Swashplate: Compass Model Atom 500E/CF ARF - 2009/12

42 MODEL AVIATION
MICHAEL RAMSEY
Swashplate: Compass Model Atom 500E/CF ARF
The el e ct ric- p ow e r
a d v anta ge is
ob v i ou s in this
com pa c t m achi ne
A versatile machine, the Compass Model Atom 500 is good for simply hovering
around but excels in 3-D. It’s a tight machine!
The builder had wired the included ESC, with plugs for battery and motor. The 500 is
available with either carbon fiber (shown) or G10 parts.
The electric-power
advantage is
obvious in this
compact machine
THE NUMBER IN the helicopter’s name
threw me at first. After several learning and
fun seasons with 450-class machines, the
Atom 500 came along. My expectation
regarding the size difference was that the
increase would be minor; helicopters are
named based on either the motor or the
blade size it uses.
Happy me, with lots of 450-classhelicopter
experience (models named for
the motor class), my eyes nearly popped out
when the Atom 500 arrived (named for the
blade size). Just 50 little number values
different, this aircraft is almost twice the
size of the other. A positive surprise,
however, the consideration meant looking at
accessorizing to suit the larger set of values.
KBDD was the distributor at the time the
Atom 500 project started. The importation
process was beginning, and all that was
available under the Atom name was the
carbon-fiber-frame version.
Two Atom models are offered; the other
has frames and flat milled parts made from
G10 material, and both are ARFs. The cost
difference is roughly $50. The carbon-fiber
frame is stiffer and a smaller advantage in
weight compared with the electronically
passive circuit board-like material.
Better than an ARF, the Atom 500 came
with the motor and ESC, both of which were
healthy. Many say that the included 500 BL
HT motor is oversized, but since when has
that been a bad thing for anything offered as
a 3-D helicopter pilot’s ultimate dream?
The 60-amp ESC is prepared, minus the
battery and motor connectors. Its BEC can
handle 3 amps of load from the servos and
accessories. Planning on flying
conservatively at first, I predicted that a
separate BEC might be needed later.
Sport fliers will consider the nice
offering from mini digital and nondigital
servos from Hitec. Nondigitals would fit
well into the smartly shaped and smartly
located servo openings.
The 3-D and precision pilots will
demand performance that only digital servos
can offer. After all, with three directly
linked servos managing the CCPM cyclic
controls, “overpowered” isn’t all that bad of
an idea, as I mentioned.
The JR DS3517 servos used for the
cyclic have metal gears for durability,
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:44 AM Page 42
December 2009 43
Static photos by William Ramsey Flight photos by Jay Smith
Today’s 35C batteries are an electric
helicopter’s best friend. Common Sense
RC’s 2600 mAh 6S pack provides excellent
power and, so far, long life.
The all-metal head has robust features
including an 8mm hardened mast and large
blade grips with thrust bearings, all factory
assembled.
The ESC provides enough power to the
digital servos and tail-stabilization system.
Serious 3-D pilots should consider adding a
separate BEC.
The JR gyro is easy to set up, solid, and quick
to respond when asked. It’s finitely adjusted
through the transmitter programming.
The included motor is oversized with a
relatively high Kv rating, so it has a lot of
torque and provides high speed.
The Spektrum AR6200’s antenna receiver clears the model’s carbon-fiber side frames.
Grommets were added to prevent wire chafing.
JR DS3517 servos provide plenty of pop to
the CCPM cyclic-control mechanics.
Compass provides custom servo arms for JR
and Futaba brands.
The short tail box is machined from one
piece of aluminum. The twin-point control
lever on the tail-pitch yoke is precise.
The oversized tailboom locks into
the mounting box. Heat-shrink
tubing around the receiver antenna
helps maintain correct orientation.
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:45 AM Page 43
44 MODEL AVIATION
The Atom 500 doesn’t mind the wind much at all. Its low profile and low
CG help the model roll cleanly. The author used MAH 420mm blades
from MRC for testing.
