Protective Nose Cover And In-flight Removal Means

Abstract

An expendable nose shield for use in a multistage missile arrangement when a second stage is encapsulated within a first stage and is launched from such location upon burnout of the first stage. It comprises an ogive-shaped shell formed of four petallike quadrants with their bases secured to the leading edge of the first stage and their tips held together by a common clip. Forward movement of the second stage releases the clip and the quadrants separate and break off in the slipstream. The shield may also house a stabilizing fin assembly including a sleeve through which the second stage passes and which becomes attached to the slightly enlarged tail portion of the second stage when the latter emerges.

Description

STATEMENT OF GOVERNMENT INTEREST

THE invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefore.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to protective nose devices for rocket-type vehicles and more particularly it relates to improved nose shields which protect a second stage adapted to be launched from a first or boost stage at very high altitudes.

2. Description of the Prior Art

Primary means for exploration of the upper atmosphere has been the use of meteorological probes or sounding rockets. the normal method of placing such devices at desired altitudes is to use a first stage booster motor which ejects a second stage probe at first stage burnout. A suitable construction for this purpose is shown in the inventor's U.S. Pat. No. 3,377,952 and that patent and the background material there shown are incorporated herein by reference. In many instances the probe has sensitive instruments which must be protected from extreme conditions that may be encountered during its flight to a high altitude.

While various protective devices have been proposed as coverings for sounding probes during the early stage of flight serious difficulties may arise at the moment when the protective covering is removed. Prior art methods of removing such coverings include explosive mounting bolts which upon a predetermined signal will detonate and fragment the segmented protective cover. While this method is generally successful it does create timing and ignition problems and the handling of explosive materials may present hazards. Another method of removing the cover has been the breaking up or fragmenting of the protective cover by a severe blow from the inner probe as it is expelled. However under some circumstances such action may deflect or otherwise adversely affect the flight characteristics of the probe.

SUMMARY OF THE INVENTION

THE present invention concerns a protective cover for a probe and comprises a series of shaped sections in mated relationship which when assembled have an ogive-shaped appearance. Each section is preferably held in position at the base by rivets engaging the booster, and at the nose by a cone-shaped clip. A tail fin assembly for the probe may be positioned within the assembled cover where it is picked up by the rear end of the probe upon probe launch and becomes an essential part thereof as it emerges from the booster. Each tail fin is preferably aligned with a joint between the cover sections. Upon probe firing, the nose of the probe knocks off the clip and frees the sections so that they are torn off by the slipstream.

STATEMENT OF THE OBJECTS OF INVENTION

IT is an object of the present invention to provide an improved sounding rocket protective cover which is simple in design, rugged in structure and reliable in operation.

Another object of the invention is to provide a protective cover for a sounding rocket which is nonhazardous to ground personnel.

Another object of the invention is to provide a protective cover for a sounding rocket which does not interfere with the functioning of said rocket.

A further object is to provide a protective cover for a sounding probe which obviates any timing and ignition problems at the moment of probe release from the booster.

Other objects, advantages, and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall perspective view of the forward end of a rocket incorporating the present invention.

FIG. 2 is an enlarged longitudinal sectional view taken along line 2--2 of FIG. 1.

FIG. 3 is a perspective view of the cone-shaped nose clip.

FIG. 4 is an enlarged cross-sectional view taken along a line substantially corresponding to line 4--4 of FIG. 2.

FIG. 5 is an enlarged cross-sectional view taken along line 5--5 of FIG. 2.

FIG. 6 is a diagrammatic view of two ogive quadrants illustrating the tongue-in-slot arrangement of joining abutting edges.

FIG. 7 is a perspective view showing the interior surface of one ogive quadrant.

FIG. 8 is an enlarged cross-sectional view taken along line 8--8 of FIG. 4.

FIG. 9 is a diagrammatic representation of the relative positions of the parts as they appear just after probe expulsion.

DESCRIPTION OF THE PREFERRED EMBODIMENT

REFERRING now to the drawings and particularly to FIGS. 1 and 2 wherein is illustrated a protective probe cover assembly 10 and an enclosed probe 12. The nose portion 14 of probe 12 is nestled within the cover 10 while a central payload section 16 is positioned within an elongate canister 18 which extends within the bore of a booster motor 20. An elongated slightly tapered booster extension 24 is located between the end of the booster motor 20 and the cover assembly 10. Canister 18 has a flange 25 at its forward end which is clamped to the rear of the booster extension 24 by bolts 29 thus holding the canister in fixed axial alignment within the elongated bore of the propellant.

