this would be a loud cheer for a sports team, but in this
column, "Go Panthers!" is all about EDF. If you're
a fan for those early jet designs from the 1950s, you can
build or assemble your own electric-powered F9F Panther from
numerous types of materials.
addition to the many ARF designs currently on the market,
you can still find kit versions or plans available if you
prefer to build. New, lower-cost EDF components are providing
incredible power levels in any size R/C model.
this month's issue of AMP'D, we'll assemble several different
types of Panther models ranging from lower cost foam designs
to a higher-end German-engineered fiberglass model that will
Materials for Models
R/C models are now being made from many different materials
that vary in weight, strength, thickness, and cost. Here is
a brief description of some of these materials and their properties.
a distance, you often cannot tell what materials some models
are made from until you actually get closer or hold them in
Foam - Sometimes called "cooler" foam as it
is a similar material to the inexpensive beverage coolers.
Although very light and inexpensive, the foam dents and
Foam - This foam is a higher density than the EPS foam.
The smaller cells provide a smoother finish. Although it
is slightly heavier, it resists dents and scratches.
Coated Foam - A revolutionary new PolyCarbonate (PC)
process that provides a hard 0.3mm shell finish over foam.
It won't dent, break, or shatter. The PC is a lightweight
coating that is lighter than fiberglass and adds durability
to foam never seen before. The smooth glossy finish can
be painted without surface preparation with a result that
resembles a fiberglass model but has a lower cost.
Composite - Fiberglass is material made from extremely
fine glass fibers. It is used as a reinforcing agent for
many polymer products where the resulting composite material
is known as fiber-reinforced polymer (FRP) or glass-reinforced
plastic (GRP). The Aeronaut F9F Panther that I assemble
in this column uses GRP which is commonly referred to as
fiberglass. Thermosetting plastics are normally used for
GRP production, most often unsaturated polyester but vinylester
or epoxy is also used. As with many other composite materials
(such as reinforced concrete), the two materials act together,
each overcoming the deficits of the other. GRP becomes a
material that resists both compressive and tensile forces
well, making it a superior lightweight material for model
aircraft. This superior material, when properly made, comes
with added cost.
- A classic built up balsa kit of the F9F Panther is available
Kits. The kit contains all cnc cut wood parts that provide
an accurate fit of lightweight easy to assemble components.
The wood kit is complimented by vacuum formed tip tanks,
canopy and nose cone. The RBC Panther model is similar in
size to the Aeronaut F9F Panther but they are completely
different in construction and targeted at different customers.
While built-up wood kits are generally light weight and
less expensive, they do require a higher level of craftsmanship
Shenzhen Lander Technology Company
Shenzhen Lander Technology Company (aka RC
Lander) is an innovative organization that makes R/C models
and accessories. Based in Shenzhen, China, the group has 50
employees and two floors of factory area around 1,800 square
meters in size.
Lander specializes in EDF systems and has developed a reputation
for exciting products.
of the owners of RC Lander is Designer and Engineer, Tim Wan.
Tim is well known in the R/C industry and has over 20 years
of experience flying models from nitro-powered planes to EDF
jets and helicopters.
has designed many great looking Panther and Cougar models.
They not only look great but they fly extremely well and come
with many accessories like flaps, retracts, and working wheel
doors. Here he is posing with a new 90mm PC coated foam MIG-17
design soon to be released.
Lander has some exciting new designs for 2010 that include
different materials and larger 90mm and 120mm power systems.
RC Lander PC Coated Panther
RC Lander products are now available at Nitro
Planes. RC Lander did a good job with their packaging as
each part was wrapped in protective foam and the box was divided
into compartments that matched the size of the parts. There
were no smudges on any of the parts or on the glossy PC covering.
The Panther kit even included little bottles of part A &
B epoxy in the parts bag. An all metal RC Lander 70mm EDF with
balanced rotor is also included.
PC version comes complete with the ESC and CBEC already soldered
up with pseudo-Deans connectors on the battery side and gold
pin connectors on the EDF side. The kit also includes a pre-soldered,
ready-to-use series connector if you want to use two 2s packs
in series instead of a single 4s pack.
the wing (left below), the ailerons and flaps are pre-hinged
and the servo pockets come with color coded PC covers. Before
I knew it, I had the servos installed, the covers in place,
and the control rods adjusted.
