DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-4, 10-14 and 20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “quick relights” in claim 1 is a relative term which renders the claim indefinite. The term “quick” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The term quick relight does not appear to be a standard in the gas turbine arts. Thus one of ordinary skill would not know how to avoid infringing the claim. Claim 11 recites a similar limitation and is rejected for the same reasons. For example NPL Lieuwen cited below in the 102 and 103 sections discusses under 1 minute as a quick relight; US 20230138892 A1 discusses quick relight regarding 5 seconds (see par. 106); and US 20170096233 A1 discusses “quick restart” regarding 10 to 60 seconds (see par. 72).
Claim 1 recites “maintain high spool speed”. The metes and bounds of this phrase appears to be unclear in light of applicant specification. For example par. 65 states “a high spool motor of the hybrid electrically operated engine can be controlled to maintain high spool speed of the electrically operated engine for restart/relight”. The plain meaning of this is maintain the speed of the high spool. However throughout applicant specification the term “high speed spool” is used when referring to the spool and “high spool” is used when referring to the motor. Thus examiner was not sure if it was intended that the specification communicate (1) “maintain high speed spool speed of the …” or (2) “maintain high speed spool of the …”. For purposes of examination the claim is interpreted for each scenario (1) and (2). Claim 11 recites a similar limitation and is rejected for the same reasons.
Claim(s) dependent thereon are rejected for the same reasons.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1, 2, 10-12 and 20 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Hiett (2022/0063826), as evidenced by NPL Gas Turbine Emissions (Lieuwen), Pub. No.: US 2021/0025339 A1 (Terwilliger), Pub. No.: US 2018/0128182 A1 (Hayama) and Pub. No.: US 2012/0119020 A1 (Burns).
Regarding claim 1, Hiett discloses (see figs. 1 and 4) a system comprising:
a gas turbine engine 10,100 of an aircraft (see abstract), the gas turbine engine 10,100 comprising a low speed spool 55, a high speed spool 32 (see par. 34) and a combustor 40;
a high spool motor 102B configured to augment rotational power (electric machines 102A,102B are used to add power 204; see par. 72 and fig. 4) of the high speed spool 32; and
a controller (electronic engine controller 116, i.e., FADEC, see par. 53) configured (controller controls low and high motors 102A,102B; see par. 69 and see controller 116 connected to motors for example in embodiment of fig. 3, wherein controller 116 is also shown in fig. 1) to:
control the high spool motor 102B to drive rotation (adding power 204 can be with high spool motor 102B with or without a low spool motor 102A; see par. 72 and fig. 4) of the high speed spool 32 to maintain a desired compressor pressure (the pressure of air required for ignition, see par. 28, top, regarding mid-flight restart 218 that is included with adding power 204, see fig. 4, the high spool motor 102B is used for a mid-flight restart 218, see par. 78, pointing out that the starter system may not be available; also see fig. 4 regarding restart 218; the instant desired pressure is that pressure needed for ignition wherein the “speed” at par. 28, top results in the instant desired pressure as evidenced by Terwilliger; Terwilliger points out in pars. 44 and 45: “In engine start …, the high spool motor … can be used to increase the speed of the high speed spool … for light off” and “ using the high spool motor … to control the high speed spool … to provide sufficient compression in the gas turbine engine … for light off in the combustor”) and a desired flow (there is a flow corresponding with the desired pressure; regulating the speed of the HP compressor provides sufficient flow into the combustor (see par. 28) to facilitate a relighting (see par. 79); in addition the desired flow through the combustor when the fuel flow is off provides sufficient cooling (see par. 85) to the turbine (air goes through combustor 40 and turbines (36, 42) to cool the turbines resulting in lower EGT’s during restart that makes the restart attempt more reliable (see par. 83))) within the combustor 40, wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts including quick relights (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL; “holding” for quick relight is confirmed by fig. 8 wherein the relight occurs at 30 seconds after in-flight shutdown 210 wherein high spool motor and low speed motor supplies power1 to high pressure spool and the low pressure spool (see line 208) wherein the relight at 30 seconds occurred at about 28% speed; fig. 10 shows high speed spool 204 held at about 28% speed from time = 40 seconds to time = 200 seconds and thus the claimed “maintaining” feature is met), and wherein the controller controls the high spool motor to maintain high spool speed of the gas turbine engine for restart/relight2 (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL), in order to provide thrust (both, see par. 72, the low spool motor 102A and the high spool motor 102B are adding power 204 to the gas turbine engine 10,100; par. 39 points out that thrust is created when the rotor assembly 12 is driven by the low speed spool 55; the low speed spool 55 is driven by the low spool motor, see par. 72; thus thrust is created; a component of the thrust is created by the high spool motor 102B; this is evidenced by Terwilliger in par. 47 regarding “motor-based thrust” and also evidenced by Burns in par. 23: “The rotational power supplied to HP spool 24 reduces drag on the rotation of LP spool 