Moffett Redux - 2003/10

Re 42 MODEL AVIATION
Close-up of stabilizer in DT position. Site is Northern California
Free Flight Council field near Sacramento.
Rubber band attached to end of pivot wire loops over hook shown
in fuselage side and snaps takeoff peg to retracted position.
■ William Langenberg
Competitive model for resurging
FF event from the 1930s
Moffett
ear Admiral William A. Moffett headed the US Navy’s
Bureau of Aeronautics from its inception in 1921 until his
death in 1933. His primary duty during that assignment was
to effectively integrate fledgling naval aviation into fleet
operations.
Former skipper of the cruiser USS Chester and the
battleship USS Mississippi, Moffett was surprisingly not a
qualified naval aviator. However, during the 1920s and 1930s he
became one of the Navy’s best-known and most articulate navalaviation
supporters.
Perhaps most closely associated in the public’s mind with rigid
airships, commonly known as dirigibles, Moffett was killed in the
crash of the USS Akron off the New Jersey coast in April 1933.
Because of his support for aviation, an international Free Flight
model-airplane competition bearing his name began in the 1930s. It
was held as an annual event at the AMA Nationals and featured
teams of six candidates from the US, Canada, England, Australia,
and New Zealand. Participants for the latter three nations were
frequently represented by American proxy fliers.
The Moffett competition languished after World War II, but it
was reincarnated as an official National Free Flight Society (NFFS)
event in 1992. The simple rules are:
1) The wing and stabilizer area must not exceed 202 square
inches.
2) The distance between the propeller thrust bearing and the aft
end of the stabilizer, fin, or fuselage must not exceed the
projected wingspan.
3) The fuselage cross-section at the point of the maximum area
must be at least the length squared divided by 150.
4) The airframe weight must be at least 1.74 ounces per 100
square inches of projected wing area.
5) There is no limit on rubber motor weight.
6) The model must stand unassisted on three points.
7) All championship and record flights must rise-off-ground
(ROG) with no push.
The contemporary Moffett rules are attractive to me because they
give a designer considerable freedom to conceive and construct a
competitive model. As did the pre-1956 Wakefields, they reward a
modeler who can build a light, durable airplane and power it with a
rubber motor that approaches the airframe weight.
Once a flier masters the challenge of the ROG launch,
particularly in wind, the result is a high-performance model that is
easily capable of achieving the necessary three-minute-maximum
flights.
If this preamble and the accompanying photographs of the Moffett
Redux have piqued your interest, the following suggestions may help
you create a competitive model—one that is easy to trim and fly.
October 2003 43
Model in takeoff position. Wide fuselage, boxy wing mount are
necessary to meet minimum cross-section required by rules.
ID label on side of pylon attests to compliance with wing plus
stabilizer area and fuselage cross-section rules.
R
dux
October 2003 45
CONSTRUCTION
Stabilizer: Begin with the stabilizer so that it
can be covered, doped, and cured before you
attempt any test flights. Use contest-grade
balsa to keep weight down. During assembly,
the front of the trailing edge should be packed
up to conform with the airfoil as shown on the
plans. Assemble the parts on a flat surface,
adding the spruce dethermalizer (DT) hooks
as the last operation.
Carefully sand the stabilizer, and cover it
with tissue. You should add the tip plates
before the tissue is water-sprayed, and you
should give the entire structure at least three
coats of thinned dope. I normally prefer nitrate
to butyrate dope because it appears more
resistant to moisture in the air.
The completed stabilizer should be free of
warps. The finished weight should not exceed
8 grams, including the attached fin.
Wing: The wing is next in the construction
sequence. It is straightforward and should
present few building problems. Select the
wood with care; the structure should be kept
as light as possible. Ribs are cut from 1⁄16
quarter-grain stock. The trailing edge is made
from similar 1⁄8 sheet balsa.
As on the stabilizer, pack up the front of
the trailing edge to conform to the proper
airfoil shape. Using liberal amounts of glue on
all joints, join the wing panels to the
polyhedral dimensions indicated. Do not
cement spars to the ribs at the polyhedral
breaks until the panels are blocked up to the
proper angles.
Install the center basswood gusset and
triangular balsa reinforcements as shown.
