Electric Flash - 2004/03

March 2004 19
by Harry Stewart
I NORMALLY BUILD and fly fuelpowered
models. Through the years I’ve
constructed several 1⁄2A designs which I
have flown in local school yards and parks,
but as the local population has grown, the
noise associated with the aircrafts’ engines
has made these fuel-powered models
unwelcome. Electric power seemed the
obvious solution, but for a long time I
resisted, mainly because of the higher
weights and short run times I perceived to be
common with Electrics.
However, when I first drew the Electric
Flash I had been following articles reporting
on the newer battery technologies and
decided that maybe the time had come when
my objections could be conquered.
When I started I knew nothing about
electric flight except what I had seen in the
modeling magazines and my subscription to
John Worth’s Cloud 9 Micro RC Newsletter,
but I did know that I wasn’t interested in the
typical Speed 400 model or in the tiny stuff
about which John reported. I wanted
something in between—a slow flyer for
outdoor calm air that I could fly in relatively
small spaces in the mornings and evenings
without disturbing the neighbors.
My inspiration for the Electric Flash was
the old Comet Phantom Flash Rubber model.
I can remember one that my father built
when I was a child, and I used to watch in
amazement as it flew around in our living
room.
When I began to draw my plans, I
thought I had a pretty good idea of what
equipment I would be using and therefore
how much weight the model was going to
have to carry around. For radio equipment I
was going to use a Hitec single-stick, threechannel
AM radio. By removing the receiver
case, the receiver would weigh
approximately .5 ounce—as light as
anything commonly available at the time.
Two Hitec HS-50 servos would be
another .4 ounce and a Mini 5 speed control
from FMA Direct added another .2 ounce. I
replaced the Hitec switch with a .5-gram
switch from Cloud 9 Micro RC at
www.rcmicroflight.com/cloud9rc.
I wasn’t so sure about the motor/battery
combination. I wanted a running time
comparable to that of my fuel-powered
models, which is 10-15 minutes, and I didn’t
think I could get that from Ni-Cds at an
acceptable weight. My first thought was to
use rechargeable alkaline batteries I found in
a home-improvement store and a small
motor from a surplus outlet.
With this combination in mind, I set
March 2004 21
The Electric Flash can easily be outfitted with floats, and plans
for them are included.
The low-drag design of the floats allows for spirited off-thewater
performance. Check out the rooster tails!
You can convert the Electric Flash from floats to wheels and
then back again quickly with no trouble!
about designing the airframe. The completed Electric Flash was quite
attractive, but the available power was barely enough to keep it in the
air.
When my original motor/battery combination didn’t work out, I
looked into Lithium-metal batteries. However, since I was wanting to
keep this a low-cost project and I would not only have to buy the
batteries but the special charger and Electronic Speed Control (ESC)
that they require, I decided against them.
At that point I realized that I really didn’t know what I was doing,
so I began researching the Web sites of every electric-related supplier
I could find. I finally found what I thought would be an acceptable
combination when I downloaded Dick Miller’s “Motor
Characterizations” charts from the Internet.
According to the charts, a VL HY-50D motor on six cells would
give me the power I needed. Six of the then-new AAA NiMH cells
would give me the duration I was after at an overall weight of
approximately 8 ounces for the model, and I could charge them with
my existing Ni-Cd chargers.
I bought the motor and a couple of propellers from Cloud 9 and
had two 550 mAh AAA NiMH battery packs made at the nearest
Batteries Plus store. Then I had an attractive model that flew! I was
more than satisfied. It would do 15 minutes in a school yard, never
going higher than 50 feet. At a slightly larger site with some lift, 20-
25 minutes was the norm.
Unfortunately, somewhere I missed the part about never using more
than 6 volts with the HY-50D! Since I rarely used full power after
initial takeoff, it took me 10-12 hours to burn the brushes up in the
motor, but eventually I did. Even so, I would have gladly accepted that
lifespan and replaced the motor, but the HY-50D was out of production
and no longer available. (It is available again from Cloud 9.)
