FR2559256A1 - MISSILE PROVIDED WITH A STYLING PLACED AT THE REAR END OF ITS FUSELAGE - Google Patents

Abstract

A MISSILE, WHICH NORMALLY CONTAINS A EMPENNAGE WITH THREE OR FOUR STABILIZING FLAPS DEPLOYING LATERAL, ACCORDING TO THE INVENTION ONLY A MAXIMUM OF TWO FLAPS 13, 14. AT DRIVE 11 IS PRINTED AT THE SAME TIME AS FUSELAGE 10 OR SEPARATELY THERE IS A ROTATIONAL MOVEMENT SO THAT THE SENSE OF INSTABILITY CHANGES CONSTANTLY, THE ROTATION FREQUENCY BEING SIGNIFICANTLY HIGHER THAN TANGUAGE OR LACET FREQUENCIES DUE TO INERTIA AND CAUSED BY DISSYMMETRY. IN THIS WAY WE CAN REMOVE TENSION STABILIZING FLAPS.

Description

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  MISSILE PROVIDED WITH A WINDOW PLACED AT THE REAR END OF

ITS FUSELAGE.

  The invention relates to a missile provided with a

  tail which is placed at the rear end of its fuselage

  lage and which comprises stabilizing flaps deploying laterally during the flight and rotating around the fuselage axis at the same time as the latter or relative thereto. Guide and unguided missile empennages have at least three, preferably four, but often also more than four stabilizing flaps deploying laterally. The stabilizing flaps are regularly distributed at the rear of the missile and arranged at equal angular distances from each other so that the stabilizing effect of the tail varies as little as

  possible with the angular position of the missile. To com-

  think about the asymmetries which can for example be provo-

  quées by an irregular distribution of the thrust of the thruster or by an irregular distribution. of the masses of the missile, it is known to make it turn around its longitudinal axis during the flight. This rotation is obtained by slightly obliquely placing the stabilizing flaps deployed laterally so that the air sweeping them rotates the tail and with it the entire missile. To compensate for these asymmetries, it generally suffices from 2 to 3 t / s. The maximum speed of rotation is sometimes also chosen higher, for example 16 t / s since it is inter alia necessary to guarantee a sufficient rotation over the whole range of speeds of a rocket. Finally, it is known to mount the empennage on the fuselage of the missile so that it can rotate around the longitudinal axis, the fuselage rotating by

compared to the tail.

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  The establishment of several stabilizing

  The missile tends to increase production and assembly costs. Due to the strict requirements imposed with regard to strength, aerodynamic shaping, compliance with dimensions and the like, the stabilizing flaps cannot be manufactured in the form of

  inexpensive serial products. On the contrary, their manufacture

  cation is complicated and expensive due to the high

required quality.

  The object of the invention is to develop a

  missile of the aforementioned type whose manufacturing costs can-

  feels to be reduced without reducing performance

missile.

  This result is achieved according to the invention by the fact that a maximum of two stabilizing flaps are provided and that the speed of rotation is substantially greater than the frequencies of pitch or yaw due to inertia.

  and caused by the asymmetry of rotation.

  Instead of the three or four stabilizing flaps

  sators usual, the missile according to the invention has more than two at most. Compared to a stabilizer with four stabilizing flaps, this means that there are only two flaps opposite each other and enlarged accordingly. The stabilizing effect of the empennage is thus increased in one direction, but removed in the direction perpendicular to the latter. By judiciously choosing the speed of rotation around the missile's axis of symmetry, we can achieve a stable flight since the rotation is fast enough so that variations in stability cannot be felt in the flight mechanics. There remains an average stability. It has surprisingly been found that a missile comprising fewer than three flaps exhibits the stability of

  flight required although on at least one axis no stabilization

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  tion is only ensured by shutters. The prerequisite is that the frequency of the variation in stability is greater than the frequency of pitching or yawing of the missile and therefore that the missile is too inert around the transverse axes to react by aerodynamics and / or

  by flight mechanics with momentary variation in stability.

  Practical tests have shown that this principle works

  perfectly and that it saves two stable flaps

  reading lights (or at least one stabilizing flap).

  In the preferred embodiment, exactly two stabilizing flaps are placed one opposite the other. These flaps must be respectively identical with regard to their mass distribution so that no imbalance occurs during the rotation of the missile. The flaps are placed in a common plane passing

  by the longitudinal axis of the missile and provide stabilization

  sation transversely to this plane. Like the speed of

  rotation of this plane is significantly greater than the frequency

  of instabilities which depend on the inertia of the missile, these instabilities cannot cause a

change of course of the missile.