Carve the wingtips from soft 3⁄8 sheet balsa,
then cautiously sand the entire completed
structure to facilitate an attractive covering
job. Cover the wing with good-quality tissue.
As with the stabilizer, apply at least three coats
of nitrate dope. Set the wing aside and allow it
to cure thoroughly.
Each outboard wing panel should have 1⁄8
inch of washout, which should occur naturally
as the doped covering cures. The finished
weight ought not to exceed 19 grams.
Remember that the maximum projected
area of the wing and stabilizer is 202
square inches. Trim off of the wing trailing
edge to meet this parameter if necessary.
Fin: Cut the fin from soft 3⁄32 sheet balsa to the
outline shown on the plans. It should be
carved and sanded to a streamlined shape as
indicated, to give a left turn in the glide. Glue
it to the top of the doubled center stabilizer rib,
ensuring that it is perpendicular.
Fuselage: Select four hard 3⁄32 x 3⁄32-inch balsa
strips for the longerons. I used spruce
longerons for durability, but what you use is
your preference. Build two fuselage sides on
the plans, ensuring that the diagonals do not
run the same direction on both sides. Add the
3⁄32-inch sheet fillers for the rear rubber peg
and nose area.
When joining the fuselage sides, tack-glue
3⁄32 x 3⁄32-inch crosspieces to the longerons
approximately every eight inches, to set up the
fuselage shape throughout the length of its
square section.
Insert the 3⁄32 x 3⁄32-inch diagonals,
proceeding equally along the top and bottom.
You can remove the tack-glued 3⁄32 x 3⁄32-inch
pieces as diagonals take their places. If you
prefer, a simple fixture can be constructed to
facilitate fuselage assembly.
Add the 3⁄32 sheet balsa fillers at the front
top and bottom of the fuselage, then glue the
remainder of the diagonals in place. Insert the
1⁄8-sheet-balsa reinforcing pieces, with their 1⁄8
plywood inserts, inside the rear motor-peg
section as indicated on the plans.
Carve and sand 3⁄32-inch right thrust into
the fuselage nose. Cut out the 1⁄16 plywood
nose former and glue it accurately in place.
Sand the entire fuselage smooth, and cover it
with Polyspan or equal. For durability you
may want to double-cover the fuselage
bottom, cross-graining the Polyspan.
To finish the fuselage, cut out the wing
mounts and the stabilizer platform. Glue them
to the fuselage as shown, then add the 1⁄16-inch
aluminum tubing DT line guides and the 1⁄16-
inch-diameter dowel rubber hooks for the
wing attachment and stabilizer DT system.
The mini-timer shown in the photographs
weighs 6 grams. If you elect to use one, you
should position it on the wing mount; if it is
mounted on the fuselage side, the unwinding
rubber motor disrupts its accuracy.
The single-peg retracting landing gear is
not nearly as difficult to build as it may look to
a neophyte. Cut a 17-inch peg from 1⁄8 square
spruce. This peg is actuated by a 1⁄32-inchdiameter
music-wire hinge, which is epoxied
to the peg then bent at right angles and run
through 1⁄32-inch-inside-diameter brass tubing
cut to the width of the fuselage. The tubing is
epoxied to the fuselage at the bottom
crossbrace forward of the wing, ensuring that
the hinge wire can turn freely within it.
Carefully conforming to the close-up
photographs, with the peg on the right side of
the fuselage, bend the 1⁄32-inch-diameter wire
at right angles to the tubing. Shape a small
hook into its end so that the short rubber band
on the left side of the fuselage can snap it into
retracted position after takeoff.
Glue a small piece of 1⁄32 plywood to the
peg, as shown, to serve as a retraction stop.
Likewise, a 1⁄16-inch-diameter dowel running
across the fuselage above the pivot tubing
serves as a forward motion stop for the peg
during ROG launch.
If you are a rubber-powered-model flier
who has never used a retracting-peg system,
you may be apprehensive of doing so at first.
However, be assured that if the model is built
as shown without excessive weight, it will
spring into the air on the power burst with few
problems.
The fuselage’s finished weight, including
retracting-peg landing gear, should not exceed
50 grams with a DT mini-timer.
Propeller Assembly: The model shown in the
photographs uses a 171⁄2-inch-diameter
Superior Props prebuilt folding propeller with
the blades trimmed to the outline shown. An
alternative propeller, for those more
experienced or energetic modelers who want
to carve their own, is also detailed on the
plans.
