US2222997A - Control means for airplanes - Google Patents

Description

No 25, 1940. G. M. BELLANCA Erm. .2.222,997

CONTROL: MEANS FOR AIRPLANES v Original Filed Sept. 2l, 1937 3 Sheets-Sheet l @htm/man Nov. 26,` 1940.

G. M. BELLANCA Erm. 2,222,997

- CONTROL MEANS FQR AIRPLANES original Filed sept. 21, 1957 s sheets-sheet 2 No 25,1940- G; M. BELLANCA ETAL 2,222,997

I CONTROL MEANS FOR AIRPLANES Original Filed Sept. 2l, 1937 5 Sheets-Sheet 3 o reactions of each'member on the other.

'Patented Nov. 2s, 1940 tusnifriezn STATE sv .PATENT OFFICE CONTROLMENS FR AIRPLANES Giuseppe M. 1lellanca and John Bellanoa,

ew Castle, Del. Application SleitemberZL'lilS'l, Serial'No. 164,950

newed-Aprll 16, 1940 6 Claims. (Cl. 244-90) ing edge of the wing for a considerable span, and

the short type mounted near the wingtip. Each l0 type has certain advantages which may recommend 4its use to any particularl design oi plane.

In recent years, considerable interest has developed in wing flaps. As is known, the trailing edge flap is a member which is connected to the I i6 rear portion of the wing and is adapted to be depressed or lowered so as, in eiiect, to markedly modify the camber of the main wing, thus increasing thel lift olsuch wing and, by concomitantly increasing the drag, very markedly i0 lower the critical take-oil and landing speeds.

Despite the real potentiaiities of thel flap, its full value had not been, and, in the nature ofv prior designs. could not be attained. The eilect achieved from mounting a nap on the wing, 25 in the very nature of its operation, depends on its size. The greatest enectiveness is achieved .by having the nap extend substantially the full span of the wing. In the typical designs of planes, however, this is impossible, since not an so inconsiderable portion of the available trailing edge of the wing must. be allocated to the aileron in orderl to insure proper lateral control. The

utilization Aof a nap and an aileron on the same` wing has the efore represented a none too satisas factory compromise between maximum potential fiap` and aileron' eiiiciency respectively. As those skilled in the art know, assembling a nap and aileron, on the wing in necessarily closely juxtaposed position, causes undesired air ilow Theres fore, in the past'full potential benefits of nap operation have not been secured.

We have found that the maximum advantages of the function of ailap may be secured and 45 that, furthermore, additional advantages, particularly in the attainment of low. landing and take-oi! speeds; may be secured by utilizing a flap and correlating this in a special manner with a novel type of lateral control means or aileron 50 construction. As will be seen more fully, the concept of the present invention :involves the utilization of any desired sectionv of the trailingedge of the wing, and up to the full span, forl .flap action,

u ployed area, namely, the wing tip and its lateral and utilizing a heretofore unemprojection as the zone of action of the aileron. In this manner, as will be appreciated, the ailerons are displaced from the naps and do not engender the undesirable airflow reactions that have obtained in the past. Furthermore, as 6 those skilled in the art will appreciate, utilization oi ailerons in the wing ti-p area presents at once the combined advantages of the long and .short nap. In order to enable a more ready comprehension l0 of the invention, a typical physical embodiment is shown in the accompanying drawings, 'of which:

Figure l is a plan view ofan airplane embody-v ing the invention. l l Figure 2 is a similar plan view, showing the ailerons in operative position. i Y

Figure 3 isa similar view, illustrating the con- Joint use of ailerons and naps for securing low landing and take-on speeds. .v 20 Figure 4 is a laterial cross-section of the main airfoil or sustenation surface. Y

Figure 5 is a cross-section taken on line l-'I ot Figure 4.

Figure 6 is a horizontal section taken on line 25 6--B`of Figure 4.

