January 2009 155
Start thinking about the 2009 AMA Nationals
[[email protected]]
Control Line Navy Carrier Dick Perry
Also included in this column:
• 2008 Nats analysis
• Electric-powered Carrier
data
The Profile Carrier event at this year’s Nats featured a
variety of entries—and only two MO-1s!
Ted Kraver entered this Curtiss Helldiver SB2C-3 by Marvin
Martinez in Class II Nostalgia at the Nats. The engine is an O.S.
Gold Head .60.
Bill Calkins’ Skyray with a Scorpion HK3026 power plant shows
one of many mounting options for motors.
IT’S ALMOST TIME to plan vacation
time and make reservations for the 2009
Nats. Carrier will be flown Wednesday
through Friday, July 8-10.
Profile and Sportsman Profile will be
flown on Wednesday, July 8. Class I and
Class II will be contested on Thursday.
Unofficial events will be held Friday July 10
and will include Nostalgia Carrier, .15
Carrier, Skyray Carrier, and Electric Carrier
events. The Navy Carrier Society awards
banquet and annual meeting will take place
Thursday evening.
Nats Analysis: High speed and overall
placing were highly correlative this year for
complete flights in all CL Navy Carrier
events. The only situations in which low
speed had an influence on placing were in
cases of high speeds within 1 mph of each
other or slow speeds that were more than a
minute longer than that of the competitor
with the better high speed.
In Profile, the best high speed of 96.4
mph went to Pete Mazur. The dominant
engine in Profile was the Nelson (available
from Performance Specialties), with the top
five places and the top five high speeds
going to that brand of power plant.
The best low speed went to Pete Mazur at
356 seconds. Profile low speeds were more
closely correlated to overall placing than
high speeds, indicating that the better
performers were consistently superior in
both the high- and low-speed portions of the
event.
In Class I, Burt Brokaw had the best high
speed of 102.7 mph with a Nelson. In Class
II, the honors went to Pete Mazur at 99.9
01sig5.QXD 11/24/08 12:57 PM Page 155
mph with a Webra Speed .60. The large
engines were the fastest in Class II.
There were muffler-equipped engines in
Profile, Class I, and Class II this year,
allowing for head-to-head comparisons. In
each category, the muffler-equipped engines
were Nelsons. They were within 5 mph of the
open-exhaust engines in Profile and Class I,
finishing on top in Class I and being beaten
out in Profile. The Nelsons are designed for
10% fuel and mufflers, so their ability to
perform well is no surprise.
In all the events, both official and
unofficial, a great variety of equipment was
used. The obvious trends were MO-1 models
in Class I and Class II (no surprise there) and
Nelson engines in Profile. APC propellers
were used exclusively in this year’s official
events.
Electric Carrier Data: We are gaining a
little more experience with electric power,
but there has been limited data to allow any
particular brand or type of motor, power
supply, or controller to rise to the surface.
The only trend of note is the exclusive use of
brushless outrunner motors, Li-Poly batteries,
and Clancy Arnold’s U/Tronics control
systems that I’ve mentioned in prior columns.
The U/Tronics unit is normally employed
in conjunction with a standard three-line
control system (Brodak), with the throttle arm
connected to a rotary potentiometer. The
U/Tronics system needs a resistance range of
0 to 10,000 ohms. But most potentiometers
(pots) have a rotational range of
approximately 270°, so a 50,000-ohm pot is
used with a total throw of 50°-60°.
There are few differences in the
performance of various motor, ESC, and
battery brands, according to the specifications
that are available from the manufacturers and
distributors. With the wide variety of motor
designs, selecting power, voltage, and rpm
capability is largely a matter of deciding
approximately what rpm and power you want
and what size battery pack the model can
accommodate, and then searching the various
manufacturer and distributor Web sites to
identify a fit to a particular need.
What has been missing is specific data on
the power and current demands of electricpowered
Carrier (eCarrier) flying. To help in
selection, Pete Mazur has been collecting
data during his flights throughout 2008 using
the eLogger from Eagle Tree Systems, which
I discussed in the July Navy Carrier column.
He has consented to share the information he
collected.
Pete has been flying Skyray models
powered by an AXi 2826/08 outrunner motor
with a rating of 1130 Kv and a current
capacity of 55 amps for up to 60 seconds. The
motor is controlled by a Jeti Spin 66 ESC that
has a 70-amp rating. The motor turns an APC
10 x 8P propeller.
The batteries have varied slightly, being
adjusted to meet weight requirements for
competing in different events. For Skyray, the
battery is a Thunder Power 4S 3300 mAh
with a nominal voltage of 14.8 volts. Pete has
also used a Flight Power EVO 4S 3700 mAh
battery for a bit more endurance in lowspeed
flight.
