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If you are looking for a little
bit different type of control line model, then Short Snorter might fit the bill. It
was designed by George Hinz and appeared in the October 1958 issue of American
Modeler magazine. Short Snorter is .20 to .35-size stunt or combat model that is
essentially a flying wing, and features a built-up fuselage and wing. The wingspan is
around 40", but of course since you will be printing the plans, you can make the
model larger or smaller. standard construction materials and methods are used
throughout. Mr. Hinz cautions about making certain that the center of gravity is
properly located since a tail heavy flying wing is extremely unstable.
Short Snorter
 By George Hinz.
Here's a really good looking and fine flying
"no-body" (well, almost) stunter by George Hinz ... Hobby Helpers has the full size plans
so let's go!
Although the flying wing is becoming as popular as conventional craft in the stunt
circle, one seldom sees a model of this type that presents a proto-type appearance. Most
are the "flying plank" type used in combat events.
In order to break away from this trend and knowing that the flying wing stunter can
perform as well as any model of standard design we came up with "Short Snorter."
The short tail moment arm (which makes for quick control response) is combined with
a fairly long nose moment to achieve a smooth and positive flight path at all altitudes.
Due to light weight and low drag (a characteristic of most flying wings) this job will
really scoot with a hot "19" or "25" up front. Install a "29" or "35" and you will have
a "guided missile." For the inexperienced flyer we recommend the smaller displacements.
The plane will practically fly itself in level flight, requiring only very slight
control movements even under gusty wind conditions.
One very important point that cannot be overemphasized on a model of this type is
the longitudinal center of gravity position. If you value your model, don't fly it in
a tail heavy condition; oh, it will be a spectacular sight while it is still in the air
... which won't be long. Better to make the model slightly nose heavy. Stick to the C.G.
position shown on the plans and you'll have no trouble on this score.
O.K., let's get to work. We start with the wing panel since this is the central unit
around which the model is built.
Wing Panel. Cut 15 main ribs from 3/32" medium hard sheet balsa and
4 center section ribs from 1/8" hard. The inboard panel is 2" longer than the outboard,
accounting for the unequal number of main ribs. Cut lead-out holes on each inboard wing
rib.
Each center section rib is slightly different in regards to the bellcrank mount slots;
R-1 has none, R-2 thru -4 have slots progressively longer. Combined with the stepped
bellcrank mount, it is almost impossible to pull the bell crank loose in flight.
 Make bellcrank mount and stub spar from 1/8"
plywood. Lightly cement R-2 and R-3 to stub spar and bellcrank mount, add R-1 and R-4.
Select 1/4" square hard balsa 36" long for the lower spar; using 1/16" sheet scrap balsa
spacers under the spar, pin it in position over plan. Set previously assembled center
section unit on spar, use scrap balsa blocks to hold it horizontal. Put main ribs in
place on spar, keeping these horizontal by scrap balsa blocks under the ribs. Add 1/4"
square x 36" hard balsa top spar. With all ribs lined up, add 1/4" square x 36" hard balsa
leading edge and 1/16" x 1" x 36" hard balsa trailing edge top cap strip. The upper tip
rib gussets may be installed now or later when L.E. (leading edge) and center section are planked.
Apply cement to all accessible joints; let assembly dry for at least 8 hours.
We proceed with elevators, tail horn and push rod. The elevators are built as
follows: Pin 1/4" square medium hard balsa L.E. to plan, then cut trailing edges from 1/8"
medium hard
balsa noting inboard T.E. (trailing edge) is 2" longer than outboard one. Place 1/16" sheet balsa spacers
under these and pin down over plan. Cut a strip of 1/4" x 32" medium hard balsa into correct
lengths for ribs and cement these in place. Add the 1/4" medium hard sheet balsa end ribs,
with grain fore and aft. Let assemblies dry thoroughly before removing from plan. Sand
now to airfoil shape indicated. Tail horn and push rod are fabricated using directions
on drawings.
When cement has dried, remove basic wing structure from plan and cement all joints
that were not accessible before. Taper hard balsa 36" x 1/4" x 3/8" to 1/8" at rear edge,
cement in place under top T.E. cap strip; add 1/16" x 1" x 36" bottom cap strip. After
sanding down any high spots on wing ribs, bottom of wing is planked with 1/16" med. soft
sheet balsa. Use one sheet 3" wide and 36" long for L.E. planking and shorter pieces
for center section. Cut out section, including that portion of L.E. that lies forward
of stub spar and between ribs R-2 and R-3. Also cut hole as indicated on wing for push
rod, another about 1/2" in diameter directly under bellcrank pivot point. Modify a commercial
bellcrank or make one from dural to dimensions given; assemble it and previously formed
push rod. Bolt this assembly in place on bellcrank mount. Install lead-out wires.
