RCU Review: GWS Tiger Moth 400

 RCU Review: GWS Tiger Moth 400 More On This Product
Research Airplanes Research Boats Research Cars Research Helicopters Research Engines & Motors Research Radio Equipment Contributed by: Greg Covey | Published: May 2004 | Views: 96870 |
Flight Report
Scale Changes
Manufacturer & Distributor
3401 Airport Drive
Torrance, California 90505
Telephone 310-891-3339
Toll Free: 866-FLYGWS4
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The new GWS Tiger Moth 400 is a larger version of the popular
GWS Tiger Moth slowflyer. It has a geared Speed 400 motor,
real semi-symmetrical airfoil wings, and full-house controls for
ailerons, elevator, and rudder. The heavier, more powerful Tiger
Moth 400 can fly in light to moderate wind conditions.
The kit comes complete with a geared GWS EPS-400C Speed
400 motor, mating GWS 10x6 prop, GWS clear foam-safe glue,
and clay for balancing the model in flight. An optional GWS float
set easily converts the Tiger Moth 400 into a water capable
flyer! See the Tiger Moth 400 in action
Ease of Assembly
Aerobatic ability
Great scale looks
Full-house controls
Semi-symmetrical wings
Plenty of power
Excellent flight performance
Manual errors Length: 781 mm ( 30.7in) Wing Span: 960 mm ( 37.8 in) Wing Area: 27.4 dm² (424.7 sq.in) Flying Weight: 500~550g (17.6~19.4 oz) Wing Loading: 18.25~20.1 g (6~6.6 oz)/sq.ft Power System: EPS-400C(D) Propeller: EP1060 Battery Required: 8N730mAh(NI-MH) Servos: 3 PICO / NARO Receiver: R6NII Speed controller: ICS-400 Radio Required: 4-Channel radio The GWS Tiger Moth parts are
bagged in appropriate sections
The foam wings have a
semi-symmetrical design
A colorful manual and decal
set are included in the kit
Shown above are the Tiger Moth 400 parts just removed from the box. I found no damage on any part
and each of the various types of pieces were bagged in their own categories. The geared Speed 400
motor and 10x6 prop are included in the kit along with plenty of hardware and some clay for balancing
the model. Initially, I discovered that the wings were a real semi-symmetrical airfoil and not just another
undercamber design. I then discovered that this model had full-house controls for rudder, elevator, and
ailerons! Lastly, I realized that the yellow paint did not come off easy or flake like on the film coating on
the smaller slowflyer version. The parts could be handled without hurting the finish. I was immediately
pleased with this new design.
The kit comes with a full color manual and two decal sheets. The second decal sheet is various "GWS"
cutouts. The manual has great photos and instructions that follow the text by number. I have found a tube
length error and some orientation issues that I will cover later in the review. Overall, the photos in the
manual were very helpful and only minor building experience is needed to follow them.
GWS EPS-400C(D) Geared
Speed 400 System
ICS-300 Electronic Speed
Control (ESC)
The ESC came with an
optional heatsink I received a GWS ICS-300J ESC with the review kit but suspect that it may not be the correct choice.
The manual says to use an ICS-400 ESC. My ICS-300 ESC was rated for 8amps continuous and up to
15amps peak short term so I figured it was worth a try on my Speed 400 motor. Additionally, the ESC
came with an optional heatsink that looked like a good idea to install. As it turned out, my ICS-300 ESC
worked just fine. The ICS-300J ESC is modified
for the supplied heatsink The heatsink is placed onto
the thermal pad
and then held in place with
the new shrink wrap. The steps to install the heatsink started by removing the existing shrink wrap on the ESC because a
new heatshrink piece is supplied to hold the heatsink in place and the plastic layer must not go in
between the power transistor and thermal pad. Make sure that the protective layers are removed from both sides of the thermal pad and then place it
directly onto the transistor. The heatsink can then be placed onto the pad and then held in place with
the new shrink wrap. Make sure that after you heat the shrink wrap that the heatsink is held firmly
against the thermal pad and the transistor. There should also be an opening for air flow at each end of
the heatsink. The control rod tubing is first
glued in place,
and then the wing nut glued
before assembling the
The fuselage is held together
with rubber bands while
drying Fuselage Assembly:
The first step in assembly is to glue the elevator and rudder tubing into the sides of the fuselage tail.