Figure 'I is-an enlarged detail of a portion of the aileron operating-me Figure 8 is a schematic view of'an illustrative aileron operating linkage.. 30

Figure 9 is a diagrammatic-illustration oi the mechanism for effecting simultaneous operation of the ailerons f As indicated, the improvements contemplated herein may be embodied in, a typical land or e5 v sea plane, for purposes of illustration the irn-` provements are shown as incorporated in a land plane. "Such plane may comprise a fuselage Vwhich is provided with airfoils I, empennage l, landing mechanism I, and a suitable power plant o for driving the propeller i. For simplicity, the invention will be described-.as embodied in a monoplane but it will, of course, be appreciated i that the improvements contemplated herein mayl be utilized inany type of multiplane.

V.is shown in the drawings. the naps s are .pivotally mounted adiacentthe trailing edge of the wings l, in any suitable manner such that, in retracted position, `they are substantially comprised withinthe contour of* the main air- 50 t foil, and are adapted -to be rotated downwardly,

by suitable mechanism, to the operative position. It is particularly to be observedthat such naps l may extend the full nxed span of the wing, thus permitting maximum nap etiect. In 5s the present mode of construction, as will be seen, the ailerons impose absolutely no limitations on the length of the cord of the aps, such maximum length being determined only by the span of the main wing itself.

In achieving lateral control, a new aileron principle is invoked. Briefly considered, this comprises the utilization of the laterally slidable or movable ailerons `1 and 8. The ailerons are adapted to bemoved either independently or simultaneously from a position nested within the main airfoil, laterally outwardly to anyr desired extended position.

With this type of operation, it will be appreciated that most eective lateral control is achieved. ,Such control is accomplished, in a sense, by providing main airfoils of optionally .variable span. Those skilled in the art will be quick to appreciate the mode of operation of such units. For example, referring to Figure 2,

assuming that it is desired to bank to the left,

suitable pilot control mechanism may be operated to cause the ailerons 1 to move from the position shown in Figure 1 to that shown in Figure 2. In these circumstances, the right wing then has a greater effective lifting surface and an increased lifting movement isV imposed on the right side of the plane. Since the aileron is effective at the outermost part of the wing, the maximum mechanical advantage of a long lever arm is secured.

It has been found that the lifting effect of an aileron on one wing may be advantageously correlated with means on the other wing to impose on such latter wing an increased drag, thereby imparting a desirable yawing moment to the For this purpose, as will be seen more -v plane. particularly from an inspection of Figures 1 and 2, the-leading spar 9 (and, if desired, the trailing spar I) are extended so that sections 9' and I0 project slightly beyond the tips of the fixed main airfoils. This projection or projections may comprise integral parts of the separate spars or may be separate members, attached to the spars and/or ribs. Preferably, they consist of at or non-streamlined prolongations or one or more of the spars; it will be understood, however, that, to secure the functions to be described, this is not essential, since any non-streamlined projection member may be employed. It will also be understood that the design of the projections 8 and I0 may be so conformed as to secure any desired degree of drag.

As will be seen, from an inspection of Figure 1, the -ailerons are so mounted that, for normal horizontal flight, each aileron projects a slight, equal distance beyond the wing tip, such distance being at least that which is necessary to cause the streamlined .ailerons to enclose the nonstreamlined, drag-inducing projections 9' and I0'. In these circumstances, that is to say, when the ailerons are in the position shown in Figure 1, the'plane is in lateral l dynamic balance.

When the ailerons are in the position shown in Figure 2, that is when aileron 'I is projected outwardly of the wing tip and the aileron 8 is simultaneously retracted with the airfoil, there is immediately and simultaneously imposed an increased lifting effect on the right wing and a markedly increased drag on the left. It is particularly to be observed that' this type of reaction is quite different from that obtaining in the ordinary aileron. In these latter circumstances, operation of the typical aileron on, say, the right wing, effects an increased lift, but such increased lift is accomplished by a corresponding increased of the aileron operating frame. 4 vself is provided with the slots 23 and 24 which,

drag. Since the aileron on the left side is not operated and istherefore Within the streamlines contour, the left Wing, i. e., the low drag wing, tends to move more rapidly than the right (high drag) wing. In the present, improved, construction, however, by invoking the concept of the utilization of members ('9' and/or I0') which positively insure a marked and predetermined drag, a novel and beneficial correlation of drag and lifting, on respectively opposite sides of the plane, is achieved.