Type: Electric-powered RC park flyer
Wingspan: 28 inches
Power: GWS, MGK, or M100 motor
Flying weight: 8 ounces
Construction: Balsa and plywood
Covering/finish: Litespan attached with Sig Stix-It
Photos courtesy the author
22 MODEL AVIATION
If you are looking for an easy-to-build and fun-to-fly model as a
first or second construction effort, this may be it!
The rudder and elevators are actuated by pull-pull control via
Kevlar thread. Note the aluminum exit tubes for the thread.
The motor is mounted via a snap-tie. You can also see the Kevlar
thread attached to the servo output arm.
That’s the bad news; the good news is that now there are several
small electric motor/gearbox units in the 1-ounce category that are
suitable for the Electric Flash. More good news is that the AAA
NiMH cells have been upgraded to 700 mA capacity and are now
readily available and cost less than my originals. And the best news
of all is that with the new Lithium-Polymer batteries, flight times are
up even more and the weight is down compared to the NiMHs.
I am pleased with the Electric Flash. After a couple of false starts
I got exactly what I was looking for: a gentle, relaxing, slow-flying
park flyer that is able to handle a good breeze with excellent flight
duration, and the bonus is that it has also turned out to be a good
soarer and floatplane.
The first prototypes have been flying for more than three years,
and I have built several since then. So far they have flown with a
number of small motors—some more successfully than others.
I flew the first prototype for a long time with a GWS A motor
(aka the Lite Stick motor) from Balsa Products, at
www.balsapr.com, and an APC 8 x 6 slow flyer propeller from
Landing Products. This combination will weigh roughly 8 ounces,
total flying weight. A GWS C with the same propeller works well
too.
Then I upgraded to what I refer to as the “big block” motor: an
EMPS MGK motor/gear/propeller combination from Penn Valley
Hobby Center. This unit raises the total figure to approximately 8.75
ounces flying weight, but the model will have much more power.
And more recently I have used the M100 motor/gearbox from Jet Set
Models.
For relaxing slow/park flying, the GWS is the way to go. If you
just have to have more performance, the MGK or M100 will provide
it. Because the MGK will fly the Flash at low power settings, the
flight times can be almost the same as with the GWS.
EMPS cautions against prolonged use at full power with the
MGK on six cells. Believe me, you won’t need more than a few
seconds of full power at any time with the MGK. The M100 uses
slightly less current and has no such restriction.
The GWS units come with a capacitor across the motor
terminals, but I had to add two more from the terminals to the case
to eliminate glitches with my Hitec AM Focus 3. I used RadioShack
0.1mfd part 272-109As. On the MGK I used three 0.1mfd capacitors
supplied by EMPS. I used three on the M100 as well.
Since the Electric Flash was first designed, there has been an
enormous proliferation of micro Radio Control (RC) equipment
suitable for it: microreceivers, several 6- and 9-gram servos, more
choices of Electronic Speed Controls (ESCs), lightweight iron-on
coverings, micro hardware and wheels from Du-Bro at
www.dubro.com, and, best of all, the newer Lithium-Ion and
Lithium-Polymer batteries. (You need a special charger for Lithium
March 2004 23
Cut ribs using master rib template and sharp #11-blade knife.
One of the wing halves is shown under assembly. Shim up the
center ribs with scrap 1⁄32 sheet balsa.
Assemble the tail surfaces over the plans, and shim up the tips
and trailing edges with 1⁄32 sheet scrap.
The ribs, the trailing edges, the spars, and the leading edges are
shown ready for assembly.
The completed fuselage is shown. Note the hatch, the gear-plate
reinforcements, and the dowel wing hold-downs.
The fuselage parts are cut out and ready for assembly. There is
nothing difficult here.
Glue the formers to the right fuselage side. Make sure that they
are perpendicular to the fuselage side.
batteries, but there are many more choices and they are more
reasonably priced.)
