US2110516A

US2110516A - Airplane

Info

Publication number: US2110516A
Application number: US185634A
Authority: US
Inventors: Fred E Weick
Original assignee: Fred E Weick & Associates Inc
Current assignee: Fred E Weick & Associates Inc
Priority date: 1938-01-18
Filing date: 1938-01-18
Publication date: 1938-03-08
Anticipated expiration: 1955-03-08

Description

F. E. WEICK AIRPLANE March 8, 1938.

Filed Jan. 18', 1938 5 Sheets-Sheet l March 8, 1938. F, w cK 2,110,516

AIRPLANE Filed Jan. 18, 1958 5 Sheets-Sheet 2 i 3448. um

March 8, 1938. F. E. wElcK 2,110,516

AIRiLANE Filed Jan. 18, 1938 5 Sheets-Sheet 3 F. E. WEICK AIRPLANE March 8, 1938.

Filed Jan. 18, 1958 5 Sheets-Sheet 4 F. E. WEICK March 8, 1938.

AIRPLANE Filed Jan. 18, 1938 5 Sheets-Sheet 5 Patented Mar. 8, 1938 PATENT. OFFICE AIRPLANE Fred E. Weick, Bethesda, Md.,

assignor to Fred E. Weick & Associates, Inc., Hampton, Va., a corporation of Virginia Application January 18, 1938, Serial No. 185,634

17 Claims.

This invention relates to certain new and useful improvements in airplanes; and the nature and objects of the invention will be apparent to and readily understood by those skilled in the art in the light of the following explanation and detailed description of the accompanying drawings illustrating what I believe to be the preferred embodiments or aerodynamical and mechanical expressions of my invention, from among various other forms, embodiments, designs, combinations and constructions of which the invention is capable within the spirit and the scope thereof.

This application is a substitute for and continuation in part of the pending application filed by me July 5, 1934:, Serial No. 733,898, for

improvements in airplanes.

Fundamentally itis a general aim and a primary object of my present invention to reduce or substantially eliminate the basic hazards and dangers that result from certain features and characteristics inherent in the prevailing designs and types of conventional heavier-than-air craft, or airplanes as such craft are generically 1 termed herein. It is generally recognized and established that the conventionalairplane, be-

cause of such inherent dangers and hazards, can

only be practically piloted with any degree of safety under the varying conditions encountered ggylll flight and in taking off and landing, by highly trained and skillful pilots; and that the general use of the conventional airplane is therefore restricted to those having the time and finances for the training and the ability to successfully acquire from such training the necessary and essential piloting technique and skill for safety in flight.

One of the major hazards of the conventional airplane is thelanding operation which requires delicate and skillful handling of the airplane,

and excellent vision and a high degree of depth perception from the pilot to successfully carry out. This'hazard isa direct result of the inability of the conventional airplane to land steeply because of a flat glide and of high landing speed with a long landing run, and further due to the difficulty of contacting the ground accurately at a desired point because of the limited range of gliding angles available to the pilot,

even by side slipping the airplane.

A feature of an airplane of my present invention resides in adesign providing an airplane that cannot be stalled and has a wide range of gliding angles available to the pilot, and also has 7 low landing speed and a short landing run on the ground, which together with lateral control and stability at all speeds and angles, results in the substantial elimination of the landing hazard because practically no skill is required to accurately maneuver and land the air- 6 plane even on small landing areas and over the usual landing area border obstructions.

Another feature of the invention which contributes to the safety of landing and to the ease of pilot handling on the ground, is presented by 10 my design and arrangement of the landing gear in which provision is made for absorbing the maximum vertical landing velocities and for preventing nosing over or ground looping under any conditions of landing that may be encounl5 tered; and further in which the landing surface engaging elements are arranged so that the landing gear is directionally stable and upon landing surface contact always causes the airplane to tend to follow the direction of landing instead of 2 a path defined by the fore and aft axis or direction in which the airplane is headed, unless the direction of landing is along such axis.

A further feature of the invention is presented by the relative arrangement of the directionally g5 stable landing gear, the body of the airplane and the lifting surface therefor by which the airplane in normal position supported on the ground by the landing gear is in substantially normal cruising flight attitude with the body in substantial horizontal position and the lifting surface is at a relatively small angle of incidence, that is, substantially the angle of incidence for cruising flight.

Another feature resides in the combination with the above arrangement of landing gear, body and lifting surface, of means for increasing the lift coeflicient of the lifting surface for take off of the airplane without substantially changing the normal cruising flight attitude of the airplane with the body maintained in substantially horizontal position and the lifting surface at the relatively small angle of incidence, during take off of the airplane.

The conventional airplane essentially has three controls, that is, directional (rudder), lateral (ailerons), and longitudinal (elevator). Such three controls are required in order that the conventional airplane may operably meet all of the conditions encountered in flight operations, as for example, in landing in a cross wind, or in making a landing under conditions that necessitate side slipping the airplane. Generally, the directional or rudder control is operated by thepilots feet, while the lateral and longitudinal controls are operated manually by the pilot, so that, the pilot must acquire the essential skill and ability to coordinate and synchronize the operation of these controls through his feet and hands. Experience has established the fact that such coordination is diflicult to acquire and that crossing or improper coordination of the controls, particularly when flying close to the ground, is a frequent cause of serious accidents with the conventional airplane.

An important feature and a characteristic of this invention is the provision of a basic design of airplane in which but two controls are required for flight operations, both in the air and in landing and taking off, under all conditions encountered, with the resulting elimination of the difiiculties of coordinating and synchronizing three controls as in the conventional airplane, and if desired the elimination of a foot operated control to thereby avoid the necessity of coordinating not only a plurality of controls but also in coordinating and synchronizing the feet and hands in operating such controls.

An airplane design of my invention is further featured by lateral stabiliy and lateral control for and throughout'the entire range of speed and angles of attack, to thereby eliminate the dangerous characteristics encountered in the conventional airplane due to lateral instability at low speeds and angles of attack at and approaching the stall, and the insuflicient lateral control for the conventional airplane under such flight conditions.