It will be observed that the aps 6 are available for unrestricted operation during any of these periods when the ailerons l and 8 are in the diiferent positions described.

As has been indicated hereinbefore, this type of aileron control presents an opportunity for a special and particularly advantageous correlation with the flaps for the purpose of securing a lmarked diminution of the critical flying speed.

As shown in Figure 3, this type of construction enables the simultaneous operation of the iiaps to the high lift position with the full and simultaneous projection of the ailerons. Thus, assuming that it is desired to land at a minimum speed, the ailerons 1 and 8 may be simultaneously operated (in a manner more particularly to be described) lso as to be projected outwardly to their full extent. -In these circumstances, the plane is in lateral balance, but by using a markedly increased wing area the'lifting effect of each wing is equally increased, and to a marked degree.v

l are constructed of a size which is suitable forthe particular plane in which they are'used. The structural features of the aileron may, of course, vary in a manner known to skilled designers. Such ailerons may comprise, in eiect, diminutive airfoils. 4'I'hese ailerons are ruggedly constructed and are provided with a suitable'truss framework extension, designated generally by the numeral I l.` Such extension may comprise the beams or braces I2 and I3, constructed of suitable materials such as high strength'nonferrous alloys, and the like. To these may be connected a member I 4. This framework may y be rigidified and strengthened by .the strut members I5 and,|6. 'I'he members I2 and I 3,-as will be seen from an inspection of the drawings are utilized notonly as rigidifying structural elements for the aileron, but also as a means for guiding the ailerons in their lateral movement.

'.in a lateral plane at the option of the pilot. It

will be observed from an inspection of Figures 6 and 8 that the member I1 .is spaced from the adjacent member I2 and that similarly the member I3 is spaced from the adjacent member I2 'I'he aileron it- For this purpose, the. ailerons are provided with the spar members I1 The operating rods 22, as shown, are each pivoted y to a'long arm of the bell crank levers 30. Such bell crank levers4 are pivoted at 3i to yokes 32.

These yokes are formed with the end guiding j 34, which are adapted to nest or flanges 33 and fit within corresponding grooves in the fixed frames 35 ,for vertical movement therein. The

yokes 32 are internally threaded to receive the screw threaded members 35. These, as shown, project through the casings 35A and are provided with the bearings 31. Thel upper end of the shafts 35 are provided respectively with the beveled gears 38. One of the beveled gears' 38 meshes with a beveled gear 33, keyed or otherwise fixed to theoperating shaft member 40, which in turn is operated through suitable mechanism by the hand wheel or other'manuaily operable member 4|. A shaft 4,2, provided at each end with the bevel gears 43 and 44, extends'between vthe two screw shafts 35. With this type of linkage, it will be observed that the operation of the hand wheel 4I or other member will cause rotation of each of the threaded shafts 38 to effect simultaneous upward or downward movement of the two yokes 32', and correspondingly move the bell crank pivots 3i Fig. 9).

As noted above, the bell'crank levers are connected to yokes 32 which may constitute fixed or tated in a movable fulcra.' The short arm 50` of each bell crank lever is provided with a pin 5|, which fits in a slot in arm 52. The arm 52 is thus connected to each bell crank through a pin and slot or other equivalent overrunning connection. The arm 52 is keyed or otherwise rigidly connected to the rod 53, mounted for rotation in suitable bearings 54. The other end of this rod is connected to the typical stick 55. The stick is provided with a yoked rod 55 which is connectedfin the usual manner to the elevators in the empennage.