Now for the good stuff. The current draw
for this configuration is approximately 95
amps until the motor reaches a static rpm, at
which point current drops to near 75 amps.
As the model accelerates and battery voltage
decreases, the current draw drops to less than
70 amps. The model is capable of 75-80 mph
high speed as measured in our event.
For the 23- to 24-second high speed, the
power consumed is approximately 540 mAh.
Achieving the 75-80 mph speeds with a 53-
ounce Skyray requires approximately 1,000
watts.
To fly a 60° hang for slow flight, the
motor is drawing 30-35 amps, or 450-500
watts. For a flight of approximately six
minutes total duration, the battery capacity
used is approximately 3000 mAh.
What does this mean? Power is primarily
what we’re interested in. Electric power is
the product of the current in amps and the
potential in volts. To increase speed to
approximately 95 mph requires an excess of
2,000 watts. The power required for low
speed will be approximately proportional to
the model’s weight.
A .15 eCarrier model (40 ounces
maximum) might need 400 watts for slow
speed. A Profile or Class I eCarrier model
(56 ounces maximum) might need roughly
500 watts, and a Class II eCarrier model
(approximately 64 ounces) might need
something on the order of 650-700 watts.
Practical limits of controllers and motors
on the market seem to indicate that there is
an availability, cost, cooling, and weight
limit of roughly 100 amps in high-speed
cruise power. That indicates that increased
high-speed performance would require an
increase in battery voltage as well as an
increase in motor current.
With a 75-80 mph high speed, the slowspeed
portion of the flight is more
demanding of total battery capacity than the
high-speed portion is. Since current goes up
for high speed, the battery’s ability to deliver
current can become a limiting factor. That,
too, is related to total battery capacity.
All this means that there should be a
variety of equipment and cost options for a
modeler who is starting out in eCarrier and
wants to be competitive. For Skyray and
.15 Carrier, with their speed limits, the
possible combinations should be virtually
endless.
I expect performance to evolve slowly
as optimum combinations are developed,
but there probably won’t be a revolutionary
discovery that outshines all previously used
equipment. I predict that eCarrier will not
be challenging glow-powered Carrier
performance in the near future.
Pete is switching to a speed controller
with a higher current capacity after having
premature shut-downs at Phoenix,
Arizona, a year ago. He believes that the
current draw was too near the controller’s
rated capacity under conditions of poor
cooling during slow flight and that the
controller was reaching its temperature
limit.
Pete highly recommends that you do
not skimp on current capacity for your
electronics and that you provide the speed
controller with as much cooling air as
possible. MA
Sources:
Performance Specialties
(775) 265-7523
www.pspec.com
Brodak
(724) 966-2726
www.brodak.com
Clancy Arnold, U/Tronics
(317) 387-1940
[email protected]
Eagle Tree Systems
(425) 614-0450
www.eagletreesystems.com
Edition: Model Aviation - 2009/01
Page Numbers: 155,156,157
Edition: Model Aviation - 2009/01
Page Numbers: 155,156,157
January 2009 155
Start thinking about the 2009 AMA Nationals
[[email protected]]
Control Line Navy Carrier Dick Perry
Also included in this column:
• 2008 Nats analysis
• Electric-powered Carrier
data
The Profile Carrier event at this year’s Nats featured a
variety of entries—and only two MO-1s!
Ted Kraver entered this Curtiss Helldiver SB2C-3 by Marvin
Martinez in Class II Nostalgia at the Nats. The engine is an O.S.
Gold Head .60.
Bill Calkins’ Skyray with a Scorpion HK3026 power plant shows
one of many mounting options for motors.
IT’S ALMOST TIME to plan vacation
time and make reservations for the 2009
Nats. Carrier will be flown Wednesday
through Friday, July 8-10.
Profile and Sportsman Profile will be
flown on Wednesday, July 8. Class I and
Class II will be contested on Thursday.
Unofficial events will be held Friday July 10
and will include Nostalgia Carrier, .15
Carrier, Skyray Carrier, and Electric Carrier
events. The Navy Carrier Society awards
banquet and annual meeting will take place
Thursday evening.
Nats Analysis: High speed and overall
placing were highly correlative this year for
complete flights in all CL Navy Carrier
events. The only situations in which low
speed had an influence on placing were in
cases of high speeds within 1 mph of each
other or slow speeds that were more than a
minute longer than that of the competitor
with the better high speed.
