Multi-stage rocket motor assembly including jettisonable launch motor integrated with flight igniter

• US 6,481,198 B1
• Filed: 06/27/2000
• Issued: 11/19/2002
• Est. Priority Date: 07/09/1999
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Innovation Systems, Inc. (Northrop Grumman Corporation)
• Original Assignee: Alliant Techsystems Incorporated (Northrop Grumman Corporation)
• Inventors: Miskelly, Herman L., Hepler, Sheryl H., Horton, Mark C.
• Primary Examiner(s): Casaregola, Louis J.
• Application Number:
  US09/604,679
• Time in Patent Office: 875 Days
• Field of Search: 602/25, 602/44, 602/45, 602/51, 602/56
• US Class Current: 60/245
• CPC Class Codes: F02K 9/95 characterised by starting or ignition means or arrangements safety devices F02K9/38
• CPC Class Codes: F02K 9/978 Closures for nozzles; Nozzles comprising ejectable or discardable elements

Abstract

This multi-stage rocket motor assembly includes, a one main motor subassembly and a launch motor subassembly. The flight igniter of the main motor subassembly is integrated with the launch motor subassembly to permit the flight igniter to be jettisoned essentially in unison with the launch motor subassembly.

Claims

1. A multi-stage rocket motor assembly comprising:

at least one main motor subassembly comprising at least one flight igniter, a main motor case structure containing at least one main combustion chamber loaded with at least one main propellant which is ignitable by said flight igniter, and a nozzle subassembly defining a combustion product passage in communication with said combustion chamber, said combustion product passage including a throat portion and an aft exhaust portion; and

at least one launch motor subassembly comprising at least one launch igniter and a launch motor case structure, said launch motor case structure housing at least one launch combustion chamber loaded with at least one launch propellant which is ignitable by said launch igniter, said launch motor subassembly and said nozzle subassembly being detachably connected to permit both detachment of said launch motor subassembly from at least said nozzle subassembly while said rocket motor assembly is in flight and jettisoning of said launch motor subassembly after initiation of said main propellant,

wherein said flight igniter is integrated with said launch motor subassembly to permit said flight igniter to be jettisoned essentially in unison with said launch motor subassembly, and

wherein said launch motor subassembly does not extend substantially beyond said aft end portion of said nozzle subassembly.

2. The rocket motor assembly of claim 1, wherein said main propellant comprises a hybrid system comprising at least one solid fuel and at least one liquid oxidizer.

3. The rocket motor assembly of claim 1, wherein said main propellant comprises a reverse hybrid system comprising at least one solid oxidizer and at least one liquid fuel.

4. The rocket motor assembly of claim 1, wherein said main motor subassembly comprises a sustain motor subassembly and wherein said launch motor subassembly comprises a boost motor subassembly.

5. The rocket motor assembly of claim 1, wherein said main propellant and said launch propellant each comprise a respective solid propellant grain.

6. The rocket motor assembly of claim 1, wherein said launch motor case structure extends through and is detachably retained by the throat portion of the nozzle subassembly.

7. A multi-stage rocket motor assembly comprising:

at least one main motor subassembly comprising at least one flight igniter, a main motor case structure containing at least one main combustion chamber loaded with at least one main propellant which is ignitable by said flight igniter, and a nozzle subassembly defining a combustion product passage in communication with said combustion chamber, said combustion product passage including a throat portion and an aft exhaust portion; and

at least one launch motor subassembly comprising at least one launch igniter and a launch motor case structure, said launch motor case structure housing at least one launch combustion chamber loaded with at least one launch propellant which is ignitable by said launch igniter, said launch motor subassembly and said nozzle subassembly being detachably connected for detaching said launch motor subassembly from at least said nozzle subassembly while said rocket motor assembly is in flight and for jettisoning said launch motor subassembly after initiation of said main propellant,

wherein said flight igniter is integrated with said launch motor subassembly for jettisoning said flight igniter essentially in unison with said launch motor subassembly, and

wherein said launch combustion chamber and said launch propellant are substantially housed in said main motor subassembly.

8. The rocket motor assembly of claim 7, wherein said main propellant comprises a hybrid system comprising at least one solid fuel and at least one liquid oxidizer.

9. The rocket motor assembly of claim 7, wherein said main propellant comprises a reverse hybrid system comprising at least one solid oxidizer and at least one liquid fuel.

10. The rocket motor assembly of claim 7, wherein said main motor subassembly comprises a sustain motor subassembly and wherein said launch motor subassembly comprises a boost motor subassembly.

11. The rocket motor assembly of claim 7, wherein said main propellant and said launch propellant each comprise a respective solid propellant grain.

12. The rocket motor assembly of claim 7, wherein said launch motor case structure extends through and is detachably retained by the throat portion of the nozzle subassembly.

13. A multi-stage rocket motor assembly comprising:

at least one main motor subassembly comprising at least one flight igniter, a main motor case structure containing at least one main combustion chamber loaded with at least one main propellant which is ignitable by said flight igniter, and a nozzle subassembly defining a combustion product passage in communication with said combustion chamber, said combustion product passage including a throat portion and an aft exhaust portion; and

at least one launch motor subassembly comprising at least one launch igniter and a launch motor case structure, said launch motor case structure housing at least one launch combustion chamber loaded with at least one launch propellant which is ignitable by said launch igniter, said launch motor subassembly and said nozzle subassembly being detachably connected for detaching said launch motor subassembly from at least said nozzle subassembly while said rocket motor assembly is in flight and for jettisoning said launch motor subassembly after initiation of said main propellant,

wherein said flight igniter is integrated with said launch motor subassembly for jettisoning said flight igniter essentially in unison with said launch motor subassembly, and

wherein said launch motor case structure extends through and is detachably retained by the throat portion of the nozzle subassembly.

14. The rocket motor assembly of claim 13, wherein said main propellant comprises a hybrid system comprising at least one solid fuel and at least one liquid oxidizer.

15. The rocket motor assembly of claim 13, wherein said main propellant comprises a reverse hybrid system comprising at least one solid oxidizer and at least one liquid fuel.

16. The rocket motor assembly of claim 13, wherein said main motor subassembly comprises a sustain motor subassembly and wherein said launch motor subassembly comprises a boost motor subassembly.

17. The rocket motor assembly of claim 13, wherein said main propellant and said launch propellant each comprise a respective solid propellant grain.