Q245: “I’ve read so much lately on the
subject of balancing the cells within a Li-Poly
battery pack. That the term ‘balancing’ refers
to the condition when all cells in the pack
have the same voltage.
“But I also hear that it is important to
monitor these same cells while they are being
discharged in flight. What’s the story on this
and what should I be doing to make this
happen?”
A245: You bring up an interesting point. Just
making sure the cells within your Li-Poly
battery are balanced (all have the same
voltage) takes into account only part of the
possible problem. Starting with all cells at the
same voltage doesn’t necessarily mean all
those cells will hit the same minimum cutoff
voltage at the end of a flight.
The capacity of each cell in a pack will
determine how fast it gets to some minimum
value, such as 3.0 volts. Depending on the
capacity, some cells will get to that level
before others.
FMA Direct offers an onboard monitoring device for Li-Poly batteries
September 2006 101
? Frequently Asked Questions Bob Aberle | [email protected]
Also included in this column:
• Intro to indoor/micro RC
• Transmitter-stick-length extenders
• Field kit battery voltage monitor
• RC Skydiving
• SR Batteries’ gapless hinge material
Scott Christensen’s tiny Yardsail is a typical indoor/micro RC model that weighs less
than an ounce ready to fly with an RC system, motor, and battery.
The author’s Scratch-65: a 2.6-ounce design featured in a
construction article with plans in the February 2005 MA.
The new in-flight Li-Poly cell voltage-monitoring device called
the MM7 will soon be offered by SLK Electronics.
THIS IS THE 30th monthly column in which
I try to give you the best possible answers to
questions you have written or E-mailed to me.
Each new question is given a sequential
number for identification purposes.
Until now this column has appeared in the
pages of MA and additional questions and
answers have been posted on a special section
of the AMA Web site (www.modelair
craft.org). That Web page is now in the process
of being revised and, as such, there will be no
new postings in the foreseeable future.
What you read each month in print is
all you will see. I will advise you when we
are able to return to the original format.
The original “search process” by
categories will also be suspended until the
posting is back online.
In the meantime, I’m available to help
you locate specific subjects of interest. Just
drop me an E-mail. Also please keep
sending in your questions; that’s the only
way I can continue to provide this service
to readers.
09sig4.QXD 7/25/06 2:11 PM Page 101102 MODEL AVIATION
Hobby Lobby’s 3.5-ounce Graupner Mosquito is a typical micro indoor model sold as a kit.
It uses a Speed 250 motor and three 250 mAh Li Poly battery cells. It spans 22 inches.
If you have ever gotten to your flying field only to find your 12-volt field kit battery
dead, the VoltWatch monitoring device by Hobbico is for you.
Bob’s favorite hinge material is SR Batteries’ clear Gapless Hinge Tape. It is sold in
lengths that can be cut to suit the size of your particular models.
For those who use transmitter supporting
trays, 3D Hobby Shop’s “BigStik”
control-stick extensions provide a much
better “feel of flying.”
burp (turn on and off quickly), alerting you to
land as soon as possible.
By using this DPM, no cell in the pack
will ever go below the recommended
minimum voltage. This discharge technique,
along with balanced charging at
approximately a 1C current rate, will add
tremendously to the life of—and safe use
of—your Li-Poly battery packs.
While writing this answer I learned, to my
pleasant surprise, that Sid Kauffman—the
creator of the ElectriCalc motor-selection
program—has just developed his own
protection module, which he calls the MM7
In-Flight Cell Monitor.
This onboard device can handle packs
with two to seven Li-Poly cells. It weighs just
10 grams (0.35 ounce) and is expected to sell
for roughly $40 including shipping. The
MM7 is simple to hook up in your aircraft
and to set up. Best of all, it will plug into
most popular (individual cell wired) Li-Poly
Most modern ESCs, set up for use with
Li-Poly batteries, monitor the total pack
voltage down to something such as 3.0 volts
per cell. Therefore, a three-cell pack might be
cut off when the total of three-cell voltage
reaches 9.0. But as I just explained, it is
possible that one of the cells has gone
significantly lower than 3.0 volts while the
other two were actually higher than that.
If you were using a balancing charger,
such as the FMA Direct BalancePro HD or
Cellpro 4S, the cells would all be rebalanced
at the completion of the next charge.
However, if you are using an ordinary
charger that does not charge each cell
separately, you will have a battery pack that
is clearly out of balance and heading for rapid
deterioration.
