage: Before you begin fuselage construction, cut the motormount
nosepiece from 1⁄16 plywood and cut a hole large enough to
accept whatever motor you intend to use. I also advise you to
construct the landing-gear assembly at this time. This step
requires you to cut formers F1, F2, F3, and two lengths of 1.5mm
carbon rod. Exercise caution when cutting carbon; it is best to
place masking tape at the point of cut, and use a Dremel or
similar tool.
Cut and bend 0.1mm piano wire for the wheel axles, tie it to
the rods with buttonhole thread, and glue it in place. For a neater
application you can cover this section with 1⁄16-inch heat-shrink
tubing, but it is not necessary.
I chose 17⁄8-inch-diameter GWS wheels. They will operate
better and with less friction if you insert 1⁄4-inch lengths of 1⁄16-
inch aluminum or brass tubing into each hub.
Epoxy the carbon landing gears into a sandwich created by
formers F1, F2, and F3. Make sure that both are aligned correctly.
When they are dry, slip the GWS wheels on the axles and use a
small bead of epoxy to hold them in place.
Trace two fuselage-side outlines on lightweight 1⁄16 sheet
balsa. On each side, mark the location of all 1⁄16-inch square
verticals, the motor-mount nosepiece, and the wing hold-down
supports. Now you are ready to join the fuselage sides. Make sure
to incorporate 5° of negative incidence when installing and gluing
the nosepiece.
Cut the equipment tray from 1⁄16-inch sheet balsa, and double
the servo location with cross-grained balsa. The balsa equipment
tray rests on the rear portion of the landing-gear assembly.
Glue in place, and measure and cut all 1⁄16-inch fuselage
crossbraces. Since the portion of the fuselage under the wing
must fit between the wing’s center-section, test-fit before
you glue those crossbraces. The crossbraces under the
wing must be at least 3⁄8 inch below the fuselage top to
provide sufficient clearance. When crossbracing is
complete, attach Velcro strips in place to hold down
the speed controller, receiver, and battery.
Do not install 1⁄16 sheet balsa (cross-grained) on the
top and bottom of the fuselage nose area until the motor
and speed controller have been installed. Finally, bend
and install the piano-wire tail skid, and carefully sand the
fuselage.
Before setting it aside for later installation of the motor and
radio equipment, test-fit the wing onto the fuselage. It will
require a 1⁄8 x 3⁄16-inch notch just behind the LE at the bottom of
the center double rib to permit clearance over the landing-gear
bulkhead.
Equipment Installation: The light flyer aspect of this hobby has
20 MODEL AVIATION
The author recommends that you employ either Litespan or GM
Tissue as covering materials. They are both light and strong.
Type: Indoor electric sport
Wingspan: 45 inches
Power: GWS A or geared DC 1717 motor
Flying weight: 6-8 ounces
Construction: Built-up balsa
Covering/finish: Litespan or GM Tissue
07sig1.QXD 4/26/04 10:02 am Page 20
become so popular that there is a wide range of appropriate
electric motors available. In my first test model I used a DC
1717, which was geared and weighed 21 grams, but it seemed to
lack sufficient thrust using a 9.4 x 7 carbon propeller.
During the time I was testing ITSA BIRD, GWS came out
with a new series of small but extremely efficient motors. I
installed a GWS A and used the GWS 10 x 4.7 plastic propeller.
This motor has an external 5.86:1 gear ratio and provides more
than ample thrust. Using the GWS motor required modification
of the nose section, as illustrated on the plans, and a change to 3°
of negative incidence.
I also replaced a seven-cell 50 mAh Ni-Cd battery pack with
an eight-cell 280 mAh NiMH battery pack stacked four over four.
It weighs the same and provides twice the flying time.
Depending on whether you use a push-pull or a pull-pull
system of controlling tail surfaces, you may have to install balsa
exit guides in the fuselage and elevator. I chose to use 1.5mm
(0.06-inch) carbon pushrods that were stiff enough to negate the
use of interior fuselage guides.
I chose to use the Hitec HAS-3MB
super-narrow-band three-channel receiver
on 27 MHz and removed the top cover to
save weight. Two Hitec HS-50 servos
worked perfectly. I tested an Alpex-4FM
microreceiver (72 MHz), and it worked
well. I selected a Castle Creations Pixie-14
speed controller, but there are many
comparable units on the market.
I attached the battery, receiver, and
speed controller using Velcro. I
incorporated 1⁄2-inch deflection in the
elevator and 3⁄4-inch deflection in the
rudder to permit tight turns.
Covering: Since weight is critical, use a
lightweight covering such as Litespan or
GM (Gas Model) Tissue; both are heatshrinkable
but require that you apply
Balsarite or Sig Stix-It to the framework.
Cover only the top of the wing and
elevator. Cover the rudder on both sides.
Be extremely careful when applying heat
to prevent warping.
Once the elevator and rudder are
covered, install the hinges and horns. Do
not cover the fuselage section under the
wing or where the radio-equipment
compartment is located. Glue the rudder
and elevator to the fuselage.
Flying: Attach the wing using thin rubber
bands. I found that two No. 18 bands tied
together and crisscrossed over the wing
work well. Before flying, make sure the
balance is correct. If adjustment is needed,
using Velcro permits the battery to be
moved accordingly.
After I checked the balance and the
motor and radio equipment were
functioning properly, I made the first test
flight. ITSA BIRD broke ground after a
roll of 10-15 feet. Once level flight was
obtained and I attempted left and right
turns, half throttle was more than
sufficient and a smooth, tight Figure Eight
was easily attainable. You should make
every effort to prevent dead-stick landings,
so be sure to retain power until
touchdown.
Subsequent flights lasted longer than 12 minutes using the
NiMH batteries. If you fly outdoors, try to select a wind-free day
and stay away from moving trees. MA
Larry Katz
1658 Buttonwood Ave.
Toms River NJ 08755
July 2004 21
ITSA BIRD is at home below the beams in any large indoor flying site. It can also be
flown outdoors on calm days. It will turn heads wherever you fly it!
Servo, receiver, and battery access is accomplished through an opening in the bottom
of the aircraft’s fuselage. This installation is practical and simple.
Sources:
Balsa Products
122 Jansen Ave.
Iselin NJ 08830
David Lewis
4027 Rocky River 26
Cleveland OH 44135
Hitec, RCD, Inc.
