been a few months now since I decided I wanted to start flying model
aircraft again, after about a lapse of 10 years. Fortunately this
time the web was around to help with, what was going to be, quite
pretty sure what I wanted to try: Electric gliders.
My previous flight experience was with pure sailplanes, and the 'new'
electrically powered flight without the hassle of glow engines, looked
electric glider I could buy in South Africa was a two meter T-tail,
600 engine powered glider. The flying experience left me disappointed.
The glider was very underpowered, and exhibited a very bad wing stall
characteristic when doing low speed turns. With the low engine power,
takeoff was a hassle, and you could not actually try turning without
fearing a stall. No need to mention this recipe for disaster turned
out to be one!
doing research on the web to figure out how to modify the 'flying
pig' by adding ailerons, I came across a review of the Filip 600.
The beautiful lines of this plane immediately caught my attention.
It took me a very short while to find out that it is not available
in shops locally, so I started looking at various online hobby shops
and other online reviews of the Filip 600.
the Filip 600 on Hobby-Lobby
(more about them later) in the USA, and was on the verge of ordering
the Filip 600 from them, when I saw a mention of a 'Sport' version
of the Filip on one of the discussion pages. One of the reviews I
had found, mentioned a wing flutter that the Filip 600 experienced
during a high speed dive. I was not really worried about the flutter
itself, because I knew that thermal sailplane wings are not designed
to do high speed dives. The Sport version of the plane had very stiff
foam wings, that were covered in balsa and Oracover. The result is
a very stiff by lightweight wing. The plane I was looking for had
to be a hybrid that could do a bit of thermal soaring but also loops
and rolls with the worry of the damaging the wings. A quick reply
to an e-mail sent to Hobby-Lobby informed me that they unfortunately
did not sell the Sport version.
search with all the best web search engines revealed very little extra
information about the Filip Sport - unfortunately no reviews. I found
a few pictures on one or two Czech sites, and came across the manufacturers
site: RCM-Pelikan. The most
important find I made however, was Puffin
Models (more about them later as well) in the UK. A quick e-mail
reply from John informed me that, not only are they the UK RCM-Pelikan
agent, but also has a Filip 600 Sport in stock.
bits of kit that I would need to complete the Filip, was the power
and remote control systems.
clear very soon that for the high performance plane I was looking
for, the engine choice was between the ModelMotors
AXI 2820/10 and the Jeti Phasor 30-3. Both are brushless motors. I
went for the ModelMotors AXI engine because it is extremely light
for its size and power. The brushless controller was a very clear
choice of the Jeti 40-3P with BEC. The engine would be powered using
8 Sanyo 2400 mAh SCR cells.
spinner and CAM blades was a bit of a tough search again - there are
a lot to choose from . Eventually I decided on the 40 mm Turbo spinner
used with many RCM-Pelikan models. It allows engine cooling through
a hole in the front of the aluminum spinner. According to a number
of reviews the CAM blades to use were the Aeronaut (Freudentahler)
12x8 8mm carbon fiber type blades. According to the specifications
of the AXI motor using smaller blade sizes like 11x7 would be more
I wanted I managed to buy locally. I decided on the JR X-378 because
it is good value for money, and it supported a sailplane flying mode.
I did not use the JR servos because of their size, but found in the
many Filip 600 reviews that the favorites were the Hitech HS-81's
for the ailerons and the Hitech HS-55's for the V-tail ruddervators.
Both the Hitech servos have very good speed and torque numbers, considering
their weight and size.
thanks to all the people before me who put their efforts and experience
on the web for me to use. I hope to do the same for someone that comes
across my page and find it useful.
be said, both the online retailers I have used so far impressed me
very much. I all cases I had very quick responses to e-mails sent,
care taken to ensure that delivery is on time and that I am happy
with the end result. The whole ordering process ended up being a very
international affair, with my completed airplane coming from 3
different continents. What really caused me the most gray hairs,
was the currency exchange rate differences between Europe and the
US. Due to the different rates for British Pounds and US Dollars,
the US was the cheapest option in most cases.
above, the Filip 600 Sport was ordered from Puffin
Models in the UK. Puffin Models retails in models from RCM-Pelikan
that I could find on no other English language website, and also stocks
a lot of other
components. After badgering John
with a lot of questions via e-mail, to which he replied promptly every
time, I ordered the following from him:
600 Sport Electric V-tail
the transit from the UK to South Africa, the package (clearly marked
as 'Fragile'), must have been
dropped somewhere. The package was made up very well, but the underside
of the box had a hole about 20 cm in diameter in it. Whatever made
the hole punctured the plastic bag with the spare components, and
also broke the wingtip of one of the wings.