The operation of this structure will have been' 'appreciated from the foregoing description. When it is desired to bank the plane, the pilot moves the stick 55 laterally tothe left or right,

depending on the bank desired. Assuming that the stick 55 is moved to the left (Fig. 8), the

connecting rod 53 is then correspondingly rocounter-clockwise direction. Inthese circumstances, the' bell of Figure 8 is rotated in a clockwise direction and the bell crank at the right is rotated in a clockwise direction, as illustrated by the dash-lines A and B of Figure 9. Due to the` linkage, the aileron 5 is then extended and the aileron 1 is retracted. Movement oi the stick 55 in the opposite direction causes, of course, a reversal of these movements. Y

When it is desired to extendthe two ailerons simultaneously so as to secure the low landing speed desired, the member 4I is operated. In these circumstances, when the wheel 4i is operated, the yokes are simultaneously elevated and caused tov ride in their guideways $5. Since the inner ends of the short arms of the bell cranks are retained against vertical movement, such operation of the wheel 4| (as particularly illusv moves' counter-clockwise.

provide a guiding means for the slidable attached to the plates 12, upwardly and downwardly (see crank lever'30 at the left l edges 94 rectiy tothe aileron,

trated in Figure 9) causes the long arms of the two bell'crank levers to move outwardly as indicated by the dotted line position C and D. In

other words, the long arm of bell lever C moves clockwise, and the long arm of bell crank lever D The movement of each of these levers being, of course,.equal. During such movement, the pins 5i of the levers slide in their corresponding slots. In this manner, the wheel or crank 4i may be operated to move each aileron an equal distance outwardly of the wing tips. It will be noted also utilized to determine the normal horizontal flying position of each of the ailerons, 1 and 8. The mechanism shown in FigureV 8 and described herein, as will be appreciated, is merely illustrative of any similarly functioning structure.

In order to secure the operations hereinbefore described, the main airfoil is so 'constructed to ailerons. An example of a typical and suitable construction is shown in vFigures 4, 5 and 6. As shown in Fig'- ure 5, the main airfoil may be of any suitable type that the member 4i may v of construction, for example, provided with the "structure may be rigidiied by the rigidif'ying strut 63.

The internal structure of the aileron may be of any desired type and may comprise, as is shown in Figure 6, one or more' tubular spari members 10, and the associated ribs 1|. The ribs may be 13 and the like, so as to provide a gap or space 14, forming a guideway, whereby the aileron is guided in this lateral movement.

Y As shown, particularly in Figures 5 and 6, thc main spars 3i) and tension 30 (only one being shown) which-projects 8i are provided with an exan appreciable distance beyond the wing tip 8i,

This member 80 is preferably fiat'or honstreamlined and may be of a depth, and as here shown,

may be substantially equal to the camber of the aileron. While the aileron is shown with the gaps or open guideways 14, it will be understood that the guiding member or spar extension 80 may be somewhat shortened and a continuous canvas skin provided on the aileron.

.l The aileron is provided with a series of rollers 30 and 9i which are attached respectively vby means of the pivots 92 to the frame members i2 and i1. Preferably, such rollers are -offa low l and a lower edge guideway 35. The rollers. 90 and 9i are provided with the flange-bearing'. surto contact the guide y and 35 in the manner shown. The slot 33 is, as shown, elongated a sufficient distance to permit maximum outward and inward movement of the aileron.l anism is actuated in the manner heretofore described, the aileron may be moved outwardly faces which are adapted When the operating mech- Yfriction type and may comprise the ball-bearing as shown in Figure 7.' As,

and inwardly. For example, referring to Figure 5, as the rod 22 is pulled inwardly of the plane, the rollers 30 and 3| ride uponv the guideways 34 and 05. lSince the rollers are attached dithis latter is retracted inwardly of the plane. During this movement,

the wing spar projection 50 (or equivalent member) serves as a supplemental guiding means for the aileron. When the aileron is in the extended position, the wing spar extension 80 (or equivalent) serves as, in effect, a fixed spar for the aileron, imparting to this latter member the necessary structural rigidity.

On the other hand, when the aileron is in fully retracted position the at or non-streamlined member 80 projects outwardly of the tip of the aileronand, in the manner explained, serves to materially increase the drag of the wing. In the normal horizontal flying position, as will be appreciated, the ailerons are each retracted to the position where the edge of member 80 coincides with, or is` Within, thetip of the aileron.