12115 Paine St.
Poway CA 92064
Castle Creations
402 E. Pendleton Ave.
Wellsville KS 66092
K&S Engineering
6917 W. 59 St.
Chicago IL 60638
Don Post Batteries
1772 Buttonwood Ave.
Toms River NJ 08755
07sig1.QXD 4/26/04 10:03 am Page 21
22 MODEL AVIATION
The stabilizer and elevator are built from balsa strip stock over
the plans as shown. They’re light but sturdy!
The fin and rudder are shown assembled. Notice that the tail
feathers combine to augment the birdlike look.
Unusual? You bet, and that’s hard to achieve these days! Note
extra-long landing gear for good propeller clearance.
The wing has plenty of area, and at the 6- to 8-ounce flying
weight, ITSA BIRD will yield great slow-flight characteristics.
The two fuselage sides are ready for construction. The landing
gear is lashed to a former before assembly.
The laminated LEs and TEs are pinned over the wing outline on
the plans as shown. It takes a great deal of pins!
Stack-sanded ribs have been cut and fit to the framework. The outer-section dihedral has been added and the spar has
been installed. You know, it does look like a bird!
Photos courtesy the author
07sig1.QXD 4/26/04 10:04 am Page 22
Edition: Model Aviation - 2004/07
Page Numbers: 19,20,21,22,23
Edition: Model Aviation - 2004/07
Page Numbers: 19,20,21,22,23
July 2004 19
THE IDEA FOR this model was derived
from an airplane that Igo Etrich designed in
1912. His inspiration came not from a bird
but from a palm tree. Its seeds were winged,
and as he watched them fall, he felt sure that
they had an aerodynamic design he could use
for an airplane. Etrich’s aircraft looked
more like a bird than a flying seed; hence its
name—the “Taube”—meaning dove. In
flight, the graceful outline justified the name,
but a closer look revealed that the machine
was covered with wires. Etrich gave up his
claim to the design’s copyright, and the
airplane proved to be the father of many
future airplanes, including ITSA BIRD.
CONSTRUCTION
This model’s construction is basic;
however, the materials’ weight is critical to
obtain maximum performance. Therefore,
you should make every effort to use 4- to 6-
pound, lightweight balsa stock for sheet and
for sticks.
Wing: Before commencing construction,
photocopy the wing ribs section and cover the
plans with waxed paper or plastic film. Use a
light coat of rubber cement or 3M Super 77
Spray Adhesive to tack the outlines onto 1⁄16
sheet balsa. For ribs WR1 and WR3, it is
helpful to cut templates from 1⁄16 plywood.
Since most ribs require a bit of trimming
for a proper fit, lengthen each approximately
1⁄4 inch when cutting them out. After cutting
out all the ribs, stack and sand them so that
little or no sanding will be needed after the
framework is finished.
You construct the LEs and TEs by
laminating three strips of 1⁄16 x 1⁄4 balsa. To
increase their flexibility, soak them in warm
water or a 50/50 solution of ammonia and
water. Use a slightly watered-down mixture
of Elmer’s Carpenter’s Wood Glue or
Franklin Titebond wood glue to laminate.
After you have pinned and glued the
entire LE and TE, cut both edges at the
dihedral breaks to produce 30° angles. Cut
Author with
his model,
ready for
indoor flight.
Idea for wing
shape
originally
came from a
palm-tree
seed in
1912!
by Larry Katz
07sig1.QXD 4/26/04 10:01 am Page 19
and glue each rib in place. Omit the double ribs WR3 until the
dihedral is set. Leave the center-section pinned to the plans, and
raise each wingtip 41⁄2 inches and glue in place. At this time you
can install ribs WR3 and all wing gussets.
Before removing the structure from the plans, install the 1⁄16-
inch square spar and sheet the center-section (top only). When the
wing is dry, remove it from the plans and round it by trimming,
shaping, and sanding the entire LE and TE. Set aside for
covering.
Tail Feathers: Elevator and rudder construction are basic. Either
3⁄32 or 1⁄8 square balsa will produce structures with little or no
weight difference, as long as it is lightweight. The plans indicate
the use of Sig Easy Hinges, but any comparable hinge is
satisfactory.
I used thin sheet aluminum to form rudder and elevator horns.
A good source for this material is the top of certain packaged
products. I obtained my aluminum from a can of French’s French
Fried Onions. You can also make horns from 1⁄32 plywood. Before
you install the horns, sand the rudder and elevator.
Fuselage: Before you begin fuselage construction, cut the motormount
nosepiece from 1⁄16 plywood and cut a hole large enough to
accept whatever motor you intend to use. I also advise you to
construct the landing-gear assembly at this time. This step
requires you to cut formers F1, F2, F3, and two lengths of 1.5mm
carbon rod. Exercise caution when cutting carbon; it is best to
place masking tape at the point of cut, and use a Dremel or
similar tool.
Cut and bend 0.1mm piano wire for the wheel axles, tie it to
the rods with buttonhole thread, and glue it in place. For a neater
application you can cover this section with 1⁄16-inch heat-shrink
tubing, but it is not necessary.
I chose 17⁄8-inch-diameter GWS wheels. They will operate
better and with less friction if you insert 1⁄4-inch lengths of 1⁄16-
inch aluminum or brass tubing into each hub.
Epoxy the carbon landing gears into a sandwich created by
formers F1, F2, and F3. Make sure that both are aligned correctly.
When they are dry, slip the GWS wheels on the axles and use a
small bead of epoxy to hold them in place.
Trace two fuselage-side outlines on lightweight 1⁄16 sheet
balsa. On each side, mark the location of all 1⁄16-inch square
verticals, the motor-mount nosepiece, and the wing hold-down
supports. Now you are ready to join the fuselage sides. Make sure
to incorporate 5° of negative incidence when installing and gluing
the nosepiece.
Cut the equipment tray from 1⁄16-inch sheet balsa, and double
the servo location with cross-grained balsa. The balsa equipment
tray rests on the rear portion of the landing-gear assembly.
Glue in place, and measure and cut all 1⁄16-inch fuselage
crossbraces. Since the portion of the fuselage under the wing
must fit between the wing’s center-section, test-fit before
you glue those crossbraces. The crossbraces under the
wing must be at least 3⁄8 inch below the fuselage top to
provide sufficient clearance. When crossbracing is
complete, attach Velcro strips in place to hold down
the speed controller, receiver, and battery.
