Sept. 19, 1939. E. F. ZAPARKA 2,173,674 AILERON DEVICE Original Filled June 7, 1933 3 Sheets-Sheet l S NS vue tot in Awea/Z2-7erta so wao As ae as so as /7aeow/2waza oA 1774 car sis rtist it v Sept. 19, 1939. E. F. ZAPARKA 2,173,674 AILERON DEVICE Original Filled June 7, l933 3. Sheets-Sheet 2 M 74.12. M2 -or 2 T-277t a 27 Awaa(7 / 27aaeia sy e/r. 7-8%. detotivo 40 Sept. 19, 1939. E. F. ZAPARKA 2,173,674 ALERON DEWICE Original Filled June 7, l933 3 Sheets-Sheet 3 rvuertot Awezázzaze/7 "24-c. 4c. dittozvot y Patented Sept. 19, 1939 2,173,674 UNITED STATES PATENT OFFICE 2,173,674 AERON DEVICE Edward F. Zaparka, Baltimore, Md., assignor to Zap Development Corporation, Baltimore, Md., a. corporation of Delaware Application June 7, 1933, Serial No. 674,729 Renewed January 13, 1937 Claims. (C, 244-90) My invention relates to ailerons, and more wing equipped with the form of aileron shown particularly to ailerons which are balanced so in Figure 1; that it requires gradually increasing control stick Fig. 3 is a graph showing the control stick forces to move them from the neutral position. forces plotted with respect to the angle of at 5 Though I am not to be limited to any par tack of a combined pair of ailerons; 5. ticular location of the ailerons, the ailerons I Fig. 4 is a view in side elevation of an air have shown are of the type illustrated and de plane wing showing another form of my aileron; scribed in my application Serial No. 653,918, filed Fig. 5 is a detail view partly in section show January 27, 1933. ing the form of aileron illustrated in Figure 4, 10 The present application deals with the construc the different positions of the aileron being indi- 10 tion of the aileron per se, and the location of cated by dotted lines; the aileron as specified in Serial No. 653,918 is Fig. 6 is a detail view in side elevation and not restrictive in considering claims in this ap partly in section showing another form of ai plication, except as the language imposes such leron, the different positions being indicated in 15 limitations. dotted lines; Heretofore when a pair of ailerons moved in Fig. 7 is a detail view in side elevation and opposite directions from the neutral position, partly in section showing another form of aileron, there was a "soupy' action at the control stick the different positions being indicated in dotted for the first few degrees of movement of the pair lines; 20 of Zap ailerons from the neutral position. This Fig. 8 is a detail view in side elevation and 20 Soupy action was followed by a very sharp in partly in section showing another form of aileron, Crease in the stick forces necessary to move the the different positions being indicated in dotted pair of Zap ailerons when the change from the lines; vertical angle became great. Fig. 9 is a detail view in side elevation and 25. It is one of the objects of this invention to pro partly in section showing another form of aileron, 25 vide ailerons such that the forces necessary to the different positions being indicated in dotted move the pair of Zap ailerons through increas lines; ing plus and minus angles of attack is consider Fig. 10 is a side elevation of another modifica ably less than for a pair of normal Zap ailerons. tion of my aileron, the different positions being 30. It is a further object of this invention to pro indicated in dotted lines; 30 vide ailerons in which the center of pressure shift Fig. 11 is a rear elevational view of a wing at varying angles of attack creates favorable showing a different form of my aileron in posi hinge moments. - tion above the Wing; A still further object of my invention is to Fig. 12 is a detail view in side elevation of the . 35 provide aileron constructions which are so piv aileron illustrated in Figure 11. 