Prosecution Insights
Last updated: April 18, 2026
Application No. 19/362,542

GAS TURBINE ENGINE HAVING COMPOSITE FAN BLADES

Non-Final OA §DP
Filed
Oct 20, 2025
Examiner
HUNTER, JOHN S
Art Unit
3761
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
General Electric Company
OA Round
2 (Non-Final)
82%
Grant Probability
Favorable
2-3
OA Rounds
2y 7m
To Grant
99%
With Interview

Examiner Intelligence

Grants 82% — above average
82%
Career Allow Rate
296 granted / 360 resolved
+12.2% vs TC avg
Strong +24% interview lift
Without
With
+24.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 7m
Avg Prosecution
25 currently pending
Career history
385
Total Applications
across all art units

Statute-Specific Performance

§101
3.1%
-36.9% vs TC avg
§103
34.6%
-5.4% vs TC avg
§102
29.6%
-10.4% vs TC avg
§112
28.0%
-12.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 360 resolved cases

Office Action

§DP
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 . Response to Amendment The amendment and/or arguments submitted on 03/26/2026 is/are being considered by the examiner. Claims 1-4, 9-14, 17, 19-22 are pending: Claims 5-8, 15-16, 18 are canceled Claims 21-22 are new Response to Arguments Applicant’s arguments and/or amendments, with respect to Double Patenting have been fully considered and are persuasive. The Double Patenting of record has been withdrawn. The office notes that grounds of nonstatutory Double Patenting are provided below. Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claim 1, 4, 12, 13, 17, 19, 20 rejected on the ground of nonstatutory double patenting as being unpatentable over claim 9, 9, 20, 20, 20, 20, 20, respectively of U.S. Patent No. 12,473,863 in view of Niergarth (US 10,533,436). Although the claims are not identical, they are not patentably distinct from one another. The application claims are broader in at least one aspect and also recite additional features not claimed in the patent claims. Please see the comparison table below, underlined terms indicate element(s) not found in the other document. Instant Application 19/362,542 US Patent 12,473,863 Claim 1 Claim 9 (1+9) A gas turbine engine defining a radial direction, the gas turbine engine comprising: a turbomachine comprising a drive turbine and defining a working gas flowpath and an inlet to the working gas flowpath; a fan having a fan blade formed of a composite material, the fan blade defining a leading edge fan radius RFanLE and a trailing edge fan radius RFan_TE, and the fan defining a leading edge hub radius RHub_LE and a trailing edge hub radius RHub_TE, the gas turbine engine defining a bypass ratio equal to a mass flowrate of an airflow from the fan over the turbomachine to a mass flowrate of an airflow from the fan through the inlet to the working gas flowpath during operation of the gas turbine engine in a cruise operating mode, the bypass ratio being greater than or equal to 10 and less than or equal to 100; an outer nacelle at least partially surrounding the fan; and a reduction gearbox mechanically coupling the drive turbine of the turbomachine to the fan, the reduction gearbox defining a gear ratio greater than or equal to 2 and less than or equal to 4; wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Compression Factor (FLTCF) greater than or equal to 1.05 and less than or equal to 1.8, the FLTCF being equal to: PNG media_image1.png 54 124 media_image1.png Greyscale Claim 1. A gas turbine engine defining a radial direction, the gas turbine engine comprising: a turbomachine comprising a drive turbine and defining a working gas flowpath and an inlet to the working gas flowpath; a fan having a fan blade formed of a composite material, the fan blade defining a leading edge fan radius RFan_LE and a trailing edge fan radius RFan_TE, and the fan defining a leading edge hub radius RHub_LE and a trailing edge hub radius RHub_TE, the gas turbine engine defining a bypass ratio equal to a mass flowrate of an airflow from the fan over the turbomachine to a mass flowrate of an airflow from the fan through the inlet to the working gas flowpath during operation of the gas turbine engine in a cruise operating mode, the bypass ratio being greater than or equal to 10 and less than or equal to 100; and a reduction gearbox mechanically coupling the drive turbine of the turbomachine to the fan; wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Compression Factor (FLTCF) greater than or