If you elect to carve the propeller, select a
straight-grained 11⁄2 x 2 x 171⁄2-inch balsa
block. Drill the center shaft hole, then saw the
blank to shape. Carve the aft concave surfaces
with roughly 1⁄16 inch of undercamber and
sand them smooth, ensuring that the two
blades are symmetrical.
Carve away the front sides of the propeller
until the blades are approximately 3⁄32-inch
thick at midpoint. Shape the blades to the
finished outline. Details of the folding
Model on winding stooge. Takeoff peg is in fully retracted
position; dowel stop protrudes from fuselage’s right side.
Serious competitors should get stooge and sturdy winder. One
shown has integral counter, torque meter, extended crank arm.
Photos courtesy the author Graphic Design by Lydia Whitehead
mechanism are shown in the accompanying
photographs.
Complete the propeller assembly by
carving the nose block from hard balsa, with
its grain parallel to the fuselage axis. You can
obtain the ball bearing, shaft, thrust bearing,
and spring shown from FAI Model Supply. A
1⁄8 plywood insert glued to the rear of the nose
block should fit into the front nose former.
The propeller and nose block should be given
at least three coats of dope before assembling.
Ensure that the propeller blades are
balanced and track properly. The finished
weight of the propeller assembly, including
the nose block, should not exceed 25 grams. A
total airframe weight of 102 grams, or 3.60
ounces, thus exceeds the required minimum
amount by a small margin.
Flight Preparation: Make at least two 3⁄16-
inch rubber motors of 16 strands, 32 inches
long. After washing, drying, and lubing the
motors, break them in initially using the
stationary stretch method.
To use that technique, hammer two large
nails—approximately six motor lengths
apart—securely into a fence. Stretch the motor
over the nails and leave them there for five to
10 minutes. The stretched motors should be
roughly 33 inches long.
Assemble the completed model and insert
a rubber motor. Check that the alignment and
thrust offset are correct. Verify the balance
point with the propeller blades folded. Shift
the position of the DT timer if necessary to
ensure that the balance point is located
precisely as shown on the plans.
For the modeler who is interested in
serious Moffett competition, a reliable, sturdy
winder and a winding stooge are musts. The
advantages of an immovable holder when
winding and freedom to test-fly alone are
significant.
Under calm conditions, hand-glide the
model and add packing under the stabilizer
leading or trailing edge until the model floats
with a slight left turn.
This model should be docile to adjust
under power. Start with approximately 200
turns. It should climb to the right, straighten
out just before the propeller folds, then glide
to the left. Use thrust adjustments and rudder
tab to obtain this pattern. Proceed in
increments until maximum turns are reached.
Under full power, the model should climb in a
steep right corkscrew, with the nose pointed
up until just before the propeller folds. Motor
run should be roughly 50 seconds.
One advantage of the Moffett Rubber class
is that the duration potential of the model
exceeds the flight maximum unless down air
is encountered. Therefore, unlike a
contemporary Wakefield, it is not essential to
wind the motor to capacity on every flight.
Nor is a blast tube necessary unless you
choose to use one for safety purposes.
I normally wind the motor on my Moffett
800-850 turns, depending on the feel of the
rubber. Maximum capacity, by contrast, is
approximately 900 turns. Because of its
smooth texture, FAI Model Supply rubber is
normally resilient and unlikely to break unless
mistreated. On several occasions I have used
the same motor for all three competitive
flights.
If you are unwilling or unable to build your
Moffett Redux down to the structural weight
shown on the plans and the climb suffers
accordingly, I suggest an increase in power to
18 strands. One of the real joys of the Moffett
Rubber event is to watch your model climb to
an impressive height, which it may not do
unless thermal-assisted if underpowered.
Good luck with your Moffett Redux. MA
William Langenberg
3189 Danville Blvd., Suite 285
Alamo CA 94507
Sources:
Balsa and spruce wood:
Sig Manufacturing Company, Inc.
Box 520
Montezuma IA 50170
(641) 623-5154
Rubber, hardware, covering material:
FAI Model Supply
Box 366
Sayre PA 18840
(570) 882-9873
Propellers:
Superior Props
516 Driftwood Cir.
Slidell LA 70458
(985) 726-9673
October 2003 47
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.