Do not install 1⁄16 sheet balsa (cross-grained) on the
top and bottom of the fuselage nose area until the motor
and speed controller have been installed. Finally, bend
and install the piano-wire tail skid, and carefully sand the
fuselage.
Before setting it aside for later installation of the motor and
radio equipment, test-fit the wing onto the fuselage. It will
require a 1⁄8 x 3⁄16-inch notch just behind the LE at the bottom of
the center double rib to permit clearance over the landing-gear
bulkhead.
Equipment Installation: The light flyer aspect of this hobby has
20 MODEL AVIATION
The author recommends that you employ either Litespan or GM
Tissue as covering materials. They are both light and strong.
Type: Indoor electric sport
Wingspan: 45 inches
Power: GWS A or geared DC 1717 motor
Flying weight: 6-8 ounces
Construction: Built-up balsa
Covering/finish: Litespan or GM Tissue
07sig1.QXD 4/26/04 10:02 am Page 20
become so popular that there is a wide range of appropriate
electric motors available. In my first test model I used a DC
1717, which was geared and weighed 21 grams, but it seemed to
lack sufficient thrust using a 9.4 x 7 carbon propeller.
During the time I was testing ITSA BIRD, GWS came out
with a new series of small but extremely efficient motors. I
installed a GWS A and used the GWS 10 x 4.7 plastic propeller.
This motor has an external 5.86:1 gear ratio and provides more
than ample thrust. Using the GWS motor required modification
of the nose section, as illustrated on the plans, and a change to 3°
of negative incidence.
I also replaced a seven-cell 50 mAh Ni-Cd battery pack with
an eight-cell 280 mAh NiMH battery pack stacked four over four.
It weighs the same and provides twice the flying time.
Depending on whether you use a push-pull or a pull-pull
system of controlling tail surfaces, you may have to install balsa
exit guides in the fuselage and elevator. I chose to use 1.5mm
(0.06-inch) carbon pushrods that were stiff enough to negate the
use of interior fuselage guides.
I chose to use the Hitec HAS-3MB
super-narrow-band three-channel receiver
on 27 MHz and removed the top cover to
save weight. Two Hitec HS-50 servos
worked perfectly. I tested an Alpex-4FM
microreceiver (72 MHz), and it worked
well. I selected a Castle Creations Pixie-14
speed controller, but there are many
comparable units on the market.
I attached the battery, receiver, and
speed controller using Velcro. I
incorporated 1⁄2-inch deflection in the
elevator and 3⁄4-inch deflection in the
rudder to permit tight turns.
Covering: Since weight is critical, use a
lightweight covering such as Litespan or
GM (Gas Model) Tissue; both are heatshrinkable
but require that you apply
Balsarite or Sig Stix-It to the framework.
Cover only the top of the wing and
elevator. Cover the rudder on both sides.
Be extremely careful when applying heat
to prevent warping.
Once the elevator and rudder are
covered, install the hinges and horns. Do
not cover the fuselage section under the
wing or where the radio-equipment
compartment is located. Glue the rudder
and elevator to the fuselage.
Flying: Attach the wing using thin rubber
bands. I found that two No. 18 bands tied
together and crisscrossed over the wing
work well. Before flying, make sure the
balance is correct. If adjustment is needed,
using Velcro permits the battery to be
moved accordingly.
After I checked the balance and the
motor and radio equipment were
functioning properly, I made the first test
flight. ITSA BIRD broke ground after a
roll of 10-15 feet. Once level flight was
obtained and I attempted left and right
turns, half throttle was more than
sufficient and a smooth, tight Figure Eight
was easily attainable. You should make
every effort to prevent dead-stick landings,
so be sure to retain power until
touchdown.
Subsequent flights lasted longer than 12 minutes using the
NiMH batteries. If you fly outdoors, try to select a wind-free day
and stay away from moving trees. MA
Larry Katz
1658 Buttonwood Ave.
Toms River NJ 08755
July 2004 21
ITSA BIRD is at home below the beams in any large indoor flying site. It can also be
flown outdoors on calm days. It will turn heads wherever you fly it!
Servo, receiver, and battery access is accomplished through an opening in the bottom
of the aircraft’s fuselage. This installation is practical and simple.
Sources:
Balsa Products
122 Jansen Ave.
Iselin NJ 08830
David Lewis
4027 Rocky River 26
Cleveland OH 44135
Hitec, RCD, Inc.
12115 Paine St.
Poway CA 92064
Castle Creations
402 E. Pendleton Ave.
Wellsville KS 66092
K&S Engineering
6917 W. 59 St.
Chicago IL 60638
Don Post Batteries
1772 Buttonwood Ave.
Toms River NJ 08755
07sig1.QXD 4/26/04 10:03 am Page 21
22 MODEL AVIATION
The stabilizer and elevator are built from balsa strip stock over
the plans as shown. They’re light but sturdy!
The fin and rudder are shown assembled. Notice that the tail
feathers combine to augment the birdlike look.
Unusual? You bet, and that’s hard to achieve these days! Note
extra-long landing gear for good propeller clearance.
The wing has plenty of area, and at the 6- to 8-ounce flying
weight, ITSA BIRD will yield great slow-flight characteristics.
The two fuselage sides are ready for construction. The landing
gear is lashed to a former before assembly.
The laminated LEs and TEs are pinned over the wing outline on
the plans as shown. It takes a great deal of pins!
Stack-sanded ribs have been cut and fit to the framework. The outer-section dihedral has been added and the spar has
been installed. You know, it does look like a bird!
Photos courtesy the author
07sig1.QXD 4/26/04 10:04 am Page 22
Edition: Model Aviation - 2004/07
Page Numbers: 19,20,21,22,23
July 2004 19
THE IDEA FOR this model was derived
from an airplane that Igo Etrich designed in
1912. His inspiration came not from a bird
but from a palm tree. Its seeds were winged,
and as he watched them fall, he felt sure that
they had an aerodynamic design he could use
for an airplane. Etrich’s aircraft looked
more like a bird than a flying seed; hence its
name—the “Taube”—meaning dove. In
flight, the graceful outline justified the name,
but a closer look revealed that the machine
was covered with wires. Etrich gave up his
claim to the design’s copyright, and the
airplane proved to be the father of many
future airplanes, including ITSA BIRD.
