100 MODEL AVIATION
HELLO SMALL-MODEL FANS! As I write this late in the month
of November, winter is creeping into Virginia and trimming down the
outside flying hours. For those of you fortunate enough to have
access to an indoor facility, at least you can keep on putting up
flights.
I have a situation I could use some feedback on. My Lithium-
Polymer (Li-Poly) cells seem to lose much of their capacity as the
temperature drops. Have you had that experience?
The last time I put a column together, I wrote about the National
Indoor Remote-controlled Aircraft Council (NIRAC) Championships
that will be held June 4-6, 2004, in Waterford, Michigan.
Because of space constraints, I left a couple of events to write
about this month. One of these is Indoor Electric Duration, event 627
in the AMA Competition Regulations. The battery allowed in this
event has been reduced to a four-50 mAh Ni-Cd-cell pack to reduce
flight times and give everyone more flying time. Since there are no
airframe restrictions in this event, the modeler is allowed to do his or
her own thing.
There are only a few ways to extend the flight of a model with
fixed, limited power. The wing loading can be reduced on a larger
model. On a cleaner model, another way is to reduce the drag.
Although this is an oversimplification, it is a valid starting point.
The models that have posted high times up until now have essentially
been enlarged Indoor Free Flight-style airframes with single-surface
covering, relatively wide-chord wings, and external rigging. This is
the low-wing loading approach, and it has worked well for several
prominent fliers.
I chose to go in another direction and reduce the drag while
keeping the weight to a minimum. The resulting model strongly
resembles the layout of many Outdoor Free Flight rubber-powered
endurance models. The long, slender wings keep the induced drag
low, and the clean, double-covered airfoil helps reduce drag even
more.
The test flying has been encouraging, with the potential for long
flights evident. The battery is fixed by the rules, but the other
equipment can be optimized. The DC5-2.4 motor has proven to be an
excellent choice for a blend between weight and efficiency.
Mating this motor to a smooth-running gear set is important as
well. The Didel gear trains and mounts available from Dynamic Web
Enterprises at www.smallrc.com are among the smoothest running
around.
Dynamic Web Enterprises also has a nice narrow-band,
lightweight receiver—the JMP—which will allow multiple models in
the air at the same time. I chose to use a light actuator for the rudder
(no elevator control is necessary) in the form of a 200-ohm Bird from
Cloud 9 Micro R/C models.
Why not break out the board and build something with which to
compete?
The Cargo event is one in which so far I have been a spectator.
The most successful models seem to have light construction with
fairly large wing chords and external rigging for support.
GWS IPS drives are the power of choice, and two Kokam 340
mAh cells provide the electricity. It is unnecessary to use equipment
with more capacity than the ability to trim the controls during the
flight. The lightest narrow-band gear would be desirable.
There is no question that large, free-rolling wheels on a rigid
landing gear can make the difference on those maximum-weight
takeoff efforts. The models from last year had single-surface wings,
but I have a strong feeling that they could be improved with good,
low-speed airfoils and double covering.
Dave Robelen
M i c r o - F l y i n g
Route 4, Box 369, Farmville VA 23901; E-mail: [email protected]
New micro hardware that comes from Gary Hutchison includes
the tiniest hinges the author has ever seen.
Jack Dobbins’ Sweetie came finished except for joining the wing
halves and mounting the tail.
The SHR PRO is a light receiver that has been available for
several years.
102 MODEL AVIATION
I think that external bracing would still
be the most practical choice. What do you
think? I bet there are some razor-sharp
designers who could lay out an efficient
airframe.
All of the event rules can be found at
www.nirac.org.
I have included pictures of my latest micro
fun: a WACO SRE. The wingspan is 14
inches, and it weighs 1 ounce. The controls
are my venerable RFFS-100 with push-pull
actuators and hardware by Gary Hutchison.
The drive is a KP-00 motor with 6:1 gearing
that powers a 5 x 4 propeller. Electricity
comes from one 230 mAh Li-Poly cell.
The significant part of this little project is
that it was built directly from Free Flight
Peanut Scale plans. I simply substituted 1⁄32
balsa for the stick-and-tissue original.
The little WACO is a delightful flier that
handles almost like a trainer. I was pleased
to note that it can handle some breeze
without being blown away. Watch for it at
www.rcmicroflight.com.
The WACO project brought out the
practical possibility of building these models
from the Free Flight plans using simple
material substitutions. There were many of
these plans (one every month) published in
the old Model Builder magazine. The
magazine is now out of circulation, but
original publisher Bill Northrop has been
offering packages of these plans for sale
through advertisements in Flying Models.
With the ability to resize any plans to this
range at a copy shop, the subjects are almost
limitless. Think in terms of 1⁄32 balsa-sheet
construction with single-surface, curvedwing
airfoils and flat-plate tails.
I am pleased with the results of using
automobile touch-up spray paint for a finish.
If possible, dilute this 50/50 with lacquer
thinner and apply with a simple airbrush.