The solution to this problem of
discharging Li-Poly batteries is to use a new
onboard monitoring device called a
Discharge Protection Module (DPM). FMA
Direct now sells DPMs for use with both of
their balancing systems (BalancePro HD and
Cellpro 4S).
Since FMA Direct’s special battery packs
are wired with access to the individual cell, it
is easy to monitor each cell in flight. When
the first cell hits 3.0 volts your motor will
09sig4.QXD 7/26/06 9:16 AM Page 102battery packs on the market, including
Thunder Power, Poly-Quest, Duralite, and
Hobby Lobby “Twenty.”
Standard mating connectors will be
available for five-pin (two to four cells) and
eight-pin (two to seven cells) battery packs.
The MM7 should be available by the time
you read this. Go to
www.slkelectronics.com for more
information.
Q246: “I consider myself an average RC
sport flier. I live in an area of our country
where winter weather makes it impossible
for me to fly. But I keep hearing all these
good things about flying indoors in gyms,
school auditoriums, and even inflatable
sports domes. How does one learn about
indoor RC flying?”
A246: I mentioned awhile ago that former
AMA Executive Director John Worth had
started his own webzine (Internet-oriented
magazine) called RC Micro World. This
“publication” is posted monthly to a secure
Web site you access by paying a
subscription fee.
To help John promote his specialized
publication, I recently prepared a guidetype
document I call the “Intro to
Indoor/Micro RC.” It was written with the
assumption that you already know
something about RC flying. But then it goes
on to cover all the details necessary to
build, assemble, and fly RC models at
indoor facilities.
This guide is available on a special free
portion of John’s Web page at www.cloud9
rc.com/indoorflying.asp. I urge you to look
at it because it will answer most of your
questions concerning getting started in
indoor RC flying.
Q247: “I’ve seen transmitter supporting
trays with a strap that goes around your
neck. Once supported, the need for
transmitter control-stick extensions
becomes obvious. Can you lead me to a
source of supply for extended-length
control sticks?”
A247: After a little searching I found 3D
Hobby Shop’s Web site at www.3dhobby
shop.com/detail.aspx?ID=993. It offers
modular aluminum transmitter-control-stick
extensions under the trade name “BigStix.”
One set is intended for JR and Spektrum
owners, and the other is for the Hitec or
Futaba transmitter owner. Each set sells for
$24.99. I found some other electric 3-D
accessory products on this Web page that
may interest many RC pilots.
Q248: “I’ve experienced a situation of
arriving at my flying field after a long drive
only to find out that my 12-volt field kit
battery is dead. Is there any kind of voltagemonitoring
device available?”
A248: Hobbico has a 12-volt batterymonitoring
device called the VoltWatch. It is
catalog item HCAP0331 and presently sells
for $9.99. You can find it at www.hobbico
.com/fieldequip/hcap0331.html.
This unit uses multicolored LEDs to let
you know the voltage range from 11.0 to
13.0 volts. It can be mounted to the outside
of your field kit box using double-stick tape.
Just make sure you press the “ON” test
button before taking off for your flying field.
Q249: “I had heard that a company is now
offering a radio-control skydiver which can
be dropped from an RC aircraft. I haven’t
seen it advertised as yet and was wondering
if you might direct me to the Web site.”
A249: I found a company that appears to
specialize in RC skydiving products. The
Web site is http://rcskydiving.com/
store/index.php?act=viewCat&catId=3. I
haven’t seen any of these products yet, but
the description on the Web page is thorough.
The site offers Micro Diver, which
consists of a 9-inch figure and a suitable
parachute; the total weight is 10 ounces. The
“diver” requires two microservos, a receiver,
and a four-cell battery pack.
The diver is carried aloft with an RC
model aircraft and then released at altitude.
A static line will open the chute on release.
Then a second pilot flies the diver down for a
landing.
This is only an announcement of the
product. I urge you to see the Web page for
more detailed information.
Q250: “I have noted in many of your
product reviews and construction articles
that you seem to favor the Gapless Hinge
Tape as sold by SR Batteries, Inc. What
made you so sold on this particular
product?”
A250: I was first introduced to this gapless
hinge material in 2002 when I was
reviewing the SR Batteries Bantam
monoplane and biplane park flyers. The
tape was supplied with both kits, which
were designed by SR Batteries owner
Larry Sribnick.
