US1501601A - Tail skid - Google Patents

Description

July 1 1924. 1,501,601

E. H. HERBIG TAIL SKID Filed June 9, 1922 2 Shunt-Shoot l s mummmunnumum- ITLVBIflIE-II'.

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W M z 'f July 15 1924. 1,501,601

E. H. HERBIG TAIL SKID Filed June 9, 1922 2 Shoots-Shoat 2 /0 2': arm (1:; as

Wan-3S3 Invlarflar and Patented July 15, 1924.

UNITED STATES PATENT OFFICE.

ELWO'OD H. HEBIBIG, OF DAYTON, OHIO, ASSIGNOR TO DAYTON-WRIGHT COMPANY, OF DAYTON, OHIO, A CORPORATION OF DELAWARE.

TAIL SKID.

Application filed June 9, 1922. Serial No. 567,035.

To all whom it may concern:

Be it known that I, Enwoon H. HERBIG, a citizen of the United States of America, residin at Dayton, county of Montgomery,

tate of Ohio, have invented certain new and useful Improvements in Tail Skids, of which the following is a full, clear, and exact description.

This invention relates to tail skids for airplanes or to any ground skid attached to a vehicle for a purpose similar to that of the airplane tail skid.

This invention is characterized especially by compactness, great strength, light weight, and simplicity of construction, the number of parts being reduced to a minimum, and the forces bemg carried to the supporting body or fuselage directly in all cases.

An especial object of this invention is to provide a simple stop means for preventing a dangerous de ection of the skid under excessive load or in case of a failure of the yield able restraining means, and also the restraining means may be put under an initial load and thus hold the skid firmly in its normal .position when not under load.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred forms of embodiments of the present invention are clearly shown.

In the drawings:

Fig. 1 is a plan view of an airplane tail skid and associated parts of a Welded tube fuselage.

Fig. 2 is a side elevation thereof, and shows in dotted lines the position of the upper end of he skid at extreme deflection.

Fig. 3 is a rear elevation of the tail skid parts taken on line 33 of Fig.2

In the drawings, like characters of reference designate like or corresponding parts. Numeral 1O designates the two upper longrons and 11 the two lower longrons, 12 an upper horizontal strut, 13 a lower horizontal strut, and 14 side struts of a bulk head designated in its entirety by numeral 15, of the welded tube fuselage in connection with which my invention has been shown. The upper horizontal strut 12 of the bulk head 15 is further braced by the strut 16 which extends from the center of strut 12 to the rear tip of the fuselage where the longrons 10 are secured to the tail post 18, and the lower horizontalstrut 13 is similarly braced by the strut 17.

The bulk head 15 is provided with an upper bearing 20 at the point of intersection of struts 12 and 16 and a lower bearing 21 at the intersection of struts 13 and 17 for rotatably mounting the vertical tube 25 therein. The skid 26 is pivoted on a horizontal pivot pin 27 tothe lower projecting end of tube 25. The fitting 28 for the pin 27 is preferably fastened to, the tube 25 by being provided with a shank which extends a suitable distance within tube 25 and is held therein by any suitable means, as by brazing. The fitting 30 is secured to the skid 26 in any suitable manner as by means of bolts, screws, or pins, and is made strong enou h to take the entire upward load on the sk1d shoe 31 when the skid contacts with the ground in landing. This upward load. is transmitted through the vertical tube 25 to the thrust bearing 20, the thrust being delivered by the bronze collar 32, which is secured to the tube 25 preferably by means of pins 33. The horizontal strut 12 is braced-to withstand this upward thrust by the tie rods or wires 35 which run diagonally downward to the lower longrons 11. (See Fig. 3.) An advantage is obtained by this arrangement of carrying the thrust first to thetop part of the fuselage frame and then transmitting it down to the lower longrons by tie braces, since these tie braces are in tension instead of compression, as would be the case if braces were used to carry the thrust from the lower part of the frame to the top longrons.

The bulk head 15 is preferably further braced along the sides and top and bottom of the fuselage by the usual diagonal ' brace wires 36 and 37, as illustrated in the drawings.