The results add very little weight and really
brighten a model.
My old friend Jack Dobbins periodically
sends me another of his growing line of
prebuilt models. The most recent one is
called the Sweetie, and it came completely
finished except for joining the wing halves
and mounting the tail. All of the linkage and
control horns were premade and fit perfectly.
I mounted a GWS IPS A drive with a 9 x
7 propeller and used two Kokam 340 Li-
Poly cells for power. The controls I installed
were the Pico system from GWS, along with
the ICS-50 Electronic Speed Controller. As
you might expect, this aircraft is a real
“Sweetie” in the air. It has smooth controls
and no bad habits.
You can reach Jack by calling (309) 745-
8543 or writing to him at 402 Lotus Ln.,
Washington IL 61571. Jack told me that he
would be asking $50 shipped for one of
these gems.
Buy American and enjoy!
Several columns ago I mentioned a new
source of micro hardware from Gary
Hutchison in South Carolina. Besides
The long, slender wings of the author’s Microwatt endurance model keep the induced
drag low.
The author’s micro WACO SRE was built directly from Free Flight Peanut Scale plans.
misspelling Gary’s name (I apologize), he
sent a large variety of goodies to add to the
list after I sent the column out.
Along with the keepers and push-on
buttons, Gary has added some neat control
horns and actuator housing sets. There are
also some of the tiniest hinges I’ve ever seen!
You can purchase from Gary’s line
through Dynamic Web Enterprises at
www.smallrc.com. Tell ’em I sent you.
We seem to be on the threshold of a new
breakthrough in the ultra-light servo-driven
systems. The Cirrus line has been advertised
for a while and will probably be available
soon.
Didel company in France is producing a
servo that weighs less than 2 grams that is
available through www.smallrc.com. There is
a 1.7-gram gem called the Falcon on the way
from England and the CO2 expert Gasparin is
preparing to introduce a light servo. Most of
these feature magnetic Hall effect feedback
and are beautifully built.
It may not be common knowledge, but
there has been a light receiver available for
several years. This is the SHR PRO from Sky
Hooks and Rigging at www.microrc.com.
Although it is not especially narrow band, the
range is excellent and it is reliable. Mine has
served me well for quite awhile.
I am going to wrap this up. Remember, I
cannot show your projects if you do not send
me material. The same goes for
manufacturers. Many readers see this
column, and I will be glad to give you some
publicity if you send me the information. MA
Edition: Model Aviation - 2004/04
Page Numbers: 100,102
Edition: Model Aviation - 2004/04
Page Numbers: 100,102
100 MODEL AVIATION
HELLO SMALL-MODEL FANS! As I write this late in the month
of November, winter is creeping into Virginia and trimming down the
outside flying hours. For those of you fortunate enough to have
access to an indoor facility, at least you can keep on putting up
flights.
I have a situation I could use some feedback on. My Lithium-
Polymer (Li-Poly) cells seem to lose much of their capacity as the
temperature drops. Have you had that experience?
The last time I put a column together, I wrote about the National
Indoor Remote-controlled Aircraft Council (NIRAC) Championships
that will be held June 4-6, 2004, in Waterford, Michigan.
Because of space constraints, I left a couple of events to write
about this month. One of these is Indoor Electric Duration, event 627
in the AMA Competition Regulations. The battery allowed in this
event has been reduced to a four-50 mAh Ni-Cd-cell pack to reduce
flight times and give everyone more flying time. Since there are no
airframe restrictions in this event, the modeler is allowed to do his or
her own thing.
There are only a few ways to extend the flight of a model with
fixed, limited power. The wing loading can be reduced on a larger
model. On a cleaner model, another way is to reduce the drag.
Although this is an oversimplification, it is a valid starting point.
The models that have posted high times up until now have essentially
been enlarged Indoor Free Flight-style airframes with single-surface
covering, relatively wide-chord wings, and external rigging. This is
the low-wing loading approach, and it has worked well for several
prominent fliers.
I chose to go in another direction and reduce the drag while
keeping the weight to a minimum. The resulting model strongly
resembles the layout of many Outdoor Free Flight rubber-powered
endurance models. The long, slender wings keep the induced drag
low, and the clean, double-covered airfoil helps reduce drag even
more.
The test flying has been encouraging, with the potential for long
flights evident. The battery is fixed by the rules, but the other
equipment can be optimized. The DC5-2.4 motor has proven to be an
excellent choice for a blend between weight and efficiency.
Mating this motor to a smooth-running gear set is important as
well. The Didel gear trains and mounts available from Dynamic Web
Enterprises at www.smallrc.com are among the smoothest running
around.
Dynamic Web Enterprises also has a nice narrow-band,
lightweight receiver—the JMP—which will allow multiple models in
the air at the same time. I chose to use a light actuator for the rudder
(no elevator control is necessary) in the form of a 200-ohm Bird from
Cloud 9 Micro R/C models.
Why not break out the board and build something with which to
compete?