Although GWS supplies a tube of glue in the kit, I choose to use 5-minute epoxy just because it was a
bit faster to dry. The manual says to cut the tube to a length of 260mm but this was rather short and did not agree with
another photo farther along in the manual. I choose to cut my second tube at a length of 300mm. The above photo on the right shows the wing nut glued into place and you can see that my first 260mm
tube is a bit short. It can actually go as far as being in-line with the wing nut.
I then glued the fuselage together with Aileene's Tacky White Glue and held it with several rubber
bands until dry. The supplied GWS glue work work fine here as well. The fiberglass rod support is
glued into the bottom wing
After cutting hinge slots with
a razor knife,
the ailerons are glued into
the wing. Wing Assembly:
The first step in the wing assembly is to glue a fiberglass rod support into the top side of the bottom
wing. I used epoxy here but the GWS-supplied glue will also work fine.
After cutting out the ailerons from the wing, you need to cut some slots for the hinges and drill holes
for the torque rod. Now is a good time to paint the exposed white parts of foam back to Moth yellow. It
can also be done fairly easy after the model has been test flown as I did. The aileron gap was set to
match the torque rod
Support plastics are glued
into the wing and fuselage
The wing is secured on both
leading and trailing edges
I used the GWS glue to attach the ailerons to the wings. Instead of cutting grooves into the aileron for
the torque rod to sit in for a closer mate, I decided to leave the aileron out a bit to match the gap with
the center part of the wing and allow less binding on the plastic hinge material. Either way should work
fine. The next step is to glue some plastics into the wing and fuselage that will secure the wing on both
leading and trailing edges. The landing gear support is also installed at this time. The wing is locked in place
with a single screw
A perfect seam is provided
between the fuselage and
The bottom wing mounts with just a single screw in the trailing edge and is locked in the leading edge
with the double post. The wing to fuselage seam was a perfect fit on both top and bottom sides. It felt
solidly locked into place.
A metal joiner connects the
elevator halves together The elevator is then
connected to the horizonal
The supplied GWS glue
worked great on the hinges Tail Assembly:
The elevator halves are cut from the horizontal stabilizer and then attached together with a metal
joiner. Again, paint the exposed white foam, if desired.
Four hinges are used to hold the elevator to the stabilizer. I used epoxy for the metal joiner, and, after
it dried, attached the hinges using the GWS glue. The rudder is first cut and
then re-assembled onto the
stabilizer A steerable tailwheel is
attached to the rudder before
The finished tail sections are
then glued to the fuselage
The rudder is first cut and then re-assembled onto the vertical stabilizer in a similar manner. I added
the steerable tailwheel assembly onto the rudder before attaching it to the fuselage per the
instructions. I saw no issues with the stabilizer assembly and I am now ready to glue the tail together.
The tailwheel support bracket
is glued onto the fuselage
bottom. Be sure to check the
alignment of both stabilizers
to the fuselage
The tail assembly was quick
and easy The horizontal stabilizer is glued in place first and then the vertical stabilizer. The rudder and tailwheel
assembly is glued next and the final step is to glue the tailwheel support bracket onto the fuselage
bottom. A large compartment has
airflow from the front cowl
opening The GWS EPS-400C gear
motor simply pressed into
place Motor, Wing Strut, and Cowl Mounting:
Before installing the geared Speed 400 motor, I wired my ESC for a Dean's Ultra battery connector
instead of the stock red JST connector.
The motor simply pressed onto the pre-cut stick and was held securely with a screw through the plastic
into the wood. I then epoxied the stick into the fuse slot. Everything fit together very well.