Re 42 MODEL AVIATION
Close-up of stabilizer in DT position. Site is Northern California
Free Flight Council field near Sacramento.
Rubber band attached to end of pivot wire loops over hook shown
in fuselage side and snaps takeoff peg to retracted position.
■ William Langenberg
Competitive model for resurging
FF event from the 1930s
Moffett
ear Admiral William A. Moffett headed the US Navy’s
Bureau of Aeronautics from its inception in 1921 until his
death in 1933. His primary duty during that assignment was
to effectively integrate fledgling naval aviation into fleet
operations.
Former skipper of the cruiser USS Chester and the
battleship USS Mississippi, Moffett was surprisingly not a
qualified naval aviator. However, during the 1920s and 1930s he
became one of the Navy’s best-known and most articulate navalaviation
supporters.
Perhaps most closely associated in the public’s mind with rigid
airships, commonly known as dirigibles, Moffett was killed in the
crash of the USS Akron off the New Jersey coast in April 1933.
Because of his support for aviation, an international Free Flight
model-airplane competition bearing his name began in the 1930s. It
was held as an annual event at the AMA Nationals and featured
teams of six candidates from the US, Canada, England, Australia,
and New Zealand. Participants for the latter three nations were
frequently represented by American proxy fliers.
The Moffett competition languished after World War II, but it
was reincarnated as an official National Free Flight Society (NFFS)
event in 1992. The simple rules are:
1) The wing and stabilizer area must not exceed 202 square
inches.
2) The distance between the propeller thrust bearing and the aft
end of the stabilizer, fin, or fuselage must not exceed the
projected wingspan.
3) The fuselage cross-section at the point of the maximum area
must be at least the length squared divided by 150.
4) The airframe weight must be at least 1.74 ounces per 100
square inches of projected wing area.
5) There is no limit on rubber motor weight.
6) The model must stand unassisted on three points.
7) All championship and record flights must rise-off-ground
(ROG) with no push.
The contemporary Moffett rules are attractive to me because they
give a designer considerable freedom to conceive and construct a
competitive model. As did the pre-1956 Wakefields, they reward a
modeler who can build a light, durable airplane and power it with a
rubber motor that approaches the airframe weight.
Once a flier masters the challenge of the ROG launch,
particularly in wind, the result is a high-performance model that is
easily capable of achieving the necessary three-minute-maximum
flights.
If this preamble and the accompanying photographs of the Moffett
Redux have piqued your interest, the following suggestions may help
you create a competitive model—one that is easy to trim and fly.
October 2003 43
Model in takeoff position. Wide fuselage, boxy wing mount are
necessary to meet minimum cross-section required by rules.
ID label on side of pylon attests to compliance with wing plus
stabilizer area and fuselage cross-section rules.
R
dux
October 2003 45
CONSTRUCTION
Stabilizer: Begin with the stabilizer so that it
can be covered, doped, and cured before you
attempt any test flights. Use contest-grade
balsa to keep weight down. During assembly,
the front of the trailing edge should be packed
up to conform with the airfoil as shown on the
plans. Assemble the parts on a flat surface,
adding the spruce dethermalizer (DT) hooks
as the last operation.
Carefully sand the stabilizer, and cover it
with tissue. You should add the tip plates
before the tissue is water-sprayed, and you
should give the entire structure at least three
coats of thinned dope. I normally prefer nitrate
to butyrate dope because it appears more
resistant to moisture in the air.
The completed stabilizer should be free of
warps. The finished weight should not exceed
8 grams, including the attached fin.
Wing: The wing is next in the construction
sequence. It is straightforward and should
present few building problems. Select the
wood with care; the structure should be kept
as light as possible. Ribs are cut from 1⁄16
quarter-grain stock. The trailing edge is made
from similar 1⁄8 sheet balsa.
As on the stabilizer, pack up the front of
the trailing edge to conform to the proper
airfoil shape. Using liberal amounts of glue on
all joints, join the wing panels to the
polyhedral dimensions indicated. Do not
cement spars to the ribs at the polyhedral
breaks until the panels are blocked up to the
proper angles.
Install the center basswood gusset and
triangular balsa reinforcements as shown.
Carve the wingtips from soft 3⁄8 sheet balsa,
then cautiously sand the entire completed
structure to facilitate an attractive covering
job. Cover the wing with good-quality tissue.
