July 11, 1950 w. r. custer 2,514,478 CHANNEL AIRPLANE Filed Aug. 14, 1947

INVENTOR, W. R. CUsTar BY 40%tree(2. attorneys Patented July 11, 1950 2,514,478

UNITED STATES PATENT OFFICE 2,514,478. CHANNEL WING ARPLANE Willard R. Custer, Hagerstown, Md. Application August 14, 1947, Serial No. 768,579. 3 Claims. (Cl: 244-12) 2 This invention relates to a channel Wing air formed into a channel 4. It will be noted from plane and represents improvements over that the drawings that the channel 4 is, semi-cylin shown and described in my copending applica drical in shape, has its axis, in the...direction of tion Serial Number 617,616, filed Sept. 20, 1945, flight, opens upwardly and at both ends. The and which matured as Pat. No. 2,476,482. chord of the channelis, substantially equal to one As a result of publication given tests of the half its diameter and roughly equal to one-half Custer, channel wing by private and government the fore-and-aft chord of the entire wing. As ill laboratories, the phenomenal, static lift of the lustrated to advantage in Figure 3, the channel in channel-type wing is now coming to be recog cross, section has an airfoil shape to provide lift nized in the art. Since I have described the ad 10 when the airplane is in flight. vantages and characteristics of the channel Wing A portion 2) of the wing, immediately forward in a number of previously-filed applications, it of the channel, is of airfoil shape in cross section is not necessary to reiterate them here. As a to prevent the front portion of the wing from result of many calculations and tests, I have in stalling at very low speeds. This results in vented certain improved ways of utilizing chan 5 greater lift and better control at landing speeds. nels in as taught by this application. The wing portion 20 will not interfere with the The principal object of this invention is to lifting effect of channel 4 so long as the chan provide a channel wing airplane having charac nel length is no greater than one-half the chan teristics of great static lift, as well as increased nel diameter. lift in flight. 20 An engine 2 mounted in each Wing portion It is another object to provide a channel wing 20 drives a 22 through the medium of airplane which resists stalling, even at remark shaft 23 rotating in journal 24 supported by ably low speeds. brace 25. Each propeller 22 rotates in close It is a further object to provide an airplane proximity to the aft edge is of channels 4. In that may be easily controlled at low landing and 25 the preferred embodiment shown, the length of take-off speeds. the propeller 22 is equal to the diameter of the These and other objects of the invention will channel 4, the channel extending below the be apparent to those skilled in the art from the wing and the axis of the propeller being in the following specification taken with the appended plane of the Wing. A fin 6 extends upwardly drawings wherein: 30 from the junction of the outboard edge of the Figure 1 is a top plan view of a two-engine channel 4 and the wing 3 to aerodynamically airplane constructed according to the teaching isolate the top surface of the Wing from the chan of this invention; nel. The optimum height for the fin has been Figure 2 is a front elevation view of the same; found to be about one-sixth of the diameter of Figure 3 is a transverse sectional view taken 35 the channel. The portion of the im through one of the on the line 3-3 of mediately adjacent the channel serves to provide Figure 1 looking in the direction of the arrows; a baffle for the in oard side of the channel, and, Figure 4 is a top plan view of a modified form like fin 6, prevents the spilling of air into the of the airplane wherein a single engine is em channel. ployed; 40 Referring now to Figures 4, 5 and 6, I show the Figure 5 is a fragmentary longitudinal Sec invention applied to a single-engine airplane hav tional view through the fuselage on the line 5-5 ing fuselage 39, Wings 33, and single channel 34. of Figure 4 looking in the direction of the air A motor 4 in fuselage 3 drives propeller 42 by rows; and means of shaft 43. Fins 46 extend upwardly Figure 6 is a detail fragmentary sectional view 45 from the junction of the edges of channel 34 and taken on the line 6-6 of Figure 4, showing to the Wings 33 a distance preferably equal to one advantage the wing channel, fuselage and pro Sixth of the diameter of the channel. The fins peller, the fuselage and propeller being shown 46 are extended rearwardly to provide a support in side elevation. for tail structure 3:. The portion 5e of the wing Referring now in greater detail to Figures 1, 50 forward of the channel 33 is in the shape of an 2, and 3, wherein I show one embodiment of the airfoil to provide lift in flight. In other respects invention, the airplane consists of fuselage fo, the modification of the invention shown in Fig tail structure f, 2, and wings 3. ures 4, 5 and 6, is similar to the previously de Each wing 3 is of substantially conventional scribed embodiment shown in Figures 1, 2 and 3. design except that an aft portion of the wing is 55 In the operation of the invention, the propeller,

2,514,478 3 4. rotating in close proximity to the aft edge of the 3. An aircraft comprising a fuselage, a wing channel, creates a vacuum in the channel, there member extending laterally therefrom, said wing by producing a great static lift. Experimenta member being formed with a recess extending tion has shown that the optimum length of a rearwardly from an intermediate part of the channel is equal to one-half the diameter of the wing to the aft edge of the latter, a channel mem channel. By constructing the channel Wing ac ber secured to and extending downwardly from cording to the teaching of this invention, it is Said Wing member and coextensive with said feasible to use shorter propellers than Would receSS, Said channel member forming a forwardly, otherwise be necessary and at the same time pro upWardly and rearwardly open channel, and a vide anti-stall characteristics to allow very slow 0. propeller mounted on said wing member at the landing speeds. The anti-stall feature combined aft edge of Said recess, said propeller being so dis with the inherently high static lift of the channel posed that the propeller disc extends above and contributes toward achieving that most desirable below the Wing member and the lower portion of goal of aircraft design: low landing speed and the periphery of the propeller disc substantially low take-off speed without mitigating cruising 5 coincides with the aft edge of the channel mem Speed. ber, whereby when the propeller rotates, it will While I have shown and described two forms of effect the flow of air rearwardly through said any invention, it is to be understood that I am not channel and above and below said wing member. to be limited thereto and that many changes WARD R. CUSTER, could be made without departing from the scope 20 of the claims hereto appended. REFERENCES CITED What I claim is: The following references are of record in the 1. A Wing for airplanes comprising a wing file of this patent: member formed with a recess extending rear wardly from an intermediate part of the wing to 25 UNITED STATES PATENTs the aft edge of the latter, and a channel member Number Name Date Secured to and extending downwardly from Said D. 115,854. Loudy ------July 25, 1939 Wing member and coextensive with said recess, 883,565 Fars ------Mar. 31, 1908 Said channel member forming a forwardly, up 979,341. Sargeant ------Dec. 20, 1910 Wardly and rearwardly open channel. 1220,512 Matta ------Oct. 10, 1916 2. A wing for airplanes, as recited in claim i, in 1913,809 Lanier ------June 3, 1933 conjunction with baffles carried by the top of the 2,194,596 Henter ------Mar. 26, 1940 Wing member above the sides of the channel.