Another feature embodied in a design of airplane of this invention in combination and aerodynamic cooperation with the other features thereof, that contributes to the safety and reduces the piloting skill required, resides in eliminating that characteristic generally found in the conventional airplane of balance at higher angles-of attack with power-on than with poweroff, by providing in the design for balance at a slightly lower angle of attack with power-on than with power-off to thereby avoid the possibi1 ity of losing altitude when it is desired to climb, while always insuring climb when full power is applied with the airplane below the maximum level flight speed.

Afufther general object and a feature of my invention is the provision for maximum range of vision for the pilot, especially in a forward and downward direction, in a design of airplane having the foregoing characteristics for safety by reducing the piloting skill required; and further in the provisions for comfort and reduction of fire hazard, and all of the foregoing in a design thatis adapted for relatively low cost production and that is capable of minimum upkeep and operating costs in use.

With the above general features, characteristics and objects in view, as well as certain other features and characteristics that will appear and be readily recognized in the following description, my invention consists in certain novel features in design and in combination and arrangements of aerodynamic and structural elements and parts, all as will be more fully and particularly referred to and specified hereinafter.

Referring to the accompanying drawings in which similar reference characterers refer to corresponding elements and parts throughout the several figures:

Fig. 1 is a top plan view of a design of airplane embodying the principles and features of my invention.

Fig. 2 is a view in front elevation of the airplane of Fig. 1.

Fig. 3 is a view inside elevation of the airplane ally stable forward landing wheel and its steerable connection into the control system.

Fig. 5 is a detail perspective view of the for- Ward, directionally stable wheel of the landing gear of the invention, and an arrangement for steering said wheel from the airplane control system. 3

Fig. 6 is a schematic view in perspective of an alternative two-control system utilizing rudders and elevator, the rudders and elevator being diagrammatically shown in outline.

Fig. 7 is a schematic view in perspective of another form and arrangement of two control system utilizing'an elevator, rudders and ailerons with the rudders and ailerons connected for simultaneous operation as a single control.

As an example of one aerodynamic and structural design expression of the principles, features and characteristics of. my invention, I have illustrated in the accompanying drawings, a small, light-weight and relatively low cost airplane of the two-place, high monoplane wing type, that is particularly adapted for general private owner and novice pilot use because -of the inherent safety characteristics and low degree of piloting skill required to operate it with safety as compared to the conventional airplane. I have selected the illustrated design of airplane einbodying the invention, primarily because an airplane of this general design and type embodying certain of the basic features hereof has been constructed and flight tested and the safety characteristics and the low degree of piloting skill required satisfactorily indicated.

However, there is no desire or intention to limit the invention in all and its various features and characteristics to embodiment in a design and type of airplane of the example hereof. It is recognized and intended that the invention can be embodied in and expressed by various other designs and types of airplanes, as will be apparent to those skilled in the art, and my present invention includes all of such embodiments and adaptations within the broad spirit and scope of the invention.

The design of the illustrated embodiment of my invention is of the high monoplane wing type having an outrigged tail and a pusher propeller and includes the body B, high monoplane wing W and the outrigged tail or empennage E carried from the wing W. The body B is of the closed cabin or nacelle type in which the occupants are enclosed in an upwardly extended, light-weight cabin portion C with a forward windshield and side window arrangement that affords particularly good vision out of the forward side windows for the pilot. The body B and its cabin portion C enclose two seats, in this instance, the forward one S of which is shown as providing the preferable pilot's seat from which the airplane is flown.

The wing W is mounted as and provides a high monoplane wing that extends across the upper or top side of the cabin structure C and above the main body B as defined by the portion of such body that extends forwardly of cabin structure C. The wing W terminates forwardly with its leading edge structure or portion spaced rearwardly from the forward end of body B, and also preferably as here shown, terminating at or short of the forward side of cabin structure C. The trailing edge portion of wing W is disposed preferably to the rear of or approximately at and above the rear or tail end of body B as will be clear by reference to Figs. 1 and 3, although the design is not essentially limited to such relative positions of body and wing. Preferably, the wing W has a decided dihedral angle, as clearly shown by Fig. 2 of the drawings, for a purpose to be hereinafter explained.

Outrigger girders or spars I are mounted and supported from the wing structure W spaced from opposite sides, respectively, of body B, and extend rearwardly from the wing in substantially parallel relation. The rear ends of the outrigger girders l0 mount and carry thereon an em'pennage E, that consists in the present example of the spaced vertical fins or stabilizers l I mounted on the spars Ill and extending thereabove and therebelow, the horizontal stabilizer l2 extending across and between spars Ill, and the vertically swingable elevator Hi pivotally mounted along the trailing edge of stabilizer l2 and between girders l0 and fins ll.

A motor M is mounted on the rear portion of body B, preferably the upper portion thereof and along the fore and aft axis of the body, and drives a pusher propeller P whichis disposed and positioned between the outrigger girders or spars ID, the central section of the wing W between the spars l0 being preferably cut away a distance forwardly as shown by Fig. 1 of the drawings. The design thus presents an initial safety feature in locating the propeller P as 'surrounded and guarded by the wing and body at the forward side, the girders ill at the opposite lateral sides and the empennage E at the rear side, so that injury from inadvertent contact with the propeller when the airplane is on the ground is practically eliminated.

The landing gear for the airplane, which in this example happens to be of the land type,

consists of the spaced rear wheels l5 having a very wide tread and disposed at opposite sides of the rear portion of body B beneath wing W and aft of the center of gravity (c. g. of Fig. 3) of the airplane, and the forward wheel l6 mounted at the forward end of body B along the longitudinal axis of the airplane and forward of its center of gravity. These wheels are each of the so-called air wheel type familiar in the art and capableof withstanding considerable side loads without failure. The arrangement of the wheels I5 and iii of the landing gear relative to the body B and the lifting surface W is such that in normal position supported on the ground by the landing gear (see Fig. 3), the airplane is in substantially normal cruising flight attitude with the body B in substantially horizontal position with its longitudinal axis approximately parallel to the ground and with the lifting surface W at the relatively smaillangle of incidence for cruising flight. The mounting and relative arrangement and operation of this landing gear and the wheels l5 and 16 thereof form impor:

tant features of my invention and will be referred to andexplained in detail hereinafter.