RC Lander all-metal suspension strut gear system (with doors)
comes completely installed with the servos and control rods
already in place. However, there is some tweaking necessary
to finalize the correct action of the retracts and doors.
door covers for the gear mains are attached to the struts
and then the wheel doors close after the mains are in their
pockets. The cover action is controlled by fishing line attached
to custom designed servo horns. Everything is adjustable as
shown in the photos.
nose wheel steering uses its own servo, which is also pre-installed.
I mixed the nose wheel steering to the rudder channel with
my Spektrum DX-7 transmitter.
RC Lander all-metal suspension landing gear (available as
an option on all of the other models; standard EPS and EPO)
are an excellent value.
tail section required the horizontal stabilizer to be glued
in the pre-formed slot on the vertical stabilizer. The elevator
comes factory installed but the rudder needed to be hinged in
place. I used ZAP-O Foam-Safe CA to glue these areas. Next,
two servos were placed in their pre-formed pockets after first
covering them with masking tape. The servos were then installed
using hot melt glue, so if needed, they can easily be replaced
or repaired. Two 12" servo extensions were attached, one
to each servo, and the tail feathers were glued to the fuselage
using the supplied epoxy.
the control rods were attached to the aileron and flap servos,
the wing surfaces were tested. The wiring in the wing bay
was cleaned up and the extension connectors were hot glued
in place to keep it neat.
Tim Wan did some great design work with his new all-metal
EDF units. Included in the PC coated version was the new EDF
with 6s capable 2399Kv inrunner motor and balanced rotor.
The unit produces 4lbs of thrust when drawing about 60 amps
of current. The gold pin connectors were already soldered
onto the motor wires.
EDF unit was connected to the ESC/CBEC system and became a
drop in fit. The cover fits like a glove and only two screws
are used to keep it in place.
electronics bay was cleaned up because there were wires that
needed to be kept out of the way of the retract mechanism.
I like to label each servo lead wire that gets connected to
the receiver so you can always plug it in with confidence.
The Panther looked rather "naked" without the decals
applied in the top photos. Even after they were applied, I
decided that the panel lines needed to be more visible. I
found some permanent, fine point markers at Michaels (or AC
Moore) in an assortment of colors. A dark grey was used to
fill in the molded panel lines which resulted in an almost
natural weathered look.
did a video to show the action of the retract system and the
covers. It actually works quite well although the mains had
a tendency to bounce when the plane was inverted for the video.
F9F Panther fiberglass EDF model was designed after the
Grumman F9F-5 Panther. The decals supplied in the kit (125183
/ WL-25) displayed the markings of VMF-311 (Marine Fighter Squadron
311) which was based in Pusan, Korea in 1952 during the Korean
War. Originally constructed as an F9F-4, the jet was completed
as an F9F-5 before delivery and is now displayed
at the Pima
Air and Space Museum on loan from the National
Museum of Naval Aviation. The F9F-5 was effectively an F9F-4
with the stretched fuselage and taller tailfin, but with an
improved derivative of the Nene turbojet, known as the Rolls-Royce
The Aeronaut model has a 52" wingspan and weighs about
7-8lbs when flying. It is an all fiberglass ARF with German-engineered
quality which is the best I have seen to date. It sells with
and without retract bays for about $700 at Icare
RC and Ductedfans.com
in the U.S. and at WeMoTec
original release of the Aeronaut Panther in 2003, which is
what I have, did not have landing gear bays or cutouts in
the fuselage. It took off from grass using only 700 watts
on 16-20 NiCd cells. It could cruise around on only 200 watts
in low wind conditions or speed up to over 100mph. The second
release around 2007 had gear bays, cutouts, covers, and a
power system for the Aeronaut Panther would use newer technology
components along with the proven high-quality WemoTec Midi
Pro 90mm ducted fan with its dynamically-balanced rotor. I
have used this fan on previous projects with up to 3300 watts
36-75-1 Motor - The ARC 36-75-1 inrunner motor is designed
for high-power EDF applications. It is distributed in the
U.S. by LightFlight
RC and can deliver up to 2700 watts on an 8-cell LiPo
pack for only $130.
ICE 100 ESC - The new Phoenix ICE100 ESC from Castle
Creations can supply 100 amps with up to an 8-cell LiPo
pack. It also features a programmable 5-amp switching BEC
for maximum servo power that can be set from 5v to 7v in
0.1v increments. The light design weighs only 2oz and has
built-in Data Logging for only $140.
