A tandem-rotor autogiro has a control system that facilitates operation of the tandem-rotor autogiro by fixed-wing aircraft pilots, without the requirement of extensive additional flight training. The autogiro includes forward and rearward non-powered rotors mounted in tandem on the fuselage of the aircraft. The forward rotor is controlled by manipulation of a control stick, and the rearward rotor is controlled by manipulation of foot operated pedals and trim control sticks. In a preferred embodiment the forward rotor is mounted in a plane vertically above a plane of the rearward rotor so as to facilitate an efficient aerodynamic air flow through the rotors.

1. Field of the Invention 
The present invention relates to a tandem-rotor aircraft, and more 
particularly to a tandem-rotor autogiro having controls that are similar 
to that of a standard fixed-wing aircraft so as to facilitate operation of 
the tandem-rotor autogiro by fixed-wing aircraft pilots without the 
requirement of extensive additional flight training. 
2. Background of the Invention 
In the field of avionics there are numerous types of aircraft such as 
fixed-wing aircraft, helicopters and gyroplanes. The most popular type of 
aircraft is the fixed-wing aircraft due to its fast flying speed and large 
carrying capacity. Most pilots are initially trained, therefore, to fly 
fixed-wing aircraft. FIxed-wing aircraft, however, are subject to numerous 
constraints, such as fast take off and landing speeds, which necessitate 
long runways. A fixed-wing aircraft typically includes two or more 
stationary airfoils and a power unit that functions to propel the aircraft 
in a forward direction. Accordingly, air that is forced rearwardly about 
the airfoils acts to provide lift and maneuverability to the aircraft. 
The lift and maneuverability of a standard fixed-wing aircraft typically 
are controlled by airfoil control surfaces such as ailerons, an elevator, 
a rudder, and trim tabs, or combinations thereof. The airfoil controls for 
the standard fixed-wing aircraft generally include a control stick, rudder 
pedals and trim tab control knobs. The control stick generally operates 
the ailerons and elevator. Specifically, port or starboard movement of the 
control stick causes attendant movement of the ailerons to roll the 
aircraft in a corresponding port or starboard manner. Forward or rearward 
movement of the control stick causes attendant movement of the elevators 
to pitch the nose of the aircraft in a corresponding downward or upward 
manner. The rudder is controlled by a pair of foot-controlled rudder 
pedals. Specifically, forward movement of the port rudder pedal causes 
port movement of the rudder to produce a port yaw of the airplane. Forward 
movement of the starboard rudder pedal causes starboard movement of the 
rudder to produce a starboard yaw of the airplane. Manipulation of the 
elevator trim tab knob and the aileron trim tab knob causes attendant 
movement, respectively, of the elevator trim tabs and the aileron trim 
tabs. Movement of the trim tabs further refines adjustment of the control 
surfaces so that the aircraft will maintain altitude and course without 
continuous pressure on the main controls. 
Rotary-wing aircraft, such as helicopters, are popular because they are 
highly maneuverable and are capable of vertical lift takeoffs. 
Helicopters, however, have relatively slow flying speeds, and the flight 
characteristics of a helicopter are very different from that of a standard 
fixed-wing aircraft. Accordingly, control of a helicopter requires 
additional flight training for fixed-wing aircraft pilots who wish to fly 
a helicopter. 
A helicopter typically includes one or more powered rotors to provide lift 
to the helicopter. The angle of attack of each of the individual blades of 
a rotor, or the angle of attack of the entire rotor, may be changed during 
flight to provide the appropriate lift and maneuverability. Specifically, 
a collective pitch-control stick generally is used to operate the pitch of 
all of the individual blades of the rotor, to provide vertical 
maneuvering, whereas a cyclic control stick is used to operate the pitch 
of individual blades of the rotor as each of the blades moves through the 
plane of rotation of the rotor, to provide horizontal maneuvering. Heading 
control pedals are used to control the pitch of the blades of the rear 
rotor, if present, so as to control the heading of the helicopter. 
Gyroplanes, also called autogyros, are popular in that gyroplanes require a 
relatively short distance for landings due to their low landing speed, 
allow independent control of fore and aft rotor angles of attack, in 
multiple rotor craft, and generally are cheaper to manufacture than 
helicopters. Gyroplanes are also aerodynamically stable. Gyroplanes have 
roll and pitch stability due to the pendulum effect, and yaw stability 
generally due to the presence of a vertical stabilizer and rudder. 
Gyroplanes are aerodynamically similar to fixed-wing aircraft in that 
gyroplanes include one or more non-powered airfoils, such as rotors, and a 
power unit that functions to propel the gyroplane in a forward direction. 