26, and may result in a secondary taxiing thrust component being produced by HP spool 24”; thus one of ordinary skill understands that driving the high spool with the high spool motor reduces the internal aerodynamic drag because the compressed air exiting the low pressure compressor is not used to drive the high pressure compressor and thus the high spool motor contributes to thrust; Burns refers to a taxiing thrust however a POSITA understands that this idea of electric motors overcoming engine aerodynamic drag also is applicable to flight scenarios as pointed out in the pertinent prior art of the office action mailed 02/20/2026 on page 21-22) while operating the gas turbine engine in an electrically powered (both, see par. 72, both instant electric motors 102A,102B are adding power 204) in flight mode (adding power 204 takes place during a “flight” because an actual in-flight shutdown 202 precedes the adding power 204; see fig. 4) while the controller 116 does not command fuel flow (the gas turbine engine has been shutdown 202 and thus no fuel is provided to the combustor, Hayama is evidence that the fuel valve 72 is off when the engine is off or shutdown; Hayama explains in pars. 41 and 42, when a gas turbine engine is off, the fuel valve providing fuel to the engine is closed and when the in-flight restart is initiated, then the fuel valve is opened; Hayama points out that FADEC controllers control the fuel valve, see pars. 31 and 35; thus, one skilled in the art would understand that the fuel valve of Hiett is closed when the engine is off during the electrically powered mode when power is added by the electric motors) to the combustor 40 and the gas turbine engine 10,100 is operating in a no fuel mode; and
command, responsive to a trigger event (in paragraph 77, Hiett points out that there has come a time during a flight such that a higher thrust is needed (determination that a requested thrust exceed an amount of thrust that the gas turbine engine is delivering in the electric mode) and therefore a restart of the gas turbine engine is triggered) to cause the gas turbine engine 10,100 to start to a fuel-burning mode (Hiett fuel valve 72 is opened during starting as evidenced by Hayama discussed above), wherein the trigger event a determination that a requested (the Hiett FADEC 116 receives a thrust request and operates the fuel valve 72 accordingly; the thrust request received by the FADEC can be from a pilot control or from an auto-pilot; this is evidenced by Terwilliger par. 50 bottom pointing out that FADEC 256 receives a thrust request in form of a throttle lever angle via the instant pilot control or auto-pilot) thrust exceeds an amount of thrust (there came a time when the higher thrust is needed for the higher thrust maneuvers; see par. 77) that the gas turbine engine 10,100 can deliver while operating the gas turbine engine 10,100 in the electrically powered (see par. 72) in flight mode 204 while the controller (FADEC 116) does not command fuel flow (fuel valve 72 is closed as evidenced by Hayama above) to the combustor 40 and the gas turbine 10,100 is operating in the no fuel mode (fuel valve 72 is closed).
Regarding claim 11, Hiett discloses (see figs. 1 and 4) a method for a hybrid electric single engine descent restart comprising:
controlling (with controller 116; controller 116 controls low and high motors 102A,102B; see par. 69 and see controller 116 connected to motors for example in embodiment of fig. 3, wherein controller 116 is also shown in fig. 1) a high spool motor 102B of an aircraft (see abstract) to cause the high spool motor 102B to drive rotation of a high speed spool 32 of a gas turbine engine 10,100 of the aircraft to maintain a desired compressor pressure (the pressure of air required for ignition, see par. 28, top, regarding mid-flight restart 218 that is included with adding power 204, see fig. 4, the high spool motor 102B is used for a mid-flight restart 218, see par. 78, pointing out that the starter system may not be available; also see fig. 4 regarding restart 218; the instant desired pressure is that pressure needed for ignition wherein the “speed” at par. 28, top results in the instant desired pressure as evidenced by Terwilliger; Terwilliger points out in pars. 44 and 45: “In engine start …, the high spool motor … can be used to increase the speed of the high speed spool … for light off” and “ using the high spool motor … to control the high speed spool … to provide sufficient compression in the gas turbine engine … for light off in the combustor”) and a desired flow (there is a flow corresponding with the desired pressure; regulating the speed of the HP compressor provides sufficient flow into the combustor (see par. 28) to facilitate a relighting of the engine when for example a greater thrust is needed and wherein the speeds achieved by using the HP motor improve start reliability (see par. 79); in addition the desired flow through the combustor when the fuel flow is off provides sufficient cooling (see par. 85) to the turbine (air goes through combustor 40 and turbines (36, 42) to cool the turbines resulting in lower EGT’s during restart that makes the restart attempt more reliable (see par. 83))) within a combustor 40, wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts including quick relights (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL), and wherein the high spool motor is controlled to maintain high spool speed of the gas turbine engine for restart/relight (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL), of the gas turbine engine 10,100 in order to provide thrust (both, see par. 72, the low spool motor 102A and the high spool motor 102B are adding power 204 to the gas turbine engine 10,100; par. 39 points out that