Product Review 2003/10

October 2003 87
THE RV-4 HAS long been a favorite of
those who like full-scale home-built aircraft.
It combines a sleek appearance, speed, and
aerobatic abilities in an affordable package.
Great Planes’ model of the RV-4 gives you
the same characteristics in a 40-size package.
This is a wood kit that requires
construction. Many of the main strength
parts are fashioned from three-ply light
plywood. The rest of the parts are made from
balsa of varying thicknesses. The balsa was
flat, but some of the plywood sheets were
bowed a bit.
One thing that struck me was that the
plywood and balsa parts are die-cut in this
day of laser-cutting. For the most part the die
cutting is clean and the corners are complete;
I did notice some pitting on the thicker
pieces. The usual die-cut cautions apply.
Great Planes is to be congratulated on
producing a fine set of plans sheets. The two
large sheets are detailed, accurate, and easy
to read. The construction manual is a fine
document; the discussion of the building
procedure is clearly written and easy to
follow. The detailed photos make the work
easy.
Follow the manual when constructing the
wing because the assembly is slightly
different. Pay particular attention to the
“TOP” notation on the wing shear web and
the wing trailing-edge pieces. I couldn’t see
it clearly on my kit parts, and it is important;
the dihedral is cut into these pieces for the
root rib.
The wing construction is interesting
because the shear web is inserted through
the ribs then rotated into position. The spars
then sit on top of the webbing. Even more
interesting is that you assemble all of the
spars, webbing, and ribs before gluing
Thomas Burdin
P r o d u c t R e v i e w
E-mail: [email protected]
Great Planes RV-4
Pros:
• Great plans
• Excellent manual
• Terrific hardware
• Fun to fly
Cons:
• Poor balsa consistency
• Plywood seemed soft.
• Parts did not always match plans or
other parts.
• Missing balsa strips
Below: Author finished RV-4 with MonoKote and LustreKote, with
beautiful results. It looks like it would fly well!
Right: This fairly short-coupled model has thin wing, so take care
at takeoff to prevent tip stall. Maintain airspeed!
88 MODEL AVIATION
Slightly exceeding the model’s recommended weight with the
Enya 46 engine did not seem problematic.
This nice first Sport Scale subject is docile enough for everyday
flying but aerobatic enough to be interesting.
This wood kit requires construction. Balsa and plywood parts are laser-cut for accuracy
and simplicity.
anything. Make sure that you lay the
assembly on the plans for accurate
orientation.
The manual calls for the use of
cyanoacrylate glue (CyA), and the diecutting
on these thinner pieces is mostly
accurate and clean, allowing you to use thin
CyA. However, you will need to use thicker
CyA to fill a few gaps.
The next step in the manual is to put on
the top and bottom sheeting. Instructions
recommend that you start with the upper
surface. The 5⁄32-inch sheeting varies in
stiffness, so choose the matching pieces for
this task. I found it easier to put the sheeting
on with the wing upside down on the plans.
I started gluing with CyA at the main
spar and slowly rolled the wing forward as I
attached the sheeting to the ribs. This slowly
bends the sheeting and keeps a flat surface.
The flatter bottom is then easy to do with
tape and slow-drying glue.
As I proceeded to the trailing-edge
sheeting, I found that the four 3⁄32 x 5⁄8 x 24-
inch strips were missing from the kit. I
purchased them from the local hobby shop.
The ailerons and flaps are an easy build;
they are constructed as a single piece that is
cut apart after construction. A 1⁄8 x 1⁄2-inch
sub-leading-edge strip was missing from the
kit.
Great Planes does a nice job of providing
hinge backup wood and a hardwood piece
for later attachment of the control horns.
The plans positioning of these hard-point
pieces for the ailerons is fine because the
control rods will come from opposite sides
of the servo arm to provide up-and-down
movement.
However, for the flaps, the servo arms
are incorrectly shown on opposite sides of
the servos. Do not mount your flap horns
and attachment hard points as shown on the
plans, or you will need a reversing “Y”
connector.
The wingtips are molded ABS plastic.
The manual calls for you to glue the final rib
into the ABS wingtip, then to glue the
assembly to the final wing rib. Getting that
rib glued inside the wingtip and assuring
that it is straight is a bear. I recommend that
you glue the rib to the end of the wing, then
carefully fit the tip to it. I substituted
Fiberglass Specialties fiberglass wingtips for
the supplied ABS material.