Accordingly, like the fixed-wing aircraft, the lift and maneuverability of 
the gyroplane is determined by the action of the forward, or downward, 
speed of the gyroplane, which causes air to pass rearwardly and upwardly 
around the rotors. The pitch of the rotor may be controlled by tilting the 
entire rotor hub. In some instances, a cyclic control may be used with the 
rotor. A collective control is generally not present. Accordingly, control 
of a gyroplane requires additional flight training for fixed-wing aircraft 
or helicopter pilots that wish to fly a gyroplane. 
SUMMARY OF THE INVENTION 
The present invention provides a gyroplane aircraft having a tandem-rotor 
system, and controls that are similar to that of a standard fixed-wing 
aircraft so as to facilitate operation of the tandem-rotor autogiro by 
fixed-wing aircraft pilots without the requirement of extensive additional 
flight training. The autogiro of the present invention includes forward 
and rearward non-powered rotors mounted in tandem on the fuselage of the 
aircraft. In a preferred embodiment the forward rotor is mounted in a 
plane vertically above a plane of the rearward rotor so as to facilitate 
an efficient aerodynamic airflow through the rotor system. The fuselage of 
the gyroplane preferably is manufactured of a size to carry substantial 
loads, such that the gyroplane may be used in place of long-haul trucks, 
particularly in areas having poor road conditions. 
Each of the non-powered rotors is capable of independent tilting movement 
with respect to the fuselage in response to movement by the pilot of the 
aircraft's flight controls. Similar to a fixed-wing aircraft, the flight 
controls of the present invention preferably includes a control stick, or 
a yoke, foot pedals and a trim control stick. Forward manipulation of the 
control stick causes attendant forward tilting movement of the forward 
rotor with respect to the fuselage, which decreases the lift of the rotor 
thereby causing the nose of the gyroplane to descend. Rearward 
manipulation of the control stick causes attendant rearward tilting 
movement of the forward rotor with respect to the fuselage, which 
increases the lift of the rotor thereby causing the nose of the gyroplane 
to ascend. Similarly, tilting of the control stick to one side of the 
fuselage causes attendant tilting of the forward rotor to that side which 
tends to yaw the gyroplane in the direction of the rotor tilt. Forward 
manipulation of the starboard foot pedal causes attendant tilting movement 
of the rearward rotor toward the port region of the fuselage so as to 
facilitate a starboard turn of the aircraft. Forward manipulation of the 
port foot pedal causes attendant tilting movement of the rearward rotor 
toward the starboard region of the fuselage so as to facilitate a port 
turn of the aircraft. Manipulation of the trim control stick causes 
attendant forward or rearward tilting movement of the rearward rotor with 
respect to the aircraft fuselage. Tilting movement of the rear rotor is 
used to compensate for variations in the longitudinal location of the 
center of gravity of the gyroplane so as to trim the aircraft during 
flight. In other embodiments, the flight controls may include additional 
trim control sticks, a control wheel, or a "wireless" control system, such 
as a computerized control console. The controls of the tandem-rotor 
aircraft of the present invention, from the pilot's perspective, function 
in much the same way as do the control of a standard fixed-wing aircraft 
such that a pilot trained to fly a fixed-wing aircraft would easily adapt 
to operation of the gyroplane of the present invention. 
Accordingly, an object of the present invention is to provide a 
tandem-rotor aircraft that is simple to operate. 
Another object of the present invention is to provide a tandem-rotor 
aircraft that is operable by pilots of standard fixed-wing aircraft 
without the requirement of extensive additional flight training. 
Yet another object of the present invention is to provide a tandem-rotor 
aircraft wherein each of the tandem-rotors may be independently tilted 
relative to the body of the aircraft. 
Still another object of the present invention is to provide a tandem-rotor 
aircraft wherein the forward rotor is positioned in a plane vertically 
above a plane of the rearward rotor. 
Another object of the invention is to provide a control mechanism which 
makes use of the broad center-of-gravity limits of the tandem rotor system 
of the invention. 
A further object of the invention is to provide a control mechanism which 
makes use of the high level of static and dynamic stability of the tandem 
rotor system of the invention. 
The subject matter of the present invention is particularly pointed out and 
distinctly claimed in the concluding portion of this specification. 
However, both the organization and method of operation, together with 
further advantages and objects thereof, may best be understood by 
reference to the following description taken in connection with 
accompanying drawings wherein like reference characters refer to like 
elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Known gyroplanes have been limited to an oddity or toy because of their 
slow speed and very narrow center-of-gravity limits. Gyroplanes, however, 
have an important advantage over other aircraft forms in that they can 
take off and land at very low airspeeds, eliminating the need for long 
runways which fixed-wing aircraft require, and may still be designed to 
economically carry a significant payload, unlike helicopters. The use of 
two rotors, in tandem, on a gyroplane broadens the center-of-gravity 
limits, enabling the carrying of large, heavy loads and taking off and 
landing in confined areas, and doing so more economically than a 
conventional rotary wing aircraft. 