Size every link and lubricate all pivot points. This is
an extraordinarily tight machine out of the box,
and it stays that way; it’s shown going on 55 flights.
excellent centering, and strong power. They
fit into the frame with room to spare, which
meant that the grommets needed to be offset
a bit, to fully secure the case. Servos that
wobble in their mounts can cause trimming
issues, so choose a mini-sized servo with
four lug points.
On the tail, the JR G7703D found a home
on the aft-located gyro plate, straight above
the frame-located tail-rotor servo. That spot
was filled with the smallest tail-rotor servo
JR offered: the S3500G. (The new JR
G3703D gyro system would also do the job
nicely.)
I like boom-mounted tail-rotor servos on
electric-powered helicopters for their ease of
adjustability, but the Atom’s tail-rotorcontrol
servo location makes sense for lateral
and vertical balance. The nice thing about
boom-mounted servos is that they move with
the boom in case drive-belt tension requires
adjustment.
A good thing about the Atom is that the
belt is dimensionally superior to that used on
a pro-type 50-class glow helicopter. A strong
belt won’t need adjustment, so here I am
again, okay with the tail-rotor-servo location.
Test-Model Details
Motor used: Compass 500 BL HT,
1080 Kv (included)
Battery: 22.2-volt, 2600 mAh 35C
Common Sense Li-Poly
Radio system: Spektrum DX6i
transmitter, Spektrum AR6200
receiver, three JR DS3517 cyclic
servos, JR S3500G tail servo, JR
G7703D gyro, Compass Premium-60
ESC (with 3-amp BEC)
Main blades: 420mm MAH carbon
fiber
Tail blades: KBDD 70mm (4mm
hub)
Paddles: KBDD 500 class
Ready-to-fly weight: 64.8 ounces
Flight duration: Four to seven
minutes
Pluses and Minuses
+•
Precision ECCPM 120° metal
swashplate.
• Aluminum rotor head and tail-rotor
gearbox.
• Strong G10 or carbon-fiber frame
design.
• Low parts count.
• 80% preassembled.
• Extra-large boom avoids static
discharge.
• Oversized power system meets low
demand. -•
Exceedingly tight ball links (better
than too loose).
• Limited battery capacity.
• Oversized servo openings.
Specifications
Rotor diameter: 962mm
Weight: 1.75 kilograms
Length: 835mm
Height: 270mm
Motor: 500 watts
Gear ratio: 8T, 9.75:1:4.286; 9T,
8.67:1:4.286
Construction: Carbon fiber (optional
G10 frame)
Control system: CCPM 120° swashplate
Drive system: Belt-driven tail rotor
Main rotor blades: 420mm main,
70mm tail
Tailboom: Oversized, aluminum
Canopy: Factory-painted fiberglass
Landing gear: Multipart plastic-andaluminum
assembly
Battery: 14.4- to 22.2-volt Li-Poly (6S
recommended)
Requires: Six-channel helicopter radio
system, gyro, digital miniservos
Price: $499.95 ($459.95 for the G-10
version)
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:45 AM Page 44
The Atom is sleek and low-profile. Part of
that look comes from the absence of tailboom
supports. That echoes one of Compass
Model’s major goals: to offer performance
helicopters with low parts counts.
Because the powder-coated aluminum
tailboom is large in diameter, it’s good at
withstanding loads without the support of
additional bracing. To keep the boom itself
from twisting, it’s keyed into the frame and
tail cases. Once snugged into position, it
doesn’t so much as shimmy.
Play (in the fit of parts) is expected with
a helicopter; however, after a season of
flying my Atom 500, it doesn’t have one bit
of slop, or play, in the parts. That includes
the programmable head.
When assembling the machine, I had to
remove the prefitted linkages and size them
because they were so tight. They’re still
slightly on the snug side. Electric helicopters
don’t get lubricated as glow-powered
helicopters do, so from time to time the
Atom’s swashplate, sliders, and links get a
touch of lubricant.
As mentioned, the model came
assembled with even the motor installed,
with the stock nine-tooth pinion. The
disappointing part about the Atom’s being
an ARF is that enjoying the engineering
majesty is left for later, when maintenance
or repair is needed.
