ADAPTIVE FAIL-FIXED SYSTEM FOR FADEC CONTROLLED GAS TURBINE ENGINES

• US 20110173988A1
• Filed: 11/13/2008
• Published: 07/21/2011
• Est. Priority Date: 11/13/2008
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Silder, Stephen H., Sweet, David H.
• Granted Patent: US 9,217,376 B2
• Time in Patent Office: Days
• US Class Current: 60/773
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: F02C 9/22 by adjusting turbine vanes
• CPC Class Codes: F02C 9/26 Control of fuel supply F02C9/48 takes precedence; fuel valves F02C7/232
• CPC Class Codes: F02C 9/263 by means of fuel metering valves
• CPC Class Codes: F02C 9/28 Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed F02C9/30 - F02C9/38, F02C9/44 take precedence
• CPC Class Codes: F02C 9/44 responsive to the speed of aircraft, e.g. Mach number control, optimisation of fuel consumption
• CPC Class Codes: F02C 9/46 Emergency fuel control
• CPC Class Codes: F05D 2270/09 to cope with emergencies
• CPC Class Codes: F05D 2270/094 by using back-up controls
• CPC Class Codes: F23N 2005/185 using detectors sensitive to rate of flow of fuel

Abstract

A gas turbine engine control system includes a module operable to fail-fix the gas turbine engine to one of a multiple of pre-determined modes in response to failure of an automatic control.

Claims

1. A gas turbine engine control system comprising:

an automatic control operable to control a gas turbine engine; and

a module operable to fail-fix the gas turbine engine to one of a multiple of pre-determined modes in response to failure of said automatic control.

2. The system as recited in claim 1, further comprising:

a fuel flow meter to sense a fuel flow to said engine;

a fuel control to control said fuel flow to said engine; and

said module in electrical communication with said fuel flow meter to fix said fuel control in response to said one of said multiple of pre-determined modes.

3. The system as recited in claim 2, wherein said one of said multiple of pre-determined modes are selected in part by a fuel flow sensed by said fuel flow meter.

4. The system as recited in claim 2, wherein said one of said multiple of pre-determined modes are selected in part by a compressor speed (NG) of said engine.

5. The system as recited in claim 1, further comprising:

an inlet guide vane actuator operable to control an inlet guide vane system of said engine;

said module in electrical communication with said inlet guide vane actuator to fix said inlet guide vane system in response to said one of said multiple of pre-determined modes.

6. The system as recited in claim 5, wherein said one of said multiple of pre-determined modes are selected in part by a fuel flow sensed by said fuel flow meter.

7. The system as recited in claim 5, wherein said one of said multiple of pre-determined modes are selected in part by a Compressor speed (NG) of said engine.

8. The system as recited in claim 1, wherein said automatic control includes a Full Authority Digital Engine Control (FADEC).

9. The system as recited in claim 8, wherein said module is remote from said FADEC.

10. The system as recited in claim 1, wherein said module includes hardwired circuitry.

11. The system as recited in claim 1, wherein said multiple of pre-determined modes includes a low fuel flow power mode, a moderate fuel flow power mode and a high fuel flow power mode.

12. The system as recited in claim 11 wherein said low fuel flow power mode includes shutdown of the engine.

13. The system as recited in claim 11, wherein said moderate fuel flow power mode includes operation of the engine at a predetermined fixed fuel flow rate.

14. The system as recited in claim 11, wherein said moderate fuel flow power mode includes fixing engine operation at a current fuel flow rate.

15. The system as recited in claim 11, wherein said high fuel flow power mode includes fixing the engine operation to an idle condition.

16. A method for transfer to a backup system in response to automatic engine control failure comprising:

identification of a loss of automatic engine control;

selecting one of a multiple of preprogrammed modes after the identification; and

operating a gas turbine engine in response to the selected preprogrammed mode.

17. A method as recited in claim 16, further comprising:

selecting the one of the multiple of preprogrammed modes in response to at least one input from a sensor system.

18. A method as recited in claim 16, further comprising:

selecting the one of the multiple of preprogrammed modes in response to a fuel flow in response to an the idealized compressor speed (Ng) to Fuel Flow relationship.

19. A method as recited in claim 16, further comprising:

operating the gas turbine at a predetermined fixed fuel flow in response to the selected preprogrammed mode.

20. A method as recited in claim 19, further comprising:

slewing the fuel flow from the fuel flow at the identification of the loss of automatic engine control to the predetermined fixed fuel flow in response to the selected preprogrammed mode.