After a predetermined period of time, usually at burnout of the booster motor 20, it is necessary to free the probe 12 from the confines of the protective cover assembly 10. The removal of the cover assembly should be accomplished with as little probe interference as is possible so that no damage or deflection is caused to the probe or to any of the sensitive instruments carried thereon.

As shown in FIGS. 4 and 5, the protective cover assembly 10 includes four or more elongated and shaped sections 26 joined at abutting edges in mated relationship by a tongue-in-slot arrangement, each section being so shaped as to give an ogive appearance to the overall assembly. The rear portion of each section 26 may be riveted to a sleeve 27 which telescopes within booster extension 24. It will be noted in FIG. 7 that each section 26 has a grooved internally built up forward area 23 that cooperates with like areas of adjacent sections to provide a nose opening 30 having a tapered bore 32 therein. This bore receives a correspondingly tapered axial stem 36 of a cone-shaped clip 34 designed to lock together the forward ends of sections 26. At spaced peripheral intervals, reinforced ridges 27 (FIG. 4) are provided along the interior edges of each section 26.

The cone-cone shaped clip 34 (FIG. 3) has a bottom recess or groove 50 extending around the stem 36. This groove receives an arcuate protrusion 52 (FIG. 2) formed at the forward tip of each section 26 in such a manner as to lock the assembled sections together and prevent separation. It is apparent that forward axial movement directed against the inner end of stem 36 will eject the cone-shaped clip 34 and free the ends 52 from their locked positions. If desired an impact actuated explosive device can be incorporated in the stem which will assist separation by explosively removing the clip while simultaneously separating the sections until they are removed by the slipstream.

As shown in FIG. 2 a fin engaging and retaining ring 38 may be located within the booster extension 24 and may be an integral part thereof if so desired. A probe fin assembly including a tubular sleeve 42 and fins 44 may be engaged by ring 38 which serves to support and align the assembly as shown. Each fin 44 is accommodated within radially disposed slots 46 preferably positioned in registry with the joints of the assembled sections 26. The support sleeve 42 is slightly larger than the exterior dimension of the probe 12 so that when the probe leaves the booster motor 20 it will pass freely through the sleeve until the flared tail portion of the probe reaches the sleeve at which time the sleeve is picked up and carried along on the probe tail portion and the fins then serve to provide stability to the probe. O-ring 40 and a suitable snap ring 48 may be located within the stabilizer fin mounting unit 38 and serve to steady the fins 44 in place until they are picked up by the probe 12 as it leaves the booster.

Thus in operation it is clear that as the probe 10 leaves the booster motor 12 at burnout, the nose 14 thereof strikes clip 34 removing it and freeing the sections 26. As the probe emerges from the booster motor 12 the exterior surface of the probe nose pushes against the interior of the sections 26 moving them out to where the slip stream of the probe rips them away from their riveted base connection.

Claims

I claim:

1. A removable protective cover for sounding probes mounted at the nose of a booster motor comprising:

a series of shaped sections in mated relationship surrounding the probe, said sections connected at their base to the booster and forming a bore at the nose, and

a nose clip inserted in said bore which locks the sections in their mated relationship,

said sections and said nose clip having interfitting parts to retain the sections in place until clip removal, each of the sections having a forwardly projecting tongue at the leading edge thereof,

said nose clip including a circumferential groove into which the tongues on said sections are received, said nose clip also including an elongate control stem portion receivable in said bore and extending therethrough with the inner end of said stem lying in coaxial alignment with the forward end of the probe and directly in its path of forward movement,

thus upon launch from the booster, the probe strikes and removes the nose clip freeing the sections and wedging them outwards where they are torn loose from the booster by the slipstream.

2. The cover as defined in claim 1 wherein the sections are mated to each other by a tongue-in-slot arrangement.

3. The ogive-shaped cover as defined in claim 2 wherein the sections are connected to the booster motor by a series of breakaway fasteners.

4. The cover as defined in claim 1 wherein the sections are at least four in number.

5. The cover as defined in claim 4 wherein spaced reinforced areas occur on the interior surface of the joined sections to reinforce the joint area between adjacent sections.