Airplanes and Rocket website visitor
Michael M. requested that I scan and post this article from the May 1970 American Aircraft
Modeler. The Escondido Mosquito is a tiny rubber-powered free flight model with a wingspan
of just under 8". Per designer Bill Hannan, "The silly little thing is great for the
living room or office."
This silly little thing is great for living room or office. You can build it in one hour.
model, if correctly constructed, can be made to perform in the average-size living room
or office. It makes a fine conversation piece that will capture the attention of even
non-aviation-minded visitors. The design is intended to be rugged enough to withstand
the rigors of bouncing off walls and furniture that inevitably occurs when flying in
restricted spaces. While the duration cannot be expected to compare with "serious" indoor
models, it is quite possible to achieve several laps of the room, and contests between
two or more of these tiny terrors are great fun!
Models of this general type have been popular for many years, and in fact, some of
the earliest published plans were for flyers of this breed. Of the variety of interesting
names which have been bestowed upon them, such as "Parlor Pursuits," "Midgets," etc.,
the name that seems to have turned up most frequently is "mosquito" or variations thereof.
For example, an advertisement appeared in the Dec., 1910 issue of Aeronautics magazine,
which offered for sale a tiny machine called the "Jersey Skeeter." During the late 20's,
a small model named the "Baby Mosquito Flyer" was marketed by a firm called the "Mosquito
There is no easier way to make a balsa prop; just be sure the hole is centered and
Our little "Escondido Mosquito" carries on this long established tradition of balsa
wood insects. "Escondido" is a Spanish word meaning "hidden," however, it is also the
name of the small city in California where the author resides.
Although the model is constructed in a straightforward manner, it is important to work
carefully and to bear in mind that the lighter your mosquito, the greater its duration.
Since the plans are full size, you will be able to work directly over them, using a piece
of waxed paper or clear plastic food wrap to protect the drawings from glue.
Wing: Select a light and straight piece of 1/16" sq. strip balsa.
Usually, a search through a number of 1/16" sq. strips will reveal a few which are slightly
undersize, and that size would be a good choice for this job. Additionally, the strip
can be lightly sanded on all four sides to reduce the weight and remove the little hair-like
fibers that may be present. The trick is to sand in one direction only, to avoid buckling
the strip. Pin down the parts to the plan using straight pins. Do not pierce the wood,
but rather angle the straight pins on both sides of each strip to hold it in place. Only
a small amount of glue is needed at each joint.
When the wing structure has dried, cut the leading and trailing edges in the exact
center, in order to allow one tip to be raised for dihedral purposes. This tip should
be raised 1 3/4" above the building surface, and supported with a suitable block. Cover
the wings on the top side only, using the lightest grade of tissue paper that you can
obtain. Condenser paper is a good choice, since it is very thin and non-porous, but superfine
Japanese tissue can be used instead. Do not shrink or dope the covering, since this might
Wing mounts: Cut the wing mounts to shape from fairly hard 1/32"
sheet balsa. Note that the two mounts are different, to provide for an angle of incidence.
These mounts also help to strengthen the wing dihedral joint.
Fuselage: Select a light but stiff section of 3/32 x 1/16" balsa
for the fuselage. It is important that the material be rigid enough to resist "bowing"
under the strain of a fully wound motor. Sand lightly, and notch for the 1/16" -sq. tail
boom. Note that the tail boom is offset, as shown on the plan top view, to enable the
model to fly in small circles. Glue this joint sparingly, since the angle may need to
be slightly altered to suit your particular flying space limitations.
Metal parts: The propeller shaft and rubber motor rear hook are bent
to shape using needle-nose pliers. Music wire of approximately .015 diameter will work
well. The prop shaft bearing is made from aluminum or dural sheet stock, which is drilled
to accept the prop shaft, then bent as indicated on the drawing. Roughen the portion
of the aluminum where it contacts the fuselage, and glue in place. A few turns of sewing
thread will greatly strengthen the joint. Glue and bind the rear wire hook in similar
Tailplanes: Glue the 1/16 x 1/32 x 3 1/4" balsa stabilizer leading
edge onto a sheet of tissue paper. Allow a few moments for the adhesive to set, then
trim the tissue to the triangular shape shown on the plan. This is easier than trying
to glue the stick onto an already cut triangle of tissue. The rudder is constructed in
the same way.
Glue the stab onto the lower side of the tail boom, using the plan top view as an
alignment aid. Next, glue the rudder to the side of the tail boom.
Propeller: The prop hub is made from a medium-weight
piece of 1/8" - sq. balsa strip. After cutting to length, mark the exact center of the
hub, and carefully push a thin straight pin through it. Do this slowly, and try to keep
the pin properly centered as viewed from the end and side of the hub, so that the finished
prop will not wobble. Next, measure and mark off the portions of the hub which will be
cut away to receive the prop blades. A diagonal line should be drawn on each end of the
hub to serve as a guide for the depth and direction of each cut. It is safer to cut the
wood away a little at a time, rather than trying to re-move the entire corner at once.