CONSTRUCTION
This model’s construction is basic;
however, the materials’ weight is critical to
obtain maximum performance. Therefore,
you should make every effort to use 4- to 6-
pound, lightweight balsa stock for sheet and
for sticks.
Wing: Before commencing construction,
photocopy the wing ribs section and cover the
plans with waxed paper or plastic film. Use a
light coat of rubber cement or 3M Super 77
Spray Adhesive to tack the outlines onto 1⁄16
sheet balsa. For ribs WR1 and WR3, it is
helpful to cut templates from 1⁄16 plywood.
Since most ribs require a bit of trimming
for a proper fit, lengthen each approximately
1⁄4 inch when cutting them out. After cutting
out all the ribs, stack and sand them so that
little or no sanding will be needed after the
framework is finished.
You construct the LEs and TEs by
laminating three strips of 1⁄16 x 1⁄4 balsa. To
increase their flexibility, soak them in warm
water or a 50/50 solution of ammonia and
water. Use a slightly watered-down mixture
of Elmer’s Carpenter’s Wood Glue or
Franklin Titebond wood glue to laminate.
After you have pinned and glued the
entire LE and TE, cut both edges at the
dihedral breaks to produce 30° angles. Cut
Author with
his model,
ready for
indoor flight.
Idea for wing
shape
originally
came from a
palm-tree
seed in
1912!
by Larry Katz
07sig1.QXD 4/26/04 10:01 am Page 19
and glue each rib in place. Omit the double ribs WR3 until the
dihedral is set. Leave the center-section pinned to the plans, and
raise each wingtip 41⁄2 inches and glue in place. At this time you
can install ribs WR3 and all wing gussets.
Before removing the structure from the plans, install the 1⁄16-
inch square spar and sheet the center-section (top only). When the
wing is dry, remove it from the plans and round it by trimming,
shaping, and sanding the entire LE and TE. Set aside for
covering.
Tail Feathers: Elevator and rudder construction are basic. Either
3⁄32 or 1⁄8 square balsa will produce structures with little or no
weight difference, as long as it is lightweight. The plans indicate
the use of Sig Easy Hinges, but any comparable hinge is
satisfactory.
I used thin sheet aluminum to form rudder and elevator horns.
A good source for this material is the top of certain packaged
products. I obtained my aluminum from a can of French’s French
Fried Onions. You can also make horns from 1⁄32 plywood. Before
you install the horns, sand the rudder and elevator.
Fuselage: Before you begin fuselage construction, cut the motormount
nosepiece from 1⁄16 plywood and cut a hole large enough to
accept whatever motor you intend to use. I also advise you to
construct the landing-gear assembly at this time. This step
requires you to cut formers F1, F2, F3, and two lengths of 1.5mm
carbon rod. Exercise caution when cutting carbon; it is best to
place masking tape at the point of cut, and use a Dremel or
similar tool.
Cut and bend 0.1mm piano wire for the wheel axles, tie it to
the rods with buttonhole thread, and glue it in place. For a neater
application you can cover this section with 1⁄16-inch heat-shrink
tubing, but it is not necessary.
I chose 17⁄8-inch-diameter GWS wheels. They will operate
better and with less friction if you insert 1⁄4-inch lengths of 1⁄16-
inch aluminum or brass tubing into each hub.
Epoxy the carbon landing gears into a sandwich created by
formers F1, F2, and F3. Make sure that both are aligned correctly.
When they are dry, slip the GWS wheels on the axles and use a
small bead of epoxy to hold them in place.
Trace two fuselage-side outlines on lightweight 1⁄16 sheet
balsa. On each side, mark the location of all 1⁄16-inch square
verticals, the motor-mount nosepiece, and the wing hold-down
supports. Now you are ready to join the fuselage sides. Make sure
to incorporate 5° of negative incidence when installing and gluing
the nosepiece.
Cut the equipment tray from 1⁄16-inch sheet balsa, and double
the servo location with cross-grained balsa. The balsa equipment
tray rests on the rear portion of the landing-gear assembly.
Glue in place, and measure and cut all 1⁄16-inch fuselage
crossbraces. Since the portion of the fuselage under the wing
must fit between the wing’s center-section, test-fit before
you glue those crossbraces. The crossbraces under the
wing must be at least 3⁄8 inch below the fuselage top to
provide sufficient clearance. When crossbracing is
complete, attach Velcro strips in place to hold down
the speed controller, receiver, and battery.
Do not install 1⁄16 sheet balsa (cross-grained) on the
top and bottom of the fuselage nose area until the motor
and speed controller have been installed. Finally, bend
and install the piano-wire tail skid, and carefully sand the
fuselage.
Before setting it aside for later installation of the motor and
radio equipment, test-fit the wing onto the fuselage. It will
require a 1⁄8 x 3⁄16-inch notch just behind the LE at the bottom of
the center double rib to permit clearance over the landing-gear
bulkhead.
Equipment Installation: The light flyer aspect of this hobby has
20 MODEL AVIATION
The author recommends that you employ either Litespan or GM
Tissue as covering materials. They are both light and strong.
Type: Indoor electric sport
Wingspan: 45 inches
Power: GWS A or geared DC 1717 motor
Flying weight: 6-8 ounces
Construction: Built-up balsa
Covering/finish: Litespan or GM Tissue
07sig1.QXD 4/26/04 10:02 am Page 20
become so popular that there is a wide range of appropriate
electric motors available. In my first test model I used a DC
1717, which was geared and weighed 21 grams, but it seemed to
lack sufficient thrust using a 9.4 x 7 carbon propeller.
During the time I was testing ITSA BIRD, GWS came out
with a new series of small but extremely efficient motors. I
installed a GWS A and used the GWS 10 x 4.7 plastic propeller.
This motor has an external 5.86:1 gear ratio and provides more
than ample thrust. Using the GWS motor required modification
of the nose section, as illustrated on the plans, and a change to 3°
of negative incidence.
I also replaced a seven-cell 50 mAh Ni-Cd battery pack with
an eight-cell 280 mAh NiMH battery pack stacked four over four.
It weighs the same and provides twice the flying time.