Each strut is secured to the
foam in a pre-formed pocket
Strut and cowl supports are
first sanded and then glued in
Tiny screws then secure the
struts and cowl
I started gluing my strut supports in place on the wing and fuselage. It is always best to rough up the
plastic with sandpaper on the side to be glued. This provides a better hold. Missing cowl supports were
made from scrap plastic and
later found I simply cut 3 square pieces
and glued them into place on
the fuselage nose. The upper wing, cowl, and
gear mains were installed The manual seemed to miss a step before mounting the cowl and the kit did not contain the parts
needed. It went right into screwing the cowl in place on the fuselage. This was easily remedied by
making my own square cowl supports from the leftover plastic strut support material. I simply cut 3
square pieces and glued them into place on the fuselage nose. After my building was completed, I think I found the plastic pieces meant for the cowl mounting in a
separate plastic bag. There were these 4 white plastic pieces about the correct size in my leftover parts
After trimming the cowl and cutting out a hole for the prop shaft and another hole for airflow, I was
ready to mount it to the fuselage with three tiny screws. I could now see that there was a plan for proper airflow into the front of the cowl through large
openings in the fuselage to cool both the motor and ESC. This was a good design step by GWS for the
TM 400. At this point, I decided to deviate from the manual step sequencing because the next step was to
mount the lower wing which would block the inside compartment meant for installing the servos and
receiver. Since I didn't want to unscrew the wing again, I decided to leave this step for last. When I did
install the struts, you first glue the supports into both top and bottom wings. The struts are then
attached with the tiny screws supplied in the kit.
I installed the stock landing gear without issue. My Tiger Moth could now stand on all three wheels and
I was ready to install the three servos and linkage.
The components are placed in
positions shown in the
manual The linkages installed easily
with "Z" bends on only one
end Aileron control rods used "V"
bends for fine tuning
adjustment Servos and Linkage:
I put the components exactly where the manual showed them. I used Hitec HS-55 servos which fit
perfectly in the provided pockets. My GWS R4-P receiver has the full length antenna running through
the inside of the fuselage.
In the linkage photos above, everything installed easily and I only deviated slightly in some areas like
not using "Z" bends on both ends of the aileron rods. My GWS Tiger Moth 400 was
Ready-To-Fly at 14.1oz
without battery The plane balanced perfectly
without using any of the
supplied clay A 3-cell Kokam 1500mAh
Lithium pack provides a
perfect fit and balance I measured the 10.5amp
current draw to be within
motor specifications A closer look at the 3-cell Kokam 1500 pack in my TM 400 reveals that not only a great fit after some
slight carving under the dash, but the plane balanced perfectly with the stock GWS Speed 400 power
system without adding any of the supplied clay. Alternatively, the Thunder Power 3-cell, 1300mAh
Lithium pack is a bit lighter and will also work well with the GWS Speed 400 power system. Both Kokam
and Thunder Power packs are available at Hobby Lobby. The recommended 7-cell, 730mAh NiMH pack has only limited power for the TM400. You'll see a huge
power increase with a 3-cell Kokam 1500 pack. The Kokam 1500 cell can deliver up to 12amps
continuous and the 730mAh NiMH cell only about 8amps. Additionally, the 3-cell Lithium pack provides
the voltage of a 10-cell NiMH pack and therefore provides more power to the prop. I measured the
10.5amp current to be within motor specifications at full throttle for short periods using the 3-cell
Lithium pack and stock prop. I also felt that a 7-cell NiMH pack provided too low of a voltage for this power system but an 8-cell,
720mAh, NiMH folded pack would work fine with the GWS Speed 400 power system. An 8-cell folded
pack of 720mAh, NiMH cells also weighs about 4oz and can be purchased at Hobby Lobby.
The Tiger Moth 400 can take-off from grass, pavement, or simply hand-tossed into the air. Novice R/C
enthusiasts should solicit the help of an experienced pilot on the maiden voyage so it can be properly
balanced, trimmed out and flight tested. The steep angle climb-out after take-off reveals plenty of power in the Tiger Moth 400
We flew the Tiger Moth 400 twice today at lunchtime. Although the wind was changing directions and
speed from 5-15mph, the plane flew great! I had plenty of power to handle the wind when needed and
could throttle way down when it subsided. It flew inverted just as well with only a slight drop in lift from
the semi-symmetrical airfoil. Slow rolls and giant loops are easily performed
The roll rate was very scale and much slower than I have been used to with all my 3D plane flying
lately. When rolling with rudder correction, it looked very scale in the air. Check out the video for some
nice rolls! We took off from pavement and landed in grass several times without any sign of rollover. The
structural design of the plane is solid and I didn't notice any problems under these rather rough
conditions. GWS has elevated their original popular slowflyer design to an aerobatic parkflyer status! Flying low and slow across the field was made easy by the Tiger Moth 400
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