Traditional aircraft controls include a stick, or yoke, to control pitch 
and roll. This is true for fixed wing aircraft, helicopters and single 
rotor gyroplanes. Likewise, rudder pedal control yaw in all three aircraft 
types. All three aircraft types have some form of trim control to relieve 
control pressures during steady state flight. The aircraft and control 
system of the invention extends conventional appearing control mechanisms 
to a tandem-rotor gyroplane, and describes how each control input achieves 
a desired result by affecting the attitude of the two rotors. 
Referring initially to FIG. 1, aircraft 10 of the invention typically 
includes a gyroplane including a fuselage, or body, 12 having a forward 
region 14, also called the nose or fore region, a rearward region 16, also 
called the tail or aft region, and a longitudinal axis 18 extending 
therethrough. Nose region 14 includes a windshield 20 that encloses a 
cockpit area 22 containing a pilot's seat 23 and a control input device 
24. The control input device, also referred to as the flight controls, 
preferably includes a control stick 26 and trim control sticks 28 and 29, 
each of which are mounted on a console 30 of the fuselage cockpit, and a 
pair of foot pedals 32 mounted on a floor 34 of the cockpit. In another 
embodiment the control stick may include a yoke, a control wheel or any 
control input device known in the art of fixed-wing flying aircraft and 
the trim control sticks may include trim control knobs or the like. The 
fuselage further includes a cargo area 33 positioned rearwardly of cockpit 
22 and landing wheels 35 extending from the fore and aft regions of the 
fuselage. As will be understood by those skilled in the art, the fuselage 
may be manufactured in any known exterior shape so as to provide the 
desired aerodynamic and functional cargo requirements of the gyroplane. In 
a preferred embodiment, the fuselage of the gyroplane is manufactured of a 
size to carry substantial loads such that the gyroplane may be used 
instead of long-haul trucks, particularly in areas having poor road 
conditions. 
Aircraft 10 further includes a pair of rotors 36 including a forward rotor 
38 and a rearward rotor 40 mounted in tandem on an upper surface 42 of the 
fuselage. The rotors each include a plurality of individual rotor blades 
44 and 46, respectively, mounted to respective rotor shafts 48 and 50 by 
respective rotor hubs 52 and 54. Rotor shafts 48 and 50 typically are 
journaled to the fuselage such that their vertical axes 56 and 57, 
respectively, are positioned substantially vertically when the gyroplane 
is at rest on level ground. Each of the rotors is capable of independent 
tilting movement of the rotor hubs about their respective rotor shafts 
toward the fuselage. The combination of the rotor hub and rotors is also 
referred to herein as a rotor unit, or as an auto-rotating airfoil. In a 
level or neutral orientation, wherein the rotors are each positioned 
perpendicular to vertical axes 56 and 57, respectively, forward rotor 38 
defines a plane of rotation 58 that is positioned vertically above a plane 
of rotation 60 of rearward rotor 40. This vertically staggered orientation 
of the rotors provides a relatively undisturbed airflow to the rearward 
rotor that facilitates the aerodynamic efficiency of the aircraft. 
Still referring to FIG. 1, aircraft 10 further includes a power system 
including a power unit 70, such as a gasoline powered engine, which is 
mounted on the fuselage and which provides power to twin pusher propellers 
72 mounted on rear region 16 of the fuselage. Propellers 72 provide 
forward thrust to the aircraft to achieve the desired airflow over the 
rotors to lift and maneuver the aircraft. As will be understood by those 
skilled in the art, any known power system may be used to provide the 
required lift to the aircraft. For example, the power system may include a 
forwardly mounted single propeller, a towing device, jet engines or the 
like. In the preferred embodiment, twin pusher propellers 72 provide a 
forward thrust to the gyroplane so as to facilitate forward cruising 
speeds of approximately 150 miles per hour when fully loaded with cargo 
and fuel. The fore and aft tilt of the fore and aft rotors is determined 
by the magnitude and direction of travel of the gyroplane relative to the 
air mass, wherein the direction of travel will generally will be in a 
forward direction. The travel of the gyroplane, however, due its 
maneuverability, may be in a sideways direction. 
Referring to FIG. 2, which is detailed perspective view of the control 
console of FIG. 1, control stick 26 is positioned directly forwardly of 
pilot's seat 23 and extends outwardly from console 30. Control stick 26 is 
capable of movement in a forward direction 74, a rearward direction 76, a 
port direction 78, a starboard direction 80 and in combinations thereof. 