Currently my favorite power combinations are the MGK with a
1200 mA Lithium-Polymer and the M100 with a 700-1000 Lithium-
Polymer, although the 700 NiMHs still work well with either.
CONSTRUCTION
If you have scratch-built, or plans-built, a couple of models, you
can probably build the Flash from the plans. In case you don’t have
that experience, I will try to explain how I built mine.
Wing: The hardest part about scratch building a tapered wing is
cutting the ribs. You can use the patterns on the plans, but I think it’s
easier to make a master rib from plywood or aluminum and use it to
cut all of the ribs by rotating it to the length of each rib as measured
on the plans. Cut the false ribs full length, and discard the part behind
the spar after you have made the spar cutout.
After you have cut all of the full-length ribs, stack them with all
leading edges (LEs) in line. Trim the LE radius back 3⁄16 inch. Mark
the spar location and make the cuts with a razor saw. Taper the cut
from 1⁄4-inch deep—or 3⁄8-inch deep if you are using larger spars (see
This is the completed airframe. Notice that the hinges have been
trial-fit; they will be removed for covering.
Assemble landing gear on a piece of scrap wood as shown.
24 MODEL AVIATION
There are minimal parts to this airplane, and they are all easy to build. Give the Electric Flash a try!
the following)—at R-1 to 1⁄8-inch deep at R-8.
Use a Master Airscrew Balsa Stripper from Windsor Propeller
Co., Inc. to trim the 1⁄32-inch center sheeting. If you can find straight
pieces of 1⁄4 square and 3⁄32 x 1⁄4 x 48-inch pieces for the LE and the
spar, you will only need one of each; otherwise, you will need two
pieces of 36-inch, 1⁄4 square, and 3⁄32 x 1⁄4-inch stock. (If you are going
to use the MGK motor, you might want to increase the spars to 3⁄32
inch or even 1⁄8 x 3⁄8 inch.) The trailing edge (TE) is 1⁄8 x 1⁄2-inch TE
stock.
Cut the LE, TE, and spar to the approximate length; leave a little
extra. Mark the rib locations on the LE and TE from the plans and cut
the 1⁄16-inch-deep slots for the ribs. Only slot the TE for R-2, R-4, R-
6, and R-8. I used a hacksaw blade with a couple of scraps of balsa
glued to it with cyanoacrylate as a depth gauge. I finished the slots
with a jeweler’s file. Pin the two spars together at one end, and taper
the spar from 1⁄4 inch to 1⁄8 inch with progressive passes with a Master
Airscrew razor plane.
Pin the LEs over the plans. Use scraps of 1⁄32 sheet to shim up the
R-1 and R-2 ribs. Use the R-2 and R-8 ribs to locate the spar and pin
it down. Pin down the TE. Add the rest of the ribs except for the R-
1s, which you add after the wing halves are joined. Trim the ribs for
overall length as required. Make the wingtips by gluing two oversize
pieces of 3⁄32 sheet together with the proper grain orientation, and
then cut the tip to shape and glue it in place.
After you have the wing halves framed up, sand the dihedral
angle into the ends of the LEs and TEs and the spar so that you have
the required 3 inches of dihedral at each wingtip, and join them with
the 3⁄32 x 1⁄4-inch (or whatever you used for spar material) spar joiner.
Butt-glue the LEs and TEs by flooding the joints with cyanoacrylate.
Add the two R-1 ribs side by side at the center so that they are
vertical when each wingtip is blocked up 3 inches.
Sheet the center-section, top and bottom, with 1⁄32 x 1-inch-wide
cross-grain sheet strips. The sheeting will overhang the R-2 ribs a
little, but that’s okay.
March 2004 25
Full-Size Plans Available—see page 191
26 MODEL AVIATION
March 2004 27
All that is left is to shape the LE and
lightly sand the structure, and you are ready
to cover.