As I joined the wing halves, there was a
gap in the bottom surface joint. Either the
spar joiner or the die-cut angle on the spar
webbing was wrong, so I had to reduce the
dihedral to get the wing halves to match.
After preparing the doubled sides over
the plans and each other, the fuselage is
assembled upside-down on the middle deck.
When I started to place the die-cut formers
on the deck, I noticed that the rear former
did not fit per the plans. Later, when I was
adding the sides, the die-cut slots would not
allow the parts to align properly. Some
finagling was required to get the parts to fit.
In assembly of the two 1⁄8 plywood
firewall die-cut parts, there is some detail
that the manual does not explain. A 3° rightthrust
offset is built into the fuselage, so it is
necessary to offset the engine mount to the
left to center the propeller. The holes are
prepunched into the firewall pieces to do
this for you if you glue the firewall to the
fuselage correctly.
When you do, make sure that the holes
for the engine mount are offset to the left
side, or you may have the engine severely
off-centerline at the hub. The prepunched
holes are set up for the included Great
Planes engine mount.
As I finished installing the formers for
the turtleback and cowl area on the upper
deck, I added cross-grain bracing to all of
Photos courtesy the author
them. They are die cut from balsa and cut
with the grain horizontal. This makes them
susceptible to breakage as you roll on the top
3⁄32-inch sheeting.
The front and rear cockpit formers are
installed on an angle. There is no guide in the
kit for the amount of slope, and installation
leaves them floating on the deck with only
the edge glue for support as you try to add
the 3⁄32-inch wraparound sheeting. I devised
some angle braces for them from leftover
plywood. The angle on the rear cockpit is 5°
from the vertical and 19° for the instrument
panel as measured from the plans.
The fuselage features a nice tank hatch on
the top of the engine mount. However, I had
to create a new hatch cover because the diecut
part provided did not fit into the tabs and
slots.
Even though it’s shown on the plans, the
manual mentions nothing about doubling for
the servo-mount area in the middle deck, but
wood is provided. Use scrap plywood and
double the aileron/flap fixtures too.
The fuselage sides have precise slots cut
into them for installation of the pushrod
guide tubes. However, you will have to bevel
the pushrods with a 1⁄4-inch rat-tail file so
that the tubes will have a smooth line of
travel. This will prevent serious binding of
the provided steel pushrods.
I used fiberglass wheel pants and added
some toe-in to the wheel alignment. I beefed
up the tail-wheel system by adding a 1 x 3⁄32-
inch-outside-diameter brass tube in the
rudder where the steering dog enters the
rudder to prevent chafing of the hole.
I installed the engine at the instructed
distance from the firewall to the thrust
washer. I am a bit fussy about using datum
lines and measuring a great deal when I fit
my models’ cowls. Measure twice and cut
once.
I learned that the supplied ABS cowl and
my fiberglass cowl were each approximately
3⁄4 inch longer than the plans indicated. If I
lined up the rear of the cowl on the datum
lines indicated on the plans, the drive washer
on the engine would be roughly 3⁄4 inch
behind the front of the cowl. If I pushed the
cowl on until the propeller washer emerged,
the bottom of the cowl would extend over the
landing gear.
The simple solution is to trim the cowl to
match your needs. I wish Great Planes would
change the cowl so it matches the plans or
modify the instructions to include trimming
directions.
The kit provides lightening holes in the
fuselage sides. However, when you add the
cowl you will find that its pointed end rests
right over the forward hole, which makes it
susceptible to puncturing and tearing the
covering material. I filled in the front hole
with a piece of scrap plywood so that the end
of the cowl lays over a hard surface.
As with the wingtips, I replaced the
provided ABS cowl with a fiberglass
version. Both have the right-thrust offset
built into their shapes so that the spinner fits
squarely. Final finishing was with MonoKote
and LustreKote.
After easily installing the radio, the finished
model came out at 63⁄4 pounds, which
slightly exceeds the 61⁄4 pounds predicted on
the kit. Since I was using my trusty Enya 46
II four-stroke engine, the nose weight was
increased.
Had I used the recommended O.S. 70
four-stroke, it would have been even more of
a problem. The fiberglass cowl, wingtips,
and wheel pants added their share of weight
too. To balance the model as required, I
strapped the battery pack to the wing
mounting plate.