Movement of the control stick in any of these directions is similar to the 
movement of a control stick in a standard fixed-wing aircraft such that a 
pilot trained to fly a standard fixed-wing aircraft would readily 
recognize the orientation and movement of control stick 26. The control 
console further includes trim control sticks 28 and 29, which operate to 
trim the position of the aft and fore rotors, respectively, during flight. 
Referring to FIG. 3, a control system 82 is depicted. FIG. 3 is a detailed 
view of the mechanics of control system 82, showing the connection between 
the rotors and the flight controls. Control system 82 includes a fore 
control system 83 and an aft control system 84 which control, 
respectively, fore rotor 38 and aft rotor 40. Forward rotor hub 52, which 
operates in the same manner as rearward rotor hub 54, includes rotor 
blades 44 which hang from a pin 85 secured within a bracket 86 that 
rotates on a bearing 87. Bearing 87 is attached to a control arm 88 which 
pivots on a pin 89 in a bracket 90. Bracket 90 pivots on a pin 91 in a 
bracket 92 which is attached to a mast 93 secured to the fuselage. Control 
arm 88 is fixed to a control arm 94 that pivots on control arms 95. 
Control stick 26 pivots on shafts 96 and 97. Shaft 96 and a shaft 98 
rotate in a bearing 99 wherein bearing 99 is fixed to the airframe. An 
elbow 100 pivots on shafts 97 and 98 wherein elbow 100 is fixed to a 
control arm 101 that pivots on control arms 95. Accordingly, movement of 
the handle of control stick 26 rearwardly in direction 76 will cause elbow 
100 to rotate in a direction 102 thereby forcing control arms 101 and 95 
in an upward direction 103. Upward movement of control arms 95 will cause 
attendant rotational movement of control arm 88 about pin 89 so as to tilt 
bearing 87 in rearward direction 76 thereby tilting the rotational axis of 
rotor blades 44 in a rearward direction. Similarly, forward tilting of 
control stick 26 in forward direction 74 will result in tilting of the 
rotational axis of rotor blades 44 in a forward direction. It will be 
appreciated by those of skill in the art, that although oily two rotor 
blades are depicted in association with hubs 52 and 54, the hubs may be 
constructed to accommodate large numbers of rotor blades. 
Still referring to FIG. 3, control of rearward rotor hub 5, will be 
described. Trim control stick 28 pivots on a pin 104 which is secured to 
the fuselage. The trim control stick is used to establish hands-off 
control of the gyroplane during flight so as to make slight adjustments 
during flight for the center of gravity, the load and the power setting of 
the gyroplane. In another embodiment, trim control stick 28 may include a 
twist type control stick as is commonly found on motorcycles. Trim control 
stick 28 pivots a push-pull rod 105 attached to an elbow 106 which pivots 
on a pin 107 secured to the fuselage. Elbow 106 pivots push-pull rod 108 
which pivots a control arm 109 on a pin 110 thus controlling the angle of 
attack of aft rotor set 40. Accordingly, movement of the handle of trim 
control stick 28 in forward direction 74 will cause elbow 106 to rotate in 
a direction 111 about pin 107 so as to move rod 108 downward thereby 
pivoting control arm 109 in a direction 112 about pin 110 and thereby 
tilting the rotational axis of rotor blades 46 in a forward direction. 
Foot pedals 32 include a port foot pedal 180 and a starboard foot pedal 182 
that are fixed to push-pull rods 113 and 114, respectively, which pivot 
with elbows 115 and 116, respectively. Elbows 115 and 116 are attached to 
the airframe at pivot pins 117 and 118, respectively, and pivot with a rod 
119. Rod 119 pivots with push-pull rods 120 and 121 which pivot, 
respectively, with control arms 122 and 123 (not shown). Control arms 122 
and 123 are fixed to a bracket 124 which pivots on a pin 125 thereby 
controlling the side to side angle of aft rotor set 40. Foot pedals 180 
and 182 are operatively connected so that forward movement of one pedal 
will cause attendant rearward movement of the other pedal. Accordingly, 
movement of port foot pedal 180 in a forward direction 184 will cause 
forward movement of rod 113 thereby rotating elbow 115 in a direction 126. 