Tail Surfaces: The tail surfaces are
straightforward, made mostly from 1⁄8-inch
square and 1⁄16-inch sheet TEs. Make the TEs
from three oversize pieces of 1⁄16-inch sheet
with the proper grain orientation, and then
cut them to shape. The tips of the vertical
stabilizer and the elevators are a single piece
of 1⁄16-inch sheet. For the vertical and
horizontal stabilizers, pin the LE and TE
pieces to the plans, cut the ribs to length, and
glue it in place with cyanoacrylate.
The center-section of the horizontal
stabilizer is made from 1⁄8-inch sheet that will
provide a good surface for attaching it to the
fuselage. There is also a 1⁄8-inch square
doubler in the center of the TE to strengthen
it.
The vertical stabilizer will have a 1⁄8-inch
square tab attached to the bottom that fits
into the slot in the horizontal stabilizer. The
vertical stabilizer’s TE extends down to the
bottom of the fuselage where it attaches for
added support. Remember to shim up the tips
with 1⁄32-inch scrap to center them before
gluing.
The vertical stabilizer bottom rib is
made from 1⁄8 x 1⁄4-inch stock. Use two
pieces of 1⁄8-inch square glued together if
you have to. Don’t forget the 1⁄8-inch square
tab attached to the bottom of the vertical
stabilizer that fits into the slot formed in the
center of the horizontal stabilizer.
The rudder is made like the vertical
stabilizer. Shim up the TE with scraps of 1⁄32-
inch sheet. Add the 1⁄8 x 1⁄4-inch doubler in
the lower bay that supports the control horn.
After removing the rudder from the plans,
add the 1⁄32-inch sheet fairings to both sides
of the bottom to bring it up to a full 1⁄8-inch
width.
Build the elevator halves in one piece
with a full-length LE that goes from tip to
tip. Add the 1⁄8-inch square doublers at the
inboard edges of the TE for control-horn
support. Shim up the TE with scraps of 1⁄32-
inch sheet, and then cut and glue the ribs.
After removing from the plans, add the
1⁄32-inch sheet fairings at the inboard ends of
the elevators. Using a razor plane or a
sanding block, taper the 1⁄8-inch square ribs
of the elevators and rudder to match the 1⁄16-
inch TE.
Install the 3/64-inch-diameter music-wire
elevator joiner and glue it in place with
cyanoacrylate, and then remove the center
piece of the 1⁄8-inch square elevator LE.
Shape the LEs and TEs to a rounded shape,
taper them at the tips to match the 1⁄16-inch
sheet outlines, and smooth out all of the
pieces.
Before you are ready to cover, you need
to fit the hinges. I used 3⁄32-inch-wide strips
of Sig’s Easy Hinge material. Use three
hinges on the rudder and two on each side of
the elevator. Cut the slots and trial-fit the
hinges before covering to make sure that
everything lines up properly. Now you are
ready to cover.
After covering, you can glue hinges in
place with cyanoacrylate. Because the model
flies slowly, it takes more than the usual
amount of control-surface movement. Before
permanently attaching the control-surface
hinges, make sure that you have at least 30°
of movement to either side of neutral on the
elevator and the rudder.
Fuselage: Cut the fuselage sides, formers,
and cabin parts from 1⁄16-inch sheet. You
could make one-piece fuselage sides, but by
doing the fuselage sides and cabin sides in
two pieces there is less wasted balsa. The
formers and the front and back of the cabin
are cut cross-grain.
The plans show a constant-width fuselage
from F-2 forward. My first prototype had a
pinched nose where F-1 was narrower than
F-2. It all depends on what motor you will
use. For motors with narrow gearboxes, you
can reduce the size of the front if you like
that look; for motors with large spur gears,
the wider front works better.
After you have cut out all of the pieces,
glue the cabin sides to the fuselage sides.
Mark the former locations and, using a
square or a builder’s triangle to ensure
accuracy, glue the F-2 and F-5 formers to
one side. If you are building the wide-nose
version, you can also glue F-1 in place now;
otherwise, leave it for later.