John immediately to sort out the problem. John offered the option
of a cash refund to repair the damage, or to send a replacement wing.
I decided on the wing replacement. Now what followed is the real amazing
part, and Puffin Models really earned my respect. John not only replaced
both wings for free (I think because the colors were slightly different),
but also had them on my doorstep within 3 days! No need to say, I
am a very happy customer.
600 Sport kit included the fiberglass fuselage, wings, V-tail, pushrods,
control horns, screws and other components. The ailerons and ruddervators
were already attached with hinge tape, and I saw no reason to remove
them. The kit also included instructions for assembly and a very good
checklist for the glider version of the Filip to calibrate the handling
characteristics. The worked equally well on the electric version.
of the components were ordered from Hobby-Lobby
in the US. These guys also proved to be on top of their game. They
have a wonderful website with a very large
range of products (most with photos and complete pricing details).
The one reason why I was so content ordering all the components from
one supplier was Hobby-Lobby's great Low
Price Guarantee. It basically says that if you can find any other
US online retailer where the same product is cheaper, they will beat
the price by 10% if the other guys have stock or match the price if
they don't have stock. This is where my research on the web paid off
- I knew where the cheapest components were sold. In the cases where
it applied I supplied the details with my order to Hobby-Lobby. Don,
a salesman there replied very quickly with: 'I appreciate the opportunity
to match these prices'. Here is the order I sent them:
Motors AXI 2820/10 rotating can brushless motor
JES 40-3P Controller (with BEC)
Cell Sanyo CP-2400SCR NiCad pack
Aeronaut CAM Folding Prop pair (carbon fiber)
Turbo Spinner for 5mm shaft
HS-81 Sub Micro servo (JR connector)
HS-55 Economy Sub Micro servo (JR connector)
Servo extension for JR or Hitec
Clear Hinge Tape, 32 feet
again the package was delivered in very quick time (approx. 4 days).
The package arrived well packaged with absolutely no damage to the
with both retailers mentioned above, makes me very confident to recommend
them to anyone even (or especially) if you live in the UK or the US.
Well done guys!
the assembly by fitting the wings to the fuselage. I followed the
instructions, and drilled two holes in the fuselage where the leading
edges of the wing roots meet the fuselage. Two hardwood dowels epoxied
into the leading edges of the wings slot into these holes keeping
the wings firmly attached. The sturdy metal wing joiner required no
additional work and fitted exactly into both wings.
dowels that come with the Filip kit are about 2 cm long. I found
that by replacing them with ones that are at least 5 cm long,
the chance of damage to the wing on a rough landing is reduced.
The shorter dowels are glued only to a short portion of the leading
edge that is unable to handle larger forces. Increasing the length
spreads the forces over a larger part of the wing root.
are secured with two nylon bolts. These bolts are designed to shear
off in case of a crash or hard landing. The bolts fit into blind nuts
that are embedded in a piece of plywood epoxied inside the fuselage.
Two additional holes need to be drilled for the bolts to pass through.
holes in the wing where the nylon bolts pass through, has a plastic
plug on the top part of the wing, but the rest of hole runs through
wood. I found this design not to be strong enough to shear the
bolts when needed, but to rather damage the wood. To solve the
problem I strengthened the holes by putting aluminum tubes in
them that are epoxied in place. The aluminum shears the bolts
instead of breaking the wood.
the plywood engine mount was very straight forward. I sanded the nose
of the fuselage down, so that the spinner and the nose are the same
size. The circular piece of wood is slightly oversize, and after sanding
it down a bit, it fits tightly about 3 mm from the front of the nose.