The main shaft is stout, 8mm thick, and
fairly short. The stepped drive gear has
heavy teeth that withstand torque from the
high-output motor and jumpy throttle
changes I have asked of it.
Still, its inner supportive webbing is
light, which is good for when the ground
impacts it improperly. That part will gladly
sacrifice itself, to save more valuable (and
expensive) parts of the drive system.
I downloaded the instruction manual and
highly recommend spending the ink if you
have a color printer. I found no
complications with the manual other than
the occasional hardware-dimension
variation. The good thing is that long bolts
can easily be shortened.
It was considerate that Compass thought,
as I have, that installing the servos before
everything else on the frame makes that part
of the job easier. It’s less awkward.
To prevent the belt from slipping, keep
play in its tension to a bare minimum. I can
barely flex mine between the main gear and
the pulley tensioners. Condition the belt
with WD-40 on a regular basis.
Without boom supports, there’s no place
to mount a horizontal stabilizer. So Compass
left that part off. Most 3-D pilots remove the
stabilizer anyway, because it creates
unwanted drag in flips.
As are the frame sides, the vertical fin is
robust. I have yet to see it shake even a little.
The fin is a bit short, though.
If you’re careless, a tilt on the ground
can quickly modify the stock plastic tail
blades so that they’ll fit on a 450-class
machine. I thought the stock blades were too
flexible anyway. The KBDD blades on there
now work great.
The sleek fiberglass canopy is just large
enough to cover the recommended 6S 2600
mAh Li-Poly battery. I found batteries that
were a really tight fit, but the Common Sense
2600 35C that came out recently is a homerun
match for this machine.
Regardless, 25C batteries are the lowestrated
packs to run in this machine. It demands
low-resistance power, and, as the pilot, you’ll
want that power available.
My prepainted canopy has the old color
scheme. As it would arrive today from
Common Sense RC, the redesigned canopy
has more yellow than white. Both are
attractive. The molded-in grommet and
Delron lower bracket mount locations were
spot-on.
A long-range radio system is required for
this class of machine. I like the Spektrum
DX6i transmitter’s simplicity, and the smooth
throttle and switch locations suit my tastes.
The Atom includes servo arms that are
sized appropriately to achieve the correct
geometry with the swashplate. Two sets are
provided; one for JR and one for Futaba servo
users.
Something I would like to see revised on
future Atom 500 kits is the flybar. The
independent flybar stabilizer arms lock on
with a grub screw. A precision-machined flat
at the arm location on the flybar would not
only aid in alignment, but would also ensure
the accurate orientation of the arms.
I know I claimed that the Atom 500 was
named for the size of blades it uses, but the
recommended size is 420mm-430mm—not
500. That’s silly, huh? I don’t make the rules;
I merely report them.
Available from Model Rectifier
Corporation, MAH makes some of the finest
carbon-fiber helicopter blades on the market.
Visit a dealer to get yours.
The 420mm MAH set on my machine is
balanced and beautifully finished. I haven’t
had the need to test a set of 430mm blades,
but I suspect they’ll add to the stability of an
already well-balanced machine.
As for experimenting, I played with
batteries, tail blades (had to), and paddles.
KongPower has a very light 25C 2600 mAh
6S pack that’s great for sport-flying. It got
hotter than the rest when I pushed it.
The heartiest battery I tested was the RFI
3200 mAh 6S, which also has a 25C rating.
Available from Model Rectifier Corporation,
this pack tipped the helicopter off of its CG
fun spot but couldn’t get hurt, no matter how
hard I flew.
So far, I’m happiest flying the Atom with
a 2600 mAh 35C 6S pack from Common
Sense. I don’t know if it’s custom-made for
this machine, but it ought to be. Expect flights
to last four minutes if you’re a mean 3-D
pilot; five minutes if you’re learning 3-D; six
minutes if you can fly, loop, and stuff; or
eight minutes if all you’re up to doing is
hovering around.