Depending on whether you use a push-pull or a pull-pull
system of controlling tail surfaces, you may have to install balsa
exit guides in the fuselage and elevator. I chose to use 1.5mm
(0.06-inch) carbon pushrods that were stiff enough to negate the
use of interior fuselage guides.
I chose to use the Hitec HAS-3MB
super-narrow-band three-channel receiver
on 27 MHz and removed the top cover to
save weight. Two Hitec HS-50 servos
worked perfectly. I tested an Alpex-4FM
microreceiver (72 MHz), and it worked
well. I selected a Castle Creations Pixie-14
speed controller, but there are many
comparable units on the market.
I attached the battery, receiver, and
speed controller using Velcro. I
incorporated 1⁄2-inch deflection in the
elevator and 3⁄4-inch deflection in the
rudder to permit tight turns.
Covering: Since weight is critical, use a
lightweight covering such as Litespan or
GM (Gas Model) Tissue; both are heatshrinkable
but require that you apply
Balsarite or Sig Stix-It to the framework.
Cover only the top of the wing and
elevator. Cover the rudder on both sides.
Be extremely careful when applying heat
to prevent warping.
Once the elevator and rudder are
covered, install the hinges and horns. Do
not cover the fuselage section under the
wing or where the radio-equipment
compartment is located. Glue the rudder
and elevator to the fuselage.
Flying: Attach the wing using thin rubber
bands. I found that two No. 18 bands tied
together and crisscrossed over the wing
work well. Before flying, make sure the
balance is correct. If adjustment is needed,
using Velcro permits the battery to be
moved accordingly.
After I checked the balance and the
motor and radio equipment were
functioning properly, I made the first test
flight. ITSA BIRD broke ground after a
roll of 10-15 feet. Once level flight was
obtained and I attempted left and right
turns, half throttle was more than
sufficient and a smooth, tight Figure Eight
was easily attainable. You should make
every effort to prevent dead-stick landings,
so be sure to retain power until
touchdown.
Subsequent flights lasted longer than 12 minutes using the
NiMH batteries. If you fly outdoors, try to select a wind-free day
and stay away from moving trees. MA
Larry Katz
1658 Buttonwood Ave.
Toms River NJ 08755
July 2004 21
ITSA BIRD is at home below the beams in any large indoor flying site. It can also be
flown outdoors on calm days. It will turn heads wherever you fly it!
Servo, receiver, and battery access is accomplished through an opening in the bottom
of the aircraft’s fuselage. This installation is practical and simple.
Sources:
Balsa Products
122 Jansen Ave.
Iselin NJ 08830
David Lewis
4027 Rocky River 26
Cleveland OH 44135
Hitec, RCD, Inc.
12115 Paine St.
Poway CA 92064
Castle Creations
402 E. Pendleton Ave.
Wellsville KS 66092
K&S Engineering
6917 W. 59 St.
Chicago IL 60638
Don Post Batteries
1772 Buttonwood Ave.
Toms River NJ 08755
07sig1.QXD 4/26/04 10:03 am Page 21
22 MODEL AVIATION
The stabilizer and elevator are built from balsa strip stock over
the plans as shown. They’re light but sturdy!
The fin and rudder are shown assembled. Notice that the tail
feathers combine to augment the birdlike look.
Unusual? You bet, and that’s hard to achieve these days! Note
extra-long landing gear for good propeller clearance.
The wing has plenty of area, and at the 6- to 8-ounce flying
weight, ITSA BIRD will yield great slow-flight characteristics.
The two fuselage sides are ready for construction. The landing
gear is lashed to a former before assembly.
The laminated LEs and TEs are pinned over the wing outline on
the plans as shown. It takes a great deal of pins!
Stack-sanded ribs have been cut and fit to the framework. The outer-section dihedral has been added and the spar has
been installed. You know, it does look like a bird!
Photos courtesy the author
07sig1.QXD 4/26/04 10:04 am Page 22
Edition: Model Aviation - 2004/07
Page Numbers: 19,20,21,22,23
July 2004 19
THE IDEA FOR this model was derived
from an airplane that Igo Etrich designed in
1912. His inspiration came not from a bird
but from a palm tree. Its seeds were winged,
and as he watched them fall, he felt sure that
they had an aerodynamic design he could use
for an airplane. Etrich’s aircraft looked
more like a bird than a flying seed; hence its
name—the “Taube”—meaning dove. In
flight, the graceful outline justified the name,
but a closer look revealed that the machine
was covered with wires. Etrich gave up his
claim to the design’s copyright, and the
airplane proved to be the father of many
future airplanes, including ITSA BIRD.
CONSTRUCTION
This model’s construction is basic;
however, the materials’ weight is critical to
obtain maximum performance. Therefore,
you should make every effort to use 4- to 6-
pound, lightweight balsa stock for sheet and
for sticks.
Wing: Before commencing construction,
photocopy the wing ribs section and cover the
plans with waxed paper or plastic film. Use a
light coat of rubber cement or 3M Super 77
Spray Adhesive to tack the outlines onto 1⁄16
sheet balsa. For ribs WR1 and WR3, it is
helpful to cut templates from 1⁄16 plywood.
Since most ribs require a bit of trimming
for a proper fit, lengthen each approximately
1⁄4 inch when cutting them out. After cutting
out all the ribs, stack and sand them so that
little or no sanding will be needed after the
framework is finished.
You construct the LEs and TEs by
laminating three strips of 1⁄16 x 1⁄4 balsa. To
increase their flexibility, soak them in warm
water or a 50/50 solution of ammonia and
water. Use a slightly watered-down mixture
of Elmer’s Carpenter’s Wood Glue or
Franklin Titebond wood glue to laminate.
After you have pinned and glued the
entire LE and TE, cut both edges at the
dihedral breaks to produce 30° angles. Cut
Author with
his model,
ready for
indoor flight.
Idea for wing
shape
originally
came from a
palm-tree
seed in
1912!
by Larry Katz
07sig1.QXD 4/26/04 10:01 am Page 19
and glue each rib in place. Omit the double ribs WR3 until the
dihedral is set. Leave the center-section pinned to the plans, and
raise each wingtip 41⁄2 inches and glue in place. At this time you
can install ribs WR3 and all wing gussets.
Before removing the structure from the plans, install the 1⁄16-
inch square spar and sheet the center-section (top only). When the
wing is dry, remove it from the plans and round it by trimming,
shaping, and sanding the entire LE and TE. Set aside for
covering.