I first used a bit of CA to keep it in place and then epoxied it very
tightly in place from both the inside and outside. The mount plate
was installed with a bit of down and right angle.
was bolted into place with two bolts. I tried to position it so that
the ventilation holes match up with those on the motor.
confused me for a while, figuring out how exactly it is fitted onto
the fuselage. Two fiberglass strips are glued to the inside front
and rear of the canopy. I used an epoxy that remains fairly flexible
after curing and this proved a very good choice after one or two harder
landings. To fit the canopy the rear is slid on first and then moved
backwards. It is possible to move it back so far that the front can
clip on as well. The canopy is then moved forwards until it fits tightly.
I normally secure it with a bit of Scotch magic tape to ensure a tight
and smooth fit.
installation was where I probably deviated the most from the assembly
instructions. Most of the changes were done after I had a few flights
under the belt already. The most important fact to remember regarding
the battery is that it is a 1/3 of the flying weight, but in very
compact size. Under conditions of quick deceleration, the battery
has a lot of momentum, that you want to get rid of without causing
damage to the plane. Because of its weight it affect the CG depending
on the position inside the fuselage.
the problem of dissipating the momentum of the battery, I replaced
the supplied plywood battery tray with a pure balsa one. The think
is that in case of a crash I would rather have the battery tray break
and absorb energy, than to expect the fuselage to do so. Secondly,
I also changed the position and size of the spruce lattice that supports
the tray. Again the thinking is that it should rather break than go
through the fiberglass. The change in the position of the lattice
is to avoid the situation where the wood can act like a wedge and
crack open the fuselage. By placing the lattice lower in the fuselage
it could be shorter in length, so that when it comes loose, it is
unable to wedge in anywhere.
modification was made to the battery tray. Normally the tray is supposed
to be screwed to the spruce lattice, but I decided to rather attach
it with Velcro. This had two main advantages: firstly it allows to
tray to be moved forward or backward with relative ease - very easy
to adjust the CG between flights, and secondly it could also come
loose easier in a crash - again to minimise damage. The Velcro that
is used to keep the battery in position overlaps about 1.5 cm only.
The reason is that if too much of the Velcro overlaps the bond is
too strong. In an actual crash, that battery stays connected to the
tray and could cause damage.
the wires away from the rotating can of the AXI 2820/10 motor
can be a bit of a problem. To those unfamiliar with the type of
brushless motor, the AXI motor has a rotating can on the inside
of the fuselage that is connected to the motor shaft. The is done
to achieve a tremendous amount of torque from a relatively small
motor. The problem is inside the fuselage because the three wires
that is connected to the speed control could touch the motor while
the motor is running. To get past this problem, I used a 3 cm
piece of piano wire, made a small V shaped bend in it, and epoxied
this to the inside of the fuselage. The wires could then be fixed
to the fuselage with a cable tie.
the speed controller was a straight forward task. I soldered the three
supplied gold plated connectors to the engine wires and the speed
controller wires, and insulated them with heatshrink.
the RCM-Pelikan guys designed and build the fiberglass fuselage
they did an excellent job. I had a few rough landings since mainly
because my flying field has a few areas lately where the grass
was about 1.2 meters (4 feet) tall. When a wing is caught by long
grass there is not much you can do. The front part of the fuselage
developed a few cracks that indicated there were a few areas that
required strengthening. I bought a piece of woven fiberglass cloth
but instead of using resin, I expoxied the cloth to the inside
of the part of the nose and around the area where the wing roots
are fixed to the body.
installation was started by connection all the electrical systems
with extension wires to make sure that there were no defective components.
This also provided an opportunity to zero all the servo positions
before they are installed.
not to follow the V-tail servo installation instructions. The long
pushrods were very thin, and gluing the tube to the inside of the
tail did not look easy. The Hitech HS-55 servos are a perfect fit
in the tail. The total height of the servo is less than the width
of the opening across the tail, and both servos fit in there very
the holes in the tail first before the V-tail is attached. It
makes the drilling and sanding a lot easier.
horns for the ruddervators were attached so that the piano wire control
rods are parallel to the tail. I used the supplied plywood mount to
strengthen the tail internally. Cut into two pieces the plywood was
epoxied inside the tail aligned with the existing holes. I made sure
before they were glued in place that the HS-55's fitted nicely.
were installed with the servo horns in a forward position. This ensures
that there is a greater upward movement of the ruddervators compared
to the downward movement. The piano wire was cut to length and bent
in place. Any additional trimming could be done via the radio's travel
adjustment and zero settings. The radio also has a built-in V-tail
mixer so that no external mixer was required.