Basically, according to an airplane design of my present invention, the landing and take of! difliculties and hazards of the conventional airplane, are -materially reduced by providing for a wide range of glide angles and a steep angle of climb. I attain the desired result by designing the wing W of a so-called high lift" type having a high drag and by which the airplane can attain a steep angle of glide with a relatively low rate of vertical descent. The type of high lift wing W here selected embodies an auxiliary airfoil A fixed in a certain spaced relation forwardly of and along the leading edge of wing W, and by which, as familiar to those skilled in the art, a high drag and lift can be obtained. Attention is specifically directed at this point to the fact that my invention is not limitedor restricted to any particular form and type of high-lift wing, or wing to give the required increase in drag and lift, as wings of the flap or slotted or other suitable types may be employed if desired or found expedient.

For example, I have in the present instance, included trailing edge flaps F on the wing W of the manually operated and controlled type, and such flapscan be efiiciently used in conjunction with the type of high lift wing W, or a wing of the automatically operating flap type can be substituted for wing W. In connection with the flaps F here shown, I have purely diagrammatically and without regard to efiicient location, illustrated in Fig. 3 of the drawings a manual control for operating flaps F, which flaps are suitably connected together for simultaneous raising and lowering. The manual control may include the operating hand lever II in the body B accessible to the pilot, connected with and operating bell ..,crank l8 by the push-pull tube l9, which bellcrank is connected to the flaps F by the tubes 20 operatively connected to and coupled by a suitable bell crank (not shown) in the wing. Primarily, in the design of this example, the manually controlled flaps F are provided for selective use by a pilotif he finds it is diflicult to accustom himself to the normal action for the design of this example with its wing W, of pulling the control stick back to increase the angle of glide in the landing maneuver. By using the flaps F, the angle of glide can be satisfactorily adjusted in landing, through operation of the control lever I1, as will be readily understood by one skilled in this art.

As lateral instability at high angles and low speeds is a primary danger in conventional airplanes, I have by my present invention insured lateral stability and control throughout the entire range of speeds and angles of attack'which can be maintained in, fiight. In the illustrated example, I have accomplished this by providing sufficient longitudinal stability in the airplane, and by limiting the upward travel of the longitudinal control of elevator M to a point where the airplane not only cannot be maintained in a stall but, also cannot be forced into a spin. Such longitudinal control limitation .is fully discussed in United States Letters Patent No.'1,848,037 issued to me March 1, 1932, and'it will suffice to here state that the upward travel of elevator l4- in the present design is limited in any suitable manner, such for example as disclosed in my aforesaid patent, to a point where the airplane cannot be maintained in a stall or forced into a. spin. In the present design with the high is found present and available throughout the flight range.

The problem of lateral control at and beyond the stall, inherent in the conventional airplane, is eliminated from an airplane designed in accordance with this invention, because of the longitudinal control and stability relationship and the inability of the airplane to be flown or maintained at the stall. Therefore, conventional or other lateral control means may be employed for the design and satisfactory lateral control is insured therefrom at all speeds and angles of attack at which the airplane may be flown.

By the design and arrangement, in cooperation, of the high lift wing W and the limitation of upward travel of elevator l4, together with lateral stability and control throughout the range of speed and angles of attack, the airplane requires no particular skill to land it, other than maneuvering to contact the ground at the desired point. The wide range of gliding angles including a steep angle of glide make the landing approach an easy maneuver calling for'no particular or special degree of skill. The airplane will itself practically take care of contact with the ground without particular attention on the part of the pilot, and if landed with its wings approximately level laterally at any speed within approximately 30 miles per hour of the minimum speed, the landing will be safe Whether the airplane is leveled off before ground contact or continued in the glide straight to the ground, with the landing gear of the present examplathat embodies certain important features of the present invention.

The landing gear as hereinbefore referred to includes the rear wheels l5 behind, and the forward wheel I6 ahead, of the center of gravity of the airplane and so arranged and mounted as to make it practically impossible for the airplane to nose over. The rear Wheels l5 are preferably provided with the usual or any suitable brakes (not shown) but even with a full application of the brakes the arrangement of the landing gear is such as to prevent the airplane nosing over. The rear wheels l5 are disposed spaced 2. wide distance apart at opposite sides of and spaced from the body B toward the rear thereof and behind the center of gravity of the airplane (see Fig. 3). Each rear wheel i5 is mounted on a truss 2| extended laterally from the adjacent side of body B and mounted for swinging thereon to permit vertical movement of the 'wheel, and a long travel shock absorbing strut 22 extending between truss 2| and the wing W there- 1 above.

