Notice of Pre-AIA or AIA Status
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 § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 1, 4, 7-9, 12, and 14-19 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels (DE 2020/000055, US patent 11976580 being used as English equivalent) in view of Lear (US-Pub 20190186729).
Regarding claim 1, Klingels a system of suppressing contrails emitted from an aircraft comprising, a recuperator component (12, fig 4) that is positioned within an exhaust gas stream (line from 16 flowing to 12, fig 4) to direct a portion of the exhaust gas stream to one or more heat exchangers (22, fig 4), wherein the heat exchanger is configured to receive parallel streams flowing in opposite directions (air coming from 12 and air coming from 11, fig 4), wherein the parallel streams comprise an ambient air stream ( ambient air comes through the fan section in the same manner as applicants fig 6a) and the portion of the exhaust gas stream output from the upstream heat exchanger (12, fig 4), wherein the one or more heat exchangers in the recirculation path are configured to, before the ambient air stream exits via a fan nozzle (as can be seen in 36, fig 5, as it is not shown in fig 4 for simplicity but the fan duct would have an exit nozzle), heat up the ambient air stream, wherein the heated ambient air stream is no mixed with an exhaust fluid stream (exhaust fluid is output through 25, fig 4) before being output from the one or more heat exchangers to the fan nozzle of the aircraft to provide thrust to the aircraft (the hot air will add to the mass flow rate of air accelerating as it exits the fan nozzle, thus would provide thrust to the aircraft).
Klingels does not disclose a semi-closed cycle gas turbine engine that exhausts gases in use; a recuperator component that removes a portion of the exhaust gas stream to heat combustion air; and direct the portion of the exhaust gas stream to one or more heat exchangers in a recirculation path for the portion of the exhaust gas stream that are configured to heat a secondary fluid to condense the exhaust gas to remove water vapor from the exhaust gas stream before the portion of the exhaust gas stream is recirculated through the semi-closed cycle gas turbine engine.
Lear teaches a system of suppressing water emitted from a gas turbine engine such as the one in Klingels comprising: a semi-closed cycle gas turbine engine (fig 3) that exhausts gases in use; a recuperator (123, fig 3) component that is positioned within an exhaust gas stream (dashed line leaving 116, fig 3) of the semi-closed cycle gas turbine engine to remove a portion of the exhaust gas stream to heat combustion air (the recuperator takes heat from the exhaust gas and delivers it to the compressed air leaving 113, fig 3); and direct the portion of the exhaust gas stream to one or more heat exchangers (133, 136, and 139, fig 3); and the one or more heat exchangers in a recirculation path for the portion of the exhaust gas stream that are configured to heat a secondary fluid to condense the exhaust gas (solid black arrow from 133, fig 3, the exhaust gas is condensed, meaning that the exhaust gas is cooled while the cooling fluid is heated) to remove water vapor from the exhaust gas stream before the portion of the exhaust gas stream is recirculated through the semi-closed cycle gas turbine engine (146, fig 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the gas turbine engine of Klingels by using the semi-closed gas turbine engine with a fresh water refrigeration system such as in Lear. Doing so would allow the system to enhance system efficiency (par. 0007), as suggested by Lear. Furthermore, one of ordinary skill in the art would recognize that recirculating air increases operational stability at lower flow rates.
Regarding claim 4, Klingels discloses wherein the semi-closed cycle gas turbine engine comprises a turbofan jet implementation of the semi-closed cycle gas turbine engine (10 has a fan 11 making it a turbofan engine, fig 4).
Regarding claim 7, Klingels as modified by Lear discloses wherein the semi-closed cycle gas turbine engine comprises a high-pressure compressor (113, fig 3, Lear), a high-pressure turbine (116, fig 3, Lear), and a combustor (119, fig 3, Lear).
Regarding claim 8, Klingels as modified by Lear discloses wherein compressed gas from the high-pressure compressor is provided to the recuperator component (dotted arrow from 113, fig 3, Lear).
