Improvements in Flying Machines with Beating Wings.
Year: 1897

page_text: Date of Application, 30th Oct., 1897-Accepted, 26th Feb., 1898
COMPLETE SPECIFICATION.
Improvements in Flying Machines with Beating Wings.
I, ALEXANDER ADAMS, of "Finsbury," Yule Street, Dulwich Hill, Sydney, New
South Wales, Civil Engineer, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
As every attempt of man to raise and carry himself on the air by his own muscu-
lar exertions as in ornithological flight has proved a complete failure the object
of this invention is to provide a light, inexpensive and convenient means by which
he may accomplish this feat on beating wings and for kindred purposes.
The first part of this invention relates to the use of air compressed by a small
hand-pump into a light steel tube reservoir. The pressure of the air so confined
is caused to act in an inverted single-acting cylinder or other receptacle, (the con-
fined air passing to and fro between the cylinder and reservoir in each stroke and
having no exhaust or other communication with the outer air,) so as to resist,
sustain and balance the resultant forces developed on the under surfaces of the
wings in flight together with the weight of the operator.
Fig. 1 illustrates the principle in which the arrows indicate the direction of the
forces, A being the point of reaction, B B the points of suspension, C air under
pressure in the cylinder D, F F the wings, L cords or links limiting the ampli-
tude or extent of depression of the wings in relation to the centre of gravity; the
vane and the cross-heads T may be any convenient distance above and below the
level of wings necessary to ensure stable equilibrium. By this arrangement
support is obtained from the atmosphere parachute-fashion, the wings being poised
and free to play up-and-down at the will of the operator-a part which any
ordinary person may perform comfortably.
There are therefore two distinct forces or agencies required in this the natural
form of flight, viz.-a continuous reacting force and an elevating and propelling
one. This invention is intended to supply the former.
23
In using the machine as illustrated the operator seats himself firmly on the
saddle S (Fig. 4) so as to bring the collar or tube C against the shoulders in the
hollow at B and placing his hands on the handles E E and his feet on the treads
DD (Fig. 3) he is in a position to apply the full force of his extensor muscles
and to strike the down stroke, (aided by the compressed air,) with a force
approaching a horse-power. The pressure of the enclosed air may be so regulated
as to permit of the wings assuming the elevated position shown in Fig. 3 with
the operator on the saddle so that in the up-and-down action of his body in the
stroke the pressure in the cylinder will, in addition to balancing the wing forces
raise or lift up a portion of his weight according to the rate of wing motion
required, a portion being required in the return stroke which is effected by the
mere flexing of the legs and the consequent transfer of his weight to the saddle.
During action communication between the cylinder and reservoir is continuous
the weight of the apparatus acting in concert with the resistance of the air on the

page_text: wings driving the compressed air back into the receiver in the up stroke and
vice-versa.
·
The value of the reacting power required may be found by dividing the wing
into transverse sections say 12 inches wide and allowing 6 to 7 of a square foot
area of sustaining surface to each pound.
Regard the wing as a lever with fulcrum at B (Fig. 1) and find the reaction
which each section produces at A (Fig. 1) add and multiply by 2. It should
be noted that the supporting power per unit of surface increases with the area and
is proportional to 10 where S is the surface, The approximate propelling
power required may be similarly found. Adopting thirty double strokes of 15 to
18 inches each minute as the rate of wing motion in getting under weigh the
vertical velocity motion of any section is proportional to its distance from B
(Fig. 1) and its resistance sq'r. foot is found from the formula (), V being
the velocity in feet per second.
To twice the sum of the reactions thus found add from 30 to 40 % for concavity
of wings together with one-third or thereabouts of the weight of the operator or
operators. The up stroke is largely immaterial the difficulty has been to prevent
the ascent of the wings.
The invention is also applicable to flying-machines designed for other purposes
than man-flight. If so desired the mechanisms may be so arranged that the cylin-
der and reservoir shall be "fixed" in relation to the wing motion; the upper end
of the cylinder being open and the compressed air acting on the under surface of a
movable piston the said piston communicating its motion by any suitable means
to the wings. This arrangement together with the motive power required in
large machines may be built on a carrier rigidly suspended at any convenient dis-
tance beneath the wings necessary to ensure stable equilibrium and the continued
maintenance of a small incidence angle in the wings whether a single pair or in
duplicate.
As the compressed air practically supports all the stress arising from the weight
of the machine and its load the power required for flight is thus reduced to a frac-
tion of that hitherto considered necessary and hence lightness in the construction
of the apparatus although desirable is not essential to flight.
Nickel steel or mild weldless steel tubing with steel tension wires are recom-
mended as the best materials for construction.
<<
As the pressure of a gas is proportional to its density the volume of the com-
pressed air reservoir should be such as to fairly maintain the pressure throughout
the stroke. This can best be obtained by reference to a graphic description of
Boyles Law"
on the compressibility of gases in which P V is a constant, P being
the pressure and V the volume. The main tubes of wings and other parts may,
if so desired be utilised for the purpose of storing air under pressure and connected
with the receiver proper by a flexible tube at M (Fig. 4).
The second part of my invention consists in convenient arrangements of
mechanism for increasing or reducing the incidence or forward angle of the wings
with the horizon as required in ascent or descent and of simultaneously adjusting
the suspended limb vertically or nearly so under the line of centre of pressure
in the wings as F F (Fig. 2) for ordinary flying angles; the rollers on the ellip-
tical swinging arcs settling automatically in or about that position also.
The mechanisms are so designed that all these motions may be in action simul-
taneously with the wings, and which with a slight modification are applicable to
duplicate cylinders and wings, the connection between the supporting limb i.e.
the wings and the suspended limb involving the principle of the universal joint.
The machine may be so designed as to have its centre of gravity, when in mid-
air, located well beneath the points of suspension for the purposes of stability,
the small extra sub-resistance incurred thereby may be reduced to a minimum
by a canvas "starling" or any other reducing device in front and counteracted
by a small overhead adjustable vane at any required elevation as V (Fig. 3) and
operated by the cord Y (Fig. 4). Increased lateral stability and steadiness of