In accordance with the invention, the forward landing wheel l6 of the landing gear is mounted and arranged so as to be normally freely laterally swingable or castering for cooperation with the directionally fixed rear landing wheels l5 to provide the directionally stable landing gear for the airplane. I have disclosed herein one possible form of mounting and arrangement to attain the lateral swinging or castering operation of the forward landing wheel IS, in which example, the forward wheel I6 is carried by a long travel shock absorbing strut that includes the upper section 23 mounted in the nose or forward end of the structural frame of body B, referring now to Figs. 4 and 5 of the drawings in particular, and the lower section 24 rotatable and also vertically movable in the upper section. The lower end of the strut section 24 is provided with the fork 24a in which the forward landing wheel H5 is mounted and by which the wheel is vertically movable and laterally swingable or rotatable to carry out its castering function. The shock absorbing strut 2324 that mounts and carries forward wheel 16 is mounted on the body B in fixed position with its vertical axis inclined rearwardly, for example, a rearward inclination of approximately twenty degrees (20") may be used. The forward wheel I6 is thus mounted and arranged so that the area of landing surface contact of the wheel is to the rear of the point at which the projection of the rearwardly inclined vertically disposed axis about which the wheel rotates meets the landing surface, and, as a result, this forward landing wheel will function to caster or rotate into the direction of travel. The normally freely castering forward landing wheel 16 cooperates with the directionally fixed rear wheels l5 that are located aft of the center of gravity of the airplane, in such a manner that upon ground contact of the landing gear the caster-ing front wheel 16 will caster or rotate into the direction of travel of the airplane. For example, in landing the airplane with such directionally stable landing gear, if the airplane is landing with side drift, then immediately upon ground contact of the gear, the front wheel 5 will caster or rotate into the direction of travel of the airplane and in cooperation with the directionally fixed rear wheels, automatically turn or head the side drifting airplane into the direction of travel.

Such a directionally stable landing gear also enables accurate handling of the airplane in taxiing on the ground and substantially eliminates any tendency of the airplane to ground loop.

The shock absorbing mountings for the front and rear wheels of the landing gear, consisting of the shock absorbing struts 22 and 23-24, have a long vertical travel to sustain and absorb the landing loads at the maximum vertical velocities of landing. As the rear wheels l5 sustain the largest load, their shock absorbing struts have a greater vertical travel than the strut 2324 for the directionally stable front wheel I6. In Figs. 2 and 3 of the drawings the maximum vertical positions of the landing wheels with the shock absorbing struts collapsed are shown in dotted lines while the lowered positions of the wheels with the struts extended are shown in full lines. In connection with the travel of the shock absorbing means and landing wheels, I have found that with an airplane of the invention weighing approximately 1150 pounds, the landing gear should be capable of withstanding a vertical velocity of about 25 feet per second, and an 18 inch vertical travel for rear wheel shock absorbers 22 with a 12 inch travel for front wheel shock absorber 23-24, should be satisfactory.

While in the specific example hereof, I have shown a three wheel landing gear with a single forward directionally stable wheel l6, it is to be clearly understood that my invention includes a plurality of forward directionally stable landing wheels, spaced as may be desirable, and with or without the disclosed arrangement of directionally flxed rear wheels. Also, attention is called to the fact that other landing surface engaging elements than wheels may be employed including skis, water landing members such as floats, pontoons and the like, as the invention is in no sense limited to ground engaging landing wheels.

As a further feature of the invention, the forward landing wheel I6 is made steerable for ground handling and taxiing of the airplane, and

, materially simplify the process of learning to fly,

mounted for lateral swinging on a vertical shaft 26 on which it is mounted at its rear end. A brace or truss 25a is preferably mounted extended. between the forward end of arm 25 and the lower end of shaft 26, the shaft 26 being of course suitably mounted for. rotation around a vertical axis in fixed position in the body B. A rod or link 21 having a bifurcated forward end pivotally connected to the wheel fork 24a, extends rearwardly upwardly and. freely slidably through a vertically disposed guide 28 mounted on the forward end of laterally swingable arm 25. The guide 2% is plvotally mounted on the arm 25 for free rotation about a vertical axis.

By swinging arm 25 to the right or left the rod 21 is swung to rotate or turn the front, directionally stable landing wheel Hi to the right or left to steer the airplane when on the ground. The pivotal mounting of rod 21 to wheel fork 24a permits af free vertical travel of the shock absorber section 24, and the pivotal mounting of guide 23 permits free lateral swinging of arm 25 and rod 21 while operatively coupled. Steering operation or movement of arm 25 is carried out in the present example by and from the pilot's control system for the airplane, as will be described and explained hereinafter.

An important feature of the invention made possible by the basic design and directionally stable landing gear, is the use of but two controls by the pilot for complete flight, landing and take-ofi operation under all the varying conditions encountered in such operations. By this feature, either the rudder or directional control, or the aileron or lateral control of the conventional three-control system may be eliminated. In the preferred design and control arrangement hereof, as diagrammatically illustrated in Fig. 4 of the drawings, the airplane is provided with only a longitudinal or elevator control and a single control for changing the direction of flight, the conventional rudder control being eliminated. Such two-controls do away with the possibility of crossing controls and particularly eliminating the necessity for coordinating foot and manual control operating members.

The airplane in the form of Figs. 1 to 5 hereof is provided with the fixed, preferably adjustable, horizontal stabilizer l2 with the usual vertically swingable elevator M for longitudinal control. The usual rudder or directional control is eliminated and fixed vertical fins ll of sufiicient area for directional stability are provided carried at the tail of the airplane on the outrigger l0. Directional and'lateral control, that is, control in yaw and roll, is obtained from the wing mounted opposite control surfaces. 30, which in this instance are of the so-called spoiler type familiar in the art. Such spoilers 30 are mounted on opposite wings in the upper surface thereof and are difierentially vertically swingable to raised position and to lowered position within the wing. The spoilers 33 give a yawning moment similar to that given by a rudder and also at the same time give a rolling moment for lateral control.

A pilot operated control system for operating the two-control arrangement described, is illustrated in Fig. 4, of the drawings, and includes a usual pivotally mounted control column 3i 110":-

as hereinbefore described,

cables 50 and M,

able or swingable fore and aft of the airplane for longitudinal control, andmounting at its upper end a control wheel 32 rotatable for directional control. The control column 3| is mounted in position for operation by the pilot from forward seat S and is'pivotally mounted for fore and aft rocking about the pivot 3la.

Control cables

33 and 34 are connected to column 3| and below pivot 3la, respectively, and are extended rearwardly over suitable pulleys to guide them along outrigger girders iii to the upper and lower ends of the elevator horn Me, so that, forward movement of the control column will lower the elevator and rearward movement thereof will raise the elevator.