Tail Feathers: Elevator and rudder construction are basic. Either
3⁄32 or 1⁄8 square balsa will produce structures with little or no
weight difference, as long as it is lightweight. The plans indicate
the use of Sig Easy Hinges, but any comparable hinge is
satisfactory.
I used thin sheet aluminum to form rudder and elevator horns.
A good source for this material is the top of certain packaged
products. I obtained my aluminum from a can of French’s French
Fried Onions. You can also make horns from 1⁄32 plywood. Before
you install the horns, sand the rudder and elevator.
Fuselage: Before you begin fuselage construction, cut the motormount
nosepiece from 1⁄16 plywood and cut a hole large enough to
accept whatever motor you intend to use. I also advise you to
construct the landing-gear assembly at this time. This step
requires you to cut formers F1, F2, F3, and two lengths of 1.5mm
carbon rod. Exercise caution when cutting carbon; it is best to
place masking tape at the point of cut, and use a Dremel or
similar tool.
Cut and bend 0.1mm piano wire for the wheel axles, tie it to
the rods with buttonhole thread, and glue it in place. For a neater
application you can cover this section with 1⁄16-inch heat-shrink
tubing, but it is not necessary.
I chose 17⁄8-inch-diameter GWS wheels. They will operate
better and with less friction if you insert 1⁄4-inch lengths of 1⁄16-
inch aluminum or brass tubing into each hub.
Epoxy the carbon landing gears into a sandwich created by
formers F1, F2, and F3. Make sure that both are aligned correctly.
When they are dry, slip the GWS wheels on the axles and use a
small bead of epoxy to hold them in place.
Trace two fuselage-side outlines on lightweight 1⁄16 sheet
balsa. On each side, mark the location of all 1⁄16-inch square
verticals, the motor-mount nosepiece, and the wing hold-down
supports. Now you are ready to join the fuselage sides. Make sure
to incorporate 5° of negative incidence when installing and gluing
the nosepiece.
Cut the equipment tray from 1⁄16-inch sheet balsa, and double
the servo location with cross-grained balsa. The balsa equipment
tray rests on the rear portion of the landing-gear assembly.
Glue in place, and measure and cut all 1⁄16-inch fuselage
crossbraces. Since the portion of the fuselage under the wing
must fit between the wing’s center-section, test-fit before
you glue those crossbraces. The crossbraces under the
wing must be at least 3⁄8 inch below the fuselage top to
provide sufficient clearance. When crossbracing is
complete, attach Velcro strips in place to hold down
the speed controller, receiver, and battery.
Do not install 1⁄16 sheet balsa (cross-grained) on the
top and bottom of the fuselage nose area until the motor
and speed controller have been installed. Finally, bend
and install the piano-wire tail skid, and carefully sand the
fuselage.
Before setting it aside for later installation of the motor and
radio equipment, test-fit the wing onto the fuselage. It will
require a 1⁄8 x 3⁄16-inch notch just behind the LE at the bottom of
the center double rib to permit clearance over the landing-gear
bulkhead.
Equipment Installation: The light flyer aspect of this hobby has
20 MODEL AVIATION
The author recommends that you employ either Litespan or GM
Tissue as covering materials. They are both light and strong.
Type: Indoor electric sport
Wingspan: 45 inches
Power: GWS A or geared DC 1717 motor
Flying weight: 6-8 ounces
Construction: Built-up balsa
Covering/finish: Litespan or GM Tissue
07sig1.QXD 4/26/04 10:02 am Page 20
become so popular that there is a wide range of appropriate
electric motors available. In my first test model I used a DC
1717, which was geared and weighed 21 grams, but it seemed to
lack sufficient thrust using a 9.4 x 7 carbon propeller.
During the time I was testing ITSA BIRD, GWS came out
with a new series of small but extremely efficient motors. I
installed a GWS A and used the GWS 10 x 4.7 plastic propeller.
This motor has an external 5.86:1 gear ratio and provides more
than ample thrust. Using the GWS motor required modification
of the nose section, as illustrated on the plans, and a change to 3°
of negative incidence.
I also replaced a seven-cell 50 mAh Ni-Cd battery pack with
an eight-cell 280 mAh NiMH battery pack stacked four over four.
It weighs the same and provides twice the flying time.
Depending on whether you use a push-pull or a pull-pull
system of controlling tail surfaces, you may have to install balsa
exit guides in the fuselage and elevator. I chose to use 1.5mm
(0.06-inch) carbon pushrods that were stiff enough to negate the
use of interior fuselage guides.
I chose to use the Hitec HAS-3MB
super-narrow-band three-channel receiver
on 27 MHz and removed the top cover to
save weight. Two Hitec HS-50 servos
worked perfectly. I tested an Alpex-4FM
microreceiver (72 MHz), and it worked
well. I selected a Castle Creations Pixie-14
speed controller, but there are many
comparable units on the market.
I attached the battery, receiver, and
speed controller using Velcro. I
incorporated 1⁄2-inch deflection in the
elevator and 3⁄4-inch deflection in the
rudder to permit tight turns.
Covering: Since weight is critical, use a
lightweight covering such as Litespan or
GM (Gas Model) Tissue; both are heatshrinkable
but require that you apply
Balsarite or Sig Stix-It to the framework.
Cover only the top of the wing and
elevator. Cover the rudder on both sides.
Be extremely careful when applying heat
to prevent warping.
Once the elevator and rudder are
covered, install the hinges and horns. Do
not cover the fuselage section under the
wing or where the radio-equipment
compartment is located. Glue the rudder
and elevator to the fuselage.
Flying: Attach the wing using thin rubber
bands. I found that two No. 18 bands tied
together and crisscrossed over the wing
work well. Before flying, make sure the
balance is correct. If adjustment is needed,
using Velcro permits the battery to be
moved accordingly.
After I checked the balance and the
motor and radio equipment were
functioning properly, I made the first test
flight. ITSA BIRD broke ground after a
roll of 10-15 feet. Once level flight was
obtained and I attempted left and right
turns, half throttle was more than
sufficient and a smooth, tight Figure Eight
was easily attainable. You should make
every effort to prevent dead-stick landings,
so be sure to retain power until
touchdown.