Now is a good time to discuss servo
Visit the MODEL AVIATION Digital Archives!
Featuring a searchable database of Model
Aviation issues and articles from 1975 to 2000.
This is by far one of the best
efforts AMA has made to
construct something that is for
every member.
—Marco Pinto
Peninsula Channel Commanders
San Francisco CA
Find it at www.modelaircraft.org. On the main page, click
on the “Members Only” section, log in with your last name
and AMA number, then click on the “Visit the Digital
Archive” image.
mounting. It is easier to install the servo
mounts, F-3, F-4, and F-6 now, but if you
want to wait to see how the model will
balance, you can install them later. The servo
mounts shown are for Hitec HS-50 or Cirrus
CS-10 servos from Hobby People. If you
will be using something different, you will
have to modify these pieces to suit.
F-4 is for the rudder servo, and F-6
provides a secure mounting for the single
servo mounting screw used. F-3 supports F-
4/F-5 and keeps the fuselage sides from
bowing when the elevator servo is installed.
There is a projection on top of the HS-50
and the CS-10. I mount the elevator servo
through a matching hole in the left side of
the fuselage and keep it in place with a block
of balsa between the servo bottom and the
fuselage side. A piece of tape keeps the
block in place. Carefully matching the hole
in the fuselage to the projection on the
elevator servo keeps the servo from rotating,
and the block wedges it in place and keeps it
there. No mounting screws are necessary.
After you have glued the formers to one
side of the fuselage, carefully add the other
side. Make sure you attach this side even
with the first, or you will introduce a twist
into the fuselage.
The first three inches of the bottom
sheeting aft of F-2 is 1⁄16-inch thick, crossgrain,
of course. Attach this piece now to
keep the fuselage square. You can sand
this piece to blend into the rest of the 1⁄32-
inch bottom sheeting later.
If you are using a narrowed F-1, install it
now. Glue the gear plate in place along with
its 1⁄8-inch square braces. If you narrowed the
nose, trial-fit the gear plate and trim off the
portion where the fuselage narrows. Finish
sheeting the bottom front of the fuselage
with another 3-inch piece of 1⁄16-inch sheet.
Using 1⁄32-inch material, sheet the bottom
back to F-5.
Install the front and rear cabin pieces: C-
1 and C-3/C-4. Sand the bottom of C-1 so
that the hatch will butt up to it. Make sure
that the “V” in C-3/C-4 matches the dihedral
angle of the wing because the wing sits on
top of C-3/C-4 so that it can slide back easily
if it gets “bumped.”
Pull the fuselage sides together at the rear
and glue them together, making sure that
they join on the centerline. To get the
straight-side taper from F-5 back to the tail I
used a couple pieces of 1⁄2-inch square from
F-5 to the tail and a couple rubber bands to
squeeze the sides straight while I added the
top and bottom 1⁄32-inch sheet to the rear of
the fuselage. Not only do I like the straightsided
look, but it saves a little weight in top
and bottom sheeting compared to a curved
side.
Before you sheet all the way to the tail on
the bottom, make the 1⁄32-inch-music-wire
tail skid and the 3⁄8 x 1⁄2-inch balsa mounting
block, and glue them in place. The top
sheeting on the rear of the fuselage only goes
back to the stabilizer LE. The hinge line of
the horizontal stabilizer is 1⁄4 inch ahead of
the rear of the fuselage sides; trial-fit it now,
and match the top sheeting to it exactly.
Make the hatch from 1⁄16-inch sheet and
the hatch braces from 3⁄32-inch square. Make
sure that the hatch braces extend back under
C-1. Install the 1⁄16 plywood latch plate at F-
1. Make the latch from 1⁄32 plywood. Trial-fit
these hatch pieces so that the hatch can be
installed and removed easily.
All that is left is to drill the wing-holddown
dowel holes and install the dowels.