The Cargo event is one in which so far I have been a spectator.
The most successful models seem to have light construction with
fairly large wing chords and external rigging for support.
GWS IPS drives are the power of choice, and two Kokam 340
mAh cells provide the electricity. It is unnecessary to use equipment
with more capacity than the ability to trim the controls during the
flight. The lightest narrow-band gear would be desirable.
There is no question that large, free-rolling wheels on a rigid
landing gear can make the difference on those maximum-weight
takeoff efforts. The models from last year had single-surface wings,
but I have a strong feeling that they could be improved with good,
low-speed airfoils and double covering.
Dave Robelen
M i c r o - F l y i n g
Route 4, Box 369, Farmville VA 23901; E-mail: [email protected]
New micro hardware that comes from Gary Hutchison includes
the tiniest hinges the author has ever seen.
Jack Dobbins’ Sweetie came finished except for joining the wing
halves and mounting the tail.
The SHR PRO is a light receiver that has been available for
several years.
102 MODEL AVIATION
I think that external bracing would still
be the most practical choice. What do you
think? I bet there are some razor-sharp
designers who could lay out an efficient
airframe.
All of the event rules can be found at
www.nirac.org.
I have included pictures of my latest micro
fun: a WACO SRE. The wingspan is 14
inches, and it weighs 1 ounce. The controls
are my venerable RFFS-100 with push-pull
actuators and hardware by Gary Hutchison.
The drive is a KP-00 motor with 6:1 gearing
that powers a 5 x 4 propeller. Electricity
comes from one 230 mAh Li-Poly cell.
The significant part of this little project is
that it was built directly from Free Flight
Peanut Scale plans. I simply substituted 1⁄32
balsa for the stick-and-tissue original.
The little WACO is a delightful flier that
handles almost like a trainer. I was pleased
to note that it can handle some breeze
without being blown away. Watch for it at
www.rcmicroflight.com.
The WACO project brought out the
practical possibility of building these models
from the Free Flight plans using simple
material substitutions. There were many of
these plans (one every month) published in
the old Model Builder magazine. The
magazine is now out of circulation, but
original publisher Bill Northrop has been
offering packages of these plans for sale
through advertisements in Flying Models.
With the ability to resize any plans to this
range at a copy shop, the subjects are almost
limitless. Think in terms of 1⁄32 balsa-sheet
construction with single-surface, curvedwing
airfoils and flat-plate tails.
I am pleased with the results of using
automobile touch-up spray paint for a finish.
If possible, dilute this 50/50 with lacquer
thinner and apply with a simple airbrush.
The results add very little weight and really
brighten a model.
My old friend Jack Dobbins periodically
sends me another of his growing line of
prebuilt models. The most recent one is
called the Sweetie, and it came completely
finished except for joining the wing halves
and mounting the tail. All of the linkage and
control horns were premade and fit perfectly.
I mounted a GWS IPS A drive with a 9 x
7 propeller and used two Kokam 340 Li-
Poly cells for power. The controls I installed
were the Pico system from GWS, along with
the ICS-50 Electronic Speed Controller. As
you might expect, this aircraft is a real
“Sweetie” in the air. It has smooth controls
and no bad habits.
You can reach Jack by calling (309) 745-
8543 or writing to him at 402 Lotus Ln.,
Washington IL 61571. Jack told me that he
would be asking $50 shipped for one of
these gems.
Buy American and enjoy!
Several columns ago I mentioned a new
source of micro hardware from Gary
Hutchison in South Carolina. Besides
The long, slender wings of the author’s Microwatt endurance model keep the induced
drag low.
The author’s micro WACO SRE was built directly from Free Flight Peanut Scale plans.
misspelling Gary’s name (I apologize), he
sent a large variety of goodies to add to the
list after I sent the column out.
Along with the keepers and push-on
buttons, Gary has added some neat control
horns and actuator housing sets. There are
also some of the tiniest hinges I’ve ever seen!
You can purchase from Gary’s line
through Dynamic Web Enterprises at
www.smallrc.com. Tell ’em I sent you.
We seem to be on the threshold of a new
breakthrough in the ultra-light servo-driven
systems. The Cirrus line has been advertised
for a while and will probably be available
soon.
Didel company in France is producing a
servo that weighs less than 2 grams that is
available through www.smallrc.com. There is
a 1.7-gram gem called the Falcon on the way
from England and the CO2 expert Gasparin is
preparing to introduce a light servo. Most of
these feature magnetic Hall effect feedback
and are beautifully built.
It may not be common knowledge, but
there has been a light receiver available for
several years. This is the SHR PRO from Sky
Hooks and Rigging at www.microrc.com.
Although it is not especially narrow band, the
range is excellent and it is reliable. Mine has
served me well for quite awhile.
I am going to wrap this up. Remember, I
cannot show your projects if you do not send
me material. The same goes for
manufacturers. Many readers see this
column, and I will be glad to give you some
publicity if you send me the information. MA