Regarding claim 9, Klingels teaches a method of suppressing contrails emitted from an aircraft (col 2, lines 7-13, the water is recovered from the exhaust gas, contrails are formed by water emitted from the exhaust gas, thus the method of removing water of Klingels would suppress contrails) turbine engine (1, fig 4), wherein a heat exchanger (22, fig 4) is configured to receive parallel streams flowing in opposite directions (air coming from fan 11 and exhaust coming from HX 12, fig 4), wherein the parallel streams comprise an ambient air stream (air coming from fan 11, fig 4) and the portion of the exhaust gas stream (stream from 12, fig 4) output from the heat exchanger upstream (12, fig 4), wherein the one or more heat exchangers in the recirculation path are configured to heat up the ambient air stream, and internally storing the liquid water condensed (28, fig 4 is an accumulator) thereby suppressing a formation of contrails emitted from the aircraft via the exhaust gas stream, and direct the ambient air stream through an exit fan nozzle of the aircraft (although not shown for simplicity, the fan duct would have an exit similar to 36, fig 5), by outputting the ambient air stream from the one or more heat exchangers the exit fan nozzle of the aircraft, wherein the heated ambient airstream is not mixed with an exhaust fluid stream (21, fig 4) before being output to the fan nozzle to provide thrust to the aircraft (the hot air will add to the mass flow rate of air accelerating as it exits the fan nozzle, thus would provide thrust to the aircraft).
Klingels does not disclose a semi-closed cycle gas turbine engine; removing, via a recuperator component, a portion of the exhaust gas stream to heat combustion air; receiving, an exhaust gas stream in one or more heat exchangers via a recirculation path from the recuperator and recirculating the removed portion of the exhaust gas stream through the semi-closed cycle gas turbine engine.
Lear teaches a method of removing water from an exhaust comprising: providing a semi-closed cycle gas turbine engine (fig 3) that exhausts gases in use; removing, via a recuperator (123, fig 3) component, a portion of the exhaust gas stream to heat combustion air (recuperators remove heat from exhaust and delivers it to the compressor air flow formed by the dotted line leading from 113); directing the portion of the exhaust gas stream to one or more heat exchangers (133, 136, and 139, fig 3); receiving, via the one or more heat exchangers in a recirculation path (dotted line leading from 123 to 146, fig 3) from the recuperator, the removed exhaust gas stream; condensing the removed exhaust gas stream to form liquid water (cold water, solid black line, fig 3), and recirculating the removed portion of the exhaust gas stream through the semi-closed cycle gas turbine engine (146, fig 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the method of suppressing contrails from a gas turbine engine of Klingels by using the semi-closed gas turbine engine with a freshwater refrigeration system such as in Lear. Doing so would allow the system to enhance system efficiency (par. 0007), as suggested by Lear. Furthermore, one of ordinary skill in the art would recognize that recirculating air increases operational stability at lower flow rates.
Regarding claim 12, Klingels discloses wherein the semi-closed cycle gas turbine engine comprises a turbofan jet implementation of the semi-closed cycle gas turbine engine (10 is a turbofan due to its fan 11, fig 4).
Regarding claim 14, Klingels as modified by Lear discloses wherein the semi-closed cycle gas turbine engine comprises a high-pressure compressor (113, fig 3, Lear), a high-pressure turbine (116, fig 3, Lear), and a combustor (119, fig 3, Lear).
Regarding claim 15, Klingels as modified by Lear discloses directing compressed gas from the high-pressure compressor is provided to the recuperator component (dotted arrow from 113, fig 3, Lear).
Regarding claims 16 and 17, Klingels further discloses the aircraft (3, fig 6).
Regarding claim 18, Klingels as modified by Lear discloses a saturator component (303, fig 3, Lear) in fluidic communication with the high pressure compressor, the one or more heat exchangers, and the recuperator component, wherein input flows to the saturator component comprises fluidic flows from the high pressure compressor and the one or more heat exchangers, wherein an output flow of the saturator component is received by the recuperator component (123, fig 3, Lear).
Regarding claim 19, Klingels as modified by Lear discloses wherein the semi-closed cycle gas turbine engine further comprises a saturator component (303, fig 3, Lear) in fluidic communication with the high pressure compressor, the one or more heat exchangers, and the recuperator component, the method further comprising: directing fluidic flows from the high pressure compressor and the one or more heat exchangers to the saturator component (inlets from 136 and 113, fig 3, Lear); and directing an output flow of the saturator component to the recuperator component (123, fig 3, Lear).
Claims 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Lear in claim 1, further in view of Haugstetter (10773819).
Regarding claims 2 and 3, Klingels discloses a storage tank (28, fig 4) for internally storing liquid water formed from the removed water vapor.
Klingels does not disclose wherein the storage tank comprises a fuel tank of the aircraft having a bladder that separates the liquid water from a fuel source for aircraft.