Lightly sand the whole affair—remember to
blend the 1⁄16-inch bottom sheeting into the
1⁄32-inch bottom sheeting—and it is ready for
finishing.
Landing Gear/Wheels: Bend the three
pieces of the gear from 3/64-inch music wire.
Temporarily fasten the front and rear gear
legs 11⁄4 inches apart to a scrap block of
wood. Bring the ends together, and bend
approximately 3⁄8 inch of the rear gear leg so
that it is parallel to the front gear leg. Bind
the axle/spreader to the gear legs with soft
copper wire, and solder them together.
After the fuselage is painted, you can
bind the gear assembly to the gear plate with
thread or soft copper wire. I made my wheels
with 1⁄4 balsa centers and pipe-insulation
foam tires with 1⁄16-inch-aluminum-tube
wheel bearings. The wheels only weighed
roughly a gram each.
March 2004 31
The only tricky part is making the 1⁄4-
balsa wheel round. I drew the circles with a
compass and cut them as close to round as
possible but slightly oversize. I drilled a
hole through the centers using the compass
center mark as a guide and bolted them
together with a piece of 2-56 threaded rod,
washers, and nuts. I chucked this in the drill
press and used a sanding block at high rpm
to sand them round.
When I was satisfied, I removed the 2-56
rod and installed a 5⁄16-inch-long piece of
1⁄16-inch-diameter aluminum tube in each
wheel for a bearing. After a couple coats of
paint, the wheels are ready for the pipeinsulation
tires, which I glued to the balsa
with cyanoacrylate.
For wheel collars I used a plastic tube,
that came with a spray can, that just slipped
onto the 3/64-inch-diameter axle. A couple
1⁄8-inch pieces glued to the axle with
cyanoacrylate have held the wheels in place
nicely. If you don’t want to build your own
wheels, you can buy a set of light wheels by
Du-Bro at your local hobby shop.
Covering and Finishing: I covered both
of the early prototypes with Litespan
attached with Sig Stix-It. Today there are
many more choices of lightweight
covering materials available.
Since no fuel is involved, some of the
park flyers I’ve seen have their balsa parts
left natural to save weight. I prefer a more
finished look, so I painted the fuselage
(and the wheels, as I already noted) with
Sig dope. A couple coats of sanding
sealer, a light sanding, and then a couple
coats of color did the trick.
After you cover the tail surfaces—but
before you permanently glue the hinges in
place with cyanoacrylate—make sure that
the control surfaces have plenty of free
movement. You will need at least 30° in
each direction. Also, it is probably easier
to drill the holes in the elevator and rudder
for the control horns, at the locations
indicated on the plans, before they are
attached to the fuselage.
Now all you have to do is attach the tail
surfaces to the fuselage and you are ready
to install the motor and radio equipment.
Equipment Installation and Control
Linkages: The motor unit you choose will
determine the method of mounting
required. I usually mount motors to a tray
that fits between the cheek cowls. A drop
of cyanoacrylate at the front and back of
each side holds the tray in place. Don’t use
too much adhesive in case you have to
adjust the thrustline.
For the GWS motors I attach a piece of
3⁄16 balsa to each flat side of the gearbox
with silicone adhesive, fit the unit between
the cheek cowls, and attach it with a
couple drops of cyanoacrylate on each
side. On both of my models I mounted the
motors with a slight amount of downthrust
and right thrust—just enough of each so
that I can see that the motor is not exactly
zero-zero. Both prototypes have flown fine
with no further adjustments.
The holes in F-1 and F-2 allow for the
wiring to run from the motor to the speed
control. The battery is located under the
hatch between F-1 and F-2. The speed
control is behind the battery, just in front of
F-2. I used a Deans two-pin connector to
join the battery and the speed control. I put
the micro switch in the positive lead to the
speed control. The receiver connection from
the speed control goes back through F-2 to
the throttle position on the receiver. The
receiver, less its case, sits just behind F-2.