The hand wheel 32 on the upper end of control column 3| rotates a drum 32a, to which the

opposite cables

35 and 36 are connected and from which

cables

35 and 35 extend and are guided over suitable pulleys to the inner or lower ends of the horns 31 of opposite spoilers 30, respectively, within wing W. The upper ends of the spoiler horns 31 above the wing are connected in the usual manner by a cable 38 guided over suitable pulleys into and through the wing. By rotating wheel 32 to the ri ht and left spoilers 3|! are differentially vertic lly swung to directionally control the airplane to the right or left andat the same time generate a rolling moment acting in the proper direction.

If desired, conventional ailerons can be used in place of the spoilers 33, but due to the improved yaw characteristics from the spoilers the latter are preferred. 7

With the directionally stable landing gear of the invention, and the other characteristics of the design giving the high drag and lift with steep angle of glide and low landing speed and short landing run together with lateral stability and control throughout the range of speed and angles of attack, the two-control system as described gives full control for flight and for landing and taking ofi under all conditions and even in cross winds and with side drift.

The directionally stable forward landing wheel is steerably connected into the pilot's control system, and in the example hereof as shown in Figs. 4 and 5, this is accomplished by connecting opposite sides of the swingable arm 25 with the opposite

spoiler operating cables

35 and 36 by the respectively. Cables 40 and M are connected to opposite sides of arm 25 and then extended around opposite pairs of pulleys and connected to

cables

35 and 36 leading to and operated 'by hand wheel 32. Thus, as the hand wheel 32 is turned to the right or left with the airplane on the ground, the directionally stable landing gear I6 is turned to the right or left to steer the airplane in handling or taxying in movement on the ground. 01' course, a separate steering control can'be provided for front wheel IE, or this wheel can be unconnected and selfturning or castering if desired, but preferably, the steerable and directionally stable landing gear wheel i6 is operatively coupled with the pilot's control for ground steering.

The two controls made possible by the design ment of a two-control system for\t he airplane of the present example, which provides the elevator M for longitudinal control and the rudders 45 swingably mounted in the usual manner along the trailing edges of the vertical fins H on the outrigger girders Ill. The elevator I4 is operatively coupled to control column 3| by cables 33 and. 34, as explained in connection with Fig. 4, while the rudders 45 are connected by

cables

46 and 41 with the drum 32a of the control wheel 32.

Cables

46 and 41 extend over and are guided by suitable pulleys, from wheel 32 to the spaced rudders 45 where they are connected to the respective rudder horns 45a. 'A cable or wire 48 connects the two rudders to operatively couple them for swinging by

cables

46 and 41, as will be readily understood.

With the two control arrangement of Fig. 6, sufiicient control directionally and laterally is obtainable in cooperation with the other design features of the invention, if the Wing W is given suificient dihedral as here shown, for handling and maneuvering the airplane in the air, as well as in landing or taking off even in cross winds. As in the two-control system of Figs. 1 to 5, the arrangement of Fig. 6 eliminates the foot operated control and the necessity'of acquiring the technique and skill required for coordinating a foot and a manually operated control.

The two controls may, in accordance with the disclosures of Fig. 7, consist of the elevator |4 providing the pitch control, and a single control for changing the direction of flight that consists of the opposite ailerons or roll control surfaces R and the vertical rudders 45 connected with the ailerons R through the aileron operating mechanism or cables so as to be simultaneously operated with the ailerons. In the present example, the ailerons or roll control surfaces R of this single control for changing the direction of flight are of the more or less conventional trailing type mounted on the wing W at opposite sides of the longitudinal axis of the airplane and actuated by a control mechanism for differential operation in the more or less conventional manner.

Such an aileron operating mechanism may, for example, embody a horn or crank 50 fixed on and extending above and below each aileron R together with a cable 5| interconnecting the upper ends of the opposite aileron horns 50, the cable 5| being carried over and around suitable pulleys 5|a at opposite sides of the wing. A cable 52 is connected to the lower end of the horn 50 of the right-hand aileron R and this cable 52 extends over suitable pulleys 52a to the drum 32a of the control wheel 32 on the upper end of the control column 3|. A cable 53 is connected to the lower end of the horn 50 of the left-hand aileron R and extends. around suitable pulleys 53a to the drum 32a of the control wheel 32 on the upper end of the control column 3|. Thus, by turning control wheel 32 to the right or to the left, the opposite ailerons R are differentially displacedthrough the arrangement of control cables 5|, 52 and 53, in the usual manner to obtain roll control for theairplane.

The vertical rudders45 have the-hereinbefore described operating

cables

46 and 41 extended forwardly along the outrigger spars Ill and in the present form of two control system of the invention, these

rudder operating cables

46 and 41 are connected into and with the

control cables

52 and 53, respectively, of the right and left wing ailerons R. For instance, rudder operating cable 41 for the right-hand rudder 45 after passing over suitable pulleys is connected to the cable 53 from the left wing aileron R, while the cable 46 from the left rudder 45, after passing over. suitable pulleys is connected to the cable 52 from the right ring aileron R. Thus, the cables in the example hereof, form a means for connecting or coupling the rudders with the ailerons for simultaneous operation as a single control. If desired, any suitable detachable connecting means may be employed for

coupling cables

46 and 41 to the cables 52 and 5 3, respectively.

The

rudder operating cables

46 and 41 so connected into and with the

aileron operating cables

52 and 53 thus provide for simultaneous operation of the rudders and ailerons for roll and yaw to thereby provide a wing control for changing the direction of flight of the airplane. This single control is, through the

cables

52 and 53, operable from and by the steering or control wheel 32 of the pilot operated control unit which includes the control column 3|. Rotation of the control Wheel 32 to the right will lower the left wing aileron R and raise the right wing aileron R and simultaneously swing or displace the ver tical rudders 45 to the right, so that the direction of flight of the airplane will be changed to the right. When the control wheel 32 is rotated to the left, the reverse movements or displacements of the ailerons R and rudders 45 take place and the direction of flight of the airplane is changed toward the left.