The upper end of skid 26 is guided by aguide rod 40 when the skid pivots upon the pin 27. This rod 40 is pivoted at 41 upon the collar 32 and passes through a slot 43 in the upper end '.of skid 26, this slot 43 being of somewhat greater depth than the diameter of the rod 40 to permit an angular movement of the rod therein, as shown in dotted lines in Fig. 2. Rigidly secured upon rod 40 are the two stops 44 and 45 which determines the limiting positions of skid 26 when under no load and when at maximum deflection respectively. The upper end of skid 26 is held yieldably against stop 44 by the shock absorber cord 50 WhlOl'i' is attached to the collar 32 by means of the shackle. 46 pivoted to the collar by pin 47. Preferably the shock absorber cord 50 is attached to the shackle 46 and to the skid 26 by being looped over small sheaves 48 which are rotatably mounted in shackle 46 and in a fitting 49 attached to the upper end of skid 26. Now it is clear that when skid 26 contacts with the ground in landing, theshock absorber cord 50 is stretched to allow the skid to pivot on pin 27 and the upper end of the skid will move downwardly toward the dotted position shown in Fig. 2, the rod 40 and the shackle 46 pivoting on pins 41 and 47 respectively to cause these parts to be in direct tension at all times. if the force on the skid shoe 31 is excessive or if the cord 50 or its connections should break, the stop 45 on rod 40 will limit the movement of the skid and prevent either end of the skid from doing damage to the fuselage structure, and will also prevent the tail of the fuselage from dropping down in dangerous proximity to the ground. In other words, stop 45 will so act as to render, an emergency skid, which is sometimes employed, unnecessary.

In case of a side motion of the tail in landing or taxiing, the entire structure of skid 26, tube 25, collar 32, rod 40 and cord 50 may rotate within the vertical. bearings 20 and 21., and. this rotation may occur entirely independently of the pivoting of skid 26 on pin 27. Thus the universal mounting of the skid will automatically accommodate any motion to which the skid will be subjected.

As an aid in guiding the plane when running over the ground means are provided for interconnecting the vertical rudder with the tail skid 26 so that they both cooperate to cause the plane to turn in the desired direction. The rocker arms 60 are rigidly se-- cured to the vertical tube 25, preferably by means of being welded to a collar 61 which in turn is pinned to tube 25 by means of pins 29 as shown. This collar 61 also acts to prevent tube 25 from dropping down through bearing 21 due to the weight of the skid 26 and its associated parts during flight. The cables 65 are attached to the ends of arms 60 by suitable means and are interconnected with the corresponding cables (not shown) which operate the vertical. tail rudd. This interconnection may be made either by running cables 65 all the way to mentor the foot rudder bar commonly used to op erate the rudder or by connecting cables 65 to the cables (not shown) leading from the rudder operatlng means back to the rudder masts. The tension springs 66 are preferably inserted in cables 65 in order to relieve the operator of violent jerks and vibrations which would be transmitted to the operatin means when the tail skid 26 runs over roug ground.

While the forms of mechanisms herein shown and described, constitute preferred forms of embodiments of the present invention, it is to be understood that other forms might be adopted, all coming within the S00 e of the claims which follow.

l hat I claim is as follows:

1. A tail skid for airplanes including a skid bar having universal pivot connection to the body of the airplane to permit the skid to swing in any direction, and a single stop means engaging the skid above its pivot to limit both the up and down movement of the skid.

2. A tail skid for airplanes including a skid bar having universal pivot connection to the body of the airplane to permit the skid to swing in any direction, and stop means engaging the skid above its pivot to limit both the up and down movement of the skid, said stop means bein supported from the airplane body at a point substantially vertical above the skid bar pivot.

3. A. tail skid for airplanes including a skid bar mounted upon its support so that it will pivot about both a vertical and hori-- zontal axis, and stop means engaging the upper part of the skid for limiting the upward movement of the skid about the horizontal axis at all times, said stop means being mounted upon the airplane to swing with the skid bar whenever said bar pivots on its vertical axis.

4. In combination with an airplane, a. ground skid having universal mounting upon said airplane, and a stop means for said skid having universal mounting attachment to said airplane.

5. In combination. with an. airplane, a. ground skid having universal mounting upon said airplane, and a stop means for said skid having universal mounting attachment to said airplane, said stop means engaging the upper part of said skid.

6. In combination, a rigid body, a ground skid having universal mounting upon said body, said skid being yieldably held in normal position when not under load, and I. single stop means engaging said skid to prevent excessive deflection. thereof in two directions.

7. In combination, a rigid body, a. ground skid having universal mounting u on said body, said. skid being yieldably hel in normal position when not under load, and stop means engaging said skid to prevent exces In testimonywhereof I hereto aflix my sive deflection thereof in two directions, said signature.

stop means including a rigid member pivotally mounted upon said body and guided by ELWOOD HERBIG' 5 the upper portion of said skid, and stop Witnesses:

means on said member for engaging said Gno. E. PASOO,

skid. Wu. P. P4500.

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