Midi Fan Pro - The WeMoTec Ducted Fan for 5mm shaft
brushless motors has a dynamically pre-balanced rotor for
vibration free power. The 93mm outside diameter ducted fan
comes with all the parts shown from Hobby
Lobby for only $75.
LiPo - These new "Blue
LiPo" batteries from Hobby
Partz come in many size capacities, cell counts, and
discharge ratings from 15C to 40C. I'm using two of these
4s, 30C, 4000mAh packs in series to provide a powerful 2700
watts in my Aeronaut F9F Panther.
of the Aeronaut Panther parts can be dry fit together right
out of the box. I was most impressed with the quality of the
fiberglass material as it was both light and strong. All the
glue joints used aircraft-grade epoxy and they were very solid.
The precision fit of the wings and tail were simply incredible!
designer added SpringAir 602 retracts in 2007 but my original
version without them was from 2003. I didn't mind because
I fly off mowed grass fields and I knew that this Panther
design would have no problem with it. In 2008, Aeronaut also
released their own version of the SpringAir 602s and a new
90mm carbon fiber fan called a TF-2000 that handles bigger
motors up to 3000 watts. Since I knew that the Wemotec Midi
Pro fan can handle 3300 watts, I saw no need to buy an expensive
carbon fiber fan unless you really wanted some weight reduction.
My version of the Panther would already be lighter without
tail piece comes ready to mount to the fuselage so the builder
need only glue the horizontal stabilizer and install a servo
and linkage for the elevator halves. A template is provided
to make an accurate opening for the stabilizer.
also decided to cut a working rudder which had to be done
in two halves. I used strong digital Futaba S3150 servos that
would return to center accurately. Since I did not have sufficient
room for clevis adjustment at the control surface, I was able
to streamline the connections to the elevator and rudder halves.
I used Sullivan Heavy Duty Pushrod Connectors on the servo
arm for zero wobble.
wanted a pull-pull rudder system on both halves but didn't
have straight runs for using cable so I used Dubro Micro Pushrod
Systems. By securing the tubing along the way to the servo,
it made for a light and powerful control system. The elevator
halves use much shorter runs of thicker rod and tubing supplied
in the kit. I replaced the stock metal adjustable clevis with
some Dubro 2mm Swivel Ball Links.
may not look pretty underneath but both split elevator and
split rudder now have precise tracking and return to center.
None of the control surfaces had any wobble and the tail section
was much more solid with all the bracing so I was happy with
Wing Servo Assembly
first precision cut on an expensive fiberglass model was made
easier by using a metal ruler for a Dremel tool cutting guide.
A tip picked up from Bob Ruff via Carl Rich. The two wings
on the Panther were assembled using the same technique.
first marked the position of the servo on the wing bottom
and then boxed the area using masking tape. I decided to use
less expensive Futaba S3115 micro servos for the aileron control
since each aileron required a servo. The 0.80oz micro servo
was a perfect size for the thin wing and provides 39oz/in
torque on only a 4.8v supply. The servo was positioned inside
the wing and held in place with epoxy. I used the stock hardware
for the control linkage and glued the fiberglass cover back
in place after cutting a section away to allow for the servo
arm to swing. A Hobby Lobby (HLH550) Exit Cover was used to
reduce drag and protect the linkage on grass belly landings.
This versatile plastic cover can also be used in the reverse
direction as an air scoop.
seemed every time I touched the finished fiberglass surface,
it made a perfect fingerprint mark. To clean up a plane section
after assembly, I used a debonder on the tough stains and
then wiped the wing using nail polish remover.
EDF and ESC Mounting
decided to mount the wings in my Panther as the last step
just before applying decals. It was much easier to work on
the main fuselage area without the wings being in the way.
using the Wemotec DF, instead of the Aeronaut TF-2000 DF,
you need to mount the fan your own way. The stock Aeronaut
TF-2000 DF uses a ring mount technique and mates with three
blind nuts already mounted in the firewall. The carbon fiber
TF-2000 DF is very expensive compared to the Wemotec Midi.