. The foregoing arrangement disclosed by Fig. '7 of the drawings of two controls consisting of the control for pitch and the single control for roll and yaw comprising the combination of aileron or roll control surfaces and vertical rudders in combination with the directionally stable landing gear of the present invention as hereinbefore described and explained, enables complete control and maneuvering of the airplane for all normal conditions of take off, flight and landing, including the landing of the airplane with side drift, by the operation solely of such two controls.

In accordance with another feature of an airplane design of my invention, the airplane illustrated balances at a slightly lower angle of attack with the power on than with the power off. As the longitudinal control is limited to prevent sustained stalling with either power on or power off, the airplane will always climb if full power is applied with the airplane at speeds below the maximum level flight speed-In this manner, I have eliminatedthe possibility of the airplane losing altitude in straight flight at low speed with full power on. The general design of the illustrated example which provides the pusher propeller and a high line of thrust, contributes to balancing the airplane at a slightly lower angle of attack with power on than with power off, so that it becomes impossible to maintain a stalled attitude in either case.

' In connection with the landing characteristics and the ground handling of the airplane, my design provides the relation between the landing gear and wing of the airplane such that the angle of incidence of the wing is approximately 0 when the airplane is at rest on the ground. In landing, therefore, as soon as the ground is contacted, the wing angle of attack is immediately reduced to 0 so that wing lift is reduced to a negligible amount to prevent any tendency'of the airplane to float off the ground if landed above its minimum landing speed. This feature of the design also materially facilitates handling the airplane on the ground in high winds.

The invention provides a relation between the body B, the wing or lifting surface W and the rear wheels I5 and forward wheel 5 of the landing gear, such that with the airplane supported in normal position by said wheels on the ground, the body 13 is maintained in substantially horizontal attitude with its longitudinal axis approximately parallel to the ground. Thus, the airplane, when supported on the ground in normal position has the body 13 and the wing or lifting surface W in substantially normal cruising flight attitude with the occupants seats in their normal attitude for natural seated position. The invention further provides for the maintenance of this normal cruising flight attitude of the airplane during take off, that is, with the bodyv B in its substantially horizontal, position and the wing or lifting surface W at its normal cruising flight angle of incidence.

The relation of the wing or lifting surface W to the landing wheels and the body 13 in normal ground attitude of the airplane is such that the wing or lifting surface W has an angle of incidence, which, for the particular wing used in the present example, will give substantiallythe lift coefficient used in normal cruising flight. For

- instance, with the particular wing or lifting surface W of the examples hereof, the angle of incidence of the wing when the airplane is in normal position supported on the ground by the landing wheels, that is, is in normal cruising flight attitude, is approximately zero degrees Hence, in normal cruising flight attitude of 'the airplane, the wing also has such approximately zero degree (0") angle of incidence. Such an approximate zero degree (0) angle of incidence, where, as in the example hereof, the angle of incidence of the wing with the airplane in normal ground position is the same as the angle of incidence of the wing in normal cruising flight attitude of the airplane is such an angle as will give the wing a lift coeflicient of a certain percentage of the maximum lift coefficient for the wing. In the form of the wing W, having the auxiliary airfoil A, the wing, when at its approximately zero degree (0) angle of incidence, has a lift coeiiicient approximately or of the order of one-fifth (V) of the maximum lift 00- efiicient forsuch wing. 0n the other hand, the

wing W, without the auxiliary airfoil A, when at the approximately zero degree (0") angle of incidence, has a lift coeflicient approximately or' of the order of one-fourth to one-third (V of the maximum lift coemcient for such wing.

In terms of speed, such cruising angle of inci- I clenc range may be said to be such that in order for the wing to develop a sumcient lift to enable the airplane to take off, the airplane musttravel at a rate of speed of at least of the order of fifty per cent (50%) in excess of the minimum landing speed for the airplane.

When taking off withthe airplane having the landing wheels, body and lifting surface so relatively arranged, the normal horizontal attitude of the body B and the above-referred to angles of incidence for thewing or lifting surface W may be maintained. However, due to the aforesaid relatively low angles of incidence, a relatively long take off run is necessary in order for the airplane to attain a speed necessary for the wing at such angles of incidence to develop a lift suflicient to take off the airplane. Under certain ground conditions, and particularly muddy or sandy conditions, it is difficult, or, at times, even impossible, to attain a sumcient speed for the airplane to deairplane as such features may may, for example, as in the case of an amphibian,

have a high thrust line, it is practically impossible under the foregoing ground conditions to get the tail of the airplane down because in such case, the drag on the wheels gives a moment tending to press the nose of the airplane down. Thus, an increase in the angle of attack of the wing W by changing the attitude of the body B and the wing W in order to increase the lift during take off under such conditions can not be accomplished.

In accordance with a feature of my invention, means are provided in combination with the foregoing arrangement of the landing wheels, body and wing of the airplane, through the medium of which the lift of the wing W can be increased during take off without changing the normal cruising flight or ground supported attitude of the and its body B and wing W. For instance, as one example of such a wing lift varying means, I have provided a lift varying wing flap F on the wing W together with the pilotcontrolled mechanism for operating this flap that includes the control lever I! (see Fig. 3), as hereinbefore described. Thus, during the take off of the airplane, the lift of the wing W can be arbitrarily selectively increased by the pilot to thereby enable the airplane to take off with a minimum of ground run and without changing the normal horizontal attitude of the body B or the normal cruising flight angle of incidence of the main or fixed portion of the wing or lifting surface W. I

The various features therewith of the two-control system, be used to advantage with the conventional three-control system, and similarly the use of a conventional wing is not precluded in a design in which certain of the other features are incorporated, as such other features can still contribute advantages when embodied in a design of airplane having conventional wings. The directionally stable landing gear of my present invention isnot restricted to use with an airplane embodying any of the other features and characteristics of theinvention, but is of general use on airplanes of various other designs, including the conventional.

inclusion As a result of the principles, features and characterlstics of my invention, anairplane designed to embody and incorporate them has a high degree of safety and requires very little skill to fly and to land and take off. Due to the wide range of gliding angles for the pilot to select from, together with the characteristics of low minimum gliding speed, lateral stability and control throughout the full speed and angle of attack range, and the inability to remain in the stall, the airplane can be easily and accurately landed on a very small space guiding the airplane to the fleld and. letting it glide into contact with the ground. The combination with the foregoing characteristics of the directionally stable landing gear further simplifies and reduces the landing skill required and enables safe landings in cross winds. The necessity for but two controls made possible by thev above features of the design, still further reduces the skill required to operate the airplaneand makes learning to fly and operate the airplane a simple and rapid process. The operation of taking off is also of the invention are not, necessarily limited in a design of airplane to the and practically by merely disclosures hereof.