The tape was originally manufactured
by the 3M company. It is approximately 1
inch in width and is clear, with a sticky
cement applied to one side. SR Batteries
provides an excellent application sheet
along with the hinge material.
The installation technique is simple.
You line up the flying surface and control
surface (such as a stabilizer and elevator),
establishing a suitable spacing, and then
anchor the two surfaces with several pieces
of masking tape.
Peel off the protective backing on the
hinge tape, and apply it so that an equal
amount is on the flying surface and the
control surface. Press it down firmly to
make a solid contact, then remove the
masking tape. You will find the hinged
surface smooth and without gaps.
Because of the clear tape, you can
cover or paint your aircraft surfaces before
applying the tape. One thing you must be
aware of is that the cement used on this
tape is not fuelproof. Thus you can’t use
this material on a fuel-powered aircraft.
However, it is perfect for electric-powered
models and sailplanes.
I use the Gapless Hinge Tape on almost
all my aircraft. The only exception might
be a rudder that has a steerable tail wheel
at the lower extremity. That application
generally works better with a “Lite” hinge
or a molded-nylon hinge with a metal pin.
You can obtain the Gapless Hinge Tape
from SR Batteries Inc., Box 287, Bellport
NY 11713; Tel.: (631) 286-0079; Web
site: www.srbatteries.com.
That’s a wrap for this month! MA
Edition: Model Aviation - 2006/09
Page Numbers: 101,102,104
Edition: Model Aviation - 2006/09
Page Numbers: 101,102,104
Q245: “I’ve read so much lately on the
subject of balancing the cells within a Li-Poly
battery pack. That the term ‘balancing’ refers
to the condition when all cells in the pack
have the same voltage.
“But I also hear that it is important to
monitor these same cells while they are being
discharged in flight. What’s the story on this
and what should I be doing to make this
happen?”
A245: You bring up an interesting point. Just
making sure the cells within your Li-Poly
battery are balanced (all have the same
voltage) takes into account only part of the
possible problem. Starting with all cells at the
same voltage doesn’t necessarily mean all
those cells will hit the same minimum cutoff
voltage at the end of a flight.
The capacity of each cell in a pack will
determine how fast it gets to some minimum
value, such as 3.0 volts. Depending on the
capacity, some cells will get to that level
before others.
FMA Direct offers an onboard monitoring device for Li-Poly batteries
September 2006 101
? Frequently Asked Questions Bob Aberle | [email protected]
Also included in this column:
• Intro to indoor/micro RC
• Transmitter-stick-length extenders
• Field kit battery voltage monitor
• RC Skydiving
• SR Batteries’ gapless hinge material
Scott Christensen’s tiny Yardsail is a typical indoor/micro RC model that weighs less
than an ounce ready to fly with an RC system, motor, and battery.
The author’s Scratch-65: a 2.6-ounce design featured in a
construction article with plans in the February 2005 MA.
The new in-flight Li-Poly cell voltage-monitoring device called
the MM7 will soon be offered by SLK Electronics.
THIS IS THE 30th monthly column in which
I try to give you the best possible answers to
questions you have written or E-mailed to me.
Each new question is given a sequential
number for identification purposes.
Until now this column has appeared in the
pages of MA and additional questions and
answers have been posted on a special section
of the AMA Web site (www.modelair
craft.org). That Web page is now in the process
of being revised and, as such, there will be no
new postings in the foreseeable future.
What you read each month in print is
all you will see. I will advise you when we
are able to return to the original format.
The original “search process” by
categories will also be suspended until the
posting is back online.
In the meantime, I’m available to help
you locate specific subjects of interest. Just
drop me an E-mail. Also please keep
sending in your questions; that’s the only
way I can continue to provide this service
to readers.
09sig4.QXD 7/25/06 2:11 PM Page 101102 MODEL AVIATION
Hobby Lobby’s 3.5-ounce Graupner Mosquito is a typical micro indoor model sold as a kit.
It uses a Speed 250 motor and three 250 mAh Li Poly battery cells. It spans 22 inches.
If you have ever gotten to your flying field only to find your 12-volt field kit battery
dead, the VoltWatch monitoring device by Hobbico is for you.
Bob’s favorite hinge material is SR Batteries’ clear Gapless Hinge Tape. It is sold in
lengths that can be cut to suit the size of your particular models.
