Prosecution Insights
Last updated: April 19, 2026
Application No. 18/532,647

GAS TURBINE ENGINE AND COMBUSTOR THEREFOR

Non-Final OA §102§103
Filed
Dec 07, 2023
Examiner
LIU, JINGCHEN
Art Unit
3741
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
GE Aerospace Poland Sp Z O O
OA Round
4 (Non-Final)
59%
Grant Probability
Moderate
4-5
OA Rounds
2y 7m
To Grant
99%
With Interview

Examiner Intelligence

Grants 59% of resolved cases
59%
Career Allow Rate
51 granted / 87 resolved
-11.4% vs TC avg
Strong +62% interview lift
Without
With
+62.0%
Interview Lift
resolved cases with interview
Typical timeline
2y 7m
Avg Prosecution
33 currently pending
Career history
120
Total Applications
across all art units

Statute-Specific Performance

§101
0.5%
-39.5% vs TC avg
§103
48.1%
+8.1% vs TC avg
§102
14.1%
-25.9% vs TC avg
§112
36.2%
-3.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 87 resolved cases

Office Action

§102 §103
Detailed Action 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 . Continued Examination Under 37 CFR 1.114 A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 11/18/2025 has been entered. Claim Rejections - 35 USC § 102 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 (i.e., changing from AIA to pre-AIA ) 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 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)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claims 1-2, 7-8, 11-14, and 20-21 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by GERENDAS 20130042627. Examiner Note: “a set of cooling holes” is interpreted as cooling holes for cooling combustion liner in the below rejection. Regarding claim 1, GERENDAS teaches the invention as claimed: A combustor (having chamber 7) for a turbine engine (Fig. 1) comprising: a dome wall (5) having a dome wall section (see Fig. 12) including a plate (annotated Fig. 12) and a heat shield (annotated Fig. 12) spaced from the plate to define a cavity (annotated Fig. 12, where the heat shield cooling air flow through), the dome wall section including a seal (annotated Fig. 12, which is the 40 in Fig. 9, see [0055]) positioned between and engaged with the heat shield and the plate to seal the cavity (see annotated Fig. 12 and [0055 and 0058]); a combustor liner (9) extending from the dome wall (5, see Fig. 1); and a combustion chamber (7) at least partially defined by the dome wall (5) and the combustor liner (9, see Fig. 1); wherein the dome wall further includes: a fuel cup (in order to receive injector 6, see Figs. 1-2) disposed at the dome wall section of the dome wall (5), the fuel cup comprising a fuel cup centerline (27, see Figs. 2 and 12); a set of air tubes (17s) extending through the dome wall section to direct air (the damping air) into the combustion chamber (7; see Fig. 12); and a set of cooling holes (25s) extending through the heat shield (annotated Fig. 12) of the dome wall section (see Fig. 12). PNG media_image1.png 924 1135 media_image1.png Greyscale Regarding claim 7, GERENDAS further teaches wherein the set of air tubes comprises at least two air tubes (17s; see Fig. 12). Regarding claim 8, GERENDAS further teaches wherein the heat shield (annotated Fig. 12) includes the set of air tubes (the insert portion of 17s, see annotated Fig. 12); and wherein the set of air tubes (the forward extending portion of 17s, see annotated Fig. 12) extend forward from the heat shield (annotated Fig. 12) toward the plate (annotated Fig. 12). PNG media_image2.png 771 1134 media_image2.png Greyscale Regarding claim 11, GERENDAS further teaches wherein the set of cooling holes (25s, see Figs. 12-13) includes cooling holes disposed radially outward (annotated Fig. 13) of the set of air tubes (annotated Fig. 13) and cooling holes disposed radially inward (annotated Fig. 13) of the set of air tubes (annotated Fig. 13). PNG media_image3.png 752 850 media_image3.png Greyscale Regarding claim 12, GERENDAS further teaches wherein the dome wall (5) comprises a set of impingement holes (16s in Fig. 2 where cooling air, i.e., the solid arrow in Fig. 12, is deflected a few times, which causes impinging, before enters the cavity; also see annotated Fig. 12 and [0043]). PNG media_image4.png 791 1286 media_image4.png Greyscale Regarding claim 13, GERENDAS further teaches wherein the set of impingement holes (16s in Fig. 2 and [0043]) includes impingement holes (the 16s located in the radial outward portion of 5 marked in annotated Fig. 1) disposed radially outward (relative to 27) of the set of air tubes (the 17s located in the radial inward portion of 5 marked in annotated Fig. 1, which is also the 17s in Fig. 12) and impingement holes (the 16s located in the radial inward portion of 5 marked in annotated Fig. 1, which is the 16 marked in annotated Fig. 12 in claim 12) disposed radially inward (relative to 27) of the set of air tubes (the 17s located in the radial outward portion of 5 marked in annotated Fig. 1). PNG media_image5.png 872 1374 media_image5.png Greyscale Regarding claim 14, GERENDAS further teaches wherein the set of impingement holes (16s in Fig. 2 and [0043]) are radially offset from the set of cooling holes (17s, see Fig. 12). Regarding claim 20, GERENDAS further teaches wherein the set of air tubes (17s) includes a plurality of air tubes spaced about the dome wall section (see Figs. 12-13). Regarding claim 21, GERENDAS further teaches wherein the seal (annotated Fig. 12 in claim 1, which is the 40 in Fig. 9, see [0055]) is positioned radially outward of the set of air tubes (17s, see annotated Fig. 12 in claim 1). Examiner Note: “a set of cooling holes” is interpreted as cooling holes for film cooling the heat shield in the below rejection. Regarding claim 1, GERENDAS teaches the invention as claimed: A combustor (having chamber 7) for a turbine engine (Fig. 1) comprising: a dome wall (5) having a dome wall section (see Fig. 12) including a plate (annotated Fig. 12) and a heat shield (annotated Fig. 12) spaced from the plate to define a cavity (annotated Fig. 12, where the heat shield cooling air flow through), the dome wall section including a seal (annotated Fig. 12, which is the 40 in Fig. 9, see [0055]) positioned between and engaged with the heat shield and the plate to seal the cavity (see annotated Fig. 12 and [0055 and 0058]); a combustor liner (9) extending from the dome wall (5, see Fig. 1); and a combustion chamber (7) at least partially defined by the dome wall (5) and the combustor liner (9, see Fig. 1); wherein the dome wall further includes: a fuel cup (in order to receive injector 6, see Figs. 1-2) disposed at the dome wall section of the dome wall (5), the fuel cup comprising a fuel cup centerline (27, see Figs. 2 and 12); a set of air tubes (17s) extending through the dome wall section to direct air (the damping air) into the combustion chamber (7; see Fig. 12); and a set of cooling holes (the cooling cools for film cooling the surface of the heat shield, see [0050]) extending through the heat shield (annotated Fig. 12) of the dome wall section (see Fig. 12). PNG media_image1.png 924 1135 media_image1.png Greyscale Regarding claim 2, GERENDAS further teaches wherein the set of cooling holes (the cooling holes for film cooling the surface of the heat shield, see [0050]) are parallel with (per [0050], the cooling holes are angle to the surface of the heat shield in Fig. 12, and said teaching range includes the situation that the cooling holes are parallel to the centerline 27) the fuel cup centerline (27). 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 (i.e., changing from AIA to pre-AIA ) 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. 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. Claims 1 and 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over RIMMER 20190093892 in view of North 20030000217. Regarding claim 1, RIMMER teaches the invention as claimed: A combustor (15, Fig. 2) for a turbine engine (10, Fig. 1) comprising: a dome wall having a dome wall section (see Figs. 2-3 and [0050]) including a plate (46, Fig. 3) and a heat shield (48 as shown in Figs. 3-4) spaced from the plate (46, see Fig. 3) to define a cavity (47 in Fig. 3); a combustor liner (54 and 50, see Fig. 2) extending from the dome wall (see Fig. 2); and a combustion chamber (annotated Fig. 2) at least partially defined by the dome wall and the combustor liner (see annotated Fig. 2); wherein the dome wall further includes: a fuel cup (60) disposed at the dome wall section of the dome wall (see Figs. 2-4), the fuel cup comprising a fuel cup centerline (the dash-line in Figs. 2-3); a set of air tubes (74s, 76s, 80s, and 78s) extending through the dome wall section to direct air into the combustion chamber (see Figs. 3-4 and [0053]); and a set of cooling holes (the cooling holes to provide a film of cooling air on surface 82, see Fig. 3 and [0055]) extending through the heat shield (48) of the dome wall section (see Fig. 3). PNG media_image6.png 698 996 media_image6.png Greyscale RIMMER does not teach the dome wall section including a seal positioned between and engaged with the heat shield and the plate to seal the cavity. However, North teaches the dome wall section (Fig. 3) including a seal (224 and 222) positioned between (upstream surface 160 of the plate 148 and downstream surface 182 of the heat shield 170, see Fig. 3) and engaged with the heat shield (170) and the plate (148) to seal the cavity (210, see Fig. 3 and [0024 and 0026]). It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify RIMMER with North’s seal positioned between and engaged with the heat shield and the plate to seal the cavity because it is noted that a simple substitution of one known element, in this case, tight contacting the heat shield and the plate to seal a cavity, for another, in this case, placing a seal between the heat shield and the plate to seal a cavity as taught by North, to obtain predictable results, in this case, preventing leaking for the cavity as taught by North, was an obvious extension of prior art teachings, MPEP 2141 III B. Regarding claim 3, RIMMER further teaches wherein the set of air tubes (74s, 76s, 80s, and 78s, see Figs. 3-8 and [0053]) includes one or more air tubes (76s) including a portion having an air tube centerline (annotated Fig. 3) disposed at an oblique angle relative to the fuel cup centerline (see annotated Fig. 3 and [0059]). PNG media_image7.png 737 975 media_image7.png Greyscale Regarding claim 4, RIMMER further teaches wherein the oblique angle is an acute angle (see annotated Fig. 3 in claim 3) such that the one or more air tubes (76s) directs air into the combustion chamber and toward the fuel cup centerline (see annotated Fig. 3 in claim 3). Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over RIMMER 20190093892 in view of North 20030000217, and in further view of Green 20090188255. Regarding claim 5, RIMMER further teaches the one or more air tubes (76s) having an air tube hydraulic diameter (per Fig. 7, 76 is formed with a circular shape, and a hydraulic diameter for a circular tube is equal to the diameter of said circular tube, i.e., the claimed air tube hydraulic diameter is the diameter of 76) that is 3 mm (see [0060]), and at least one cooling hole of the set of cooling holes (one cooling hole of the plurality of cooling holes extends through the heat shield 48 to provide a film of cooling air on a surface 82 facing to the combustion chamber, see [0055] and Fig. 3) having a cooling hole hydraulic diameter (as a physical parameter of the set of cooling holes per [0055]). RIMMER in view of North does not teach said air tube hydraulic diameter is at least two times larger than said cooling hole hydraulic diameter. However, Green teaches at least one cooling hole of the set of cooling holes (a 118 of the 118s, see Fig. 8) that has a cooling hole hydraulic diameter approximately 0.635mm (a hydraulic diameter for a circular tube is equal to the diameter of said circular tube, and per [0031] the diameter of hole 118 is about 0.025 inches, see [0031]). It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the disclosed but non-depicted set of cooling hole of RIMMER in view of North as Green’s set of cooling holes having a cooling hole hydraulic diameter approximately 0.635 mm, such that wherein an air tube hydraulic diameter of the one or more air tubes (3 mm as taught by RIMMER) is at least two times larger than a cooling hole hydraulic diameter of at least one cooling hole of the set of cooling holes (0.635 mm as taught by Green) because the quantity and hole diameter of a set of effusion cooling holes are variable according to the cooling requirement, and a diameter of approximately 0.635 with 4000 holes are able to satisfy such cooling requirement (Green, [0031]). Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over RIMMER 20190093892 in view of North 20030000217 and Green 20090188255, and in further view of Stevens 20190056110. Regarding claim 6, RIMMER further teaches wherein the dome wall section (see Figs. 2-3 and [0050]) includes a fuel inlet (annotated Fig. 2, where the fuel and air enters the combustion chamber via the injector 62, also see [0063]); and wherein the fuel inlet having a fuel inlet hydraulic diameter (a hydraulic diameter of a circular tube is the diameter of said circular tube, i.e., the fuel inlet hydraulic diameter is the diameter of the fuel inlet in annotated Fig. 2), and the air tube hydraulic diameter of the one or more air tubes (76s) is a range from 0.5 mm to 3.5 mm (see [0060]); and a total air flow passing through the one or more air tubes (the total air flow through the plurality of radial inner air tubes 76s and 80s) is in a range from 0.25% to 3% of the total combustor air mass flow to ensure sufficient amount of air to penetrate into the primary combustion zone in order to reduce smoke without disrupting the fuel and air flow field from the fuel inlet (the fuel and air injected by the fuel injector 62, see [0063]). PNG media_image8.png 681 971 media_image8.png Greyscale RIMMER in view of North and Green does not teach said fuel inlet hydraulic diameter is defined by a fuel injector. However, Stevens teaches wherein the dome wall (the wall at the inlet end 101a in Fig. 2) includes a fuel inlet (annotated Fig. 2); and wherein the fuel inlet having a fuel inlet hydraulic diameter (the diameter of the fuel inlet of annotated Fig. 2) that defines by a radial height (Hp in Fig. 5) of a pilot flow passage (172) of the fuel injector (120, see [0072]) and a radial height (the radial height per [0073]) of a main flow passage (200) of the fuel injector; and said two radial heights are sized to ensure a total air flow passing through the pilot flow passage is in a range from 15% to 40% of the total combustor air mass flow and a total air flow passing through the main passage is in a range from 25% to 50% of the total combustor air mass flow (see [0071-0073]) in order to reduce combustion dynamics and reduce NOx emissions ([0075]). PNG media_image9.png 691 896 media_image9.png Greyscale It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the disclosed but non-depicted fuel injector of RIMMER in view of North and Green as Stevens’ fuel injector because the fuel injector as taught by Stevens reduces combustion dynamics and reduces NOx emissions (Stevens, [0075]). RIMMER in view of North, Green and Stevens does not teach said fuel inlet hydraulic diameter is at least twice as large as said air tube hydraulic diameter. However, RIMMER and Stevens as discussed above teaches an air flow split rate between the set of air tube and the fuel inlet is a results-effective variable of a rate between the air tube hydraulic diameter and the fuel inlet hydraulic diameter that controls NOx emissions (see RIMMER’s [0063] and Stevens, [0071-0073 and 0075]). A particular parameter is a result-effective variable when the variable is known to achieve a recognized result. See In re Antonie, 559 F.2d 618, 620, 195 USPQ 6,8 (CCPA 1977). Therefore, an ordinary skilled worker would recognize that the air flow split rate between the set of air tube and the fuel inlet is a results-effective variable of the rate between the air tube hydraulic diameter and the fuel inlet hydraulic diameter that controls NOx emissions. Thus, the claimed limitation of a fuel inlet hydraulic diameter of the fuel inlet is at least twice as large as the air tube hydraulic diameter is found to be an obvious optimization of the prior art obtainable by an ordinary skilled worker through routine experimentation. Further, it appears that one of ordinary skill in the art would have had a reasonable expectation of success in modifying the fuel inlet hydraulic diameter of RIMMER in view of North, Green and Stevens to have the fuel inlet hydraulic diameter of the fuel inlet is at least twice as large as the air tube hydraulic diameter, as it involves only adjusting at least one of the radial height of the pilot air passage, the radial height of the main air passage, and the diameter of the air tube of RIMMER in view of North, Green and Stevens disclosed to require adjustment. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation", In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The presence of a known result-effective variable would be a motivation for a person of ordinary skill in the art to experiment to reach another workable product or process. See KSR; MPEP 2144.05(II)(B). Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of RIMMER in view of North, Green and Stevens wherein a fuel inlet hydraulic diameter of the fuel inlet is at least twice as large as the air tube hydraulic diameter in order to optimize NOx emissions. Response to Arguments Applicant's argument filed 11/18/2025 has been fully considered but the argument is moot because said argument does not applied to i) the new reference; and ii) the new combination of the previously applied reference and the new reference being used in the current Office Action, necessitated by amendment. However, to the extent possible, Applicant's argument has been addressed above, at the appropriate locations. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to JINGCHEN LIU whose telephone number is (571)272-6639. The examiner can normally be reached 9:30-4:30. 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. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /JINGCHEN LIU/ /GERALD L SUNG/ Primary Examiner, Art Unit 3741 Examiner, Art Unit 3741
Read full office action