thrust is created when the rotor assembly 12 is driven by the low speed spool 55; the low speed spool 55 is driven by the low spool motor, see par. 72; thus thrust is created; a component of the thrust is created by the high spool motor 102B; this is evidenced by Terwilliger in par. 47 regarding “motor-based thrust” and also evidenced by Burns in par. 23: “The rotational power supplied to HP spool 24 reduces drag on the rotation of LP spool 26, and may result in a secondary taxiing thrust component being produced by HP spool 24”; thus one of ordinary skill understands that driving the high spool with the high spool motor reduces the internal aerodynamic drag because the compressed air exiting the low pressure compressor is not used to drive the high pressure compressor and thus the high spool motor contributes to thrust; Burns refers to a taxiing thrust however a POSITA understands that this idea of electric motors overcoming engine aerodynamic drag also is applicable to flight scenarios as pointed out in the pertinent prior art of the office action mailed 02/20/2026 on page 21-22) while operating the gas turbine engine in an electrically powered (both, see par. 72, both instant electric motors 102A,102B are adding power 204) in flight mode (adding power 204 takes place during a “flight” because an actual in-flight shutdown 202 precedes the adding power 204; see fig. 4) while a controller does not command fuel flow (the gas turbine engine has been shutdown 202 and thus no fuel is provided to the combustor, Hayama is evidence that the fuel valve 72 is off when the engine is off or shutdown; Hayama explains in pars. 41 and 42, when a gas turbine engine is off, the fuel valve providing fuel to the engine is closed and when the in-flight restart is initiated, then the fuel valve is opened; Hayama points out that FADEC controllers control the fuel valve, see pars. 31 and 35; thus, one skilled in the art would understand that the fuel valve of Hiett is closed when the engine is off during the electrically powered mode when power is added by the electric motors) to the combustor 40 and the gas turbine engine is operating in a no fuel mode; and
commanding fuel flow to the combustor responsive to a trigger event (in paragraph 77, Hiett points out that there has come a time during a flight such that a higher thrust is needed (determination that a requested thrust exceed an amount of thrust that the gas turbine engine is delivering in the electric mode) and therefore a restart of the gas turbine engine is triggered) to cause the gas turbine engine to start to a fuel-burning mode (Hiett fuel valve 72 is opened during starting as evidenced by Hayama discussed above), wherein the trigger event is a determination that a requested (the Hiett FADEC 116 receives a thrust request and operates the fuel valve 72 accordingly; the thrust request received by the FADEC can be from a pilot control or from an auto-pilot; this is evidenced by Terwilliger par. 50 bottom pointing out that FADEC 256 receives a thrust request in form of a throttle lever angle via the instant pilot control or auto-pilot) thrust exceeds an amount of thrust (there came a time when the higher thrust is needed for the higher thrust maneuvers; see par. 77) that the gas turbine engine 10,100 can deliver while operating the gas turbine engine in the electrically powered (see par. 72) in flight mode 204 while the controller (FADEC 116) does not command fuel flow (fuel valve 72 is closed as evidenced by Hayama above) to the combustor 40 and the gas turbine engine 10,100 is operating in the no fuel mode (fuel valve 72 is closed).
Regarding claim 2, Hiett discloses (see fig. 1) a low spool motor 102A configured to augment rotational power (see par. 72) of the low speed spool 55, wherein the controller 116 is configured (controller controls low and high motors 102A,102B; see par. 69 and see controller 116 connected to motors for example in embodiment of fig. 3, wherein controller 116 is also shown in fig. 1) to control the low spool motor 102A to drive rotation of the low speed spool 55.
Regarding claims 10 and 20, Hiett discloses (see fig. 1) a compressor pressure is determined based on a sensed pressure (sensor 114b). Sensor 114B measures a parameter of the high pressure system that includes the high pressure compressor 34 just upstream of the combustor 40. The top portion of par. 54 points out that the parameters of the high pressure system may be “pressures”. Thus Hiett discloses measuring a compressor pressure corresponding with the claimed desired compressor pressure for combustion of Hiett. Hiett further discloses (see figs. 4, 5 and 7-10) the desired flow is determined based on modeling a plurality of parameters about the gas turbine engine (the desired flow is based on adding power 204; adding power includes modeling (see for example plots in figs. 5 and 8-10) of altitude (i.e. “30kft”), amount of power (i.e., “hp”), airspeed (i.e., “knots”), and duration of applied power before relight (i.e. “time” or e.g. “30s”); also see “exhaust gas temperature” (fig. 7).
Regarding claim 12, Hiett discloses (see fig. 1) controlling (with controller 116; controller 116 controls low and high motors 102A,102B; see par. 69 and see controller 116 connected to motors for example in embodiment of fig. 3, wherein controller 116 is also shown in fig. 1) a low spool motor 102A configured to augment rotational power (see par. 72) of a low speed spool 55 of the gas turbine engine 10,100, wherein the low spool motor 102A to drives rotation of the low speed spool 55.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1-4, 10-14 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Terwilliger, as evidenced by US 20200307811 A1 (Shang), in view of Hiett as evidenced by Lieuwen.