Top of wing is planked and tip rib gussets added. Rough carve two wing tips from soft
balsa. Drill holes for lead-out wires in left tip block; tack glue these in place. Assemble
the two elevators to tail horn using cloth reinforcement around joints for extra strength.
This assembly is joined to wing with cloth hinges, then 1/4" sheet balsa fairings between
tips and elevators added. Sand wing tips and fairing pieces to shape. Carefully remove
tips from wing, hollow left one to lighten it. Hollow space in right tip for approximately
2 oz. ballast. Tips cement back in place.
To finish wing structure, insert lead-out wire grommets in left tip. Lightly sand
entire wing. Apply 3 to 4 coats of dear dope, sanding between coats with progressively
finer sandpaper - this prevents wood grain from raising when wet covering material is
applied. Wing and elevators can be covered now or left until the entire ship is assembled.
In any case, it would be a good idea to cover both sides of the center section with silk
or nylon before regular covering is put on - this will beef-up the wing considerably.
Fuselage and Vertical Fin. Start the fuselage by cutting out 2 sides
from 1/8" hd. sheet balsa to heavy outline shown on side view. Cut 2 side doublers from
1/8" plywood. Join sides and doublers with liberal amount of cement, hold together with clamps
or other means until dry. Make formers next using 1/8" ply for F-1, F-2 and F-3 and 1/8"
sheet balsa for F-3A thru F-6. Cut vertical fin parts from 1/8" medium hard sheet balsa,
assemble directly on plan. Sub fin is 1/8" sheet balsa on each side of 1/16" ply. Insert
3/32" music wire tail wheel fork before assembling.
You might be tempted to omit the tail wheel and fork and use the sub fin as a tail
skid. To do so would allow the model to assume an excessive angle of attack on the ground.
This would make the ship balloon on take offs and landings, especially into the wind.
 Continuing with construction ... shape tail block
as per side and top views and section C-C. Cut two maple or other suitable hard wood
motor mounts. Cut exhaust opening in one of the two side-doubler units to suit the engine
you intend to use. Fuel tank is made of tin-plate or shim brass, or a commercial unit
is adapted. The tank, an integral part of the fuselage assembly, cannot be removed after
installation without great trouble, so double check now all solder joints for leakage.
Cement motor mounts to doublers; use "Perfect" blind nuts and 4-40 bolts (section
A-A) for added strength. This type of installation has survived straight-down crashes
with only broken prop and cracked cowl blocks resulting.
Drill holes in F-2 and F-3 for spade bolts or other landing gear securing method you
use. Slip F-1 into slot, butt fuel tank solidly against F-1 and bottom of motor mount.
Install F-2 and F-3, then cement opposite side. Check that mounts are parallel both top
and side. Finish sides by cementing tail block in place; when dry, add formers F-4, F-5,
F-6. Now fuselage is cemented to wing. Temporarily cut away those portions of the sides
that fit over the upper trailing edge of the wing. Pin the wing into place on the fuselage;
check alignment before cementing. Then cut away side pieces are glued back. Form landing
gear from 3/32" music wire, fasten to fuselage at formers F-2 and F-3; 1/8" sheet balsa
fills space between L.G. struts if desired. Wrap with double layer of silk or nylon for
strength. Cement vertical fin in place; offset it to inside of circle about 1/8" at leading
edge. Sub-fin is added. Fuselage bottom is planked with 1/8" sheet balsa with grain crosswise.
Plank upper portion of fuselage from F-4A to F-6 with 1/4" x 1/8" balsa; add all fillets
and sand smoothly into structure.
Fully Enclosed Engine Cowling. Since most builders have their own
favorite method for making cowls the following is for the inexperienced in this phase
of modeling.
Select spinner of proper size, install on engine. Plug engine intake and ex-haust
openings to keep out balsa dust. Drill mounts to give 2 to 3 degrees engine offset toward
outside of circle. Set "Perfect" blind nuts in place on top of mounts, bolt engine temporarily
in position. Blind nuts permit easy removal of motor for servicing. Select 4 soft balsa
blocks for top, bottom and side pieces. Hollow these just enough to accommodate crank
case, glow-plug, tank vents, etc.; tack cement in place. When the glue has set, carve
to outlines on plan. Sand cowling to streamlined shape, fairing it smoothly into spinner.
A hole for the needle valve is drilled and dowels wrapped with fine sandpaper finish
it to proper diameter. Remove blocks and hollow as per dotted lines - modifying to suit
engine used. Clean all balsa dust from the engine but leave the intake and exhaust port
plugs in place. Inside of cowl blocks get at least four coats of fuel-proof clear dope.