For those who use transmitter supporting
trays, 3D Hobby Shop’s “BigStik”
control-stick extensions provide a much
better “feel of flying.”
burp (turn on and off quickly), alerting you to
land as soon as possible.
By using this DPM, no cell in the pack
will ever go below the recommended
minimum voltage. This discharge technique,
along with balanced charging at
approximately a 1C current rate, will add
tremendously to the life of—and safe use
of—your Li-Poly battery packs.
While writing this answer I learned, to my
pleasant surprise, that Sid Kauffman—the
creator of the ElectriCalc motor-selection
program—has just developed his own
protection module, which he calls the MM7
In-Flight Cell Monitor.
This onboard device can handle packs
with two to seven Li-Poly cells. It weighs just
10 grams (0.35 ounce) and is expected to sell
for roughly $40 including shipping. The
MM7 is simple to hook up in your aircraft
and to set up. Best of all, it will plug into
most popular (individual cell wired) Li-Poly
Most modern ESCs, set up for use with
Li-Poly batteries, monitor the total pack
voltage down to something such as 3.0 volts
per cell. Therefore, a three-cell pack might be
cut off when the total of three-cell voltage
reaches 9.0. But as I just explained, it is
possible that one of the cells has gone
significantly lower than 3.0 volts while the
other two were actually higher than that.
If you were using a balancing charger,
such as the FMA Direct BalancePro HD or
Cellpro 4S, the cells would all be rebalanced
at the completion of the next charge.
However, if you are using an ordinary
charger that does not charge each cell
separately, you will have a battery pack that
is clearly out of balance and heading for rapid
deterioration.
The solution to this problem of
discharging Li-Poly batteries is to use a new
onboard monitoring device called a
Discharge Protection Module (DPM). FMA
Direct now sells DPMs for use with both of
their balancing systems (BalancePro HD and
Cellpro 4S).
Since FMA Direct’s special battery packs
are wired with access to the individual cell, it
is easy to monitor each cell in flight. When
the first cell hits 3.0 volts your motor will
09sig4.QXD 7/26/06 9:16 AM Page 102battery packs on the market, including
Thunder Power, Poly-Quest, Duralite, and
Hobby Lobby “Twenty.”
Standard mating connectors will be
available for five-pin (two to four cells) and
eight-pin (two to seven cells) battery packs.
The MM7 should be available by the time
you read this. Go to
www.slkelectronics.com for more
information.
Q246: “I consider myself an average RC
sport flier. I live in an area of our country
where winter weather makes it impossible
for me to fly. But I keep hearing all these
good things about flying indoors in gyms,
school auditoriums, and even inflatable
sports domes. How does one learn about
indoor RC flying?”
A246: I mentioned awhile ago that former
AMA Executive Director John Worth had
started his own webzine (Internet-oriented
magazine) called RC Micro World. This
“publication” is posted monthly to a secure
Web site you access by paying a
subscription fee.
To help John promote his specialized
publication, I recently prepared a guidetype
document I call the “Intro to
Indoor/Micro RC.” It was written with the
assumption that you already know
something about RC flying. But then it goes
on to cover all the details necessary to
build, assemble, and fly RC models at
indoor facilities.
This guide is available on a special free
portion of John’s Web page at www.cloud9
rc.com/indoorflying.asp. I urge you to look
at it because it will answer most of your
questions concerning getting started in
indoor RC flying.
Q247: “I’ve seen transmitter supporting
trays with a strap that goes around your
neck. Once supported, the need for
transmitter control-stick extensions
becomes obvious. Can you lead me to a
source of supply for extended-length
control sticks?”
A247: After a little searching I found 3D
Hobby Shop’s Web site at www.3dhobby
shop.com/detail.aspx?ID=993. It offers
modular aluminum transmitter-control-stick
extensions under the trade name “BigStix.”
One set is intended for JR and Spektrum
owners, and the other is for the Hitec or
Futaba transmitter owner. Each set sells for
$24.99. I found some other electric 3-D
accessory products on this Web page that
may interest many RC pilots.
Q248: “I’ve experienced a situation of
arriving at my flying field after a long drive
only to find out that my 12-volt field kit
battery is dead. Is there any kind of voltagemonitoring
device available?”
A248: Hobbico has a 12-volt batterymonitoring
device called the VoltWatch. It is
catalog item HCAP0331 and presently sells
for $9.99. You can find it at www.hobbico
.com/fieldequip/hcap0331.html.