Subsequent flights lasted longer than 12 minutes using the
NiMH batteries. If you fly outdoors, try to select a wind-free day
and stay away from moving trees. MA
Larry Katz
1658 Buttonwood Ave.
Toms River NJ 08755
July 2004 21
ITSA BIRD is at home below the beams in any large indoor flying site. It can also be
flown outdoors on calm days. It will turn heads wherever you fly it!
Servo, receiver, and battery access is accomplished through an opening in the bottom
of the aircraft’s fuselage. This installation is practical and simple.
Sources:
Balsa Products
122 Jansen Ave.
Iselin NJ 08830
David Lewis
4027 Rocky River 26
Cleveland OH 44135
Hitec, RCD, Inc.
12115 Paine St.
Poway CA 92064
Castle Creations
402 E. Pendleton Ave.
Wellsville KS 66092
K&S Engineering
6917 W. 59 St.
Chicago IL 60638
Don Post Batteries
1772 Buttonwood Ave.
Toms River NJ 08755
07sig1.QXD 4/26/04 10:03 am Page 21
22 MODEL AVIATION
The stabilizer and elevator are built from balsa strip stock over
the plans as shown. They’re light but sturdy!
The fin and rudder are shown assembled. Notice that the tail
feathers combine to augment the birdlike look.
Unusual? You bet, and that’s hard to achieve these days! Note
extra-long landing gear for good propeller clearance.
The wing has plenty of area, and at the 6- to 8-ounce flying
weight, ITSA BIRD will yield great slow-flight characteristics.
The two fuselage sides are ready for construction. The landing
gear is lashed to a former before assembly.
The laminated LEs and TEs are pinned over the wing outline on
the plans as shown. It takes a great deal of pins!
Stack-sanded ribs have been cut and fit to the framework. The outer-section dihedral has been added and the spar has
been installed. You know, it does look like a bird!
Photos courtesy the author
07sig1.QXD 4/26/04 10:04 am Page 22
Edition: Model Aviation - 2004/07
Page Numbers: 19,20,21,22,23
July 2004 19
THE IDEA FOR this model was derived
from an airplane that Igo Etrich designed in
1912. His inspiration came not from a bird
but from a palm tree. Its seeds were winged,
and as he watched them fall, he felt sure that
they had an aerodynamic design he could use
for an airplane. Etrich’s aircraft looked
more like a bird than a flying seed; hence its
name—the “Taube”—meaning dove. In
flight, the graceful outline justified the name,
but a closer look revealed that the machine
was covered with wires. Etrich gave up his
claim to the design’s copyright, and the
airplane proved to be the father of many
future airplanes, including ITSA BIRD.
CONSTRUCTION
This model’s construction is basic;
however, the materials’ weight is critical to
obtain maximum performance. Therefore,
you should make every effort to use 4- to 6-
pound, lightweight balsa stock for sheet and
for sticks.
Wing: Before commencing construction,
photocopy the wing ribs section and cover the
plans with waxed paper or plastic film. Use a
light coat of rubber cement or 3M Super 77
Spray Adhesive to tack the outlines onto 1⁄16
sheet balsa. For ribs WR1 and WR3, it is
helpful to cut templates from 1⁄16 plywood.
Since most ribs require a bit of trimming
for a proper fit, lengthen each approximately
1⁄4 inch when cutting them out. After cutting
out all the ribs, stack and sand them so that
little or no sanding will be needed after the
framework is finished.
You construct the LEs and TEs by
laminating three strips of 1⁄16 x 1⁄4 balsa. To
increase their flexibility, soak them in warm
water or a 50/50 solution of ammonia and
water. Use a slightly watered-down mixture
of Elmer’s Carpenter’s Wood Glue or
Franklin Titebond wood glue to laminate.
After you have pinned and glued the
entire LE and TE, cut both edges at the
dihedral breaks to produce 30° angles. Cut
Author with
his model,
ready for
indoor flight.
Idea for wing
shape
originally
came from a
palm-tree
seed in
1912!
by Larry Katz
07sig1.QXD 4/26/04 10:01 am Page 19
and glue each rib in place. Omit the double ribs WR3 until the
dihedral is set. Leave the center-section pinned to the plans, and
raise each wingtip 41⁄2 inches and glue in place. At this time you
can install ribs WR3 and all wing gussets.
Before removing the structure from the plans, install the 1⁄16-
inch square spar and sheet the center-section (top only). When the
wing is dry, remove it from the plans and round it by trimming,
shaping, and sanding the entire LE and TE. Set aside for
covering.
Tail Feathers: Elevator and rudder construction are basic. Either
3⁄32 or 1⁄8 square balsa will produce structures with little or no
weight difference, as long as it is lightweight. The plans indicate
the use of Sig Easy Hinges, but any comparable hinge is
satisfactory.
I used thin sheet aluminum to form rudder and elevator horns.
A good source for this material is the top of certain packaged
products. I obtained my aluminum from a can of French’s French
Fried Onions. You can also make horns from 1⁄32 plywood. Before
you install the horns, sand the rudder and elevator.
Fuselage: Before you begin fuselage construction, cut the motormount
nosepiece from 1⁄16 plywood and cut a hole large enough to
accept whatever motor you intend to use. I also advise you to
construct the landing-gear assembly at this time. This step
requires you to cut formers F1, F2, F3, and two lengths of 1.5mm
carbon rod. Exercise caution when cutting carbon; it is best to
place masking tape at the point of cut, and use a Dremel or
similar tool.
Cut and bend 0.1mm piano wire for the wheel axles, tie it to
the rods with buttonhole thread, and glue it in place. For a neater
application you can cover this section with 1⁄16-inch heat-shrink
tubing, but it is not necessary.
I chose 17⁄8-inch-diameter GWS wheels. They will operate
better and with less friction if you insert 1⁄4-inch lengths of 1⁄16-
inch aluminum or brass tubing into each hub.
Epoxy the carbon landing gears into a sandwich created by
formers F1, F2, and F3. Make sure that both are aligned correctly.
When they are dry, slip the GWS wheels on the axles and use a
small bead of epoxy to hold them in place.
Trace two fuselage-side outlines on lightweight 1⁄16 sheet
balsa. On each side, mark the location of all 1⁄16-inch square
verticals, the motor-mount nosepiece, and the wing hold-down
supports. Now you are ready to join the fuselage sides. Make sure
to incorporate 5° of negative incidence when installing and gluing
the nosepiece.