Flying the Atom for the first time gave me
that “OMG!” feeling. As I mentioned, my
practice with electrics came from 450-class
machines.
The Atom 500 is a Cadillac by
comparison, but with Corvette
performance. The head speed and power
was scary at first, but that’s the way these
machines are and I quickly got used to it—
also known as “spoiled.”
Forward flight requires a touch of
forward trim, but that’s because it’s
missing a huge stabilizer, as is seen on
F3C helicopters. The Atom is rock solid in
a hover, as if I’m flying a 30-class glowpowered
helicopter. When gusty
conditions spin up, I never hesitate to fly
the Atom; it hardly notices the wind.
I have approximately 12° of pitch in
both positive and negative curves. I can
feel the bite the power of the machine has,
and full collective is unnecessary to
appreciate that point.
Tick-ticks are my new showstopping
routine, because the Atom has the “pop” to
arrest any approach angle. I get more
aggressive with the model every time I fly it.
Back to the experiment thought, my
latest “like” is the new paddles from
KBDD (Compass helicopters’ previous
distributor). That company makes the only
replacement upgrade paddles, since the
2.5mm flybar is unique. The paddles
smoothed out the Atom but took away
none of its authority. And their bright
color makes the machine a little easier to
see.
When you’re learning, or even if you’re
great at flying helicopters, service and parts
availability is paramount. Don’t panic
because Compass Model has been passed
around to different US distributors;
probably at least 100 dealers here carry
parts for this line. I don’t think anyone will
be disappointed with the Atom 500. MA
Michael Ramsey
[email protected]
Manufacturer/Distributor:
Compass Model/Common Sense RC
9725 Owensmouth Ave.
Chatsworth CA 91311
(866) 405-8811
www.commonsenserc.com
Sources:
KBDD LLC
(614) 863-1111
www.kbddintl.com
JR
(800) 338-4639
www.jrradios.com
Spektrum RC
(800) 338-4639
www.spektrumrc.com
Model Rectifier Corporation
(732) 225-2100
www.modelrec.com
Other Published Reviews:
None known at time of publication

42 MODEL AVIATION
MICHAEL RAMSEY
Swashplate: Compass Model Atom 500E/CF ARF
The el e ct ric- p ow e r
a d v anta ge is
ob v i ou s in this
com pa c t m achi ne
A versatile machine, the Compass Model Atom 500 is good for simply hovering
around but excels in 3-D. It’s a tight machine!
The builder had wired the included ESC, with plugs for battery and motor. The 500 is
available with either carbon fiber (shown) or G10 parts.
The electric-power
advantage is
obvious in this
compact machine
THE NUMBER IN the helicopter’s name
threw me at first. After several learning and
fun seasons with 450-class machines, the
Atom 500 came along. My expectation
regarding the size difference was that the
increase would be minor; helicopters are
named based on either the motor or the
blade size it uses.
Happy me, with lots of 450-classhelicopter
experience (models named for
the motor class), my eyes nearly popped out
when the Atom 500 arrived (named for the
blade size). Just 50 little number values
different, this aircraft is almost twice the
size of the other. A positive surprise,
however, the consideration meant looking at
accessorizing to suit the larger set of values.
KBDD was the distributor at the time the
Atom 500 project started. The importation
process was beginning, and all that was
available under the Atom name was the
carbon-fiber-frame version.
Two Atom models are offered; the other
has frames and flat milled parts made from
G10 material, and both are ARFs. The cost
difference is roughly $50. The carbon-fiber
frame is stiffer and a smaller advantage in
weight compared with the electronically
passive circuit board-like material.
Better than an ARF, the Atom 500 came
with the motor and ESC, both of which were
healthy. Many say that the included 500 BL
HT motor is oversized, but since when has
that been a bad thing for anything offered as
a 3-D helicopter pilot’s ultimate dream?
The 60-amp ESC is prepared, minus the
battery and motor connectors. Its BEC can
handle 3 amps of load from the servos and
accessories. Planning on flying
conservatively at first, I predicted that a
separate BEC might be needed later.