Simultaneous with forward movement of foot pedal 180, foot pedal 182 will 
move in a rearward direction 186 and will cause rearward movement of rod 
114 thereby rotating elbow 116 in a direction 128. Movement of elbow 116 
in direction 128, and movement of elbow 115 in direction 126, will cause 
rod 119 to force rod 121 and control arm 123 to move in a downward 
direction 129 and will cause rod 120 and control arm 122 to move in an 
upward direction 130, thereby controlling the side to side angle of aft 
rotor set 40. Those skilled in the art will understand that blade tilting, 
in addition to or instead of rotor hub tilting, may be used in the 
gyroplane of the present invention wherein standard fixed wing controls 
are used to manipulate the blade tilting so as to facilitate operation of 
the gyroplane by fixed-wing aircraft pilots without additional extensive 
training. 
In another embodiment, the gyroplane controls of the present invention may 
be used to control the pitch angle of the individual blades as cyclic 
pitch control is used in helicopters to control the plane of rotation of 
the rotor blades. 
Referring to FIGS. 4A-4E, which are side views showing a descent of the 
gyroplane due to downward tilting movement of the forward rotor, the 
operation of descent of the gyroplane will be described. FIG. 4A shows 
gyroplane 10 in a steady state cruise wherein forward rotor 38 is 
positioned with its plane of rotation 58 at an angle 134 of approximately 
10.degree. from a level position (shown by the dash line) with respect to 
longitudinal axis 18 of the fuselage. Similarly, in this steady state 
cruise, rearward rotor 40 is positioned with its plane of rotation 60 at 
an angle 136 of approximately 10.degree. from a level position (shown by 
the dash line). In this position the rotors are not tilted to either side 
of the fuselage and the gyroplane experiences level, steady state flight 
in a forward, horizontal direction 137. 
The level position of each of the rotors is defined wherein the plane of 
rotation of the rotor is parallel to elongate axis 18 of the fuselage and 
perpendicular to the vertical axis of the corresponding rotor shaft. 
Accordingly, the angle of the rotors, also called the tilt angle, is 
defined relative to the fuselage of the gyroplane. As the fuselage is 
propelled forwardly by propellers 72 in forward direction 137, air 
impinges on the fuselage and the rotors in a direction 139. The acute 
angle formed between the plane of rotation of the rotors and the air that 
impinges on the rotors is defined as the angle of attack of the rotors. 
Accordingly, the angle of attack of the rotors is defined relative to the 
airflow through which the gyroplane travels. 
FIG. 4B shows gyroplane 10 beginning a descent. Specifically, forward 
movement of control stick 26 in direction 74 lowers the angle of attack of 
forward rotor 38. Decreasing the tilt angle of rotor 38 also lessens the 
angle of attack of the rotor thereby lessening the lift generated by the 
forward rotor. The decreased lift of the forward rotor downwardly pitches 
nose 14 of the fuselage about a pitch axis 140 of the fuselage. This 
downward pitching of fuselage 12 causes the angle of attack 144 of 
rearward rotor 40 to decrease such that the lift generated by rearward 
rotor 40 is decreased. In this manner, tail portion 16 of the fuselage 
also descends thereby tending to facilitate a full descent of the 
aircraft. 
FIG. 4C shows aft movement of control stick 26 in direction 76, which 
upwardly tilts the forward region of forward rotor 38 to increase its tilt 
angle to an angle 146 of approximately 10.degree.. This increases the 
angle of attack of the rotor and the lift generated by the forward rotor 
to pitch the nose of the aircraft upwardly about pitch axis 140 and to 
begin to bring the fuselage into a level orientation. 
FIG. 4D shows further rearward movement of the control stick to further 
increase the tilt angle of the forward rotor to an angle 147 of 
approximately 15. The increase in the tilt angle increases the angle of 
attack of the rotor, which causes upward movement of the nose of the 
gyroplane. The upward movement of the nose of the gyroplane causes the 
angle of attack of rearward rotor 40 to increase such that the lift 
generated by the rearward rotor is increased. In this manner, tail portion 
16 of the fuselage also begins to ascend thereby tending to facilitate a 
leveling of the aircraft. 
FIG. 4E shows forward movement of control stick 26 in direction 74, which 
downwardly tilts the forward region of forward rotor 38 to decrease its 
tilt angle to an angle 148 of approximately 10.degree.. This decreases the 
lift generated by the forward rotor to bring the fuselage into a level 
orientation. Accordingly, gyroplane 10 is returned to a steady state 
cruise wherein forward rotor 38 is positioned with its plane of rotation 
58 at the steady state cruise angle of approximately 10.degree. from a 
level position. Similarly, in this steady state cruise, rearward rotor 40 
is positioned with its plane of rotation 60 at an angle 150 of 
approximately 10 from a level position. During the descent process thus 
described, the tilt angle of the rear rotor is not changed. The angle of 
attack of the rear rotor, however, is changed due to the pitching movement 
of the fuselage about its pitching axis. Those skilled in the art will 
understand that other angles may also be utilized during a descent of the 
aircraft. Angles less than 30.degree. are preferred during high power 
thrust of the gyroplane but angles larger than 30.degree. may also be used 
during lower power thrust of the gyroplane. 