Cut the equipment tray from 1⁄16-inch sheet balsa, and double
the servo location with cross-grained balsa. The balsa equipment
tray rests on the rear portion of the landing-gear assembly.
Glue in place, and measure and cut all 1⁄16-inch fuselage
crossbraces. Since the portion of the fuselage under the wing
must fit between the wing’s center-section, test-fit before
you glue those crossbraces. The crossbraces under the
wing must be at least 3⁄8 inch below the fuselage top to
provide sufficient clearance. When crossbracing is
complete, attach Velcro strips in place to hold down
the speed controller, receiver, and battery.
Do not install 1⁄16 sheet balsa (cross-grained) on the
top and bottom of the fuselage nose area until the motor
and speed controller have been installed. Finally, bend
and install the piano-wire tail skid, and carefully sand the
fuselage.
Before setting it aside for later installation of the motor and
radio equipment, test-fit the wing onto the fuselage. It will
require a 1⁄8 x 3⁄16-inch notch just behind the LE at the bottom of
the center double rib to permit clearance over the landing-gear
bulkhead.
Equipment Installation: The light flyer aspect of this hobby has
20 MODEL AVIATION
The author recommends that you employ either Litespan or GM
Tissue as covering materials. They are both light and strong.
Type: Indoor electric sport
Wingspan: 45 inches
Power: GWS A or geared DC 1717 motor
Flying weight: 6-8 ounces
Construction: Built-up balsa
Covering/finish: Litespan or GM Tissue
07sig1.QXD 4/26/04 10:02 am Page 20
become so popular that there is a wide range of appropriate
electric motors available. In my first test model I used a DC
1717, which was geared and weighed 21 grams, but it seemed to
lack sufficient thrust using a 9.4 x 7 carbon propeller.
During the time I was testing ITSA BIRD, GWS came out
with a new series of small but extremely efficient motors. I
installed a GWS A and used the GWS 10 x 4.7 plastic propeller.
This motor has an external 5.86:1 gear ratio and provides more
than ample thrust. Using the GWS motor required modification
of the nose section, as illustrated on the plans, and a change to 3°
of negative incidence.
I also replaced a seven-cell 50 mAh Ni-Cd battery pack with
an eight-cell 280 mAh NiMH battery pack stacked four over four.
It weighs the same and provides twice the flying time.
Depending on whether you use a push-pull or a pull-pull
system of controlling tail surfaces, you may have to install balsa
exit guides in the fuselage and elevator. I chose to use 1.5mm
(0.06-inch) carbon pushrods that were stiff enough to negate the
use of interior fuselage guides.
I chose to use the Hitec HAS-3MB
super-narrow-band three-channel receiver
on 27 MHz and removed the top cover to
save weight. Two Hitec HS-50 servos
worked perfectly. I tested an Alpex-4FM
microreceiver (72 MHz), and it worked
well. I selected a Castle Creations Pixie-14
speed controller, but there are many
comparable units on the market.
I attached the battery, receiver, and
speed controller using Velcro. I
incorporated 1⁄2-inch deflection in the
elevator and 3⁄4-inch deflection in the
rudder to permit tight turns.
Covering: Since weight is critical, use a
lightweight covering such as Litespan or
GM (Gas Model) Tissue; both are heatshrinkable
but require that you apply
Balsarite or Sig Stix-It to the framework.
Cover only the top of the wing and
elevator. Cover the rudder on both sides.
Be extremely careful when applying heat
to prevent warping.
Once the elevator and rudder are
covered, install the hinges and horns. Do
not cover the fuselage section under the
wing or where the radio-equipment
compartment is located. Glue the rudder
and elevator to the fuselage.
Flying: Attach the wing using thin rubber
bands. I found that two No. 18 bands tied
together and crisscrossed over the wing
work well. Before flying, make sure the
balance is correct. If adjustment is needed,
using Velcro permits the battery to be
moved accordingly.
After I checked the balance and the
motor and radio equipment were
functioning properly, I made the first test
flight. ITSA BIRD broke ground after a
roll of 10-15 feet. Once level flight was
obtained and I attempted left and right
turns, half throttle was more than
sufficient and a smooth, tight Figure Eight
was easily attainable. You should make
every effort to prevent dead-stick landings,
so be sure to retain power until
touchdown.
Subsequent flights lasted longer than 12 minutes using the
NiMH batteries. If you fly outdoors, try to select a wind-free day
and stay away from moving trees. MA
Larry Katz
1658 Buttonwood Ave.
Toms River NJ 08755
July 2004 21
ITSA BIRD is at home below the beams in any large indoor flying site. It can also be
flown outdoors on calm days. It will turn heads wherever you fly it!
Servo, receiver, and battery access is accomplished through an opening in the bottom
of the aircraft’s fuselage. This installation is practical and simple.
Sources:
Balsa Products
122 Jansen Ave.
Iselin NJ 08830
David Lewis
4027 Rocky River 26
Cleveland OH 44135
Hitec, RCD, Inc.
12115 Paine St.
Poway CA 92064
Castle Creations
402 E. Pendleton Ave.
Wellsville KS 66092
K&S Engineering
6917 W. 59 St.
Chicago IL 60638
Don Post Batteries
1772 Buttonwood Ave.
Toms River NJ 08755
07sig1.QXD 4/26/04 10:03 am Page 21
22 MODEL AVIATION
The stabilizer and elevator are built from balsa strip stock over
the plans as shown. They’re light but sturdy!
The fin and rudder are shown assembled. Notice that the tail
feathers combine to augment the birdlike look.
Unusual? You bet, and that’s hard to achieve these days! Note
extra-long landing gear for good propeller clearance.
The wing has plenty of area, and at the 6- to 8-ounce flying
weight, ITSA BIRD will yield great slow-flight characteristics.
The two fuselage sides are ready for construction. The landing
gear is lashed to a former before assembly.
The laminated LEs and TEs are pinned over the wing outline on
the plans as shown. It takes a great deal of pins!
Stack-sanded ribs have been cut and fit to the framework. The outer-section dihedral has been added and the spar has
been installed. You know, it does look like a bird!
Photos courtesy the author
07sig1.QXD 4/26/04 10:04 am Page 22