Ground handling was good, with no bad
characteristics. I could not delay anymore
with everyone watching, so I went for the
gold. Takeoff tracking was clean and
controllable. The tail came right up and the
aircraft lifted off with minimum up-elevator.
I had some left turn to trim out but
wanted some altitude before I did that. Don’t
be tempted to have more elevator throw than
recommended; you don’t need it. Aileron
control was fine per the plans.
I ran through the usual Rolls, Loops, and
Clover Leafs, and I found that the RV-4 was
nice to fly. I lowered the flaps for slow flight
to see what it would do. Slow flight was easy
and the model controlled effortlessly.
My old Enya pulled the airplane around
easily. The slight increase in weight from
what was recommended did not seem to be a
problem. I don’t think you really need a 70
four-stroke. A .45-.50 two-stroke sounds
right, and you should use no larger than a 53
four-stroke.
The RV-4 Snap Rolls as you would
expect a thin-winged, short-coupled model to
do. The increase in weight may have added a
little sensitivity here. I did a 360° overhead
pattern and pulled the power to idle on the
pitch out. I added no power the whole way
around. The model floated onto the runway
with ease.
I used flaps on the second landing, but I
did not notice any appreciable difference in
the landing except for the need for a little
power on final, as you might expect. This is a
9 Unleash the power of
Irvine’s new 39 series engines deliver
maximum power – minimum weight
39 Aero ABC Engine w/muffler
Bore: 0.84 inches
Stroke: 0.71 inches
Weight w/muffler: 13.6 ounces
RPM Range: 2,800 - 18,000 rpm
Horsepower: 1.3 bhp @ 18,000 rpm
Item#IRV4391
39 Heli ABC Engine w/muffler
Bore: 0.84 inches
Stroke: 0.71 inches
Weight w/muffler: 10.6 ounces
RPM Range: 3,000 - 22,000 rpm
Horsepower: 1.4 bhp @ 20,000 rpm
Item#IRV4393
Flying may never be the same.
Irvine breaks new ground with their high performance .39 cubic inch glow engines for R/C
airplanes and helicopters. Using state-of-the-art engineering and metalrurgy, these new .39’s create
more power than conventional .40’s, yet in a size and weight compared to some .30’s.
The Aero .39 tips the horsepower scale at an amazing 1.3 bhp at 18,000 rpm while weighing only
13-1/2 ounces with muffler.
The Heli .39 rocks the world with an outstanding 1.4 bhp at 20,000 rpm, yet weighs less than 11
ounces ready to mount in most .30-size R/C helicopters.
Unleash the power of 9 in your airplane or helicopter. Feel how a smaller engine can perform.
Irvine Engines is distributed exclusively by:
SIG Manufacturing Company, Inc.
P.O. Box 520
Montezuma, Iowa 50171-0520
Visit our web site: www.sigmfg.com
very nice stand-off-scale sport model. It is a
fun fly despite the construction difficulties.
This Great Planes offering has the potential to
be a wonderful kit. The RV-4 is a great aircraft,
and the kit represents some fine ideas.
However, the company needs to be more
careful in the selection of materials and
accuracy of the die-cutting and assuring that
parts fit correctly.
The three-ply plywood is soft, and the balsa
does not match in hardness. It appears that
nobody at Great Planes built the aircraft from a
production offering, or that person would have
found the problems I found.
Great Planes, please don’t stamp the part
numbers into the materials. Some of those
stamped identifiers wind up on the exterior
surfaces of the aircraft and require more filling
to provide a good finish. The manual shows all
of the die-cut sheets, and parts identification is
simple from the diagrams. MA
Note from Great Planes: The RV-4 kit used
in this review came off of the first production
run in early 2002. All of the concerns this
reviewer expressed have since been addressed
and corrected.
Please note that the cowl, wingtips, etc.
were supplied to the reviewer by a third-party
vendor and, although similar in size and shape,
did not provide the fit you can expect from the
Great Planes parts supplied with the kit.
Manufacturer/Distributor
Fiberglass cowl, wingtips, wheel pants:
Fiberglass Specialties, Inc.