The blades themselves are cut from 1/32" sheet balsa. Using a paper pattern as a template,
make the two blades as nearly alike as possible, then carefully sand and slightly round
the edges. When gluing the blades onto the hub, be sure to check that they are properly
centered. After the glue has dried, place a thin wire through the prop-shaft hole, and
check the propeller balance. One blade will probably swing to the bottom, indicating
the need to be lightened. A little sanding should take care of the problem, and while
absolute perfection is not required, the better the balance, the smoother will be the
Slide the prop shaft through the fuselage shaft bearing, and add a glass "seed bead"
for a thrust bearing. After inserting the shaft into the prop hub, bend the end of the
shaft into a "U," using needle-nose pliers, and force the "U" into the front of the prop
hub. Apply a film of glue over the area to keep the shaft in a secure position. A tiny
drop of oil applied to the shaft will help reduce friction.
The wing may now be installed. The mounts should be a fairly snug fit on the fuselage,
which will hold the wing in place, and yet permit wing shifts for balance purposes.
Power: This model requires only a very tiny amount of power, and
in fact, too much power should be avoided. The exact power required will depend upon
the weight of the finished model, but here are some suggestions for a start. If 1/24"
- sq. rubber is available in your area hobby dealer's shop, give that a try. A single
strand of it may prove adequate. Simply tie a loop in each end of the strand, or if you
prefer, the loop at each end may be secured with a couple of turns of sewing thread.
Be sure to trim the loose ends of the rubber so that they will not rub against the fuselage,
which wastes power.
Or, try a single strand cut from a common office-type rubber band. These vary widely
in size and quality, so some experimenting will be needed. Another possibility is to
slice your own thin rubber strand from a wider piece, using a sharp razor blade and a
If your model turns out to be very light, you may wish to investigate the use of elastic
shirring thread. This is the type of elastic used in the tops of socks, shorts, and similar
wearing apparel. Again, size and quality varies from brand to brand, so do a little looking
around. In the case of the tiny sizes of this substance, a single loop (two strands)
may be needed to provide the right power.
Flying: After you have installed the rubber motor, try a gentle hand
glide. Shift the wing slightly forward or rearward as required to achieve a gentle descent.
Next, try a few turns of the prop, and launch again. If all goes well, try a few more
winds and repeat. We prefer to fly our mosquitoes in quite small right-hand circles.
In order to achieve this (assuming no warps), it may be necessary to add a small amount
of ballast to the right wing tip. Although modeling clay is the accepted ballast material,
it has a disadvantage, in that dropped pieces may become imbedded in the rug and cause
stains. Needless to say, this does not go over too well with the lady of the house. As
an alternative, try an artist's kneaded eraser, or typewriter cleaning dough. This material
can be handled about like clay, but it will not stain rugs, etc., since it is non-greasy.
Remember to launch the model gently, with the propeller turning. It may also help
to release the model in a slight right bank to give it a hint of what it is expected
to do. If your flying area is fairly large, you may be able to fly in large diameter
circles without needing wing tip ballast. On the other hand, if your flying site is unusually
small, it may be necessary to offset the rudder still farther, and add additional wing-tip
ballast. All of this can be determined during testing. If the model should happen to
crash, the damage can be easily and quickly repaired. Remember, however, that the added
weight of the glue required for repairs may bring about the need for re-trimming of the
With a little practice, you should find it quite easy to launch the model, watch it
make several laps of the room, and have it return to your hand. This may be the answer
for the fellows who like free flight, but don't want to chase models!
1 strip of 1/16" sq. balsa: wing parts, tail boom
1 small piece of 1/32" sheet balsa: tail leading edges, wing mounts, prop blades
1 small piece of 1/8" sq. balsa strip: prop hub
1 small piece of 1/16" sheet:
fuselage; OR, 1 strip of balsa 1/8 x 1/16", cut down to 3/32 x 1/16"
1 small sheet
of lightweight tissue or condenser paper: covering
1 piece of music wire approximately
.015 dia.: prop shaft, rubber hook
1 glass "seed bead": thrust bearing
thread: binding purposes
1 small scrap thin aluminum sheet: prop-shaft bearing
Rubber strand for power (see text)
Modeling clay or artist's kneadable eraser:
TOOLS AND OTHER REQUIREMENTS
Single-edge razor blade or modeler's
Plans - Wingspan = 7-15/16"
for larger version>
The AMA Plans Service offers a
full-size version of many of the plans show here at a very reasonable cost. They
will scale the plans any size for you. It is always best to buy printed plans because
my scanner versions often have distortions that can cause parts to fit poorly. Purchasing
plans also help to support the operation of the
Academy of Model Aeronautics - the #1
advocate for model aviation throughout the world. If the AMA no longer has this
plan on file, I will be glad to send you my higher resolution version.
Try my Scale Calculator for
Model Airplane Plans.
Posted June 8, 2012