equal to 1.05 and less than or equal to 1.8, the FLTCF being equal to: PNG media_image1.png 54 124 media_image1.png Greyscale Claim 9. The gas turbine engine of claim 1, wherein the leading edge fan radius RFan_LE is greater than or equal to 35 inches and less than or equal to 50 inches, wherein the fan defines a fan blade count greater than or equal to 12 and less than or equal to 23, and wherein the reduction gearbox defines a gear ratio between 2:1 and 4:1. Claim 4 Claim 9 The gas turbine engine of claim 1, wherein the turbomachine comprises a compressor section having a low pressure compressor and a high pressure compressor, wherein the low pressure compressor is rotatable with the drive turbine. (See quotation above – not repeated in the interest of readability. Same underlining as shown above.) Claim 12 Claim 20 (12+19+20) A gas turbine engine defining a radial direction, the gas turbine engine comprising: a turbomachine comprising a drive turbine and defining a working gas flowpath and an inlet to the working gas flowpath; an unducted fan having a fan blade formed of a composite material, the fan blade defining a leading edge fan radius RFanLE and a trailing edge fan radius RFanTE, and the fandefining a leading edge hub radius RHUb_LE and a trailing edge hub radius RHUb_TE, the gas turbine engine defining a bypass ratio equal to a mass flowrate of an airflow from the fan over the turbomachine to a mass flowrate of an airflow from the fan through the inlet to the working gas flowpath during operation of the gas turbine engine in a cruise operating mode, the bypass ratio being greater than or equal to 10 and less than or equal to 100; and a reduction gearbox mechanically coupling the drive turbine of the turbomachine to the fan, wherein the reduction gearbox defines a gear ratio greater than 2 and less than 14; wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Opening Ratio (FLTOR) greater than or equal to 1.03 and less than or equal to 1.5, the FLTOR being equal to: PNG media_image2.png 52 122 media_image2.png Greyscale Claim 12 A gas turbine engine defining a radial direction, the gas turbine engine comprising: a turbomachine comprising a drive turbine and defining a working gas flowpath and an inlet to the working gas flowpath; a fan having a fan blade formed of a composite material, the fan blade defining a leadingedge fan radius RFan_LE and a trailing edge fan radius RFan_TE, and the fan defining a leading edge hub radius RHub_LE and a trailing edge hub radius RHub_TE, the gas turbine engine defining a bypass ratio equal to a mass flowrate of an airflow from the fan over the turbomachine to a mass flowrate of an airflow from the fan through the inlet to the working gas flowpath during operation of the gas turbine engine in a cruise operating mode, the bypass ratio being greater than or equal to 10 and less than or equal to 100; and a reduction gearbox mechanically coupling the drive turbine of the turbomachine to the fan; wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Opening Ratio (FLTOR) greater than or equal to 1.03 and less than or equal to 1.5, the FLTOR being equal to: PNG media_image2.png 52 122 media_image2.png Greyscale Claim 19 The gas turbine engine of claim 12, wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Compression Factor (FLTCF) greater than or equal to 1.05 and less than or equal to 1.8, the FLTCF being equal to: PNG media_image1.png 54 124 media_image1.png Greyscale Claim 20 The gas turbine engine of claim 19, wherein the fan is an unducted fan, wherein the leading edge fan radius RFan_LE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, wherein the reduction gearbox defines a gear ratio greater than 4 and less than 12, wherein a thrust rating for the gas turbine engine is between 20,000 pounds and 45,000 pounds, wherein the FLTCF is greater than or equal to 1.07 and less than or equal to 1.25, and wherein the FLTOR is greater than or equal to 1.03 and less than or equal to 1.12. Claim 13 Claim 20 (12+19+20) The gas turbine engine of claim 12, wherein the FLTOR is greater than or equal to 1.05 and less than or equal to 1.3. Claim 12/19 recitations not repeated in the interest of readability. Claim 20 The gas turbine engine of claim 19, wherein the fan is an unducted fan, wherein the leading edge fan radius RFan_LE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, wherein the reduction gearbox defines a gear ratio greater