Prosecution Timeline

Dec 07, 2023
Application Filed
Apr 29, 2025
Non-Final Rejection — §102, §103
Jul 15, 2025
Applicant Interview (Telephonic)
Jul 15, 2025
Examiner Interview Summary
Jul 30, 2025
Response Filed
Sep 03, 2025
Non-Final Rejection — §102, §103
Sep 18, 2025
Final Rejection — §102, §103
Oct 20, 2025
Applicant Interview (Telephonic)
Oct 20, 2025
Examiner Interview Summary
Oct 28, 2025
Response after Non-Final Action
Nov 18, 2025
Request for Continued Examination
Dec 03, 2025
Response after Non-Final Action
Feb 09, 2026
Non-Final Rejection — §102, §103
Apr 07, 2026
Examiner Interview Summary
Apr 07, 2026
Applicant Interview (Telephonic)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12601488
PREMIXER ARRAY
2y 5m to grant Granted Apr 14, 2026
Patent 12601303
ENGINE SYSTEM AND METHOD OF OPERATING THE SAME
2y 5m to grant Granted Apr 14, 2026
Patent 12571536
MULTI-WALLED STRUCTURE FOR A GAS TURBINE ENGINE
2y 5m to grant Granted Mar 10, 2026
Patent 12560123
ARCUATE FUEL GALLERY FOR TURBINE ENGINE FUEL NOZZLE
2y 5m to grant Granted Feb 24, 2026
Patent 12553364
MAGNET ANTI-ICE SYSTEM
2y 5m to grant Granted Feb 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

4-5
Expected OA Rounds
59%
Grant Probability
99%
With Interview (+62.0%)
2y 7m
Median Time to Grant
High
PTA Risk
Based on 87 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month