While it is not shown, it will be understood that additional vertical rollers, or other antifriction means, may be interposed between the flanges I2 and I1 and the vertical webs 91 and 98 of the spar construction.

'Ihe mechanism described is of course given as merely one illustrative and operable' embodiment of the invention. Other specifically different methods of mounting the ailerons and effecting their lateral movement may be utilized.

It will be understood that the flaps 6 are provided with any suitable pilot controlled mechanism (not shown) whereby they may be operated at any stage in the flight of the plane. y

It will be appreciated that an airplane, constructed according to the principles of the present invention, presents many advantages and a high operative eiliciency. The novel aileron construction is most eifective, .since each aileron, in eifect, is operative on the end of a long lever,

thus insuring immediate lateral control with minimum aileron area. The allocation of the ailerons is so correlated with the position of the aps that full aerodynamic efficiency of each is assured, in that, with thislocation of the two units, there Yare no negative aerodynamic reactions of one upon another. Similarly, as noted, the alleron construction is such that it insures a liftinducing force on one side of the longitudinal axis, and a simultaneous drag-inducing force on the other, thus positively establishing an advantageous yaw. Likewise, the aileron construction is .such that, at the`option of the pilot, it

'may be employed to simultaneously increase the lift on each side of the plane. 'I'his function, v

coupled and correlated with the flap operation, insures a. marked diminution of the critical flying speed, thus establishing a low landing and take-off speed. All these advantages are secured with a structure which is as simple and practical as it lsefiective.

Therefore, while preferred modication of the invention has been described, it is to be understood that this is given merely to exemplify the principles involved, and not as dening the exclusive means by which the eifectuated.

We claim:

principles may be 1. An airplane wing comprising an airfoll and an aileron normaily nested largely within the contour of the airfoil and movable along the span thereof to an operative position beyond the alrfoil tip and a guide member for the aileron, of non-streamlined form, projecting laterally beyond the wing tip.

2. An airplane .comprising a fuselage, main airfoll attached to the fuselage at each side thereof, lift-inducing and` drag-inducing means on each wing, said drag-inducing means being nested within the said lift-inducing means, and means simultaneously to effect the operation of the lift-inducing means on one wing and the drag-inducing meanson the opposite wing.

3. An airplane comprising a fuselage, main Wings attached to the fuselage at each side thereof, an aileron mounted within each Wing near the wing tip, guide means for the aileron extending beyond the tip of the wing; means to simultaneously extend the aileron of the one wing to a position outwardly of the wing tip to impose a lifting movement on such wing, and to retract the other aileron within the body of its associated wing to expose the said guide means to thereby impose a predetermined drag on such wing.

4. In an airplane having a fuselage and a wing on each side thereof, an aileron mounted within each wing and movable along the span thereof, and drag-inducing members projecting beyond the wing tip and means to expose such members b y lateral movement of the aileron to optionally increase the drag of a wing.

5. In an airplane having a fuselage and a wing on each side thereof, ailerons mounted within each wing, such ailerons being adapted to slide along the span of the wing and outwardly of the wing tip; drag-inducing members attached to the Wing and projecting beyond the wing tip; means to simultaneouslyextend one aileron to increase the lift of its associated wing, and to retract the other aileron to a position to expose the said drag-inducing means to the air stream to thereby increase the drag on its associatedwing.

6. An airplane comprising a fuselage, main wings attached to the fuselage on each side there- Aof, pivotedtrailing edge flaps attached to the wings and extending substantially the full span, ailerons nested within each wing, such ailerons being adapted to slide along the span of the wing and outwardly along the wing tip; drag-inducing members attached to the wing and projecting beyond the wing tip; means to simultaneously extend one aileron to increase the lift of its associated wing, and to retract the other aileron to a position to expose the said drag-inducing means to the air stream to thereby increase the drag on its associated wing.

GIUSEPPE M. BELLANCA. JOHN BELLANCA.

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