Sport fliers will consider the nice
offering from mini digital and nondigital
servos from Hitec. Nondigitals would fit
well into the smartly shaped and smartly
located servo openings.
The 3-D and precision pilots will
demand performance that only digital servos
can offer. After all, with three directly
linked servos managing the CCPM cyclic
controls, “overpowered” isn’t all that bad of
an idea, as I mentioned.
The JR DS3517 servos used for the
cyclic have metal gears for durability,
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:44 AM Page 42
December 2009 43
Static photos by William Ramsey Flight photos by Jay Smith
Today’s 35C batteries are an electric
helicopter’s best friend. Common Sense
RC’s 2600 mAh 6S pack provides excellent
power and, so far, long life.
The all-metal head has robust features
including an 8mm hardened mast and large
blade grips with thrust bearings, all factory
assembled.
The ESC provides enough power to the
digital servos and tail-stabilization system.
Serious 3-D pilots should consider adding a
separate BEC.
The JR gyro is easy to set up, solid, and quick
to respond when asked. It’s finitely adjusted
through the transmitter programming.
The included motor is oversized with a
relatively high Kv rating, so it has a lot of
torque and provides high speed.
The Spektrum AR6200’s antenna receiver clears the model’s carbon-fiber side frames.
Grommets were added to prevent wire chafing.
JR DS3517 servos provide plenty of pop to
the CCPM cyclic-control mechanics.
Compass provides custom servo arms for JR
and Futaba brands.
The short tail box is machined from one
piece of aluminum. The twin-point control
lever on the tail-pitch yoke is precise.
The oversized tailboom locks into
the mounting box. Heat-shrink
tubing around the receiver antenna
helps maintain correct orientation.
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:45 AM Page 43
44 MODEL AVIATION
The Atom 500 doesn’t mind the wind much at all. Its low profile and low
CG help the model roll cleanly. The author used MAH 420mm blades
from MRC for testing.
Size every link and lubricate all pivot points. This is
an extraordinarily tight machine out of the box,
and it stays that way; it’s shown going on 55 flights.
excellent centering, and strong power. They
fit into the frame with room to spare, which
meant that the grommets needed to be offset
a bit, to fully secure the case. Servos that
wobble in their mounts can cause trimming
issues, so choose a mini-sized servo with
four lug points.
On the tail, the JR G7703D found a home
on the aft-located gyro plate, straight above
the frame-located tail-rotor servo. That spot
was filled with the smallest tail-rotor servo
JR offered: the S3500G. (The new JR
G3703D gyro system would also do the job
nicely.)
I like boom-mounted tail-rotor servos on
electric-powered helicopters for their ease of
adjustability, but the Atom’s tail-rotorcontrol
servo location makes sense for lateral
and vertical balance. The nice thing about
boom-mounted servos is that they move with
the boom in case drive-belt tension requires
adjustment.
A good thing about the Atom is that the
belt is dimensionally superior to that used on
a pro-type 50-class glow helicopter. A strong
belt won’t need adjustment, so here I am
again, okay with the tail-rotor-servo location.
Test-Model Details
Motor used: Compass 500 BL HT,
1080 Kv (included)
Battery: 22.2-volt, 2600 mAh 35C
Common Sense Li-Poly
Radio system: Spektrum DX6i
transmitter, Spektrum AR6200
receiver, three JR DS3517 cyclic
servos, JR S3500G tail servo, JR
G7703D gyro, Compass Premium-60
ESC (with 3-amp BEC)
Main blades: 420mm MAH carbon
fiber
Tail blades: KBDD 70mm (4mm
hub)
Paddles: KBDD 500 class
Ready-to-fly weight: 64.8 ounces
Flight duration: Four to seven
minutes
Pluses and Minuses
+•
Precision ECCPM 120° metal
swashplate.
• Aluminum rotor head and tail-rotor
gearbox.
• Strong G10 or carbon-fiber frame
design.
• Low parts count.
• 80% preassembled.
• Extra-large boom avoids static
discharge.
• Oversized power system meets low
demand. -•
Exceedingly tight ball links (better
than too loose).