Bolt engine back in position, securely cement top and side blocks in position. Lightly
tack glue bottom block in place. Fill all nicks and pits, then blend vertical fin, sub
fin and wing root fillets into fuselage with "Plastic Balsa" or talcum-dope mixture.
When this dries thoroughly, fuselage and fin assemblies are fine-sandpapered smooth.
Apply 3 coats of clear dope, sanding between coats with progressively finer sandpaper.
Covering. Wing and elevators are now covered if not previously. Use
Silkspan, silk or nylon. Apply covering wet for best results. Grain of material runs
span-wise. Remove all wrinkles from covering before clear-doping to frame work. For neat
job apply dope only around edges. When dry, brush on 6 coats of butyrate clear dope,
adding 3 drops of castor oil to each ounce to "plasticize" the dope. This prevents covering
from becoming so tight it could warp frame work.
If you used silk or nylon for covering, the first 2 coats of clear dope should be
thick to prevent the dope from "bleeding" thru and forming droplets inside. Fuselage
gets 6 coats of sanding sealer. Lightly sand between every second coat on both wing and
fuselage using #400 wet-or-dry paper. Let last two coats dry for six hours before sanding,
then brush on two coats of butyrate silver dope. This will show up defects such as wood
grain or small nicks not noticeable before. These are filled in and sanded down before
the final finish.
Color Scheme and Final Finish. Dope interior of cockpit and top of
cowling black, then carve and install pilot and head rest if desired - paint head rest
tan or brown to make it look like leather. Trim a commercial bubble canopy to proper
size, cement neatly on fuselage . Mask off areas on canopy that will be doped to simulate
metal framing. Use your own color scheme on the rest of the model. Original except for
top of cowl: entire model was given four coats of pearl grey butyrate dope. Spinner and
front of cowl red; top-rear of cowl and forward canopy framing black. Wing numerals black;
fuselage numerals powder blue. British insignia on wing and fin and all numerals were
home-made from decal paper obtainable in most art supply stores. Give decals a coat of
hot fuel proofer before the model is flown.
Final step before model can be flown is to remove engine, take out intake and exhaust
plugs, clean it and engine compartment of all dust accumulated during sanding and finishing.
Dope engine compartment to match exterior paint job, install engine and hook up fuel
line. Slip needle valve into place and tack glue lower cowl block back into position.
There, she's done - let's try her out!
Flying. Select a reasonably calm day for the first flight. Hook up
.012" to .016" thick control lines around 60' long and check controls for binding or
stiffness. Check that wheels roll freely and run true. Select and install a propeller
of matching pitch and diameter for your engine. Fire up engine and set mixture so it
will be slightly rich in level flight . Take off directly down wind. Let model roll along
ground until flying speed is reached, then give slight up-elevator and your ship will
be airborne in a smooth and realistic manner. Get used to the model in easy stages, When
you are sure everything is functioning properly, try some of the basic maneuvers. After
that, let your ability as a flyer be your guide.
Short Snorter Bill of Materials
Three sheets of 1/8" x 3" x 36" med. hd. balsa for fuselage sides. formers. planking,
vertical fins, elevator T.E.'s and center section ribs; 3 sheets of 1/16" x 3" x 36"
medium hard. balsa for wing planking: 1 sheet of 1/16" x 2" medium hard balsa for trailing
edge cap strips: 1 sheet of 1/8" plywood, 12" x 6" for formers F-1, F-2 and F-3, side
doublers, bellcrank mount and sub spar; 1/16" plywood 3" x 8-1/2" for sub fin core; motor
mount stock, 1/2" x 3/8" x 10"; 4 pieces 1/4" square x 36",1 hard balsa for wing spars
and leading edge and elevator leading edges; 1 piece 1/4" x 3/8" x 36" for wing trailing
edge; 2 soft balsa blocks, 9" x 2"x 2" for wing tips, also four soft balsa blocks of
assorted sizes for engine cowling: scrap 1/4" medium hard sheet required for wing T.E.
fairings, wing root fillets and elevator end ribs; 2 packages "Perfect" blind nuts; 2
packages 4-40 motor mounting bolts; 2" diameter spinner: bubble canopy; 2 sheets white
Silkspan, silk or nylon; clear dope, sanding sealer, silver dope and colored dopes of
desired color. (All dopes to be hot-fuel proof); decal paper for insignia and numerals.
Short Snorter Plans Sheet #1
Short Snorter Plans Sheet #2
Posted January 13, 2018
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