V-tail in the kit is already glued together at the correct angle.
Some reviews I read suggested strengthening the bond - and even
more so for a semi-aerobatic plane. After the V-tail was epoxied
to the fuselage, I removed a 1 cm string of Oracover over the
middle part of the V-tail joint. I epoxied a 1 cm strip of woven
fiberglass in place directly on the balsa. The V-tail stiffness
was immediately improved.
was wrapped in foam rubber, the antenna pulled through the tail and
out the rear opening. I shortened the servo extensions running to
the rear servos, soldered the connections and put some heatshrink
over the connection. I installed the receiver behind the battery in
the tail. It is out of the battery's way in case of a hard landing
and also helped with the final balance to get some weight in the tail.
are prepared for the aileron servo, by removing a precut circular
hole under the wing. After removing the inner foam core until the
top wing covering is reached, the hole is ready to be cut to size.
I made the hole an exact fit for the HS-81 servo. The servo extension
is run through a tube that is already in place. I cut the extension
to size and soldered it directly onto the servo.
to strengthen the servo hole adequately. By removing the material
from the wing to fit the servo the wing is weakened. I modified
the wings after the first few flight with epoxy and woven fiberglass.
not use any servo mounts in the servo bay, but wrapped the servo in
Scotch Magic tape and CA glued it in place. CA and Magic tape really
works well and the servo never came loose ever. It is removable though,
and it is very clear when you eventually have to remove the servo,
that the CA bond is a strong one. Make sure that according to the
instructions the servo horn is slightly towards the front of the wing
in the 0 position. It helps in setting up the aileron differential.
the suggestions in many reviews I used the supplied aileron horns.
They are the exact size and shape that is required. They were epoxied
in place after preparing the aileron by drilling 3 holes in the correct
places. I inspect them regularly, and they haven't shown any signs
of coming loose.
Scotch Magic tape to secure the supplied servo covers over the
aileron servos. The covers are easily cut to size.
the Filip was ready for the first test flight. I fully charged both
my 8 cell batteries as a show of blind faith. The new NiCads required
an initial slow charge of about 15 hours each, so I started well in
advance of the planned flight.
up / 7mm down
up / 8mm down
aileron differential, spoilers (ailerons both up 19mm) & -6%
elevators, +15% rudder with ailerons
flight was very nerve wrecking (as I suppose many first ones are!).
After doing the preflight check about 5 times, the Filip was as ready
as it could be. I had an idea how powerful the AXI motor with the
Aeronaut blades should be in flight, after reading articles and balancing
the prop at home.
out I had no idea!
not to take any chances, I opened the throttle to 100% and launched
to Filip with a strong throw at a slightly upwards angle. It climbed
cleanly without hesitation at the shallow angle of the launch. I pulled
back very slightly on the elevator, and the angle of ascent increased
without faltering. I was totally amazed at the power of the climb.
(Subsequent flights showed that almost vertical climbs can be achieved
when the battery is still fresh).
about a minute of climbing at the same angle, with only small adjustments
to keep the wings level, the Filip was incredibly high. I leveled
off and throttled back to zero power. As soon as I started the first
test maneuvers, it became very apparent that the Filip was extremely
nimble but true in flight. The 'Sport' version is very precise and
the aileron response is immediate and predictable.
the landing approach the spoilers proved invaluable. The Filip just
keep on flying when you get close to the ground, so using the ailerons
as spoilers help in bleeding off energy, without running the risk
of stalling the aircraft.
so far have been very enjoyable. It behaves very well in a variety
of weather and wind conditions. Flight times of 20-45 minutes are
easily attainable. It is a plane I can very easily recommend!
spare a thought for my wife who had to endure about a week of this
mess on the dining table!