This unit uses multicolored LEDs to let
you know the voltage range from 11.0 to
13.0 volts. It can be mounted to the outside
of your field kit box using double-stick tape.
Just make sure you press the “ON” test
button before taking off for your flying field.
Q249: “I had heard that a company is now
offering a radio-control skydiver which can
be dropped from an RC aircraft. I haven’t
seen it advertised as yet and was wondering
if you might direct me to the Web site.”
A249: I found a company that appears to
specialize in RC skydiving products. The
Web site is http://rcskydiving.com/
store/index.php?act=viewCat&catId=3. I
haven’t seen any of these products yet, but
the description on the Web page is thorough.
The site offers Micro Diver, which
consists of a 9-inch figure and a suitable
parachute; the total weight is 10 ounces. The
“diver” requires two microservos, a receiver,
and a four-cell battery pack.
The diver is carried aloft with an RC
model aircraft and then released at altitude.
A static line will open the chute on release.
Then a second pilot flies the diver down for a
landing.
This is only an announcement of the
product. I urge you to see the Web page for
more detailed information.
Q250: “I have noted in many of your
product reviews and construction articles
that you seem to favor the Gapless Hinge
Tape as sold by SR Batteries, Inc. What
made you so sold on this particular
product?”
A250: I was first introduced to this gapless
hinge material in 2002 when I was
reviewing the SR Batteries Bantam
monoplane and biplane park flyers. The
tape was supplied with both kits, which
were designed by SR Batteries owner
Larry Sribnick.
The tape was originally manufactured
by the 3M company. It is approximately 1
inch in width and is clear, with a sticky
cement applied to one side. SR Batteries
provides an excellent application sheet
along with the hinge material.
The installation technique is simple.
You line up the flying surface and control
surface (such as a stabilizer and elevator),
establishing a suitable spacing, and then
anchor the two surfaces with several pieces
of masking tape.
Peel off the protective backing on the
hinge tape, and apply it so that an equal
amount is on the flying surface and the
control surface. Press it down firmly to
make a solid contact, then remove the
masking tape. You will find the hinged
surface smooth and without gaps.
Because of the clear tape, you can
cover or paint your aircraft surfaces before
applying the tape. One thing you must be
aware of is that the cement used on this
tape is not fuelproof. Thus you can’t use
this material on a fuel-powered aircraft.
However, it is perfect for electric-powered
models and sailplanes.
I use the Gapless Hinge Tape on almost
all my aircraft. The only exception might
be a rudder that has a steerable tail wheel
at the lower extremity. That application
generally works better with a “Lite” hinge
or a molded-nylon hinge with a metal pin.
You can obtain the Gapless Hinge Tape
from SR Batteries Inc., Box 287, Bellport
NY 11713; Tel.: (631) 286-0079; Web
site: www.srbatteries.com.
That’s a wrap for this month! MA
Edition: Model Aviation - 2006/09
Page Numbers: 101,102,104
Q245: “I’ve read so much lately on the
subject of balancing the cells within a Li-Poly
battery pack. That the term ‘balancing’ refers
to the condition when all cells in the pack
have the same voltage.
“But I also hear that it is important to
monitor these same cells while they are being
discharged in flight. What’s the story on this
and what should I be doing to make this
happen?”
A245: You bring up an interesting point. Just
making sure the cells within your Li-Poly
battery are balanced (all have the same
voltage) takes into account only part of the
possible problem. Starting with all cells at the
same voltage doesn’t necessarily mean all
those cells will hit the same minimum cutoff
voltage at the end of a flight.
The capacity of each cell in a pack will
determine how fast it gets to some minimum
value, such as 3.0 volts. Depending on the
capacity, some cells will get to that level
before others.
FMA Direct offers an onboard monitoring device for Li-Poly batteries
September 2006 101
? Frequently Asked Questions Bob Aberle | [email protected]
Also included in this column:
• Intro to indoor/micro RC
• Transmitter-stick-length extenders
• Field kit battery voltage monitor
• RC Skydiving
• SR Batteries’ gapless hinge material
Scott Christensen’s tiny Yardsail is a typical indoor/micro RC model that weighs less
than an ounce ready to fly with an RC system, motor, and battery.
The author’s Scratch-65: a 2.6-ounce design featured in a
construction article with plans in the February 2005 MA.