page_text: motion may be obtained by a vane fixed parallel with the direction of motion as
at L (Fig. 4). Where two machines are built in tandem the tubes of this vane may
be made to answer as a means of connection overhead.
The start is the crucial test and should be effected against the wind or in its
absence acquire initial momentum on sloping ground. The stop should also be
made against the wind.
In order that the invention may be better understood and as showing how it
may be applied I append six sheets of drawings as follows:-
Fig. 1 Illustration in outline.
Fig. 2: A plan in which A A is a balancing arm carrying racks each side and
wing hinges front and rear, B B points of suspension from each wing, C C collar
or upper part of air chamber, D D rollers running on elliptical arcs, E safety valve,
F F approximate line of centre of pressure in the wings showing its coincidence
in the same vertical plane with the centre of the suspended limb, G and H anterior
and posterior margins of wings respectively, K K elliptical arcs swinging on
hinges at B B the ratio of the diameters of which will depend on the width, shape
and curvature of wings and the consequent movement of the centre of pressure
line with which the rollers should coincide, P is a pressure gauge, T T light pliable
steel wire cords passing over wheels and limiting the amplitude of wings. The
arrow indicates the forward direction.
Fig. 3.
Front elevation to a one-twelfth scale, A is a safety valve, _B_B_the
points of suspension, C C compressed air chamber, D D treads, E E the handles,
K the incidence angle cord, I I suspension rods or tubes, L vane, S saddle, TT
amplitude cords and V counteracting vane at any convenient elevation above
wings.
Fig. 4 Side elevation, A A wing connections, B rack, pinion and guides, C C
compressed air reservoir, F stop-cock between reservoir and cylinder D, G vertical
left-handed screw carrying nut H, L parallel vane, O crossheads, P air pump,
R gauge Y operating cord for vane V and Z a milled-head screw for regulating
the quantity of air pumped. The dotted lines show the position when the inci-
dence angle is increased.
;
Figs. 5 Vertical and horizontal_sections of the cylinder and its connections,
B guide rod for nut H, D cylinder, E non-moving piston of leather washers satur-
ated in oil and tallow, F stop-cock, L milled-head screw opening and closing an
escape slot and thus controlling the quantity of air pumped, R inlet valve, V check
valve and T T cross heads and treads.
Figs. 6 and 7: Vertical section and plan of the mechanism for controlling the
angle of flight, A is a cord wheel which if turned in the direction of the arrow
increases the forward angle and vice-versa, F à safety-valve designed to give a
varying pressure by turning the milled-head screw as required, G left-handed
screw having the bevel wheel C fast on its end as shown, P pressure gauge. The
small wheels D D gear with wheel C and operate the pinion P on the rack R
(Fig. 8).
Figs. 9: Front views of Fig. 8 in
the worm-wheel and worm, G G guides
the rack on its upper and under faces.
in section at R.
elevation and part section, C and D being
which are also partly seen at E grasping
The rack is fast on the tube and is seen
Figs. 10 are the intermediate bevel wheels the relative sizes of which govern
the velocity ratio of the pinion on the rack R (Fig. 8) with that of the nut H
(Figs. 4 and 5) and will vary as the movement of the centre of pressure for each
particular width shape and curvature of wings.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed it is to be understood that
I do not confine myself to any particular shape, size or materials for my invention
and I declare that what I claim and desire to secure by Letters Patent are:-
First. The use of compressed air as a reciprocating force for the purpose of

page_text: assisting in the up-and-down beating motions of the wings of machines designed
for artificial flight in conjunction with pedal action or other suitable motive
power.
Second. The mechanisms as described for operating the incidence or forward
angles of the wings with the horizon in flight and of simultaneously adjusting the
suspended limb vertically under the line joining the centre of pressure of the
wings for ordinary flying angles.
Third. The use of an overhead counteracting vane at right angles to the line
of forward motion.
Dad 1007
ALEX. ADAMS, C.E.,
Inventor.