Referring to FIGS. 5A-5E, which are side views showing an ascent of the 
gyroplane due to upward tilting movement of the forward rotor, the 
operation of ascending the gyroplane will be described. FIG. 5A shows 
gyroplane 10 in a steady stale cruise wherein forward rotor 38 is 
positioned with its plane of rotation 58 at an angle 152 of approximately 
10.degree. from a level position (shown by the dash line) with respect to 
longitudinal axis 18 of the fuselage. Similarly, in this steady state 
cruise, rearward rotor 40 is positioned with its plane of rotation 60 at 
an angle 154 of approximately 10.degree. from a level position (shown by 
the (lash line). In this position the rotors are not tilted to either side 
of the fuselage and the gyroplane experiences level, steady state flight 
in forward, horizontal direction 137. As will be understood by one skilled 
in the art, the load, the center of gravity, and the power setting of the 
gyroplane may result in hands-off flight positioning of the longitudinal 
axis of the gyroplane fuselage at a pitched angle with respect to the 
horizon during steady state flight. 
FIG. 5B shows gyroplane 10 beginning an ascent. Specifically, rearward 
movement of control stick 26 in direction 76 tilts upward the forward 
region of forward rotor 38 to raise its tilt angle to an angle 155 of 
approximately 20.degree.. Increasing the tilt angle of rotor 38 also 
increases the angle of attack of the rotor thereby increasing the lift 
generated by the forward rotor. The increased lift of the forward rotor 
upwardly pitches nose 14 of the fuselage about pitch axis 140 of the 
fuselage. This upward pitching of fuselage 12 causes the angle of attack 
of rearward rotor 40 to increase such that the lift generated by rearward 
rotor 40 is increased. In this manner, tail portion 16 of the fuselage 
also ascends thereby tending to facilitate a full ascent of the aircraft 
so long as the airspeed of the aircraft is maintained. 
FIG. 5C shows forward movement of control stick 26 in direction 74, which 
downwardly tilts the forward region of forward rotor 38 to decrease its 
tilt angle to an angle 156 of approximately 10.degree.. This decreases the 
angle of attack of the rotor and the lift generated by the forward rotor 
to pitch the nose of the aircraft downwardly about pitch axis 140 and to 
begin to bring the fuselage into a level orientation. 
FIG. 5D shows further forward movement of the control stick to further 
decrease the tilt angle of the forward rotor to an angle 158 of 
approximately 5.degree.. The decrease in the tilt angle decreases the 
angle of attack of the rotor, which causes downward movement of the nose 
of the gyroplane. The downward movement of the nose of the gyroplane 
causes the angle of attack of rearward rotor 40 to decrease such that the 
lift generated by the rearward rotor is decreased. In this manner, tail 
portion 16 of the fuselage also stops climbing, thereby tending to 
facilitate a leveling of the aircraft. 
FIG. 5E shows rearward movement of control stick 26 in direction 76, which 
upwardly tilts the forward region of forward rotor 38 to increase its tilt 
angle to an angle 160 of approximately 10.degree.. This increases the lift 
generated by the forward rotor to bring the fuselage into a level 
orientation. Accordingly, gyroplane 10 is returned to a steady state 
cruise wherein forward rotor 38 is positioned with its plane of rotation 
58 at the steady state cruise angle of approximately 10.degree. from a 
level position. Similarly, in this steady state cruise, rearward rotor 40 
is positioned with its plane of rotation 60 at an angle 162 of 
approximately 10.degree. from a level position. During the ascent process 
thus described, the tilt angle of the rear rotor is not changed. The angle 
of attack of the rear rotor, however, is changed due to the pitching 
movement of the fuselage about its pitching axis. Those skilled in the art 
will understand that other angles may also be utilized during the ascent 
procedure of the aircraft. 
Referring to FIGS. 6A-6D, which are front views showing a port turn of the 
gyroplane due to port tilting movement of the forward rotor, turning of 
the gyroplane will be described. FIG. 6A shows gyroplane 10 in a steady 
state cruise wherein rotors 38 and 40 are in a cruising position such that 
the planes of rotation 58 and 60 of the rotors are positioned generally at 
a forward angle of approximately 10.degree. to longitudinal axis 18 and 
such that the rotors are not tilted to either side of the fuselage. In 
this position the rotors do not impart a turning force to fuselage 12 such 
that the longitudinal axis 18 of the fuselage is aligned with the 
direction of travel of the gyroplane. 