The new in-flight Li-Poly cell voltage-monitoring device called
the MM7 will soon be offered by SLK Electronics.
THIS IS THE 30th monthly column in which
I try to give you the best possible answers to
questions you have written or E-mailed to me.
Each new question is given a sequential
number for identification purposes.
Until now this column has appeared in the
pages of MA and additional questions and
answers have been posted on a special section
of the AMA Web site (www.modelair
craft.org). That Web page is now in the process
of being revised and, as such, there will be no
new postings in the foreseeable future.
What you read each month in print is
all you will see. I will advise you when we
are able to return to the original format.
The original “search process” by
categories will also be suspended until the
posting is back online.
In the meantime, I’m available to help
you locate specific subjects of interest. Just
drop me an E-mail. Also please keep
sending in your questions; that’s the only
way I can continue to provide this service
to readers.
09sig4.QXD 7/25/06 2:11 PM Page 101102 MODEL AVIATION
Hobby Lobby’s 3.5-ounce Graupner Mosquito is a typical micro indoor model sold as a kit.
It uses a Speed 250 motor and three 250 mAh Li Poly battery cells. It spans 22 inches.
If you have ever gotten to your flying field only to find your 12-volt field kit battery
dead, the VoltWatch monitoring device by Hobbico is for you.
Bob’s favorite hinge material is SR Batteries’ clear Gapless Hinge Tape. It is sold in
lengths that can be cut to suit the size of your particular models.
For those who use transmitter supporting
trays, 3D Hobby Shop’s “BigStik”
control-stick extensions provide a much
better “feel of flying.”
burp (turn on and off quickly), alerting you to
land as soon as possible.
By using this DPM, no cell in the pack
will ever go below the recommended
minimum voltage. This discharge technique,
along with balanced charging at
approximately a 1C current rate, will add
tremendously to the life of—and safe use
of—your Li-Poly battery packs.
While writing this answer I learned, to my
pleasant surprise, that Sid Kauffman—the
creator of the ElectriCalc motor-selection
program—has just developed his own
protection module, which he calls the MM7
In-Flight Cell Monitor.
This onboard device can handle packs
with two to seven Li-Poly cells. It weighs just
10 grams (0.35 ounce) and is expected to sell
for roughly $40 including shipping. The
MM7 is simple to hook up in your aircraft
and to set up. Best of all, it will plug into
most popular (individual cell wired) Li-Poly
Most modern ESCs, set up for use with
Li-Poly batteries, monitor the total pack
voltage down to something such as 3.0 volts
per cell. Therefore, a three-cell pack might be
cut off when the total of three-cell voltage
reaches 9.0. But as I just explained, it is
possible that one of the cells has gone
significantly lower than 3.0 volts while the
other two were actually higher than that.
If you were using a balancing charger,
such as the FMA Direct BalancePro HD or
Cellpro 4S, the cells would all be rebalanced
at the completion of the next charge.
However, if you are using an ordinary
charger that does not charge each cell
separately, you will have a battery pack that
is clearly out of balance and heading for rapid
deterioration.
The solution to this problem of
discharging Li-Poly batteries is to use a new
onboard monitoring device called a
Discharge Protection Module (DPM). FMA
Direct now sells DPMs for use with both of
their balancing systems (BalancePro HD and
Cellpro 4S).
Since FMA Direct’s special battery packs
are wired with access to the individual cell, it
is easy to monitor each cell in flight. When
the first cell hits 3.0 volts your motor will
09sig4.QXD 7/26/06 9:16 AM Page 102battery packs on the market, including
Thunder Power, Poly-Quest, Duralite, and
Hobby Lobby “Twenty.”
Standard mating connectors will be
available for five-pin (two to four cells) and
eight-pin (two to seven cells) battery packs.
The MM7 should be available by the time
you read this. Go to
www.slkelectronics.com for more
information.
Q246: “I consider myself an average RC
sport flier. I live in an area of our country
where winter weather makes it impossible
for me to fly. But I keep hearing all these
good things about flying indoors in gyms,
school auditoriums, and even inflatable
sports domes. How does one learn about
indoor RC flying?”
A246: I mentioned awhile ago that former
AMA Executive Director John Worth had
started his own webzine (Internet-oriented
magazine) called RC Micro World. This
“publication” is posted monthly to a secure
Web site you access by paying a
subscription fee.