In Profile, the best high speed of 96.4
mph went to Pete Mazur. The dominant
engine in Profile was the Nelson (available
from Performance Specialties), with the top
five places and the top five high speeds
going to that brand of power plant.
The best low speed went to Pete Mazur at
356 seconds. Profile low speeds were more
closely correlated to overall placing than
high speeds, indicating that the better
performers were consistently superior in
both the high- and low-speed portions of the
event.
In Class I, Burt Brokaw had the best high
speed of 102.7 mph with a Nelson. In Class
II, the honors went to Pete Mazur at 99.9
01sig5.QXD 11/24/08 12:57 PM Page 155
mph with a Webra Speed .60. The large
engines were the fastest in Class II.
There were muffler-equipped engines in
Profile, Class I, and Class II this year,
allowing for head-to-head comparisons. In
each category, the muffler-equipped engines
were Nelsons. They were within 5 mph of the
open-exhaust engines in Profile and Class I,
finishing on top in Class I and being beaten
out in Profile. The Nelsons are designed for
10% fuel and mufflers, so their ability to
perform well is no surprise.
In all the events, both official and
unofficial, a great variety of equipment was
used. The obvious trends were MO-1 models
in Class I and Class II (no surprise there) and
Nelson engines in Profile. APC propellers
were used exclusively in this year’s official
events.
Electric Carrier Data: We are gaining a
little more experience with electric power,
but there has been limited data to allow any
particular brand or type of motor, power
supply, or controller to rise to the surface.
The only trend of note is the exclusive use of
brushless outrunner motors, Li-Poly batteries,
and Clancy Arnold’s U/Tronics control
systems that I’ve mentioned in prior columns.
The U/Tronics unit is normally employed
in conjunction with a standard three-line
control system (Brodak), with the throttle arm
connected to a rotary potentiometer. The
U/Tronics system needs a resistance range of
0 to 10,000 ohms. But most potentiometers
(pots) have a rotational range of
approximately 270°, so a 50,000-ohm pot is
used with a total throw of 50°-60°.
There are few differences in the
performance of various motor, ESC, and
battery brands, according to the specifications
that are available from the manufacturers and
distributors. With the wide variety of motor
designs, selecting power, voltage, and rpm
capability is largely a matter of deciding
approximately what rpm and power you want
and what size battery pack the model can
accommodate, and then searching the various
manufacturer and distributor Web sites to
identify a fit to a particular need.
What has been missing is specific data on
the power and current demands of electricpowered
Carrier (eCarrier) flying. To help in
selection, Pete Mazur has been collecting
data during his flights throughout 2008 using
the eLogger from Eagle Tree Systems, which
I discussed in the July Navy Carrier column.
He has consented to share the information he
collected.
Pete has been flying Skyray models
powered by an AXi 2826/08 outrunner motor
with a rating of 1130 Kv and a current
capacity of 55 amps for up to 60 seconds. The
motor is controlled by a Jeti Spin 66 ESC that
has a 70-amp rating. The motor turns an APC
10 x 8P propeller.
The batteries have varied slightly, being
adjusted to meet weight requirements for
competing in different events. For Skyray, the
battery is a Thunder Power 4S 3300 mAh
with a nominal voltage of 14.8 volts. Pete has
also used a Flight Power EVO 4S 3700 mAh
battery for a bit more endurance in lowspeed
flight.
Now for the good stuff. The current draw
for this configuration is approximately 95
amps until the motor reaches a static rpm, at
which point current drops to near 75 amps.
As the model accelerates and battery voltage
decreases, the current draw drops to less than
70 amps. The model is capable of 75-80 mph
high speed as measured in our event.
For the 23- to 24-second high speed, the
power consumed is approximately 540 mAh.
Achieving the 75-80 mph speeds with a 53-
ounce Skyray requires approximately 1,000
watts.
To fly a 60° hang for slow flight, the
motor is drawing 30-35 amps, or 450-500
watts. For a flight of approximately six
minutes total duration, the battery capacity
used is approximately 3000 mAh.
What does this mean? Power is primarily
what we’re interested in. Electric power is
the product of the current in amps and the
potential in volts. To increase speed to
approximately 95 mph requires an excess of
2,000 watts. The power required for low
speed will be approximately proportional to
the model’s weight.
A .15 eCarrier model (40 ounces
maximum) might need 400 watts for slow
speed. A Profile or Class I eCarrier model
(56 ounces maximum) might need roughly
500 watts, and a Class II eCarrier model
(approximately 64 ounces) might need
something on the order of 650-700 watts.