  The invention will be better understood using the

  description of embodiments taken as an example,

  but not limiting, and illustrated by the appended drawing, in which: - Figure 1 is a side view of a first embodiment of the missile;

  - Figure 2 is an elevational view of the em-

  pinning of a second embodiment;

  - Figure 3 is an elevational view of the em-

  tennage in the direction of arrow III in Figure 2.

  The missile shown in Figure 1 has

  an elongated cylindrical fuselage 10 which forms the casing-

  motor and at the front of which a warhead 101 is connected. At the rear end of the fuselage 10 is attached the nozzle 12

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  whose internal cross-section widens towards the rear. The nozzle 12 is surrounded by the tail 11 which

  is also attached to the rear end of the fuselage 10.

  The empennage 11 comprises two stabilizing flaps 13, 14 which extend in opposite directions and which are

  pivotally mounted on longitudinal axes 15. The

  mites before pivot axes 15 are fixed on the

  fuselage 10, the rear ends on a ring 21 surrounded

  rant the nozzle 12. The stabilizing flaps 13 and 14 are constituted by segments which can be folded down by rotation about the longitudinal axes 15. They respectively comprise a rigid (internal) construction element on which an elastic sheet (external) of so that the flaps in the folded state do not protrude outside the contour of the fuselage 10. This allows the missile to be fired from a cylindrical launch tube. At the outlet of the launch tube, the flaps 13, 14 under the action of the combined compression / torsion springs 16 which surround

  the respective longitudinal axes 15 are deployed laterally

  and stopped backwards. In the deployed state, the flaps 13, 14 according to FIG. 1 project beyond the outline of the fuselage 10 in opposite directions. The two stabilizing flaps 13, 14 are offset by 180

  relative to each other. In relation to the longitu-

  dinal of missile 10, the flaps are arranged obliquely

  in a known way the value of a small angle (angle of inci-

  dence) so that the missile, during its flight, rotates about its longitudinal axis. The speed of rotation depends on the mass inertia and the importance of the instabilities occurring. It is preferably

in the range of 15 to 30 Hz.

  In the embodiment of Figures 2 and 3, the two stabilizing flaps 13 and 14 are curved in a known manner in accordance with the peripheral curvature of the fuselage, so that in the folded state (in the tube of

  launch) they adapt to the contour of the fuselage.

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  Each of the stabilizing flaps 13, 14 is connected by an axis 17 to an arm-18 the other end of which is articulated on the longitudinal axis 15. The arms 18 are pre-tensioned by torsion springs 16 resting on the axes longitudinal 15 so that, at the outlet of the launching tube, they deviate approximately radially, the flaps 13, 14 being pivoted by the torsion springs 19 resting on the axes 17 until they are stopped by a stop (not shown). During the flight, the

  flaps 13, 14 are in the state shown in the figures

  res 2 and 3 in which - in the horizontal position of the missile shown in FIG. 3 - one of the flaps 13 is curved downwards, while the other flap 14 is curved upwards. As a result of the angle of incidence of the flaps, the missile rotates around its longitudinal axis in the

  direction of arrow 20 in FIG. 3.

  Depending on the configuration of the rear area of the

  missile and the stability conditions imposed on the empen-

  swimming with two stabilizing flaps, the flaps 14 and the arms 18 can form a single unit, so that the axes 17 and the torsion springs 19 can be

  delete. Therefore, in the case of an embodiment,

  rigid position - either decrease the segments 13 and 14 in the form of cylinder parts, or increase the curvature

segments.

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Claims (4)

  1. Missile provided with a tail unit which is placed at the rear end of its fuselage and which comprises stabilizing flaps deploying laterally during the flight and rotating around the axis of the fuselage at the same time as the latter or relative to that - characterized by   the fact that a maximum of two stabilizing flaps are provided   tors (13, 14) and that the speed of rotation is sensitive-   greater than the pitch or yaw frequencies due to inertia and caused by the asymmetry of rotation.   2. Missile according to claim 1, characterized in that exactly two stabilizing flaps (13,   14) are placed opposite one another.   3. Missile according to claim 1 or 2, charac-   terrified by the fact that the stabilizing flaps (13, 14) for causing a common rotation of the fuselage (10) and the tailplane (11) are arranged obliquely with respect to the direction of flight.   4. Missile according to any one of the claims   1 to 3, characterized in that the stabilized flaps   Readers (13, 14) can pivot relative to the fuser lage (10).