• Limited battery capacity.
• Oversized servo openings.
Specifications
Rotor diameter: 962mm
Weight: 1.75 kilograms
Length: 835mm
Height: 270mm
Motor: 500 watts
Gear ratio: 8T, 9.75:1:4.286; 9T,
8.67:1:4.286
Construction: Carbon fiber (optional
G10 frame)
Control system: CCPM 120° swashplate
Drive system: Belt-driven tail rotor
Main rotor blades: 420mm main,
70mm tail
Tailboom: Oversized, aluminum
Canopy: Factory-painted fiberglass
Landing gear: Multipart plastic-andaluminum
assembly
Battery: 14.4- to 22.2-volt Li-Poly (6S
recommended)
Requires: Six-channel helicopter radio
system, gyro, digital miniservos
Price: $499.95 ($459.95 for the G-10
version)
12sig2.QXD_00MSTRPG.QXD 10/23/09 9:45 AM Page 44
The Atom is sleek and low-profile. Part of
that look comes from the absence of tailboom
supports. That echoes one of Compass
Model’s major goals: to offer performance
helicopters with low parts counts.
Because the powder-coated aluminum
tailboom is large in diameter, it’s good at
withstanding loads without the support of
additional bracing. To keep the boom itself
from twisting, it’s keyed into the frame and
tail cases. Once snugged into position, it
doesn’t so much as shimmy.
Play (in the fit of parts) is expected with
a helicopter; however, after a season of
flying my Atom 500, it doesn’t have one bit
of slop, or play, in the parts. That includes
the programmable head.
When assembling the machine, I had to
remove the prefitted linkages and size them
because they were so tight. They’re still
slightly on the snug side. Electric helicopters
don’t get lubricated as glow-powered
helicopters do, so from time to time the
Atom’s swashplate, sliders, and links get a
touch of lubricant.
As mentioned, the model came
assembled with even the motor installed,
with the stock nine-tooth pinion. The
disappointing part about the Atom’s being
an ARF is that enjoying the engineering
majesty is left for later, when maintenance
or repair is needed.
The main shaft is stout, 8mm thick, and
fairly short. The stepped drive gear has
heavy teeth that withstand torque from the
high-output motor and jumpy throttle
changes I have asked of it.
Still, its inner supportive webbing is
light, which is good for when the ground
impacts it improperly. That part will gladly
sacrifice itself, to save more valuable (and
expensive) parts of the drive system.
I downloaded the instruction manual and
highly recommend spending the ink if you
have a color printer. I found no
complications with the manual other than
the occasional hardware-dimension
variation. The good thing is that long bolts
can easily be shortened.
It was considerate that Compass thought,
as I have, that installing the servos before
everything else on the frame makes that part
of the job easier. It’s less awkward.
To prevent the belt from slipping, keep
play in its tension to a bare minimum. I can
barely flex mine between the main gear and
the pulley tensioners. Condition the belt
with WD-40 on a regular basis.
Without boom supports, there’s no place
to mount a horizontal stabilizer. So Compass
left that part off. Most 3-D pilots remove the
stabilizer anyway, because it creates
unwanted drag in flips.
As are the frame sides, the vertical fin is
robust. I have yet to see it shake even a little.
The fin is a bit short, though.
If you’re careless, a tilt on the ground
can quickly modify the stock plastic tail
blades so that they’ll fit on a 450-class
machine. I thought the stock blades were too
flexible anyway. The KBDD blades on there
now work great.
The sleek fiberglass canopy is just large
enough to cover the recommended 6S 2600
mAh Li-Poly battery. I found batteries that
were a really tight fit, but the Common Sense
2600 35C that came out recently is a homerun
match for this machine.
Regardless, 25C batteries are the lowestrated
packs to run in this machine. It demands
low-resistance power, and, as the pilot, you’ll
want that power available.
My prepainted canopy has the old color
scheme. As it would arrive today from
Common Sense RC, the redesigned canopy
has more yellow than white. Both are
attractive. The molded-in grommet and
Delron lower bracket mount locations were
spot-on.