What I claim is:-

1. In aircraft, the combination of a body, a lifting surface, directionally fixed landing wheels to the rear of the center of gravity of the aircraft, a normally freely castering landing wheel forward of the aircraft center of gravity and adapted for cooperation with said directionally fixed landing wheels to provide a landing means for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing means when the aircraft is landing with side drift and means for controlling the aircraft in normal maneuvers in landing and flying comprising solely a pitch control and a control for changing the direction of flight.

2. In an airplane, in combination, a system of controls for the airplane consisting solely of a pitch control and a control for roll, and a landing and taxying gear for the airplane that is normally directionally stable when supporting the airplane on a landing surface with the airplane moving forward, said landing gear embodying directionally fixed landing surface engaging means mounted on the airplane to the rear of the airplane center of gravity, and normally freely castering landing surface engaging means mounted on the airplane forward of the airplane center of gravity and adapted for cooperation with said directionally fixed landing surface engaging means to provide a landing gear for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing gear when the airplane is landing with side drift.

3. In an aircraft, the combination of a body, a lifting surface, directionally fixed landing surface engaging means to the rear of the center of gravity of the aircraft, a normally freely castering landing surface engaging means forward of the aircraft center of gravity and adapted for cooperation with said directionally fixed landing surface engaging means for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing means when the aircraft is landing with side drift, and means for controlling the aircraft in normal maneuvers in landing and flying comprising solely a pitch control and a control for changing the direction of flight that includes a swingable vertical rudder surface.

4. In an aircraft,in combination, directionally fixed landing surface engaging means to the rear of the center of gravity of the aircraft, a normally freely castering landing surface engaging means forward of the aircraft center of gravity, and adapted for cooperation with said directionallyfixed landing surface engaging means for changing the aircraft heading to the direction of landing upon ground contact of said landing means .when the aircraft is landing with side drift, and means for controlling the aircraft in normal maneuvers inlanding and flying comprising solely a pitch control and one or more vertical rudder surfaces laterally swingable for changing the direction of flight.

5. In an aircraft, in combination, a body, a lifting surface, a directionally fixed landing surface engaging means to the rear of the center of gravity of the aircraft, a normally freely castering landing surface engaging means forward of the aircraft center of gravity and adapted for cooperation with said directionally fixed landing surface engaging means for changing the aircraft heading to the direction of landing upon ground contact of said landing means when the aircraft is landing with side drift, and means for controlling the aircraft in normal maneuvers in landing and flying comprising 'a pitch control embodying a horizontally disposed elevator surface vertically swingable about a horizontal axis, and a vertical rudder surface laterally swingable for changing the direction of flight, said vertical rudder surface being located to the rear of the aircraft center of gravity.

6. In an aircraft,in combination,a directionally fixed landing surface engaging means to the rear of the center of gravity of the aircraft, a normally freely castering landing surface engaging means forward of the aircraft center of gravity and adapted for cooperation with said directionally fixed landing surface engaging means for changing the aircraft heading to the direction of landing upon ground contact of saidlanding means when the aircraft is landing with side drift, and means for controlling the aircraft in normal maneuvers in landing and flying comprising a pitch control consisting of a horizontally disposed elevator surface vertically movable about a horizontal axis and a control for changing the direction of flight that includes lateral control surfaces at opposite sides of the longitudinal axis of the aircraft.

7. In an aircraft, a directionally fixed landing surface engaging means to the rear of the center of gravity of the aircraft, castering landing surface engaging means forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing surface engaging means to provide a landing means for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing means when the aircraft is landing with side drift, in combination with, an air control system for the aircraft consisting solely of a pitchcontrol and a single control only for both yawing and rolling control for the aircraft.

8. In an aircraft in combination, means for controlling the aircraft in normal maneuvers in landing and flying comprising solely a pitch control and a control for changing the direction of flight, a landing and taxying gear for the aircraft embodying directionally fixed landing wheels to the rear of the center of gravity of the aircraft, and a castering landing wheel forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing wheels for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing gear the aircraft is landing with side drift, and pilot actuated means operatively connected with said forward castering wheel for arbitrarily swinging said wheel for steering the aircraft on a landing surface.

9. In an aircraft in combination, means for controllingthe aircraft in normal maneuvers in landing and flying comprising solely a pitch control and a control for changing the direction of flight, a landing and taxying gear for the aircraft. embodying directionally fixed landing wheels to the rear of the center of gravity of the aircraft and a castering landing wheel forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing wheels for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing gear when the aircraft is landing with side drift, mechanism for. actuating said directionof flight control, and said castering landing wheel being operatively connected with said control actuating mechanism whereby operation of said mechanism to actuate the direction of flight control swings said forward castering wheel to steer the aircraft when on a landing surface.

10. In an aircraft, in combination, means for controlling the aircraft in normal maneuvers in landing and flying comprising solely a pitch control and a control for changing the direction of flight, a single manually actuated control operating unit for operating both the pitch and the direction of flight controls, directionally fixed landing wheels to the rear of the aircraft center of gravity, a castering landing wheel forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing wheels to provide a landing means for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing wheels when the aircraft is landing with side drift, and said castering landing wheel being operatively connected to said single control operating unit so that selective operation of said unit to actuate the directional control-swings said castering landing wheel for arbitrarily steering the aircraft on a landing surface.