Regarding claim 1 Terwilliger discloses (see figs. 1-3 and 6) a system comprising:
a gas turbine engine 100 of an aircraft 10, the gas turbine engine 10 comprising a low speed spool 30, a high speed spool 32, and a combustor 56;
a high spool motor 12B configured to augment rotational power (see par. 33, top) of the high speed spool 32; and
a controller 256 configured to:
control (see par. 43) the high spool motor 12B to drive rotation of the high speed spool 32 to maintain a desired compressor pressure (sufficient compression, i.e., sufficient pressure of air compressed by the high pressure compressor 52 for ignition in the combustor 56; see par. 45, middle) and a desired flow (there is a flow corresponding with the desired pressure and this is evidenced by Hiett; Hiett points out regulating the speed of the HP compressor provides sufficient flow into the combustor (see par. 28) to facilitate a relighting (see par. 79); in addition the desired flow through the combustor when the fuel flow is off provides sufficient cooling (see par. 85) to the turbine (air goes through combustor 40 and turbines (36, 42) to cool the turbines resulting in lower EGT’s during restart that makes the restart attempt more reliable (see par. 83))) within the combustor 56, wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts (see par. 45: “using the high spool motor 12B to control the high speed spool 32 to provide sufficient compression in the gas turbine engine 20 for light off in the combustor 56”; and see par. 51: “The starting operation can be… an in-flight restart”) including relights (see par. 51), and wherein the controller controls the high spool motor to maintain the high spool speed of the gas turbine engine for restart/relight3 (see pars. 45 and 51; the claim does not specify an amount of time regarding the holding and maintaining; thus Terwilliger meets the claim because maintains the high motor sufficiently for restart and relight), in order to provide thrust while operating the gas turbine engine in an electrically powered in flight mode (such a flight mode is shown at block 604 in fig. 6 wherein the high spool motor 12B is operated in parallel with the low speed motor 12A for (1) engine starting to a fuel burn mode or (2) during other scenarios wherein “The controller 256 can be configured to control a thrust response of the gas turbine engine 20 to a response profile 408 based on the throttle lever angle 410 using any combination of the low spool motor 12A, high spool motor 12B, and fuel burn” as pointed out in par. 53, bottom; thus the high spool motor can operate with or without the low spool motor and without fuel burn in a no fuel mode because of the instant “any combination” feature; the flight mode can include “descent” for example as pointed out in par. 47, middle wherein one of two engines 100A,100B of aircraft 10 is in a no fuel mode and operated using the low and/or high motors 12A,12B to provide thrust 412 (see fig. 5) wherein such aircraft engines 100A,100A refer to instant engine 100 as discussed in par. 35, top; such a flight mode can include flight idle also discussed in par. 50, middle) while the controller 256 does not command fuel flow (see par. 50) to the combustor 56 and the gas turbine engine 100 is operating in a no fuel mode (see par. 50 and block 604 in fig. 6); and
command, responsive to a trigger event (see par. 50: the pilot decides more thrust is necessary and manipulates the ”pilot control” to regulate the throttle lever angle to go to a “climb mode” or a “takeoff mode” for in the scenario of a go-around aborted landing after descent), fuel flow to the combustor 56 to cause the gas turbine engine 100 to start to a fuel-burning mode (see “any combination” feature in par. 53, bottom), wherein the trigger event is a determination that a requested thrust exceeds an amount of thrust that the gas turbine engine can deliver while operating the gas turbine engine in the electrically powered in flight mode while the controller does not command fuel flow to the combustor and the gas turbine engine is operating in the no fuel mode. While operating in the engine 100 in the electrically powered in flight mode discussed in par. 47 for example during a “descent” the pilot can decide more thrust is necessary and that a fuel burning mode is necessary. Hiett is evidence that a fuel burning mode results in more thrust than an electrically power mode; see pars. 76 and 77 wherein there is a transition from an electrically powered mode to a fuel burning mode when higher thrust is necessary. In addition Shang is evidence (see par. 62, bottom) that a go-around requires maximum power and thus would require the fuel burning mode).
Terwilliger does not disclose the relight is a quick relight.
Hiett teaches a quick relight (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL; “holding” for quick relight is confirmed by fig. 8 wherein the relight occurs at 30 seconds after in-flight shutdown 210 wherein high spool motor and low speed motor supplies power4 to high pressure spool and the low pressure spool (see line 208) wherein the relight at 30 seconds occurred at about 28% speed; fig. 10 shows high speed spool 204 held at about 28% speed from time = 40 seconds to time = 200 seconds and thus the claimed “maintaining” feature is met).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Terwilliger with the relight is a quick relight as taught by Hiett in order to facilitate safe continuation of aircraft flight in the scenario of an inadvertent shutdown (see Hiett par. 27).
