AIRCRAFT, PROPULSION SYSTEM, AND SYSTEM FOR TAXIING AN AIRCRAFT

• US 20120119020A1
• Filed: 11/16/2010
• Published: 05/17/2012
• Est. Priority Date: 11/16/2010
• Status: Active Grant

• Current Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Inventors: Rajashekara, Kaushik, Burns, Donald
• Granted Patent: US 8,684,304 B2
• Time in Patent Office: Days
• US Class Current: 244/58
• CPC Class Codes: B64D 2205/00 Aircraft with means for ground manoeuvring, such as taxiing, using an auxiliary thrust system, e.g. jet-engines, propellers or compressed air
• CPC Class Codes: B64D 27/00 Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
• CPC Class Codes: B64D 33/00 Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
• CPC Class Codes: B64D 35/00 Transmitting power from power plants to propellers or rotors; Arrangements of transmissions
• CPC Class Codes: F02C 7/32 Arrangement, mounting, or driving, of auxiliaries
• CPC Class Codes: F02C 7/36 Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user F02C3/107 - F02C3/13 and F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y02T 50/80 Energy efficient operational measures, e.g. ground operations or mission management

Abstract

One embodiment of the present invention is a unique aircraft. Another embodiment is a unique aircraft propulsion system. Still another embodiment is a unique system for taxiing an aircraft without starting one or more main aircraft propulsion engines. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for aircraft taxiing and propulsion systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

Claims

1. A propulsion system for an aircraft, comprising:

a gas turbine engine having a high pressure (HP) spool and a low pressure (LP) spool, wherein the LP spool is operative to drive a propulsor;

an auxiliary power unit (APU) mechanically coupled to the LP spool and operative to drive the LP spool;

an auxiliary electrical machine mechanically coupled to LP spool and operative to drive the LP spool; and

an electrical power source electrically coupled to the auxiliary electrical machine,

wherein the APU and the auxiliary electrical machine are configured and operative to jointly supply rotational power to the LP spool to generate thrust via the propulsor for taxiing the aircraft.

2. The propulsion system of claim 1, wherein the electrical power source is a battery.

3. The propulsion system of claim 1, wherein the electrical power source is a fuel cell.

4. The propulsion system of claim 1, wherein the electrical power source is a combination of a fuel cell and a battery.

5. The propulsion system of claim 1, wherein the APU is a hybrid APU having an APU compressor;

an APU turbine; and

a fuel cell fluidly disposed between the APU compressor and the APU turbine, wherein the fuel cell is operative to receive as an oxidant air pressurized by the APU compressor;

to generate electrical power using a fuel and the oxidant;

to heat the air pressurized by the APU compressor; and

to discharge the heated pressurized air into the APU turbine.

6. The propulsion system of claim 1, further comprising an auxiliary combining gearbox mechanically coupled to the APU, the auxiliary electrical machine and the gas turbine engine.

7. The propulsion system of claim 6, wherein the auxiliary combining gearbox is configured to transmit mechanical power from the auxiliary electrical machine to the APU for starting the APU.

8. The propulsion system of claim 6, wherein the auxiliary combining gearbox is configured to transmit mechanical power from the APU to the auxiliary electrical machine for generating electrical power.

9. The propulsion system of claim 6, wherein the auxiliary combining gearbox is configured to transmit mechanical power from the APU to the gas turbine engine.

10. The propulsion system of claim 6, wherein the auxiliary combining gearbox is configured to transmit mechanical power from the auxiliary electrical machine to the gas turbine engine.

11. The propulsion system of claim 6, wherein the auxiliary combining gearbox is configured to transmit mechanical power from both the auxiliary electrical machine and the APU to the gas turbine engine.

12. The propulsion system of claim 1, wherein the gas turbine engine includes a gearbox;

wherein the APU is mounted on the gearbox; and

wherein the gearbox is configured to transfer power from the APU to the HP spool for starting the gas turbine engine.

13. The propulsion system of claim 12, wherein the gearbox is configured to transfer power from the APU and the auxiliary electrical machine to the HP spool for starting the gas turbine engine.

14. The propulsion system of claim 1, wherein the gas turbine engine includes a gearbox;

wherein the APU is mounted on the gearbox; and

wherein the gearbox is configured to transfer power from the APU and the auxiliary electrical machine to the LP spool to generate thrust via the propulsor for taxiing the aircraft.

15. An aircraft, comprising:

a fuselage;

an empennage coupled to the fuselage;

a plurality of wings coupled to the fuselage; and

a propulsion system, including;

a gas turbine engine having a high pressure (HP) spool and a low pressure (LP) spool and an engine gearbox, wherein the LP spool is operative to drive a propulsor; and

wherein the gas turbine engine is coupled to at least one of the fuselage, the empennage and at least one of the plurality of wings;

an auxiliary power unit (APU) mechanically coupled to the LP spool via the gearbox and operative to drive the LP spool;

an auxiliary electrical machine mechanically coupled to LP spool via the gearbox and operative to drive the LP spool;

an electrical power source electrically coupled to the auxiliary electrical machine,

wherein the APU and the auxiliary electrical machine are configured and operative to jointly supply rotational power via the engine gearbox to the LP spool to generate thrust via the propulsor for taxiing the aircraft.

16. The aircraft of claim 15, wherein the engine gearbox is also configured to mechanically couple the APU to the HP spool for starting the gas turbine engine.

17. The aircraft of claim 16, wherein the engine gearbox is configured to mechanically couple the auxiliary electrical machine to the HP spool to starting the gas turbine engine.

18. The aircraft of claim 15, further comprising an engine electrical machine mounted on the HP spool and electrically coupled to at least one of the electrical power source and the auxiliary electrical machine, wherein the engine electrical machine, and the at least one of the electrical power source and the auxiliary electrical machine are configured to start the gas turbine engine by supplying electrical power to the engine electrical machine, whereby the engine electrical machine imparts rotation to the HP spool sufficient to start the gas turbine engine.

19. The aircraft of claim 15, wherein the electrical power source is at least one of a fuel cell and a battery.

20. The aircraft of claim 15, wherein the electrical power source is a combination of a fuel cell and a battery.

21. The aircraft of claim 15, wherein the APU is a hybrid APU having an APU compressor;

an APU turbine; and

a fuel cell fluidly disposed between the APU compressor and the APU turbine, wherein the fuel cell is operative to receive as an oxidant air pressurized by the APU compressor;

to generate electrical power using a fuel and the oxidant;

to heat the air pressurized by the APU compressor; and

to discharge the heated pressurized air into the APU turbine.

22. A system, comprising:

a gas turbine engine having a high pressure (HP) spool and a low pressure (LP) spool, wherein the LP spool is operative to drive a propulsor; and

means for supplying mechanical power from at least two sources to the low pressure spool for taxiing an aircraft.

23. The system of claim 22, wherein the two sources include an auxiliary power unit (APU) and an auxiliary electrical machine, wherein the auxiliary electrical machine is powered by at least one of a fuel cell and a battery.

24. The system of claim 23, wherein the APU is a hybrid APU employing the fuel cell in the APU thermodynamic cycle.