35 oted that the pivot shifts with the angular move Referring to the drawings, in Figures 1 and 2 ment of the .aileron so that the shift in center of I have shown a form of my aileron having a pressure is compensated largely by varying the front slot construction. In Figure 1 I have shown moment arm between the center of pressure and an aileron having a fuselage , a motor 2, pro 40 the point of pivoting. w peller 3 and wings 4. Above the wings 4 and 40 Still another object of my invention is to pro near the trailing edge thereof, as shown in the vide ailerons so constructed that the tendency drawings, I have mounted ailerons 5. The ailerons for the center of pressure to shift on any one 5 are mounted on horns 6; the ailerons being piv designed area of an aileron in one direction is oted at T on the horns 6. The ailerons have 45 compensated for by shift of center of pressure in attached to their upper surface horns 8 to which 45 the opposite direction on another designed area, are pivoted at 9 the aileron control rods O. Em whereby there is a tendency for these opposite pennage surfaces are indicated at 4. shifts in center of pressure on the different de The aileron control rods 0 are pivoted at , 50 signed areas to at least in part neutralize each as diagrammatically illustrated in Figure 1, to a other. control member 2, which is pivoted at 3. The 50 In the drawings: control member 2 is provided with two arms 4 and 5, indicated in dotted lines. The arms 4. Figure 1 is a top plan view of an airplane are connected by a cable 6 and the arms 5 are equipped with one form of my aileron; connected by a cable 7. The cable passes 55 Fig. 2 is a detail view inside elevation of a over pulleys 8 and is attached to a control stick 55. 2,178,674 2 obtained, i.e. stick forces are such that the pilot 9. The aileron control mechanism is of the can control the plane easily; well known type and the details of construction (3) Additionally an increased rolling moment are not given herein. r Spaced from the upper front edge of the aileron is obtained due to the increased lift of the posi 5 is an element 20 which has a curved front sur tive aileron, which is in some instances in the face and is so shaped at its rear as to provide nature of 20 per cent increase in lift of positive a Substantially parallel slot 2 which slopes back aileron, and, therefore, a 10 per cent increase in total rolling moment. - Wardly and upwardly above the upper leading In Figs. 4 and 5 I have shown the aileron 5 pro edge of the aileron 5. The element 20 is sup vided with a supplemental airfoil 23, pivoted at O 10 ported in its spaced relationship to the upper 24 to the trailing edge of the aileron 5. The leading edge of the aileron 5 by means of support supplemental airfoil 23 is provided with a horn elements 22, only one of which is shown. 25 to which is pivoted at 26 a link 27 whose other Referring to Fig. 3, I have shown a graph in end is pivoted at 28 to the supporting horn 6 which the control stick forces in pounds necessary for the aileron 5. 15 5 to accomplish a certain movement of a pair of In Fig. 5 the interior construction of the aileron Zap ailerons in minus or plus directions from the 5 is shown, which is similar to the forms shown neutral position are indicated. The dotted line in Figs. 1 to 8, namely a construction in which . indicates the action of a pair of Zap ailerons there is a front hollow bracing tube 29 having placed as shown in Fig. 2, but without the slot supports 3 pivoted at 7 on the upper tip of the 20 S20 ted front construction just described. The un horn 6. There are provided slots 33 to permit the broken line on the graph indicates the stick forces horns 6 to pass into the interior of the aileron plotted with respect to a pair of Zap ailerons with 5. The position of the aileron 5 with respect leading edge fixed slots. Both lines approxi to the flap or supplemental airfoil 23 in varying mate actual performance. positions is shown in dotted lines in Fig. 5. 25 From an inspection of the dotted line in Fig. 3, Here the supplemental airfoil or flap 23 and it will be seen that for the first few degrees of the linkage indicated causes a phenomenon simi movement of the pair of ailerons from their neu lar to that in the form of aileron shown in Fig. 2, tral position the feel on the control stick is what namely a reduction in the hinge moment of the is known to pilots as “soupy'. The forces neces pair at high plus and minus angles of attack. 30 30 Sary to move the pair of ailerons then become Moreover, the flap increases the rolling moment Sharply greater, and at about ten degrees in the of the pair due to the down aileron. particular graph shown, the force to move an In the form of aileron shown in Fig.