A long-range radio system is required for
this class of machine. I like the Spektrum
DX6i transmitter’s simplicity, and the smooth
throttle and switch locations suit my tastes.
The Atom includes servo arms that are
sized appropriately to achieve the correct
geometry with the swashplate. Two sets are
provided; one for JR and one for Futaba servo
users.
Something I would like to see revised on
future Atom 500 kits is the flybar. The
independent flybar stabilizer arms lock on
with a grub screw. A precision-machined flat
at the arm location on the flybar would not
only aid in alignment, but would also ensure
the accurate orientation of the arms.
I know I claimed that the Atom 500 was
named for the size of blades it uses, but the
recommended size is 420mm-430mm—not
500. That’s silly, huh? I don’t make the rules;
I merely report them.
Available from Model Rectifier
Corporation, MAH makes some of the finest
carbon-fiber helicopter blades on the market.
Visit a dealer to get yours.
The 420mm MAH set on my machine is
balanced and beautifully finished. I haven’t
had the need to test a set of 430mm blades,
but I suspect they’ll add to the stability of an
already well-balanced machine.
As for experimenting, I played with
batteries, tail blades (had to), and paddles.
KongPower has a very light 25C 2600 mAh
6S pack that’s great for sport-flying. It got
hotter than the rest when I pushed it.
The heartiest battery I tested was the RFI
3200 mAh 6S, which also has a 25C rating.
Available from Model Rectifier Corporation,
this pack tipped the helicopter off of its CG
fun spot but couldn’t get hurt, no matter how
hard I flew.
So far, I’m happiest flying the Atom with
a 2600 mAh 35C 6S pack from Common
Sense. I don’t know if it’s custom-made for
this machine, but it ought to be. Expect flights
to last four minutes if you’re a mean 3-D
pilot; five minutes if you’re learning 3-D; six
minutes if you can fly, loop, and stuff; or
eight minutes if all you’re up to doing is
hovering around.
Flying the Atom for the first time gave me
that “OMG!” feeling. As I mentioned, my
practice with electrics came from 450-class
machines.
The Atom 500 is a Cadillac by
comparison, but with Corvette
performance. The head speed and power
was scary at first, but that’s the way these
machines are and I quickly got used to it—
also known as “spoiled.”
Forward flight requires a touch of
forward trim, but that’s because it’s
missing a huge stabilizer, as is seen on
F3C helicopters. The Atom is rock solid in
a hover, as if I’m flying a 30-class glowpowered
helicopter. When gusty
conditions spin up, I never hesitate to fly
the Atom; it hardly notices the wind.
I have approximately 12° of pitch in
both positive and negative curves. I can
feel the bite the power of the machine has,
and full collective is unnecessary to
appreciate that point.
Tick-ticks are my new showstopping
routine, because the Atom has the “pop” to
arrest any approach angle. I get more
aggressive with the model every time I fly it.
Back to the experiment thought, my
latest “like” is the new paddles from
KBDD (Compass helicopters’ previous
distributor). That company makes the only
replacement upgrade paddles, since the
2.5mm flybar is unique. The paddles
smoothed out the Atom but took away
none of its authority. And their bright
color makes the machine a little easier to
see.
When you’re learning, or even if you’re
great at flying helicopters, service and parts
availability is paramount. Don’t panic
because Compass Model has been passed
around to different US distributors;
probably at least 100 dealers here carry
parts for this line. I don’t think anyone will
be disappointed with the Atom 500. MA
Michael Ramsey
[email protected]
Manufacturer/Distributor:
Compass Model/Common Sense RC
9725 Owensmouth Ave.
Chatsworth CA 91311
(866) 405-8811
www.commonsenserc.com
Sources:
KBDD LLC
(614) 863-1111
www.kbddintl.com
JR
(800) 338-4639
www.jrradios.com
Spektrum RC
(800) 338-4639
www.spektrumrc.com
Model Rectifier Corporation
(732) 225-2100
www.modelrec.com
Other Published Reviews:
None known at time of publication