Practical limits of controllers and motors
on the market seem to indicate that there is
an availability, cost, cooling, and weight
limit of roughly 100 amps in high-speed
cruise power. That indicates that increased
high-speed performance would require an
increase in battery voltage as well as an
increase in motor current.
With a 75-80 mph high speed, the slowspeed
portion of the flight is more
demanding of total battery capacity than the
high-speed portion is. Since current goes up
for high speed, the battery’s ability to deliver
current can become a limiting factor. That,
too, is related to total battery capacity.
All this means that there should be a
variety of equipment and cost options for a
modeler who is starting out in eCarrier and
wants to be competitive. For Skyray and
.15 Carrier, with their speed limits, the
possible combinations should be virtually
endless.
I expect performance to evolve slowly
as optimum combinations are developed,
but there probably won’t be a revolutionary
discovery that outshines all previously used
equipment. I predict that eCarrier will not
be challenging glow-powered Carrier
performance in the near future.
Pete is switching to a speed controller
with a higher current capacity after having
premature shut-downs at Phoenix,
Arizona, a year ago. He believes that the
current draw was too near the controller’s
rated capacity under conditions of poor
cooling during slow flight and that the
controller was reaching its temperature
limit.
Pete highly recommends that you do
not skimp on current capacity for your
electronics and that you provide the speed
controller with as much cooling air as
possible. MA
Sources:
Performance Specialties
(775) 265-7523
www.pspec.com
Brodak
(724) 966-2726
www.brodak.com
Clancy Arnold, U/Tronics
(317) 387-1940
[email protected]
Eagle Tree Systems
(425) 614-0450
www.eagletreesystems.com
Edition: Model Aviation - 2009/01
Page Numbers: 155,156,157
January 2009 155
Start thinking about the 2009 AMA Nationals
[[email protected]]
Control Line Navy Carrier Dick Perry
Also included in this column:
• 2008 Nats analysis
• Electric-powered Carrier
data
The Profile Carrier event at this year’s Nats featured a
variety of entries—and only two MO-1s!
Ted Kraver entered this Curtiss Helldiver SB2C-3 by Marvin
Martinez in Class II Nostalgia at the Nats. The engine is an O.S.
Gold Head .60.
Bill Calkins’ Skyray with a Scorpion HK3026 power plant shows
one of many mounting options for motors.
IT’S ALMOST TIME to plan vacation
time and make reservations for the 2009
Nats. Carrier will be flown Wednesday
through Friday, July 8-10.
Profile and Sportsman Profile will be
flown on Wednesday, July 8. Class I and
Class II will be contested on Thursday.
Unofficial events will be held Friday July 10
and will include Nostalgia Carrier, .15
Carrier, Skyray Carrier, and Electric Carrier
events. The Navy Carrier Society awards
banquet and annual meeting will take place
Thursday evening.
Nats Analysis: High speed and overall
placing were highly correlative this year for
complete flights in all CL Navy Carrier
events. The only situations in which low
speed had an influence on placing were in
cases of high speeds within 1 mph of each
other or slow speeds that were more than a
minute longer than that of the competitor
with the better high speed.
In Profile, the best high speed of 96.4
mph went to Pete Mazur. The dominant
engine in Profile was the Nelson (available
from Performance Specialties), with the top
five places and the top five high speeds
going to that brand of power plant.
The best low speed went to Pete Mazur at
356 seconds. Profile low speeds were more
closely correlated to overall placing than
high speeds, indicating that the better
performers were consistently superior in
both the high- and low-speed portions of the
event.
In Class I, Burt Brokaw had the best high
speed of 102.7 mph with a Nelson. In Class
II, the honors went to Pete Mazur at 99.9
01sig5.QXD 11/24/08 12:57 PM Page 155
mph with a Webra Speed .60. The large
engines were the fastest in Class II.
There were muffler-equipped engines in
Profile, Class I, and Class II this year,
allowing for head-to-head comparisons. In
each category, the muffler-equipped engines
were Nelsons. They were within 5 mph of the
open-exhaust engines in Profile and Class I,
finishing on top in Class I and being beaten
out in Profile. The Nelsons are designed for
10% fuel and mufflers, so their ability to
perform well is no surprise.
In all the events, both official and
unofficial, a great variety of equipment was
used. The obvious trends were MO-1 models
in Class I and Class II (no surprise there) and
Nelson engines in Profile. APC propellers
were used exclusively in this year’s official
events.
Electric Carrier Data: We are gaining a
little more experience with electric power,
but there has been limited data to allow any
particular brand or type of motor, power
supply, or controller to rise to the surface.
The only trend of note is the exclusive use of
brushless outrunner motors, Li-Poly batteries,
and Clancy Arnold’s U/Tronics control
systems that I’ve mentioned in prior columns.