11. In an aircraft, in combination, a system of air controls for the aircraft consisting solely of a pitch control and a single control only for both yawing and rolling control of the aircraft, a single manually operable control unit for operating both said pitch control and said single control for yaw and roll, a landing and taxying gear for the aircraft comprising directionally fixed landing wheels to the rear of the aircraft center of gravity and a castering landing wheel forward of the aircraft center of gravity, and means operatively connecting said forward castering landing wheel with the manually operable control unit whereby selective operation of the latter to actuate said single control for yaw and roll swings said castering wheel for arbitrarily steering the aircraft on a landing surface.

12. In an aircraft, a body, a lifting surface, a landing gear for the aircraft, embodying directionally fixed landing wheels to the rear of the air craft center of gravity and a landing wheel forward of the air craft center of gravity, said wheels being so mounted and arranged that with the air craft supported thereby in normal position on the ground, said body is in substantially horizontally disposed attitude with its longitudinal axis approximately parallel to the ground,

said lifting surface being so mounted relative to the body and to the landing wheels that with the aircraft in normal position supported on the ground the lifting surface has an angle of incidence of approximately zer-o degrees in combination with means for increasing the lift coefficient of said lifting surface when the aircraft is moving forwardly in normal position supported on the ground by said landing wheels without changing the normal horizontal attitude of said stantially horizontally disposed attitude with its longitudinal axis approximately parallel to the ground, said lifting surface being mounted relative to the body and to the landing wheels so that with the aircraft in normal position supported on the ground the lifting surface has an angle of incidence such that the lift coemcient for the lifting surface at such incidence angle does not exceed approximately one-third A,) of the maximum lift coeflicient for such lifting surface, means for increasing the lift coefficient of said lifting.

surface when the aircraft is moving forwardly in normal position supported on the ground by said landing wheels without changing the normal substantially horizontal attitude of said body or the aforesaid normal an-gleof incidence of said wing, and mechanism under the control of the pilot for arbitrarily selectively operating said lift lncreasing means.

14. In an aircraft, in combination, a body, a landing gear for the aircraft embodying landing wheels respectively spaced forward of and to the rear of the aircraft center of gravity, a lifting surface for the aircraft, said landing wheels being so mounted and arranged relative to said body and to said lifting surface that when the aircraft is supported by said wheels in normal position on the landing surface, said body is in substantially horizontally disposed normal cruising flight attitude and said lifting surface is at I an angle of incidence such that the lift coefficient for the lifting surface at such angle does not exceed approximately one-third of the maximum lift coemcient for such lifting surface, a flap member mounted on said lifting surface for movement to positions-increasing the lift coefilcient of said surface, and pilot actuated mechanism for moving said flap member whereby the lift coefficient of said lifting surface can be increased for the take off run of said aircraft to thereby enable the'aircraft to take off without changing the normal horizontal attitude of the aircraft body .or the normal angle of incidence of the main portion of said lifting surface.

15. In an aircraft, in combination, a body, a landing gear for the aircraft comprising directionally fixed landing wheels to the rear of the aircraft center of gravity, a normally freely castering landing wheel forward of the aircraft center of gravity adapted for cooperation with the said directionally fixed landing wheels for automatically changing the aircraft heading to the direction of landing upon ground contact of said directionally fixed and said castering landing wheels being 50 mounted and arranged relative to said body and to said lifting surface that when the aircraft is supported by said wheels in normal position on the ground, said body is in substantially horizontally disposed attitude and said lifting surface is at an angle of incidence such that it requires the aircraft to travel at a rate of speed of over approximatehpfifty per cent (50%) in excess of its minimum landing speed in order to take off, a flap member mounted on said lifting surface for movement from normal position to positions increasing the lift of said surface, and pilot actuated mechanism for selectively arbitrarily moving said flap member to a lift increasing position during the take off run of said aircraft without changing the normal horizontal attitude of the aircraft body or the normal angle of incidence of said lifting surface to thereby enable the aircraft to take off at a rate of travel less than that required for the lifting surface at such normal angle of incidence and with the flap in normal position.

16. In an aircraft, a body, a lifting surface, directionally fixed landing wheels to the rear of the center of gravity of the aircraft, a normally freely castering landing wheels forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing wheels for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing wheels when the aircraft is landing with side drift, in combination with, air controls comprising a control for pitch embodying an elevator surface vertically displaceable about a horizontal axis, a control for roll embodying control surfaces at opposite sides of the longitudinal axis of the aircraft, and a control for yaw embodying a laterally swingable vertical rudder surface, means for connecting the vertical rudder surface and said roll control surfaces together for simultaneous operation only, as a single combined yaw and roll control, and'a manually operable control unit operatively connected with said combined yaw and roll control, whereby the aircraft can be-landed with side drift solely by the operation of said pitch control and the said combined yaw and roll control.

17. In an aircraft, a body, a lifting surface, directionally fixed landing wheels to the rear of the aircraft center of gravity, a normally freely castering landing wheel forward of the aircraft center of gravity adapted for cooperation with said directionally fixed landing wheels for automatically changing the aircraft heading to the direction of landing upon ground contact of said landing wheels when the aircraft is landing with side drift, in combination with an air control system comprising solely a control for pitch and a control for changing the direction of flight, said direction of flight control embodying a laterally swingable vertical rudder surface and roll control surfaces at opposite sides of the longitudinal axis of the aircraft, means for connecting said vertical rudder surface and said roll control surfaces for simultaneous operation only, as a single control, and a single manually operated control unit connected with said pitch control and with said control for changing-the direction of flight whereby the aircraft can be landed with side drift solely by operation of said pitch control and said direction of flight control.

FRED E. WEICK.