Box 1340
Henderson TX 75652
(800) 527-1459
www.fiberglassspecialties.com/
MonoKote/LustreKote finishing products:
Great Planes Model Manufacturing
Company
www.monokote.com/
October 2003 95
Great Planes Model Manufacturing Company
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com/airplanes/gpma0180.html
Specifications:
Model type: Ready-to-build kit
Wingspan: 54.65 inches
Wing area: 631.60 square inches
Length: 49.60 inches
Recommended weight: 5.75-6.25 pounds
Review model (ready to fly): 6.75 pounds
Recommended engine: .40-.52 two-stroke or
48-70 four-stroke
Engine used: Enya 46 II four-stroke
Recommended radio: four- to five-channel,
five to seven servos
Radio used: JR 8103 transmitter, receiver,
and seven NES517 servos
Materials used in construction: Balsa,
plywood, ABS cowl, wheel pants
Stock number: GPMA0180
Street price: $99.99
Products used in review:
JR 8103 radio system:
Horizon Hobby Distributors
4105 Fieldstone Rd.
Champaign IL 61822
(217) 352-1913
http://horizon.hobbyshopnow.com/products/
jr.asp
Enya 46 engine:
Model Rectifier Corporation
Box 6312
Edison NJ 08818
(732) 225-2100
www.modelrectifier.com/catalog/item91.html
Order online:
www.airbornemedia.com
Call Toll Free:
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$275 8CH. TX AND RX
SYNTHESIZED DIAL A FREQUENCY
1024 stick steps for digital servo performance w/o
the cost. 40mhz chip. 99 model memory. scanner
built in. 3 - 2 way mixes & EZ programming
SEEKER RX also sold separately $70 WORKS
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Irvington, NJ 07111
973-351-9800 FAX 9700
www.polkshobby.com
DEALER INQ.
INVITED
w/chgr.,900 m.a.
nicads, 1 servo

October 2003 87
THE RV-4 HAS long been a favorite of
those who like full-scale home-built aircraft.
It combines a sleek appearance, speed, and
aerobatic abilities in an affordable package.
Great Planes’ model of the RV-4 gives you
the same characteristics in a 40-size package.
This is a wood kit that requires
construction. Many of the main strength
parts are fashioned from three-ply light
plywood. The rest of the parts are made from
balsa of varying thicknesses. The balsa was
flat, but some of the plywood sheets were
bowed a bit.
One thing that struck me was that the
plywood and balsa parts are die-cut in this
day of laser-cutting. For the most part the die
cutting is clean and the corners are complete;
I did notice some pitting on the thicker
pieces. The usual die-cut cautions apply.
Great Planes is to be congratulated on
producing a fine set of plans sheets. The two
large sheets are detailed, accurate, and easy
to read. The construction manual is a fine
document; the discussion of the building
procedure is clearly written and easy to
follow. The detailed photos make the work
easy.
Follow the manual when constructing the
wing because the assembly is slightly
different. Pay particular attention to the
“TOP” notation on the wing shear web and
the wing trailing-edge pieces. I couldn’t see
it clearly on my kit parts, and it is important;
the dihedral is cut into these pieces for the
root rib.
The wing construction is interesting
because the shear web is inserted through
the ribs then rotated into position. The spars
then sit on top of the webbing. Even more
interesting is that you assemble all of the
spars, webbing, and ribs before gluing
Thomas Burdin
P r o d u c t R e v i e w
E-mail: [email protected]
Great Planes RV-4
Pros:
• Great plans
• Excellent manual
• Terrific hardware
• Fun to fly
Cons:
• Poor balsa consistency
• Plywood seemed soft.
• Parts did not always match plans or
other parts.
• Missing balsa strips
Below: Author finished RV-4 with MonoKote and LustreKote, with
beautiful results. It looks like it would fly well!
Right: This fairly short-coupled model has thin wing, so take care
at takeoff to prevent tip stall. Maintain airspeed!
88 MODEL AVIATION
Slightly exceeding the model’s recommended weight with the
Enya 46 engine did not seem problematic.
This nice first Sport Scale subject is docile enough for everyday
flying but aerobatic enough to be interesting.
This wood kit requires construction. Balsa and plywood parts are laser-cut for accuracy
and simplicity.
anything. Make sure that you lay the
assembly on the plans for accurate
orientation.