As with the stabilizer, apply at least three coats
of nitrate dope. Set the wing aside and allow it
to cure thoroughly.
Each outboard wing panel should have 1⁄8
inch of washout, which should occur naturally
as the doped covering cures. The finished
weight ought not to exceed 19 grams.
Remember that the maximum projected
area of the wing and stabilizer is 202
square inches. Trim off of the wing trailing
edge to meet this parameter if necessary.
Fin: Cut the fin from soft 3⁄32 sheet balsa to the
outline shown on the plans. It should be
carved and sanded to a streamlined shape as
indicated, to give a left turn in the glide. Glue
it to the top of the doubled center stabilizer rib,
ensuring that it is perpendicular.
Fuselage: Select four hard 3⁄32 x 3⁄32-inch balsa
strips for the longerons. I used spruce
longerons for durability, but what you use is
your preference. Build two fuselage sides on
the plans, ensuring that the diagonals do not
run the same direction on both sides. Add the
3⁄32-inch sheet fillers for the rear rubber peg
and nose area.
When joining the fuselage sides, tack-glue
3⁄32 x 3⁄32-inch crosspieces to the longerons
approximately every eight inches, to set up the
fuselage shape throughout the length of its
square section.
Insert the 3⁄32 x 3⁄32-inch diagonals,
proceeding equally along the top and bottom.
You can remove the tack-glued 3⁄32 x 3⁄32-inch
pieces as diagonals take their places. If you
prefer, a simple fixture can be constructed to
facilitate fuselage assembly.
Add the 3⁄32 sheet balsa fillers at the front
top and bottom of the fuselage, then glue the
remainder of the diagonals in place. Insert the
1⁄8-sheet-balsa reinforcing pieces, with their 1⁄8
plywood inserts, inside the rear motor-peg
section as indicated on the plans.
Carve and sand 3⁄32-inch right thrust into
the fuselage nose. Cut out the 1⁄16 plywood
nose former and glue it accurately in place.
Sand the entire fuselage smooth, and cover it
with Polyspan or equal. For durability you
may want to double-cover the fuselage
bottom, cross-graining the Polyspan.
To finish the fuselage, cut out the wing
mounts and the stabilizer platform. Glue them
to the fuselage as shown, then add the 1⁄16-inch
aluminum tubing DT line guides and the 1⁄16-
inch-diameter dowel rubber hooks for the
wing attachment and stabilizer DT system.
The mini-timer shown in the photographs
weighs 6 grams. If you elect to use one, you
should position it on the wing mount; if it is
mounted on the fuselage side, the unwinding
rubber motor disrupts its accuracy.
The single-peg retracting landing gear is
not nearly as difficult to build as it may look to
a neophyte. Cut a 17-inch peg from 1⁄8 square
spruce. This peg is actuated by a 1⁄32-inchdiameter
music-wire hinge, which is epoxied
to the peg then bent at right angles and run
through 1⁄32-inch-inside-diameter brass tubing
cut to the width of the fuselage. The tubing is
epoxied to the fuselage at the bottom
crossbrace forward of the wing, ensuring that
the hinge wire can turn freely within it.
Carefully conforming to the close-up
photographs, with the peg on the right side of
the fuselage, bend the 1⁄32-inch-diameter wire
at right angles to the tubing. Shape a small
hook into its end so that the short rubber band
on the left side of the fuselage can snap it into
retracted position after takeoff.
Glue a small piece of 1⁄32 plywood to the
peg, as shown, to serve as a retraction stop.
Likewise, a 1⁄16-inch-diameter dowel running
across the fuselage above the pivot tubing
serves as a forward motion stop for the peg
during ROG launch.
If you are a rubber-powered-model flier
who has never used a retracting-peg system,
you may be apprehensive of doing so at first.
However, be assured that if the model is built
as shown without excessive weight, it will
spring into the air on the power burst with few
problems.
The fuselage’s finished weight, including
retracting-peg landing gear, should not exceed
50 grams with a DT mini-timer.
Propeller Assembly: The model shown in the
photographs uses a 171⁄2-inch-diameter
Superior Props prebuilt folding propeller with
the blades trimmed to the outline shown. An
alternative propeller, for those more
experienced or energetic modelers who want
to carve their own, is also detailed on the
plans.