Regarding claim 11, Terwilliger discloses (see figs. 1-3 and 6) a method for a hybrid electric single engine (engine 100 of multiengine 100A,100B aircraft 10, wherein such aircraft engines 100A,100A refer to instant engine 100 as discussed in par. 35, top) descent (see par. 50) restart (see par. 51) comprising:
controlling a high spool motor 12B of an aircraft 10 to cause the high spool motor 12B to drive rotation of a high speed spool 32 of a gas turbine engine 100 of the aircraft 10 to maintain a desired compressor pressure (sufficient compression, i.e., sufficient pressure of air compressed by the high pressure compressor 52 for ignition in the combustor 56; see par. 45, middle) and a desired flow (there is a flow corresponding with the desired pressure and this is evidenced by Hiett; Hiett points out regulating the speed of the HP compressor provides sufficient flow into the combustor (see par. 28) to facilitate a relighting (see par. 79); in addition the desired flow through the combustor when the fuel flow is off provides sufficient cooling (see par. 85) to the turbine (air goes through combustor 40 and turbines (36, 42) to cool the turbines resulting in lower EGT’s during restart that makes the restart attempt more reliable (see par. 83))) within a combustor 56, wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts (see par. 45: “using the high spool motor 12B to control the high speed spool 32 to provide sufficient compression in the gas turbine engine 20 for light off in the combustor 56”; and see par. 51: “The starting operation can be… an in-flight restart”) including relights (see par. 51), and wherein the high spool motor is controlled to maintain the high spool speed for restart/relight5 (see pars. 45 and 51; the claim does not specify an amount of time regarding the holding and maintaining; thus Terwilliger meets the claim because maintains the high motor sufficiently for restart and relight), of the gas turbine engine in order to provide thrust while operating the gas turbine engine in an electrically powered in flight mode (such a flight mode is shown at block 604 in fig. 6 wherein the high spool motor 12B is operated in parallel with the low speed motor 12A for (1) engine starting to a fuel burn mode or (2) during other scenarios wherein “The controller 256 can be configured to control a thrust response of the gas turbine engine 20 to a response profile 408 based on the throttle lever angle 410 using any combination of the low spool motor 12A, high spool motor 12B, and fuel burn” as pointed out in par. 53, bottom; thus the high spool motor can operate with or without the low spool motor and without fuel burn in a no fuel mode because of the instant “any combination” feature; the flight mode can include “descent” for example as pointed out in par. 47, middle wherein one of two engines 100A,100B of aircraft 10 is in a no fuel mode and operated using the low and/or high motors 12A,12B to provide thrust 412 (see fig. 5) wherein such aircraft engines 100A,100A refer to instant engine 100 as discussed in par. 35, top; such a flight mode can include flight idle also discussed in par. 50, middle) while a controller 256 does not command fuel flow to the combustor 56 and the gas turbine engine is operating in a no fuel mode (see par. 50); and
commanding fuel flow (see “any combination” feature in par. 53, bottom) to the combustor 56 responsive to a trigger event (see par. 50: the pilot decides more thrust is necessary and manipulates the ”pilot control” to regulate the throttle lever angle to go to a “climb mode” or a “takeoff mode” in the scenario of a go-around aborted landing after descent) to cause the gas turbine engine 100 to start to a fuel-burning mode (see “any combination” feature in par. 53, bottom), wherein the trigger event is a determination that a requested thrust exceeds an amount of thrust that the gas turbine engine can deliver while operating the gas turbine engine in the electrically powered in flight mode while the controller does not command fuel flow to the combustor and the gas turbine engine is operating in the no fuel mode. While operating in the engine 100 in the electrically powered in flight mode discussed in par. 47 for example during a “descent” the pilot can decide more thrust is necessary and that a fuel burning mode is necessary. Hiett is evidence that a fuel burning mode results in more thrust than an electrically power mode; see pars. 76 and 77 wherein there is a transition from an electrically powered mode to a fuel burning mode when higher thrust is necessary. In addition Shang is evidence (see par. 62, bottom) that a go-around requires maximum power and thus would require the fuel burning mode). Terwilliger does not disclose the relight is a quick relight.
Hiett teaches a quick relight (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Terwilliger with the relight is a quick relight as taught by Hiett in order to facilitate safe continuation of aircraft flight in the scenario of an inadvertent shutdown (see Hiett par. 27).
Regarding claim 2, Terwilliger in view of Hiett teach the current invention as claimed and discussed above. Terwilliger discloses (see fig. 2) a low spool motor 12A configured to augment rotational power (see abstract) of the low speed spool 30, wherein the controller 256 is configured (see par. 50, top) to control the low spool motor 12A to drive rotation of the low speed spool 30.
Regarding claim 3, Terwilliger in view of Hiett teach the current invention as claimed and discussed above. Terwilliger discloses (see fig. 2) a low spool generator 213A configured to extract power (see par. 35, bottom) from the low speed spool 30; and a high spool generator 213B configured to extract power (see par. 35, bottom) from the high speed spool 32.
