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Globe Swift building instructions
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Much of this text was written in 1947 and has been
cribbed from Gary Hunter's website...
www.theplanpage.com/esp/swift.htm
The plan is originally by Earl Stahl and is very similar the Keil
kraft version, but is slightly more detailed. I have made a few
"adjustments" to the original plans and provided cutting
templates for many parts. The plans are more than fifty years old and
thus have not been metricated.
(Thanks are due to
David Livesay for pointing me in the right direction.
If any copies of the original Keil Kraft plan, or building
instructions, still exist I would be extremely pleased to receive a copy.
The Globe-Swift is a snappy looking, fast little sportster.
Looking for all the world like a miniature fighter, the Swift gains
many admirers because of its appearance. But that is not where the
aeroplane's appeal ends, for it is an easy-to-fly craft with
exceptional performance. With pilot and passenger and an 85 hp engine,
it cruises at 125 mph for 600 miles; a 125 hp engine can be installed
and it's speed is even greater. The undercarriage retracts in flight,
but when it is lowers and the flaps are depressed, the Swift slows up
so that it eases on to the runway at close to 45 mph. Staunchly built
of metal, it is unusually safe and durable. All in all it is a
sportsman pilot's dream.
We have attempted to capture the eye appeal and flight
characteristics of the actual aircraft in our model; how well we have
succeeded can only be judged by building and flying one yourself.
Building the model is not difficult as standard construction
practices are followed throughout; before starting, though, study the
text and drawings to fix the details in your mind. Work carefully as
the reward for this is a better appearing, finer flying model.
CONSTRUCTION
- 1
- The manner of fuselage construction calls for the use of
four keels cut to shape from 1/16" sheet balsa. To obtain their
shape trace the top, bottom and side outline shapes of the body.
- 2
- Bulkheads, also 1/16" sheet, are cut in accordance
with the patterns given; two of each being required. Pin the top and
bottom keels to the view and cement half of the bulkheads to place.
Attach a side keel and when dry remove the structure from the plan and
add the remaining bulkheads and keel.
- 3
- Stringers are 1/16" sq. stock; attach the ones
nearest the side keels first placing them on opposite sides in pairs
to keep from pulling the structure out of line.
- 4
- Between formers C and F where the wing fits in, curved
pieces are cut from 3/32" sheet and they are shaped so as to make
the fuselage sides fit to the curvature of the wing's upper surface.
- 5
- Other items to be attached to the frame are the 1/32"
balsa cockpit outlines as well as the very hard 1/16" balsa
blocks in the rear, which anchor the motor.
- 6
- The nose block just forward of bulkhead A is made from
pieces of 1/8" sheet cemented cross grain. Cut out the center for
the removable portion to fit into and cement the whole nose in so it
can be roughly cut to shape and then finished with sandpaper.
- 6
- A hard balsa or soft white pine propeller block is
needed for the flying model. Drill the tiny hole for the prop shaft
first, then cut the blank to size and shape shown. Cut away the back
surface of the block until the under camber is as desired, then thin
the front until the blades are of the desired thickness. Round the
tips and reduce the depth of the hub a bit as shown. Blades are
brought into balance by sanding. A free-wheeling gadget that will
permit the big blades to spin freely in the glide is recommended for
better flights. On our original model we used a second propeller, a
scale one. It was made to the shape shown and we used a number of
laminations of contrasting color wood to make it look realistic.
- 7
- Tail surface construction is elementary and both
tail plane, and fin are made in a similar manner. Cut the outline
shapes from 1/16" sheet balsa and spars and ribs are 1/16"
sq. stock. When the flat frames are dry, lift them from the plans over
which they have been assembled and cement very soft 1/16" sq. strips
to top surface of tailplane ribs. The underside of the tailplane ribs
has 1/32" soft balsa strips. These are later, pared and sanded to
the streamline rib shape shown. The fin ribs have 1/16" strips
both sides. Be sure to notice that the tail plane has dihedral; it is
cracked in the middle and tips are raised to provide this.