If you elect to carve the propeller, select a
straight-grained 11⁄2 x 2 x 171⁄2-inch balsa
block. Drill the center shaft hole, then saw the
blank to shape. Carve the aft concave surfaces
with roughly 1⁄16 inch of undercamber and
sand them smooth, ensuring that the two
blades are symmetrical.
Carve away the front sides of the propeller
until the blades are approximately 3⁄32-inch
thick at midpoint. Shape the blades to the
finished outline. Details of the folding
Model on winding stooge. Takeoff peg is in fully retracted
position; dowel stop protrudes from fuselage’s right side.
Serious competitors should get stooge and sturdy winder. One
shown has integral counter, torque meter, extended crank arm.
Photos courtesy the author Graphic Design by Lydia Whitehead
mechanism are shown in the accompanying
photographs.
Complete the propeller assembly by
carving the nose block from hard balsa, with
its grain parallel to the fuselage axis. You can
obtain the ball bearing, shaft, thrust bearing,
and spring shown from FAI Model Supply. A
1⁄8 plywood insert glued to the rear of the nose
block should fit into the front nose former.
The propeller and nose block should be given
at least three coats of dope before assembling.
Ensure that the propeller blades are
balanced and track properly. The finished
weight of the propeller assembly, including
the nose block, should not exceed 25 grams. A
total airframe weight of 102 grams, or 3.60
ounces, thus exceeds the required minimum
amount by a small margin.
Flight Preparation: Make at least two 3⁄16-
inch rubber motors of 16 strands, 32 inches
long. After washing, drying, and lubing the
motors, break them in initially using the
stationary stretch method.
To use that technique, hammer two large
nails—approximately six motor lengths
apart—securely into a fence. Stretch the motor
over the nails and leave them there for five to
10 minutes. The stretched motors should be
roughly 33 inches long.
Assemble the completed model and insert
a rubber motor. Check that the alignment and
thrust offset are correct. Verify the balance
point with the propeller blades folded. Shift
the position of the DT timer if necessary to
ensure that the balance point is located
precisely as shown on the plans.
For the modeler who is interested in
serious Moffett competition, a reliable, sturdy
winder and a winding stooge are musts. The
advantages of an immovable holder when
winding and freedom to test-fly alone are
significant.
Under calm conditions, hand-glide the
model and add packing under the stabilizer
leading or trailing edge until the model floats
with a slight left turn.
This model should be docile to adjust
under power. Start with approximately 200
turns. It should climb to the right, straighten
out just before the propeller folds, then glide
to the left. Use thrust adjustments and rudder
tab to obtain this pattern. Proceed in
increments until maximum turns are reached.
Under full power, the model should climb in a
steep right corkscrew, with the nose pointed
up until just before the propeller folds. Motor
run should be roughly 50 seconds.
One advantage of the Moffett Rubber class
is that the duration potential of the model
exceeds the flight maximum unless down air
is encountered. Therefore, unlike a
contemporary Wakefield, it is not essential to
wind the motor to capacity on every flight.
Nor is a blast tube necessary unless you
choose to use one for safety purposes.
I normally wind the motor on my Moffett
800-850 turns, depending on the feel of the
rubber. Maximum capacity, by contrast, is
approximately 900 turns. Because of its
smooth texture, FAI Model Supply rubber is
normally resilient and unlikely to break unless
mistreated. On several occasions I have used
the same motor for all three competitive
flights.
If you are unwilling or unable to build your
Moffett Redux down to the structural weight
shown on the plans and the climb suffers
accordingly, I suggest an increase in power to
18 strands. One of the real joys of the Moffett
Rubber event is to watch your model climb to
an impressive height, which it may not do
unless thermal-assisted if underpowered.
Good luck with your Moffett Redux. MA
William Langenberg
3189 Danville Blvd., Suite 285
Alamo CA 94507
Sources:
Balsa and spruce wood:
Sig Manufacturing Company, Inc.
Box 520
Montezuma IA 50170
(641) 623-5154
Rubber, hardware, covering material:
FAI Model Supply
Box 366
Sayre PA 18840
(570) 882-9873
Propellers:
Superior Props
516 Driftwood Cir.
Slidell LA 70458
(985) 726-9673
October 2003 47
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.