than 4 and less than 12, wherein a thrust rating for the gas turbine engine is between 20,000 pounds and 45,000 pounds, wherein the FLTCF is greater than or equal to 1.07 and less than or equal to 1.25, and wherein the FLTOR is greater than or equal to 1.03 and less than or equal to 1.12. Claim 17 Claim 20 (12+19+20) The gas turbine engine of claim 12, wherein the leading edge fan radius RFan LE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, and wherein the FLTOR is greater than or equal to 1.05 and less than or equal to 1.2. Claim 12/19 recitations not repeated in the interest of readability. Claim 20 The gas turbine engine of claim 19, wherein the fan is an unducted fan, wherein the leading edge fan radius RFan_LE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, wherein the reduction gearbox defines a gear ratio greater than 4 and less than 12, wherein a thrust rating for the gas turbine engine is between 20,000 pounds and 45,000 pounds, wherein the FLTCF is greater than or equal to 1.07 and less than or equal to 1.25, and wherein the FLTOR is greater than or equal to 1.03 and less than or equal to 1.12. Claim 19 Claim 20 (12+19+20) The gas turbine engine of claim 12, wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Compression Factor (FLTCF) greater than or equal to 1.05 and less than or equal to 1.8, the FLTCF being equal to: PNG media_image1.png 54 124 media_image1.png Greyscale Claim 12/20 recitations not repeated in the interest of readability. Claim 19 The gas turbine engine of claim 12, wherein the gas turbine engine defines a Fan Leading Edge to Trailing Edge Compression Factor (FLTCF) greater than or equal to 1.05 and less than or equal to 1.8, the FLTCF being equal to: PNG media_image1.png 54 124 media_image1.png Greyscale Claim 20 Claim 20 (12+19+20) The gas turbine engine of claim 19, wherein the fan is an unducted fan, wherein the leading edge fan radius RFanLE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, wherein the reduction gearbox defines a gear ratio is greater than 4 and less than 12, wherein a thrust rating for the gas turbine engine is between 20,000 pounds and 45,000 pounds, wherein the FLTCF is greater than or equal to 1.07 and less than or equal to 1.25, and wherein the FLTOR is greater than or equal to 1.03 and less than or equal to 1.12. Claim 12/19 recitations not repeated in the interest of readability. Claim 20 The gas turbine engine of claim 19, wherein the fan is an unducted fan, wherein the leading edge fan radius RFan_LE is greater than or equal to 65 inches and less than or equal to 85 inches, wherein the fan defines a fan blade count greater than or equal to 5 and less than or equal to 15, wherein the reduction gearbox defines a gear ratio greater than 4 and less than 12, wherein a thrust rating for the gas turbine engine is between 20,000 pounds and 45,000 pounds, wherein the FLTCF is greater than or equal to 1.07 and less than or equal to 1.25, and wherein the FLTOR is greater than or equal to 1.03 and less than or equal to 1.12. Instant Claim 1 The applied US Patent Claim 9 is silent to “an outer nacelle at least partially surrounding the fan”. Niergarth teaches (best seen Fig1; C4L4-7) that it is known in the art to arrange engine 10 as a ducted arrangement where nacelle 50 is present, however Niergarth explicitly teaches that ducted and unducted fan engine arrangements are known in the art alternatives. It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to look to the prior art to select either of a ducted/unducted fan arrangement for the engine of the applied US Patent Claim 9, as one of ordinary skill in the art would have to make such a selection to the arrangement of the nacelle in order to practice the disclosure of applied US Patent Claim 9, and thus it would be obvious for one of ordinary skill in the art to select a ducted fan engine arrangement with a nacelle as taught by Niergarth, and the resulting arrangement has the reasonable expectation of successfully providing the arrangement of the applied US Patent Claim 9 with a working and known selection of a nacelle for a ducted fan engine arrangement as taught by Niergarth. Instant Claim 4 The modified arrangement of applied US Patent Claim 9 by the teachings of Niergarth does not explicitly disclose “a compressor section having a low pressure compressor and a high pressure compressor, wherein the low pressure compressor is rotatable with the drive turbine.”