FIG. 6B shows movement of the control stick in direction 78 to port side 
164 of fuselage 12 which causes attendant tilting of forward rotor 38 to 
the port side of the fuselage. The forward rotor is shown tilted at a tilt 
angle 166 of approximately 10.degree. from its neutral position. This 
tilting movement of the forward rotor results in a force to yaw the 
aircraft in port direction 78 about a central vertical axis 168 of the 
fuselage. The yawing force is equal to the lift multiplied by the sine of 
the tilt angle. Those skilled in the art will understand that central 
vertical axis 168 is generally aligned with the center of gravity along 
the longitudinal axis of the fuselage which may vary according to loads 
held within the fuselage and with the positioning and manipulation of the 
rotors. 
FIG. 6C shows banking movement of the aircraft fuselage due to the 
centrifugal force resulting from turning of the aircraft. This centrifugal 
force is due to the pendulum effect of the fuselage, which is suspended 
from rotor hubs 52 and 54. The pitch axis and the yaw axis of the 
gyroplane typically are located between the fore and aft rotors. The exact 
positioning of the pitch axis and the yaw axis of the gyroplane depends, 
however, on the exact control mechanism used as well as the load, center 
of gravity, and positioning and setting of the power system. 
FIG. 6D shows return of the control stick to a neutral position to return 
forward rotor 38 to an un-tilted position. Return of the forward rotor to 
the neutral position removes the yawing force on the fuselage so that the 
aircraft will maintain its new heading in a direction 170. Those skilled 
in the art will understand that tilting the rotor in a starboard direction 
will result in a turning force to move the aircraft in a corresponding 
starboard direction. Those skilled in the art will also understand that 
other angles may be utilized during the turning procedure of the aircraft. 
Referring to FIG. 7, which is a detailed perspective view of the foot 
pedals of FIG. 1, pair of foot pedals 32 includes port side foot pedal 180 
and starboard side foot pedal 182. The foot pedals are positioned directly 
forwardly of pilot's seat 23 and extend upwardly from floor 34 of the 
fuselage. Each of the foot pedals is capable of movement in a forward 
direction 184 and a rearward direction 186, respectively. Movement of one 
of the foot pedals in the forward direction is similar to the movement of 
one of the foot pedals in a standard fixed-wing aircraft such that a pilot 
trained to fly a standard fixed-wing aircraft would readily recognize the 
orientation and movement of foot pedals 180 and 182. 
Referring to FIGS. 8A-8D, which are side views showing a port yaw of the 
gyroplane due to starboard tilting movement of the rearward rotor, turning 
of the gyroplane will be described. FIG. 8A shows gyroplane 10 in a steady 
state cruise wherein rotors 38 and 40 are in a cruising position such that 
planes of rotation 58 and 60 of the rotors are each positioned generally 
at an angle of approximately 10.degree. to longitudinal axis 18, and such 
that the rotors are not tilted to either side of the fuselage. In this 
position the rotors do not impart a yawing force to fuselage 12 so that 
longitudinal axis 18 of the fuselage is aligned with the direction of 
travel of the gyroplane. 
FIG. 8B shows forward movement of port side foot pedal 180 in direction 
184, which causes attendant tilting of rearward rotor 40 toward a 
starboard side 188 of the fuselage. The rearward rotor is shown tilted at 
an angle 190 of approximately 10.degree. from its neutral position. Those 
skilled in the art will understand that other angles may be utilized 
during the turning procedure of the aircraft. This tilting movement of the 
aft rotor results in a force to yaw the aircraft in port direction 78 
about central vertical axis 168 of the fuselage. The yawing force is equal 
to the lift multiplied by the sine of the tilt angle. Those skilled in the 
art will also understand that central vertical axis 168 is generally 
aligned with the center of gravity of the fuselage which may vary along 
the longitudinal axis of the fuselage according to loads held within the 
fuselage and with the positioning and manipulation of the rotors. 
FIG. 8C shows the turning movement of the aircraft fuselage due to the 
yawing force resulting from tilting of the aft rotor. Specifically, nose 
14 of the fuselage is moved in port direction 78 due to the forward 
movement of port foot pedal 180. 