The manual calls for the use of
cyanoacrylate glue (CyA), and the diecutting
on these thinner pieces is mostly
accurate and clean, allowing you to use thin
CyA. However, you will need to use thicker
CyA to fill a few gaps.
The next step in the manual is to put on
the top and bottom sheeting. Instructions
recommend that you start with the upper
surface. The 5⁄32-inch sheeting varies in
stiffness, so choose the matching pieces for
this task. I found it easier to put the sheeting
on with the wing upside down on the plans.
I started gluing with CyA at the main
spar and slowly rolled the wing forward as I
attached the sheeting to the ribs. This slowly
bends the sheeting and keeps a flat surface.
The flatter bottom is then easy to do with
tape and slow-drying glue.
As I proceeded to the trailing-edge
sheeting, I found that the four 3⁄32 x 5⁄8 x 24-
inch strips were missing from the kit. I
purchased them from the local hobby shop.
The ailerons and flaps are an easy build;
they are constructed as a single piece that is
cut apart after construction. A 1⁄8 x 1⁄2-inch
sub-leading-edge strip was missing from the
kit.
Great Planes does a nice job of providing
hinge backup wood and a hardwood piece
for later attachment of the control horns.
The plans positioning of these hard-point
pieces for the ailerons is fine because the
control rods will come from opposite sides
of the servo arm to provide up-and-down
movement.
However, for the flaps, the servo arms
are incorrectly shown on opposite sides of
the servos. Do not mount your flap horns
and attachment hard points as shown on the
plans, or you will need a reversing “Y”
connector.
The wingtips are molded ABS plastic.
The manual calls for you to glue the final rib
into the ABS wingtip, then to glue the
assembly to the final wing rib. Getting that
rib glued inside the wingtip and assuring
that it is straight is a bear. I recommend that
you glue the rib to the end of the wing, then
carefully fit the tip to it. I substituted
Fiberglass Specialties fiberglass wingtips for
the supplied ABS material.
As I joined the wing halves, there was a
gap in the bottom surface joint. Either the
spar joiner or the die-cut angle on the spar
webbing was wrong, so I had to reduce the
dihedral to get the wing halves to match.
After preparing the doubled sides over
the plans and each other, the fuselage is
assembled upside-down on the middle deck.
When I started to place the die-cut formers
on the deck, I noticed that the rear former
did not fit per the plans. Later, when I was
adding the sides, the die-cut slots would not
allow the parts to align properly. Some
finagling was required to get the parts to fit.
In assembly of the two 1⁄8 plywood
firewall die-cut parts, there is some detail
that the manual does not explain. A 3° rightthrust
offset is built into the fuselage, so it is
necessary to offset the engine mount to the
left to center the propeller. The holes are
prepunched into the firewall pieces to do
this for you if you glue the firewall to the
fuselage correctly.
When you do, make sure that the holes
for the engine mount are offset to the left
side, or you may have the engine severely
off-centerline at the hub. The prepunched
holes are set up for the included Great
Planes engine mount.
As I finished installing the formers for
the turtleback and cowl area on the upper
deck, I added cross-grain bracing to all of
Photos courtesy the author
them. They are die cut from balsa and cut
with the grain horizontal. This makes them
susceptible to breakage as you roll on the top
3⁄32-inch sheeting.
The front and rear cockpit formers are
installed on an angle. There is no guide in the
kit for the amount of slope, and installation
leaves them floating on the deck with only
the edge glue for support as you try to add
the 3⁄32-inch wraparound sheeting. I devised
some angle braces for them from leftover
plywood. The angle on the rear cockpit is 5°
from the vertical and 19° for the instrument
panel as measured from the plans.
The fuselage features a nice tank hatch on
the top of the engine mount. However, I had
to create a new hatch cover because the diecut
part provided did not fit into the tabs and
slots.
Even though it’s shown on the plans, the
manual mentions nothing about doubling for
the servo-mount area in the middle deck, but
wood is provided. Use scrap plywood and
double the aileron/flap fixtures too.
The fuselage sides have precise slots cut
into them for installation of the pushrod
guide tubes. However, you will have to bevel
the pushrods with a 1⁄4-inch rat-tail file so
that the tubes will have a smooth line of
travel. This will prevent serious binding of
the provided steel pushrods.