. The office notes that cited limitations of instant claim 4 are generic structure to a gas turbine engine. Niergarth teaches: (as best seen in Fig1; C3L31-44) “a compressor section (compressor section 22/24) having a low pressure compressor (low pressure compressor 22) and a high pressure compressor (high pressure compressor 24), wherein the low pressure compressor (LPC 22) is rotatable with the drive turbine (LPC 22 is driven by LP shaft 36 which is driven by low pressure turbine 30).” It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to modify modified arrangement of applied US Patent Claim 9 by the teachings of Niergarth to include generic structure of a gas turbine engine in order for the modified arrangement of applied US Patent Claim 9 by the teachings of Niergarth to properly function, and Niergarth teaches the generic structure of a compressor section with a low/high compressor where the LP compressor is driven by the turbine section is known in the art, and the resulting arrangement has the reasonable expectation of successfully providing the modified arrangement of the applied US Patent Claim 9 by the teachings of Niergarth with a working and known selection generic gas turbine structure of the compressor section and associated drive shaft from the turbine section. Instant Claim 12 The applied US Patent Claim 20 discloses that the reduction gearbox ratio is “greater than 4 and less than 12” which anticipates instant Claim 12 reduction gearbox ratio of “greater than 2 and less than 14”. Instant Claim 12 The applied US Patent Claim 20 discloses that the FLTOR is “greater than or equal to 1.03 and less than or equal to 1.12” which anticipates instant Claim 13 FLTOR range of “greater than or equal to 1.05 and less than or equal to 1.3”. Instant Claim 17 The applied US Patent Claim 20 discloses that the FLTOR is “greater than or equal to 1.03 and less than or equal to 1.12” which has significant patentable overlap to instant Claim 13 FLTOR range of “greater than or equal to 1.05 and less than or equal to 1.2”. Claim Objections Claims are objected to because of the following informalities: Claim 20 L1-2 amend “wherein the fan is [[an]]the unducted fan” to correct the clear typographical error of improper antecedent basis indication due to the amendment of Claim 12 L5 Claim 21/22 L1 amend “wherein the gear ratio is” to improve clarity by more clearly indicating the antecedent basis from Claim 12 L13 Appropriate correction is required. Allowable Subject Matter The following is a statement of reasons for the indication of allowable subject matter, over art: Claim 1 The prior art of record fails to anticipate or render obvious the limitations of the claim, and in particular the limitations cited below in combination with the remaining limitations of the claim: PNG media_image3.png 128 636 media_image3.png Greyscale Claim 12 The prior art of record fails to anticipate or render obvious the limitations of the claim, and in particular the limitations cited in combination with the remaining limitations of the claim. PNG media_image4.png 130 600 media_image4.png Greyscale The office notes that the above reasons for allowable subject matter over art is the same as in Parent Application 18/909,259 (US Patent 12,473,863) of the Double Patenting rejection of Claim 1/12 as set forth above in this Office action. Claim 2-3, 9-11, 14 would be allowable if rewritten to overcome the rejection(s) under Double Patenting, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims. 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 JOHN HUNTER JR whose telephone number is (571)272-5093. The examiner can normally be reached M-F, 9-18. 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, Helena Kosanovic can be reached at 571 272 9059. 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. /JOHN S HUNTER, JR/Examiner, Art Unit 3761 /HELENA KOSANOVIC/Supervisory Patent Examiner, Art Unit 3761
Read full office action

Prosecution Timeline

Oct 20, 2025
Application Filed
Nov 29, 2025
Non-Final Rejection — §DP
Mar 26, 2026
Response Filed
Mar 31, 2026
Final Rejection — §DP (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

2-3
Expected OA Rounds
82%
Grant Probability
99%
With Interview (+24.2%)
2y 7m
Median Time to Grant
Moderate
PTA Risk
Based on 360 resolved cases by this examiner. Grant probability derived from career allow rate.

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