Regarding claims 4 and 14, Terwilliger discloses the current invention as claimed and discussed. Terwilliger does not disclose wherein the controller is configured to selectively provide or providing electrical power from either of the low spool generator) or the high spool generator to a motor of another engine to provide thrust and restart capability to the other engine 200.
Hiett teaches embodiment fig. 3 teaches the controller 116 is configured to selectively provide or providing electrical power from either of the low spool generator 102B or the high spool generator to a motor 102A of another engine 30A to provide thrust and restart capability 204,218 to the other engine 30A. Hiett states in par. 64 that “the second electric machine 102B may extract power from the low pressure system of the second turbomachine 30B and … provide power to the low pressure system of the first turbomachine 30A” and par. 74 points out that the instant provided power may be provided to an electric machine of the other engine (i.e. “separate engine”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Terwilliger with the controller is configured to selectively provide or providing electrical power from the high spool generator to a motor of another engine to provide thrust and restart capability to the other engine as taught by Hiett in order to facilitate in-flight restart when energy storage device (i.e. battery) is depleted (Hiett par. 72).
Regarding claims 10 and 20, Terwilliger discloses the current invention as claimed and discussed above. Terwilliger does not explicitly disclose wherein the desired compressor pressure is determined based on a sensed pressure, and wherein the desired flow is determined based on modeling a plurality of parameters about the gas turbine engine.
Hiett teaches (see fig. 2) a gas turbine 10 and further (see par. 54) teaches a compressor pressure is determined based on a sensed pressure (sensors 114b and/or 114C). Sensor 114B measures a parameter of the high pressure system that includes the high pressure compressor 34 just upstream of the combustor 40. The top portion of par. 54 points out that the parameters of the high pressure system may be “pressures”. Thus Hiett teaches measuring a compressor pressure related to the desired compressor pressure for combustion of Terwilliger regarding the claims 1 and 11 analyses above.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Terwilliger with the desired compressor pressure is determined based on a sensed pressure as taught by Hiett in order to facilitate storing the desired compressor pressure with an engine controller for reliable starting using software (see Hiett par. 56 bottom).
Hiett further teaches (see figs. 4, 5 and 7-10) a desired flow (a desired flow within the combustor i.e. regulating the speed of the HP compressor provides sufficient flow into the combustor (see par. 28) to facilitate a relighting of the engine) is determined based on modeling a plurality of parameters about the gas turbine engine (the desired flow is based on adding power 204; adding power includes modeling (see for example plots in figs. 5 and 8-10) of altitude (i.e. “30kft”), amount of power (i.e., “hp”), airspeed (i.e., “knots”), and duration of applied power before relight (i.e. “time” or e.g. “30s”); also see “exhaust gas temperature” (fig. 7).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Terwilliger in view of Hiett with wherein the desired flow is determined based on modeling a plurality of parameters about the gas turbine engine as taught by Hiett in order to facilitate improvement of the hybrid electric gas turbine of Terwilliger in view of Hiett (see Hiett par. 4).
Regarding claim 12, Terwilliger in view of Hiett teach the current invention as claimed and discussed above. Terwilliger discloses (see fig. 1-3) controlling (with controller 256) a low spool motor 12A to augment rotational power (see abstract) of a low speed spool 30 of the gas turbine engine 100 of the aircraft 20, wherein the low spool motor 12A drives rotation of the low speed spool 30.
Regarding claim 13, Terwilliger in view of Hiett teach the current invention as claimed and discussed above. Terwilliger discloses (see fig. 2) providing a low spool generator 213A configured to extract power (see par. 35, bottom) from the low speed spool 30; and providing a high spool generator 213B configured to extract power (see par. 35, bottom) from the high speed spool 32.
Claim(s) 3, 4, 13 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hiett as evidenced by Lieuwen, Terwilliger, Hayama and Burns.
Regarding claim 3, Hiett discloses (see fig. 1) a high spool generator (see par. 78; electric motor/generator) configured to extract power (a generator extracts power from its corresponding spool) from the high speed spool. Hiett embodiment fig. 1 does not disclose a low spool generator configured to extract power from the low speed spool.
Hiett teaches a low speed generator configured to extract power from the low speed spool (par. 78 discussed a low speed spool electric motor/generator separate from the low speed motor 102A).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Hiett embodiment fig. 1 with a low spool generator configured to extract power from the low speed spool as taught by Hiett in order to facilitate providing additional electrical power to the aircraft.
Regarding claims 4 and 14, Hiett discloses the current invention as claimed and discussed. Hiett embodiment fig. 1 does not explicitly disclose wherein the controller is configured to selectively provide or providing electrical power from either of the low spool generator or the high spool generator to a motor of another engine to provide thrust and restart capability to the other engine 200.