I used fiberglass wheel pants and added
some toe-in to the wheel alignment. I beefed
up the tail-wheel system by adding a 1 x 3⁄32-
inch-outside-diameter brass tube in the
rudder where the steering dog enters the
rudder to prevent chafing of the hole.
I installed the engine at the instructed
distance from the firewall to the thrust
washer. I am a bit fussy about using datum
lines and measuring a great deal when I fit
my models’ cowls. Measure twice and cut
once.
I learned that the supplied ABS cowl and
my fiberglass cowl were each approximately
3⁄4 inch longer than the plans indicated. If I
lined up the rear of the cowl on the datum
lines indicated on the plans, the drive washer
on the engine would be roughly 3⁄4 inch
behind the front of the cowl. If I pushed the
cowl on until the propeller washer emerged,
the bottom of the cowl would extend over the
landing gear.
The simple solution is to trim the cowl to
match your needs. I wish Great Planes would
change the cowl so it matches the plans or
modify the instructions to include trimming
directions.
The kit provides lightening holes in the
fuselage sides. However, when you add the
cowl you will find that its pointed end rests
right over the forward hole, which makes it
susceptible to puncturing and tearing the
covering material. I filled in the front hole
with a piece of scrap plywood so that the end
of the cowl lays over a hard surface.
As with the wingtips, I replaced the
provided ABS cowl with a fiberglass
version. Both have the right-thrust offset
built into their shapes so that the spinner fits
squarely. Final finishing was with MonoKote
and LustreKote.
After easily installing the radio, the finished
model came out at 63⁄4 pounds, which
slightly exceeds the 61⁄4 pounds predicted on
the kit. Since I was using my trusty Enya 46
II four-stroke engine, the nose weight was
increased.
Had I used the recommended O.S. 70
four-stroke, it would have been even more of
a problem. The fiberglass cowl, wingtips,
and wheel pants added their share of weight
too. To balance the model as required, I
strapped the battery pack to the wing
mounting plate.
Ground handling was good, with no bad
characteristics. I could not delay anymore
with everyone watching, so I went for the
gold. Takeoff tracking was clean and
controllable. The tail came right up and the
aircraft lifted off with minimum up-elevator.
I had some left turn to trim out but
wanted some altitude before I did that. Don’t
be tempted to have more elevator throw than
recommended; you don’t need it. Aileron
control was fine per the plans.
I ran through the usual Rolls, Loops, and
Clover Leafs, and I found that the RV-4 was
nice to fly. I lowered the flaps for slow flight
to see what it would do. Slow flight was easy
and the model controlled effortlessly.
My old Enya pulled the airplane around
easily. The slight increase in weight from
what was recommended did not seem to be a
problem. I don’t think you really need a 70
four-stroke. A .45-.50 two-stroke sounds
right, and you should use no larger than a 53
four-stroke.
The RV-4 Snap Rolls as you would
expect a thin-winged, short-coupled model to
do. The increase in weight may have added a
little sensitivity here. I did a 360° overhead
pattern and pulled the power to idle on the
pitch out. I added no power the whole way
around. The model floated onto the runway
with ease.
I used flaps on the second landing, but I
did not notice any appreciable difference in
the landing except for the need for a little
power on final, as you might expect. This is a
9 Unleash the power of
Irvine’s new 39 series engines deliver
maximum power – minimum weight
39 Aero ABC Engine w/muffler
Bore: 0.84 inches
Stroke: 0.71 inches
Weight w/muffler: 13.6 ounces
RPM Range: 2,800 - 18,000 rpm
Horsepower: 1.3 bhp @ 18,000 rpm
Item#IRV4391
39 Heli ABC Engine w/muffler
Bore: 0.84 inches
Stroke: 0.71 inches
Weight w/muffler: 10.6 ounces
RPM Range: 3,000 - 22,000 rpm
Horsepower: 1.4 bhp @ 20,000 rpm
Item#IRV4393
Flying may never be the same.
Irvine breaks new ground with their high performance .39 cubic inch glow engines for R/C
airplanes and helicopters. Using state-of-the-art engineering and metalrurgy, these new .39’s create
more power than conventional .40’s, yet in a size and weight compared to some .30’s.
The Aero .39 tips the horsepower scale at an amazing 1.3 bhp at 18,000 rpm while weighing only
13-1/2 ounces with muffler.