The dynamically balanced rotor of the Wemotec Midi fan makes
it the best quality standard on the market for a reasonable
price. I already knew it can handle over 3000 watts from my
previous Predator UCAV project.
used a set of .60-size glow engine mounts to hold the Midi
DF to the firewall. After first gluing some ¼"
hardwood braces behind the firewall to add support, I mounted
the glow engine posts using hex head screws and t-nuts. Note
the lip from the fiberglass intake ducts fit snuggly inside
the fan. This not only provides efficient air flow into the
fan but also aligns the fan perfectly. The blue masking tape
arrow was used to level the position of the glow engine mounts
as it was difficult to get them perfectly aligned due to limited
access to the firewall. I used thin ply angle brackets to
provide the correction. The result was a very solid but removable
DF mount to the firewall.
Castle Creations ICE 100 ESC was mounted to the left side
intake duct. In this manner, cooling air is forced over the
ESC and I did not have to cut into the perfectly smooth belly
of the Panther.
installing the ARC 36-75-1 inrunner motor, I used an MPI (ACC3939)
36mm heatsink to aid cooling the back half of the motor. This
low-cost aluminum heatsink is a pressure fit and has fins
that minimize air flow disturbance.
exhaust tubing material is supplied in the kit so I cut the
proper size needed for an FSA (Fan Swept Area) of about 86%.
The fan swept area is calculated by subtracting the area of
the impeller hub from the area of the inside of the shroud.
Choking down the airflow at the exhaust, increases exhaust
velocity, which in turn will increase top end speed of the
aircraft. There is, however, a point of diminishing returns:
choking down the exhaust too much will back pressure the fan
resulting in degraded performance. Additionally, a larger
outlet area will increase the static thrust of the system,
but lower the top end speed of the aircraft. Using a value
around 85% produces a good compromise between static thrust
and exhaust velocity. The Aeronaut Panther fuselage was designed
for this FSA value so the exhaust tube was a perfect fit.
installing the ESC, I added about 12" of #10 Castle Creations
wire to extend the leads to the motor. This results in no
extra capacitors being needed on the battery leads. I used
6mm gold bullet connectors that can handle up to 120amps and
need no harness to connect the two 4-cell Blue LiPo packs
the single tywrap to hold the three motor wires together at
the connectors. This keeps them from vibrating in the strong
cockpit is still a work in progress. I really enjoy this part
of any assembly and take some time to make it look good. My
pilot is the ParkZone (PKZ4414)
molded rubber pilot from their T-28. The Aeronaut Panther
kit comes with molded cockpit, seat, and canopy sections that
need to be cut out accurately to mate with the fuselage.
Panther Project Completion
Aeronaut F9F Panther is near complete but will not fly until
winter is over. Sometime this summer, a future issue of AMP'D
will cover the Panther performance with photos, video, and
an internal GPS speed reading.
a larger model is what you are after, there are several
options for making a 72" to 75" span Panther that
flies around 15lbs to 20lbs. Many of the larger 120mm EDF
power systems on the market today (shown below) would make
a great power system for this larger size Panther.
Jets makes a very nice looking composite F9F-2 Panther
with a 75" wingspan. The Panther comes in a variety
of color options and has options available like a scale
landing gear set and cockpit. Note that this model is designed
for turbine power and would need some cheater holes in the
bottom if converted to EDF.
Ziroli has a set of plans
available for those who want to build their own Panther
from scratch. The builder could then allow for a larger
air intake if using an EDF power system. An assortment of
support kits for the Ziroli Panther design is also available
Cutters Inc. All of Kit Cutter's wood is sealed in a
nitrogen purged packaging to preserve the freshness of the
wood and control moisture. The wood quality is the best
that is available.
it is not yet available, a 72" span ASM Panther is
being redesigned by Larry White of Jet
Hanger International. This graceful warbird will be
available for 14lb thrust turbine or EDF systems. The ASM
Panther prototype has a wide speed range including excellent
slow flight characteristics. Flying weight with the E-Turbax
system and 12s 6000mAh LiPo packs is 18 lbs; top speed is
approximately 150 mph.
Larger EDF Systems
with Neu 1527/1.5Y Motor - This 120mm EDF combination
Hanger International provides around 5000 watts of
power for 15lbs of thrust on a 12s LiPo pack. The combined
weight of the fan unit and motor is only around 33oz and
a good value at only $470.