To help John promote his specialized
publication, I recently prepared a guidetype
document I call the “Intro to
Indoor/Micro RC.” It was written with the
assumption that you already know
something about RC flying. But then it goes
on to cover all the details necessary to
build, assemble, and fly RC models at
indoor facilities.
This guide is available on a special free
portion of John’s Web page at www.cloud9
rc.com/indoorflying.asp. I urge you to look
at it because it will answer most of your
questions concerning getting started in
indoor RC flying.
Q247: “I’ve seen transmitter supporting
trays with a strap that goes around your
neck. Once supported, the need for
transmitter control-stick extensions
becomes obvious. Can you lead me to a
source of supply for extended-length
control sticks?”
A247: After a little searching I found 3D
Hobby Shop’s Web site at www.3dhobby
shop.com/detail.aspx?ID=993. It offers
modular aluminum transmitter-control-stick
extensions under the trade name “BigStix.”
One set is intended for JR and Spektrum
owners, and the other is for the Hitec or
Futaba transmitter owner. Each set sells for
$24.99. I found some other electric 3-D
accessory products on this Web page that
may interest many RC pilots.
Q248: “I’ve experienced a situation of
arriving at my flying field after a long drive
only to find out that my 12-volt field kit
battery is dead. Is there any kind of voltagemonitoring
device available?”
A248: Hobbico has a 12-volt batterymonitoring
device called the VoltWatch. It is
catalog item HCAP0331 and presently sells
for $9.99. You can find it at www.hobbico
.com/fieldequip/hcap0331.html.
This unit uses multicolored LEDs to let
you know the voltage range from 11.0 to
13.0 volts. It can be mounted to the outside
of your field kit box using double-stick tape.
Just make sure you press the “ON” test
button before taking off for your flying field.
Q249: “I had heard that a company is now
offering a radio-control skydiver which can
be dropped from an RC aircraft. I haven’t
seen it advertised as yet and was wondering
if you might direct me to the Web site.”
A249: I found a company that appears to
specialize in RC skydiving products. The
Web site is http://rcskydiving.com/
store/index.php?act=viewCat&catId=3. I
haven’t seen any of these products yet, but
the description on the Web page is thorough.
The site offers Micro Diver, which
consists of a 9-inch figure and a suitable
parachute; the total weight is 10 ounces. The
“diver” requires two microservos, a receiver,
and a four-cell battery pack.
The diver is carried aloft with an RC
model aircraft and then released at altitude.
A static line will open the chute on release.
Then a second pilot flies the diver down for a
landing.
This is only an announcement of the
product. I urge you to see the Web page for
more detailed information.
Q250: “I have noted in many of your
product reviews and construction articles
that you seem to favor the Gapless Hinge
Tape as sold by SR Batteries, Inc. What
made you so sold on this particular
product?”
A250: I was first introduced to this gapless
hinge material in 2002 when I was
reviewing the SR Batteries Bantam
monoplane and biplane park flyers. The
tape was supplied with both kits, which
were designed by SR Batteries owner
Larry Sribnick.
The tape was originally manufactured
by the 3M company. It is approximately 1
inch in width and is clear, with a sticky
cement applied to one side. SR Batteries
provides an excellent application sheet
along with the hinge material.
The installation technique is simple.
You line up the flying surface and control
surface (such as a stabilizer and elevator),
establishing a suitable spacing, and then
anchor the two surfaces with several pieces
of masking tape.
Peel off the protective backing on the
hinge tape, and apply it so that an equal
amount is on the flying surface and the
control surface. Press it down firmly to
make a solid contact, then remove the
masking tape. You will find the hinged
surface smooth and without gaps.
Because of the clear tape, you can
cover or paint your aircraft surfaces before
applying the tape. One thing you must be
aware of is that the cement used on this
tape is not fuelproof. Thus you can’t use
this material on a fuel-powered aircraft.
However, it is perfect for electric-powered
models and sailplanes.
I use the Gapless Hinge Tape on almost
all my aircraft. The only exception might
be a rudder that has a steerable tail wheel
at the lower extremity. That application
generally works better with a “Lite” hinge
or a molded-nylon hinge with a metal pin.
You can obtain the Gapless Hinge Tape
from SR Batteries Inc., Box 287, Bellport
NY 11713; Tel.: (631) 286-0079; Web
site: www.srbatteries.com.
That’s a wrap for this month! MA