The Heli .39 rocks the world with an outstanding 1.4 bhp at 20,000 rpm, yet weighs less than 11
ounces ready to mount in most .30-size R/C helicopters.
Unleash the power of 9 in your airplane or helicopter. Feel how a smaller engine can perform.
Irvine Engines is distributed exclusively by:
SIG Manufacturing Company, Inc.
P.O. Box 520
Montezuma, Iowa 50171-0520
Visit our web site: www.sigmfg.com
very nice stand-off-scale sport model. It is a
fun fly despite the construction difficulties.
This Great Planes offering has the potential to
be a wonderful kit. The RV-4 is a great aircraft,
and the kit represents some fine ideas.
However, the company needs to be more
careful in the selection of materials and
accuracy of the die-cutting and assuring that
parts fit correctly.
The three-ply plywood is soft, and the balsa
does not match in hardness. It appears that
nobody at Great Planes built the aircraft from a
production offering, or that person would have
found the problems I found.
Great Planes, please don’t stamp the part
numbers into the materials. Some of those
stamped identifiers wind up on the exterior
surfaces of the aircraft and require more filling
to provide a good finish. The manual shows all
of the die-cut sheets, and parts identification is
simple from the diagrams. MA
Note from Great Planes: The RV-4 kit used
in this review came off of the first production
run in early 2002. All of the concerns this
reviewer expressed have since been addressed
and corrected.
Please note that the cowl, wingtips, etc.
were supplied to the reviewer by a third-party
vendor and, although similar in size and shape,
did not provide the fit you can expect from the
Great Planes parts supplied with the kit.
Manufacturer/Distributor
Fiberglass cowl, wingtips, wheel pants:
Fiberglass Specialties, Inc.
Box 1340
Henderson TX 75652
(800) 527-1459
www.fiberglassspecialties.com/
MonoKote/LustreKote finishing products:
Great Planes Model Manufacturing
Company
www.monokote.com/
October 2003 95
Great Planes Model Manufacturing Company
Box 9021
Champaign IL 61826
(217) 398-8970
www.greatplanes.com/airplanes/gpma0180.html
Specifications:
Model type: Ready-to-build kit
Wingspan: 54.65 inches
Wing area: 631.60 square inches
Length: 49.60 inches
Recommended weight: 5.75-6.25 pounds
Review model (ready to fly): 6.75 pounds
Recommended engine: .40-.52 two-stroke or
48-70 four-stroke
Engine used: Enya 46 II four-stroke
Recommended radio: four- to five-channel,
five to seven servos
Radio used: JR 8103 transmitter, receiver,
and seven NES517 servos
Materials used in construction: Balsa,
plywood, ABS cowl, wheel pants
Stock number: GPMA0180
Street price: $99.99
Products used in review:
JR 8103 radio system:
Horizon Hobby Distributors
4105 Fieldstone Rd.
Champaign IL 61822
(217) 352-1913
http://horizon.hobbyshopnow.com/products/
jr.asp
Enya 46 engine:
Model Rectifier Corporation
Box 6312
Edison NJ 08818
(732) 225-2100
www.modelrectifier.com/catalog/item91.html
Order online:
www.airbornemedia.com
Call Toll Free:
888-829-4060
16x20- only $1495
24x36- only $1995
Please add $500 postage/handing for a single poster; $150 extra for each additional poster.
Cover of 08/03 Model Aviation
• Available in 16x20
and 24x36 sizes
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glossy paper
• Shipped rolled, in
tubes for protection.
• Perfect way to dress
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© 2003, Airborne Media. All Rights Reserved.
Fine Art
To Dress Up
Any Shop.
TRACKER II 8 CH DIGITAL R/C FM
NO MORE CRYSTALS!
ANY OTHER WAY IS OUT OF DATE!
$275 8CH. TX AND RX
SYNTHESIZED DIAL A FREQUENCY
1024 stick steps for digital servo performance w/o
the cost. 40mhz chip. 99 model memory. scanner
built in. 3 - 2 way mixes & EZ programming
SEEKER RX also sold separately $70 WORKS
W / ANY FM TX w/o need for crystal
698 S. 21st Street
Irvington, NJ 07111
973-351-9800 FAX 9700
www.polkshobby.com
DEALER INQ.
INVITED
w/chgr.,900 m.a.
nicads, 1 servo