Haugstetter teaches a storage tank (13, fig 4) for an aircraft (10, fig 1) for internally storing liquid water formed from the removed water vapor (12, fig 4), wherein the storage tank comprises a fuel tank (13, fig 4) of the aircraft having a bladder (14, fig 4) that separates the liquid water from a fuel source for aircraft (the liquid inside 13 is fuel).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the system for using water disclosed by Klingels as modified by Lear by having a water storage system comprising a fuel tank having a bladder that separates the water and fuel based on the teachings of Haugstetter. Doing so would allow for water generated during a flight to be stored for later without needing a dedicated storage space (col 1, lines 15-30), as suggested by Haugstetter.
Claims 5 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Lear in claims 1 and 9, further in view of Kupratis (10337401).
Regarding claims 5 and 13, Klingels as modified by Lear does not disclose wherein the semi-closed cycle gas turbine engine comprises a turbojet implementation of the semi-closed cycle gas turbine engine.
Kupratis teaches wherein a recuperated gas turbine engine similar to Klingels and Lear can be used to drive a turbojet (col 8, lines 29-45) rather than a turbofan.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the engine of Klingels as modified by Lear in a turbojet configuration rather than a turbofan based on the teachings of Kupratis. One of ordinary skill in the art would recognize that the turbojet is more effective in different flight regimes, thus the preferred engine configuration could be chosen based upon intended flight envelopes.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Lear in claim 1, further in view of Hoffjann (8640439).
Regarding claim 6, Klingels as modified by Lear does not disclose wherein the semi-closed cycle gas turbine engine is part of an electrical propulsion system for the aircraft.
Hoffjann teaches using a gas turbine engine (2, fig 2) as part of an electrical propulsion (the electric motor 3 uses the gas turbine engine shaft 7 as a means to drive the propulsor 1, fig 2) system for an aircraft.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the gas turbine engine disclosed by Klingels as modified by Lear by using the gas turbine as part of an electrical propulsion system based on the teachings of Hoffjann. Using a mixed drive system can reduce generated pollutants (col 1, lines 25-30), as suggested by Hoffjann
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Lear as applied to claim 9 above, and further in view of Hoffjann.
Regarding claim 10, Klingels as modified by Lear does not disclose utilizing the stored liquid water as sanitation water for the aircraft.
Hoffjann teaches wherein water on an aircraft used for injection into a combustor can also be used as sanitation water (col 4, lines 15-30).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the water usage disclosed by Klingels as modified by Lear by using the produced water as sanitation water based on the teachings of Hoffjann. Doing so would reduce the amount of water which is carried along (col 4, lines 23-27), as suggested by Hoffjann.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Klingels as modified by Lear as applied to claim 9 above, and further in view of Haugstetter.
Regarding claim 11, Klingels as modified by Lear does not disclose wherein the liquid water is stored in a fuel tank having a bladder separating the liquid water from a fuel source for the aircraft.
Haugstetter teaches a storage tank (13, fig 4) for an aircraft (10, fig 1) for internally storing liquid water formed from removed water vapor (12, fig 4), wherein the storage tank comprises a fuel tank (13, fig 4) of the aircraft having a bladder (14, fig 4) that separates the liquid water from a fuel source for aircraft (the liquid inside 13 is fuel).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the system for using water disclosed by Klingels as modified by Lear by having a water storage system comprising a fuel tank having a bladder that separates the water and fuel based on the teachings of Haugstetter. Doing so would allow for water generated during a flight to be stored for later without needing a dedicated storage space (col 1, lines 15-30), as suggested by Haugstetter.
Response to Arguments
Applicant’s arguments, see remarks, filed 7/14/2026, with respect to the claim objections have been fully considered and are persuasive. The objection of claim 1 has been withdrawn.
Applicant’s arguments, see remarks, filed 7/14/2026, with respect to the rejection(s) of claim(s) 1 and under Lear as modified by Klingels have been fully considered and are persuasive. Therefore, the rejection has been withdrawn in light of the amended claims. However, upon further consideration, a new ground(s) of rejection is made in view of Klingels as modified by Lear.
Conclusion
THIS ACTION IS MADE FINAL. 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 SEAN V MEILLER whose telephone number is (571)272-9229. The examiner can normally be reached 7am-5pm.
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/SEAN V MEILLER/Examiner, Art Unit 3741
/DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741
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