Hiett teaches embodiment fig. 3 teaches the controller 116 is configured to selectively provide or providing electrical power from either of the low spool generator 102B or the high spool generator to a motor 102A of another engine 30A to provide thrust and restart capability 204,218 to the other engine 30A. Hiett states in par. 64 that “the second electric machine 102B may extract power from the low pressure system of the second turbomachine 30B and … provide power to the low pressure system of the first turbomachine 30A” and par. 74 points out that the instant provided power may be provided to an electric machine of the other engine (i.e. “separate engine”).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Hiett embodiment fig. 1 with the controller is configured to selectively provide or providing electrical power from the high spool generator to a motor of another engine to provide thrust and restart capability to the other engine as taught by Hiett in order to facilitate in-flight restart when energy storage device (i.e. battery) is depleted (Hiett par. 72).
Regarding claim 13, Hiett discloses (see fig. 1) providing a high spool generator (see par. 78; electric motor/generator) configured to extract power (a generator extracts power from its corresponding spool) from the high speed spool. Hiett embodiment fig. 1 does not disclose providing a low spool generator configured to extract power from the low speed spool.
Hiett teaches providing a low speed generator configured to extract power from the low speed spool (par. 78 discussed a low speed spool electric motor/generator separate from the low speed motor 102A).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Hiett embodiment fig. 1 with providing a low spool generator configured to extract power from the low speed spool as taught by Hiett in order to facilitate providing additional electrical power to the aircraft.
Response to Arguments
Applicant's arguments filed 06/02/2026 have been fully considered but they are not persuasive.
It is thought that it may be helpful to discuss the interpretation of the newly amended limitations before going into detail regarding applicant’s specific arguments. Regarding “holding the gas turbine engine in a condition to facilitate in-flight restarts including quick relights”, a “condition” can communicate “a mode or state of being” (https://www.thefreedictionary.com/condition). Thus a condition that is conducive to restarting the gas turbine engine quickly would satisfy the claim. The claim does specify the particular condition such as an rpm or an engine thrust level. For example as long as the flow through the high speed spool components makes a restart “less difficult” compared to a scenario without the use of the high speed motor then this appears to satisfy the claim language (facilitate can be interpreted as “to make easier or less difficult”; https://www.thefreedictionary.com/facilitate). However prior art Hiett (Pub. No.: US 2022/0063826 A1) is more detailed in that Hiett specifically holds the high speed spool and the low speed spool at a speed sufficient for light-off within 30 seconds of an in-flight shutdown as shown in annotated fig. 8 below (see line 208) and this is discussed in more detail in the 102 section above.
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Regarding “maintain high spool speed of the gas turbine engine for restart/relight” this is a similar limitation. The claim does not require maintaining a specific RPM value of the high spool nor a specific power level value of the high spool motor or a specific thrust level value of the engine or an amount of time the maintaining must be continued. Thus it appears a maintaining of the high speed spool that is sufficient to restart/relight the engine would satisfy the claim. Hiett specifically maintains the high speed spool RPM at 28% of full speed for over 100 seconds as shown by line 204 in fig. 10 wherein 28% speed is sufficient for light off at pointed out by annotated fig. 10 below.
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In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., hold or maintain the gas turbine engine in a relight-ready condition) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant argues that Terwilliger (Pub. No.: US 2021/0025339 A1) does not disclose "wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts including quick relights, and wherein the controller controls the high spool motor to maintain high spool speed of the gas turbine engine for restart/relight." In response Terwilliger discloses wherein the desired flow provides for holding the gas turbine engine in a condition to facilitate in-flight restarts including relights wherein the desired flow (that flow resulting from the “sufficient compression” discussed in par. 45) provides for holding the gas turbine engine in a condition to facilitate in-flight restarts (see par. 45: “using the high spool motor 12B to control the high speed spool 32 to provide sufficient compression in the gas turbine engine 20 for light off in the combustor 56”; and see par. 51: “The starting operation can be… an in-flight restart”) including relights (see par. 51), and wherein the controller controls the high spool motor to maintain the high spool speed of the gas turbine engine for restart/relight6 (see pars. 45 and 51; the claim does not specify an amount of time regarding the holding and maintaining; thus Terwilliger meets the claim because maintains the high motor sufficiently for restart and relight). For example in fig. 6 before the restart command at block 610 occurs steps 602,604,606 occur. Terwilliger points out in par. 53 that “Control of the high spool motor 12B of block 612 can occur in parallel with control of the low spool motor 12A of block 604 or blocks 604 and 612. This parallel operation can further happen during a “descent” mode as pointed out in Terwilliger par. 50 (this is similar to applicant descent mode in applicant par. 65 and par. 67) . Because the high spool motor is operated before the start command 610 then such motor maintains for an amount of time the high speed spool speed for restart/relight at block 610 and similarly the gas turbine engine flow would facilitate an in-flight restart. In other words use of the high spool motor makes the restart less difficult because the high spool compressor is already rotating and compressing air sufficiently for restart.
