Solid rocket motors including flight termination systems, and related multi-stage solid rocket motor assemblies and methods

Patent metadata

Field	Value
Publication number	US-10781773-B2
Application number	US-201514932895-A
Country	US
Kind code	B2
Filing date	Nov 4, 2015
Priority date	Nov 4, 2015
Publication date	Sep 22, 2020
Grant date	Sep 22, 2020

Abstract

A solid rocket motor comprises a pressure vessel, a solid propellant structure within the pressure vessel, and a flight termination system overlying the pressure vessel. The flight termination system comprises a shaped charge configured and positioned to effectuate ignition of an inner portion of the solid propellant structure and a reduction in an ability of the pressure vessel to withstand a change in internal pressure. Another solid rocket motor, a multi-stage rocket motor assembly, and a method of destroying a launch vehicle in flight are also described.

First claim

What is claimed is:

1. A solid rocket motor, comprising:
a pressure vessel;
a solid propellant structure within the pressure vessel;
a bore longitudinally extending through the solid propellant structure;
a slot in communication with an end of the bore and exhibiting a radial end proximate a sidewall of the pressure vessel, the radial end of the slot longitudinally extending across less than an entirety of the bore, and an outer boundary of the slot tapering toward the bore from the radial end of the slot; and
a flight termination system overlying the pressure vessel and comprising a shaped charge positioned over and laterally aligned with the radial end of the slot and configured to effectuate ignition of an inner portion of the solid propellant structure at the bore and a reduction in an ability of the pressure vessel to withstand a change in internal pressure.

2. The solid rocket motor of claim 1 , wherein the shaped charge is configured and positioned to cut through portions of the pressure vessel and the solid propellant structure overlying the radial end of the slot and to at least partially cut through additional portions of the pressure vessel laterally aligned with but longitudinally offset from radial end of the slot.

3. The solid rocket motor of claim 1 , wherein the shaped charge comprises a linear shaped charge.

4. The solid rocket motor of claim 3 , wherein the flight termination system further comprises a conditioning structure configured to reduce damage to the pressure vessel effectuated by the linear shaped charge, the conditioning structure separate from and only partially interposed between the linear shaped charge and an external surface of the pressure vessel across longitudinal dimensions of the linear shaped charge and the pressure vessel.

5. The solid rocket motor of claim 4 , wherein the conditioning structure comprises at least one material positioned between a portion of the linear shaped charge and an underlying portion of the pressure vessel, the material longitudinally extending across less than an entirety of the linear shaped charge.

6. The solid rocket motor of claim 1 , wherein an entirety of the shaped charge is positioned over the sidewall of the pressure vessel.

7. The solid rocket motor of claim 1 , wherein the shaped charge is oriented parallel to a central longitudinal axis of the solid rocket motor.

8. A solid rocket motor, comprising:
a skirt structure;
a pressure vessel discrete from and contained within the skirt structure;
a nozzle assembly connected to the skirt structure and an aft end of the pressure vessel;
a solid propellant structure within the pressure vessel;
a bore longitudinally extending through the solid propellant structure;
a slot in communication with an aft end of the bore and exhibiting a radial end longitudinally proximate an aft end of the pressure vessel, the slot outwardly tapering from a location along the bore more longitudinally distal from the aft end of the pressure vessel to the radial end thereof; and
a flight termination system comprising:
a first shaped charge overlying one or more of the skirt structure and the pressure vessel, the first shaped charge positioned over and laterally aligned with the radial end of the slot and configured to effectuate ignition of the solid propellant structure at the aft end of the bore; and
a second shaped charge overlying the skirt structure and spaced apart from the first shaped charge, the second shaped charge configured and positioned to effectuate a reduction in an ability of the pressure vessel to withstand a change in internal pressure.

9. The solid rocket motor of claim 8 , wherein:
the first shaped charge is configured and positioned to cut through portions of the pressure vessel and the solid propellant structure overlying the radial end of the slot; and
the second shaped charge is configured and positioned to cut through portions of the skirt structure and additional portions of the pressure vessel not overlying the radial end of the slot.

10. The solid rocket motor of claim 8 , wherein:
the first shaped charge is located over the aft end of the pressure vessel at a position aligned with the radial end of the slot; and
the second shaped charge is located over a tubular sidewall of the skirt structure.

11. The solid rocket motor of claim 8 , wherein:
the first shaped charge comprises a conical shaped charge; and
the second shaped charge comprises a linear shaped charge.

12. The solid rocket motor of claim 8 , wherein the second shaped charge is oriented perpendicular to a central longitudinal axis of the solid rocket motor.

13. The solid rocket motor of claim 8 , further comprising a third shaped charge at another position over the skirt structure opposing a position of the second shaped charge.

14. A multi-stage rocket motor assembly, comprising:
an outer housing; and
a plurality of stages in a stacked arrangement within the outer housing, at least one stage of the plurality of stages comprising:
a pressure vessel;
a solid propellant structure within the pressure vessel;
a bore longitudinally extending through the solid propellant structure;
a slot in communication with an end of the bore and exhibiting a radial end proximate a sidewall of the pressure vessel, the radial end of the slot longitudinally extending across less than an entirety of the bore, and an outer boundary of the slot tapering toward the bore from the radial end of the slot; and
a flight termination system overlying the pressure vessel and comprising at least one shaped charge positioned over and aligned with the radial end of the slot and configured to effectuate ignition of an inner portion of the solid propellant structure at the bore and a reduction in an ability of the pressure vessel to withstand a change in internal pressure.

15. The multi-stage rocket motor assembly of claim 14 , wherein the at least one shaped charge is configured and positioned to cut through portions of the pressure vessel and the solid propellant structure overlying the radial end of the slot and to at least partially cut through additional portions of at least the pressure vessel not overlying the radial end of the slot.

16. The multi-stage rocket motor assembly of claim 14 , wherein the at least one shaped charge comprises:
at least one conical shaped charge positioned at an aft end of the pressure vessel and overlying the radial end of the slot; and
at least one linear shaped charge discrete from the at least one conical shaped charge and overlying the sidewall of the pressure vessel.

17. The multi-stage rocket motor assembly of claim 14 , wherein the at least one shaped charge comprises a linear shaped charge positioned over the sidewall of the pressure vessel.

18. The multi-stage rocket motor assembly of claim 17 , wherein the flight termination system further comprises a conditioning structure separate from and only partially interposed between the linear shaped charge and the sidewall of the pressure vessel across longitudinal dimensions of the linear shaped charge and the pressure vessel.

19. The multi-stage rocket motor assembly of claim 14 , wherein at least one other stage of the plurality of stages comprises:
another pressure vessel;
another solid propellant structure within the another pressure vessel; and
an additional flight termination system overlying the another pressure vessel and comprising at least one additional shaped charge configured and positioned to effectuate ignition of an inner portion of the another s

Assignees

• Northrop Grumman Innovation Systems Inc

Inventors

• Kliger Joseph J
• Braithwaite Paul C
• Liechty Brian C
• Patterson Donald B

Classifications

• B64G1/52

  Protection, safety or emergency devices; Survival aids · CPC title

• F02K9/763

  with solid propellant · CPC title

• F02K9/26

  Burning control {(F02K9/10, F02K9/34, F02K9/86, F02K9/92 and F02K9/94 take precedence)} · CPC title

• F02K9/10

  Shape or structure of solid propellant charges · CPC title

• F02K9/38

  Safety devices, e.g. to prevent accidental ignition · CPC title