Dynamax Xtreme - The new XPS Dynamax
Xtreme combination uses the proven Dynamax ducted
fan unit with a "Big Screamer" outrunner motor
from Little Screamers. Although the combined weight is
a heavier 52oz, the unit has a wide range of operating
power levels that produces from 11lb to 24lb of thrust
utilizing a 10s to 16s LiPo pack. This unit is also a
good value at only $439.
- This Dyn-E-Max
/ Scorpion motor combination utilizes the proven Dynamax
ducted fan unit with a Scorpion outrunner motor. It can
be used to fly a 15lb aircraft and provides around 4500
watts of power on a 12s LiPo pack. The lightweight combination
weighs only 30oz and sells for only $564.
SM110-45 - The SM110-45 EDF system is the latest from
Stumax Aircraft. These power systems are available in
North America from Performance-EDF,
LLC. On a 12s LiPo pack using the Neu 1527/1.5Y inrunner
motor, the system produces almost 17lbs of thrust at 5000
watts. The fan with motor weighs around 30oz and sells
TJ100HP - The TamJets
TJ100HP EDF system has a new stiffer rotor that can handle
up to 4800 watts of power. It can use a Neu 1515 2Y motor
and a 12s LiPo pack or be set up for other configurations
depending upon the model size. The TJ100HP weighs only
5oz and a mere 18oz with the Neu 1515 2Y motor. The cost
is around $700 with motor and $995 as a complete plug-n-play
assembly that also includes a Castle Creations Phoenix
Lander 120mm Set - The new RC Lander 120mm
EDF set is an all metal plug-n-play combination that
contains the integrated DF unit, 100-amp ESC, and powerful
830kv brushless inrunner capable of running on a 12s LiPo
pack. This new package sells at Nitro
Planes for only $419.
TF-4000 - The Aeronaut Turbo-Fan 4000 comes in two
versions; one for 5mm motor shafts and one for 8mm motor
shafts. The TF-4000 offers high performance and extremely
high-quality carbon construction. With a rotor diameter
of around 120mm, the impeller generates a static thrust
of up to 10lbs, making it an excellent choice for scale
model jets with retracts. The carbon fiber fan unit itself
weighs only about 4.2oz (120g). The DF without 10s to
12s capable-motor costs about $369 at Icare
lower-cost EDF components are providing incredible power
levels in any size R/C model. In addition to the many ARF
designs currently on the market, you can still find kit
versions or plans available if you prefer a good building
you often cannot tell what materials some models are made
from until you actually get closer or hold them in your
hand, you can choose from many different materials that
vary in weight, strength, thickness, and cost to suit your
today's R/C market, the product choices are vast. Established
vendors offer new products that allow you to try something
different with almost guaranteed success, while new vendors
are emerging with technology changes that can satisfy even
the most enthusiastic modeler. I have found that today's
EDF designs are an exciting part of electric flight and
offer many of us a fun way to challenge our spirit for new
you fly electric, fly clean, fly quiet, and fly safe!
thanks for contributions by:
"Papa Jeff" Ring
section of AMP'D covers some of the questions that our
readers have sent in and I thought would be interesting
I like your article on storing batteries, but
I'm a little confused. If a (what we call a 11.1
volt battery) is 11.4 at 1/2 charge, what is full
understandable to be confused because the manufacture
ratings often try to mimic the older NiCd/NiMh
packs using a so-called nominal cell voltage.
A fully charged 3-cell LiPo pack is 4.2v x 3 =
12.6v unloaded. This means that if you measure
a fully charged 3-cell LiPo pack with a voltmeter,
it will read 12.6v when not connected to anything.
If you were to connect the same fully charged
pack to a load and draw a fair amount of current
from it, it would read 3.7v x 3 = 11.1v. The problem
is that the load on a LiPo pack must be much higher
than 0.2C to drop the voltage to 3.7v/cell.
unloaded, the half charge for a 3-cell LiPo pack
is about 11.4v. It is easier to read the voltage
of a LiPo pack with a voltmeter when it is not
connected to anything but this voltage will drop
once loaded by a receiver or servos or motor.
full functioning canards and 360degree thrust
vectoring, the Eurofighter lets you perform maneuvers
that aren't possible with other jets. And, like
all other eRC products, the Eurofighter is packed
with modeler-pleasing extras like a detailed cockpit,
Midnight Flyers LED light set and retractable
landing gear with suspension. If you're looking
for a super responsive jet that'll challenge your
flying skills, then the Eurofighter is for you.