However Terwilliger does not disclose that a “quick” relight is facilitated (i.e. a relight can occur very soon after engine shutdown). This is taught by Hiett (Pub. No.: US 2022/0063826 A1). Hiett teaches a quick relight (adding power with the high speed spool after an in-flight shutdown immediately and adding the power until the restart is initiated, see par. 75, wherein the adding power is from the high spool, see par. 72; this can be a quick re-light because the restart/relight may be initiated within 10 seconds from shutdown, see par. 76; Lieuwen is evidence that quick relights are within 1 minute from shutdown, see p. 15 at near bottom of NPL). Therefore because the relight of Terwilliger in view of Hiett happens within 10 seconds from shutdown then the quick relight limitation is met. Hiett provides specific relight related scenarios in figs. 8 and 10 as pointed out above in this section.
Applicant argues that Terwilliger’s no-fuel thrust operations are limited to using only the low spool motor. In response as pointed out above use of the high spool motor can begin at block 602 of fig. 6. In further discussion the method of fig. 6 Terwilliger points out “The controller 256 can be configured to control a thrust response of the gas turbine engine 20 to a response profile 408 based on the throttle lever angle 410 using any combination of the low spool motor 12A, high spool motor 12B, and fuel burn.” Thus one of ordinary skill in the art would understand that parallel operation of both the low spool motor and the high spool motor can happen before the restart to facilitate the restart and hold the gas turbine engine for restart.
Applicant argues against Hiett because Hiett is concerned with reducing speed decay and this is not relevant to the claimed holding the gas turbine in a condition for restarts including relights and maintaining the high speed spool for restart. In Hiett’s reduction of speed decay keeps the low and high pressure compressors rotating at speeds sufficient for restart/relight as shown in figs. 8 and 10 and discussed above. Thus the reduction in speed decay is what makes a quick relight possible. Applicant argues that Hiett does not disclose maintain the high speed spool for restart. As pointed out above in fig. 10 the high speed spool is maintained at 28% speed for over 100 seconds thus maintaining the compressed air flow from the high pressure compressor sufficient for restart (fig. 8 shows 28% sufficient for restart).
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., “reducing the time before re-ignition”) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification and applicant arguments are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant argues Hiett does not disclose desired flow and desired compressor pressure. The flow and compressor pressure of Hiett are desirable because a quick relight is made possible by such flow and pressure as shown in fig. 8. For example there is a minimum pressure required to restart a gas turbine as pointed out by Terwilliger (Terwilliger points out in pars. 44 and 45: “In engine start …, the high spool motor … can be used to increase the speed of the high speed spool … for light off” and “ using the high spool motor … to control the high speed spool … to provide sufficient compression in the gas turbine engine … for light off in the combustor”).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARC J AMAR whose telephone number is (571)272-9948. The examiner can normally be reached M-F 9:00-6:00.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Devon Kramer can be reached at (571) 272-7118. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MARC AMAR/Examiner, Art Unit 3741 /DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741
1 This power rotates the high pressure compressor and low pressure compressor that creates the claimed “desired flow”.
2 One of ordinary skill in the art would understand “relight” to communicate a type of restarting the gas turbine engine that has been unintentionally shut down by flameout. Other types of restart of a gas turbine engine is a cold restart that is a restart after the gas turbine engine components have cooled to ambient temperatures (see US 20190017441 A1 par. 50). A quick relight is usually described as happening within a certain amount of time from engine shutdown as discussed in NPL Lieuwen cited above.
3 One of ordinary skill in the art would understand “relight” to communicate a type of restarting the gas turbine engine that has been unintentionally shut down by flameout. Other types of restart of a gas turbine engine is a cold restart that is a restart after the gas turbine engine components have cooled to ambient temperatures (see US 20190017441 A1 par. 50). A quick relight is usually described as happening within a certain amount of time from engine shutdown as discussed in NPL Lieuwen cited above.
4 This power rotates the high pressure compressor and low pressure compressor that creates the claimed “desired flow”.
5 One of ordinary skill in the art would understand “relight” to communicate a type of restarting the gas turbine engine that has been unintentionally shut down by flameout. Other types of restart of a gas turbine engine is a cold restart that is a restart after the gas turbine engine components have cooled to ambient temperatures (see US 20190017441 A1 par. 50). A quick relight is usually described as happening within a certain amount of time from engine shutdown as discussed in NPL Lieuwen cited above.
6 One of ordinary skill in the art would understand “relight” to communicate a type of restarting the gas turbine engine that has been unintentionally shut down by flameout. Other types of restart of a gas turbine engine is a cold restart that is a restart after the gas turbine engine components have cooled to ambient temperatures (see US 20190017441 A1 par. 50). A quick relight is usually described as happening within a certain amount of time from engine shutdown as discussed in NPL Lieuwen cited above.
Prosecution Insights