- 8
- Wings are easily assembled in two halves. Ribs are cut
from 1/32" sheet except No. 3 which is 1/16" thick; sand
them carefully to exact size and cut the notches for the spars. The
spars and leading edge are cut from sheet balsa and the trailing edge
is a strip of 1/8" x 3/8" balsa tapered in correct
proportion. Use pins to hold the various parts and place over the
plans, and when they are finished fit the two halves together with
1-3/8" dihedral at each tip.
- 9
- A sketch shows the landing gear detail. The strut is
.040" diameter piano wire bent as shown to attach to the wing
structure. Sew the strut to the wing with cotton and cement the area
liberally. Scale effects of the gear are represented by slipping
rubber sleeving, obtained from electronic suppliers, over the strut.
- 10
- Wheels may be purchased, but they are made so easily
from laminated balsa disks that it is hardly necessary. Cement fine
bore brass tubing into the wheels to act as a bearing so that the
wheels will turn freely.
- 11
- Covering is probably the most important item for a neat
looking model but the balsa frame must be carefully built and sanded
to prepare for this. Use coloured tissue for lightness and work
carefully using tissue adhesive to make the tissue stick. Use a
separate piece of tissue for each side of each wing half and tail
surface section. For the fuselage numerous small pieces of tissue
neatly overlapped are required to avoid unsightly wrinkles. Water
spray the covering lightly to tighten it, but do not apply any dope
until the whole aircraft has been assembled.
- 12
- Assembly of the components should follow this procedure:
Slip the wing into place and cement it. Align the tail plane with the
wing and attach it, too. Now finish underside of the wing-to-fuselage
opening as well as the tail plane root top with strips of 1/16"
balsa and tissue. Fix the fin perpendicular to the tail plane,
offsetting the leading edge about 1/32" for a right turn in the
glide. One or two coats of light dope may be applied to the covering
to tighten it further and toughen it.
- 13
- Now for the more minor finishing details. The cockpit
enclosure is made from thin celluloid or melinex may be used for this
purpose. Make paper patterns for each section of the windshield
before cutting them from the sheet. When cementing the sections, be
careful to avoid cement smears. The structural details are represented
by doping thin strips of dark tissue to the transparent surface.
Incidentally, it should be noted for exact scale builders that the
aft section and middle top portion of the cockpit enclosure are
coloured Plexiglas on the real plane to lessen the effects of the hot
sun. Finish the undercarriage and tail wheel assembly by painting,
etc. License numbers, radiator grill, wing walks and the like are
effectively simulated by coloured tissue skillfully used. Exhausts and
other minor details are fashioned from scraps and help much to
improve the appearance without increasing the weight appreciably.
- 14
- Installation of the rubber motor makes the little
Swift ready for a test hop. Since each model will vary in weight and
efficiency, the proper amount of power must be determined for each;
in all probability four strands of 1/8" flat brown rubber will be
right for an average model, but six strands may be required for a
heavier one. Lubricate the rubber before placing it within the
fuselage. The strands are hooked to the prop shaft and the other ends
are dropped through the fuselage where they are held in the rear by
the tiny bamboo pin.
- 15
- Flight performance depends mainly how carefully the
model has been built. On the other hand, though, no model regardless
of perfection of construction will give maximum performance without
proper adjustment. With this in mind strive to get the most from your
Swift in the way of flying satisfaction. First, roughly adjust the
center of gravity by adding a small amount of weight within the nose
or tail as may be needed to bring the ship into balance when held
under the wing spar. Then make any further adjustments by gliding
from shoulder height. If it stalls, add weight to the nose; if it
dives, remove some of the weight or place a bit in the extreme tail.
- 16
- First power flights should be made with just a few
turns, and as performance improves and confidence is gained increase
the power. Tilting the thrust line down will eliminate a tendency to
stall while under power, while right or left thrust will control the
power circles. As flights become satisfactory use a mechanical winder
and stretch the strands of rubber out the nose before starting to
build up maximum power. Most low wing scale models fly best when
they are adjusted for a large left hand circle while under power and
then once the motor is exhausted the turn should veer to a sweeping
right one; this is typical of the Swift.
The original text was scanned from January, 1947 Model Airplane News,
but has been reworded in places to suit modern British methods and language.
Written... May 2001,
Revised... 29 May 2001,
New Domain... 25 October 2003,
Upgraded... 17 May 2007,
Source Code last updated...
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