The U/Tronics unit is normally employed
in conjunction with a standard three-line
control system (Brodak), with the throttle arm
connected to a rotary potentiometer. The
U/Tronics system needs a resistance range of
0 to 10,000 ohms. But most potentiometers
(pots) have a rotational range of
approximately 270°, so a 50,000-ohm pot is
used with a total throw of 50°-60°.
There are few differences in the
performance of various motor, ESC, and
battery brands, according to the specifications
that are available from the manufacturers and
distributors. With the wide variety of motor
designs, selecting power, voltage, and rpm
capability is largely a matter of deciding
approximately what rpm and power you want
and what size battery pack the model can
accommodate, and then searching the various
manufacturer and distributor Web sites to
identify a fit to a particular need.
What has been missing is specific data on
the power and current demands of electricpowered
Carrier (eCarrier) flying. To help in
selection, Pete Mazur has been collecting
data during his flights throughout 2008 using
the eLogger from Eagle Tree Systems, which
I discussed in the July Navy Carrier column.
He has consented to share the information he
collected.
Pete has been flying Skyray models
powered by an AXi 2826/08 outrunner motor
with a rating of 1130 Kv and a current
capacity of 55 amps for up to 60 seconds. The
motor is controlled by a Jeti Spin 66 ESC that
has a 70-amp rating. The motor turns an APC
10 x 8P propeller.
The batteries have varied slightly, being
adjusted to meet weight requirements for
competing in different events. For Skyray, the
battery is a Thunder Power 4S 3300 mAh
with a nominal voltage of 14.8 volts. Pete has
also used a Flight Power EVO 4S 3700 mAh
battery for a bit more endurance in lowspeed
flight.
Now for the good stuff. The current draw
for this configuration is approximately 95
amps until the motor reaches a static rpm, at
which point current drops to near 75 amps.
As the model accelerates and battery voltage
decreases, the current draw drops to less than
70 amps. The model is capable of 75-80 mph
high speed as measured in our event.
For the 23- to 24-second high speed, the
power consumed is approximately 540 mAh.
Achieving the 75-80 mph speeds with a 53-
ounce Skyray requires approximately 1,000
watts.
To fly a 60° hang for slow flight, the
motor is drawing 30-35 amps, or 450-500
watts. For a flight of approximately six
minutes total duration, the battery capacity
used is approximately 3000 mAh.
What does this mean? Power is primarily
what we’re interested in. Electric power is
the product of the current in amps and the
potential in volts. To increase speed to
approximately 95 mph requires an excess of
2,000 watts. The power required for low
speed will be approximately proportional to
the model’s weight.
A .15 eCarrier model (40 ounces
maximum) might need 400 watts for slow
speed. A Profile or Class I eCarrier model
(56 ounces maximum) might need roughly
500 watts, and a Class II eCarrier model
(approximately 64 ounces) might need
something on the order of 650-700 watts.
Practical limits of controllers and motors
on the market seem to indicate that there is
an availability, cost, cooling, and weight
limit of roughly 100 amps in high-speed
cruise power. That indicates that increased
high-speed performance would require an
increase in battery voltage as well as an
increase in motor current.
With a 75-80 mph high speed, the slowspeed
portion of the flight is more
demanding of total battery capacity than the
high-speed portion is. Since current goes up
for high speed, the battery’s ability to deliver
current can become a limiting factor. That,
too, is related to total battery capacity.
All this means that there should be a
variety of equipment and cost options for a
modeler who is starting out in eCarrier and
wants to be competitive. For Skyray and
.15 Carrier, with their speed limits, the
possible combinations should be virtually
endless.
I expect performance to evolve slowly
as optimum combinations are developed,
but there probably won’t be a revolutionary
discovery that outshines all previously used
equipment. I predict that eCarrier will not
be challenging glow-powered Carrier
performance in the near future.
Pete is switching to a speed controller
with a higher current capacity after having
premature shut-downs at Phoenix,
Arizona, a year ago. He believes that the
current draw was too near the controller’s
rated capacity under conditions of poor
cooling during slow flight and that the
controller was reaching its temperature
limit.
Pete highly recommends that you do
not skimp on current capacity for your
electronics and that you provide the speed
controller with as much cooling air as
possible. MA
Sources:
Performance Specialties
(775) 265-7523
www.pspec.com
Brodak
(724) 966-2726
www.brodak.com
Clancy Arnold, U/Tronics
(317) 387-1940
[email protected]
Eagle Tree Systems
(425) 614-0450
www.eagletreesystems.com