Since there is no vibration and I can’t
imagine the Flash hitting anything very
hard, I didn’t use any padding. The servos
are mounted as explained in the fuselage
section and plugged into the receiver.
For control linkage I employed a pullpull
system using Kevlar thread for the
cables. Control horns are 1⁄16-inch-diameter
aluminum tubes cut to the same length as
the spread of the servo output arm. These
are glued with cyanoacrylate into the control
surfaces as close to the hinge line as
possible at the locations shown on the plans.
The rudder cables exit the back of the
cabin and run back over the top of the
fuselage. The elevator cables run back along
the left side of the fuselage. The Kevlar
thread is looped under the servo-arm screw,
under the servo arms, up through the servoarm
holes, and back to the control horns.
The threads run back to the control horns
and are pulled through from each side,
pulled tight, and wedged in place with a
piece of 1⁄16 square balsa stick. A couple
drops of cyanoacrylate keeps everything in
place.
If you need to adjust the centering,
loosen the servo-arm screw and slide the
thread one way or the other. When you have
what you want, retighten the servo-arm
screw. Charge the batteries, and I think you
are ready to fly.
Flying: If you’ve checked the center of
gravity (CG), there are no apparent warps,
the propeller turns the right way, up is up,
down is down, right is right, left is left,
and the battery is charged, you are ready to
fly. If you have a smooth surface, the
Flash will rise-off-ground. Over grass I
usually hand launch. With full power and a
gentle push, away it goes.
With the Hitec transmitter and the
FMA speed control, there seems to be
roughly seven “clicks,” or ratchet
positions, of the throttle lever between off
and full power. When you get to full
power, more clicks on the throttle lever do
you no good.
That’s okay, because once the Flash is
flying I usually reduce power to roughly
50% unless I want it to climb. Even then it
will climb nicely at less than full power.
The whole idea, after all, is for the model
to fly as slow as possible and to maximize
the flight time.
The Flash is not aerobatic; it will loop,
but that is about all. I just like watching it,
with the same fascination I remember from
32 MODEL AVIATION
childhood, as it floats around almost
silently with only the slight whir from the
gears noticeable from the ground.
The Flash will handle quite a breeze
with the larger motors, but it is happiest
with the smaller motors in calm air. If you
find some rising air, this model will get
way up there and climb at low power
settings. When you are ready to land,
reduce power until it descends.
Set up the approach, control the
model’s descent with the power until you
can get it to where you want it to land, cut
the power completely, glide down, and
hold it off until it almost stops before it
settles in. If you’ve done it right, the
rollout will be approximately a foot on
grass, roughly six feet on a ball diamond,
and maybe two or three times that on
pavement.
The FMA Direct Mini 5 speed control
does not have a low-voltage cutoff for the
motor, but I’ve never found this to be a
problem. When the Flash won’t climb any
more at full power, it is time to land—but
after 15-20 minutes of relaxing, fascinating
flight, you won’t mind at all. MA
Harry Stewart
220 Nihell St.
Nevada City CA 95959
Sources:
FMA Direct
5716A Industry Ln.
Frederick MD 21704
www.fmadirect.com
Hitec RCD, Inc.
12115 Paine St.
Poway CA 92064
www.hitecrcd.com
Hobby People
18480 Bandilier Cir.
Fountain Valley CA 92728
www.hobbypeople.net
Jet Set Models
117 2nd St.
Lakewood NJ 08701
www.jetsetairplanes.com
Landing Products
1222 Harter Ave.
Woodland CA 95776
www.apcprop.com
Penn Valley Hobby Center
837 W. Main St.
Lansdale PA 19446
www.pennvalleyhobbycenter.com
Sig Manufacturing Company, Inc.
401-7 S. Front St.
Montezuma IA 50171
www.sigmfg.com
Windsor Propeller Co., Inc.
Box 250
Rancho Cordova CA 95742
www.masterairscrew.com
Visit the AMA Education Committee
Web site at www.buildandfly.com.