FIG. 8D shows return of the port foot pedal to a neutral position, such as 
by a spring force acting on the pedal, upon the release of pressure from 
the pedal. Returning the port foot pedal to the neutral position returns 
aft rotor 40 to an un-tilted position thereby removing the yawing force on 
the fuselage of the aircraft. In the turned orientation starboard side 188 
of the fuselage is exposed to air that moves rearwardly past the fuselage 
as the aircraft is propelled forwardly. The large side area of the 
aircraft functions as a vertical stabilizer to return the aircraft to a 
nose first attitude such that longitudinal axis 18 is aligned with the 
direction of travel. In another embodiment, a vertical stabilizer may be 
added to the tail region of the fuselage so as to return the aircraft to a 
nose first attitude. Those skilled in the art will understand that 
depressing the starboard foot pedal in the forward direction will result 
in a yawing force to move the aircraft in a corresponding starboard 
direction. Steering of the gyroplane by use of the foot pedals is feasible 
due to the low speeds at which the gyroplane may be operated. 
Referring to FIG. 9, which is a detailed perspective view of the trim 
control stick of FIG. 1, trim control stick 28 is capable of movement in 
forward direction 74 and in rearward direction 76. Manipulation of the 
trim control stick in directions 74 and 76 causes attendant forward and 
rearward tilting of the rearward rotor, respectively, with respect to the 
aircraft fuselage so as to trim the aircraft during flight. In a similar 
manner, trim control stick 29 trims the position of the forward rotor. In 
the preferred embodiment, trim control stick 29 is a joystick that may by 
manipulated in forward, rearward, and sideways directions so as to 
correspondingly trim the forward rotor set. 
Referring to FIGS. 10A-10C, which are side views showing trimming of the 
gyroplane due to upward tilting movement of the forward rotor and downward 
tilting movement of the rearward rotor, trimming of the gyroplane will be 
described. Specifically, slight changes in the tilt angle of the rotors 
are affected by trim control sticks 28 and 29 such that slight changes in 
the lift of the rotors, as determined by the angle of attack of each 
rotor, are used to compensate for variations in the location of the 
longitudinal center of gravity of the aircraft. FIG. 10A shows gyroplane 
10 in a steady state cruise wherein rotors 38 and 40 are in a cruising 
orientation such that planes of rotation 58 and 60 of the rotors are 
positioned generally at an angle 192 and 194, respectively, of 
approximately 10.degree. to longitudinal axis 18 and such that the rotors 
are not tilted to either side of the fuselage. In this position the rotors 
do not impart a pitching or a yawing force to fuselage 12 so that the 
longitudinal axis 18 of the fuselage is aligned with direction of travel 
196 of the gyroplane. 
FIG. 10B depicts a situation where forward displacement of the longitudinal 
center of gravity 198 of the aircraft, possibly resulting from cargo 
loading or fuel burn-off, from a first position 199. This forward 
displacement results in nose 14 of the aircraft lowering in a direction 
198 and tail 16 of the aircraft raising in a direction 200. The tail of 
the aircraft raises enough to decrease the angle of attack of the rearward 
rotor to equal the de creased load the aft rotor must lift. In this 
situation, the pilot maintains the altitude of the aircraft by moving fore 
rotor trim control stick 29 in rearward direction 76 to increase the tilt 
angle of the forward rotor to an angle 202 of approximately 17.degree. so 
as to increase the angle of attack on the forward rotor. This increase in 
the angle of attack of the forward rotor acts to carry the increased load 
on the forward rotor due to the forward shifting of the longitudinal 
center of gravity of the aircraft. 
FIG. 10C shows trimming of the aircraft while maintaining altitude by 
decreasing the tilt angle of the aft rotor. The tilt angle of the aft 
rotor is decreased to an angle 204 of approximately 8 by forward movement 
of aft rotor trim control stick 28 in direction 74. Decreasing the tilt 
angle of the aft rotor decreases the angle of attack of the rearward rotor 
so as to level the aircraft. The increase or decrease in the tilt angle of 
either of the rotors can be on the order of 1.degree. to achieve the 
desired trimming of the aircraft when the longitudinal center of gravity 
of the aircraft is moved forwardly or rearwardly within the aircraft. 
Referring to FIG. 11, which is a detailed perspective view of another 
embodiment of the flight controls of the gyroplane of the present 
invention, the flight controls may include a "wireless" flight control 
system, similar to the wireless flight control system of a standard 
fixed-wing aircraft, wherein the pilot inputs the desired pitch, roll and 
yaw characteristics to an onboard computer system via a touch activated 
control console 206. The preferred embodiment of the gyroplane of the 
present invention, however, uses the fly-by-wire system as described, due 
to its low mechanical failure rate. 
FIG. 12 is a perspective view of a preferred embodiment of the gyroplane of 
the present invention showing the external shape of the fuselage of the 
gyroplane and externally mounted power units 70. 
While preferred embodiments of the present invention have been shown and 
described, it will be apparent to those skilled in the art that many 
further variations and modifications may be made without departing from 
the scope of the invention as defined in the appended claims, which are 
intended to cover all such changes and modifications as fall within the 
scope of the invention.