CTNF 19/274,172 CTNF 93188 DETAILED ACTION Notice of Pre-AIA or AIA Status 07-03-aia AIA 15-10-aia The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA. 07-20-02-aia AIA This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention. Priority The instant application claims foreign priority to IN202311010789 and is a CIP of 19/261563. 19/261563 discloses some information about fan and hub radius in Fig 24 of the application, but the foreign priority document does not. The earliest possible priority date for any claim of this application in 07 July 2025, the filing date of 19/261563. Any claims not supported by 19/261563 have an effective filing date of 18 July 2025, the filing date of this application. Information Disclosure Statement The IDS filed 18 July 2025 was considered, with the exception of the two references crossed out. These references were not at all relevant to gas turbine engines or fan design, relating instead to electronics. US 2020/0077047 was removed. It appears that the correct document is US 2024/0077047, which is listed on the IDS. The correct document for US 10,860,126 could not be confidently determined, but it may be an egregious typo of US 10,760,428, which is pertinent and is listed on the PTO-892. Drawings 06-22 AIA The drawings are objected to because in Fig 24, the text “TRUST” should be corrected to “THRUST” . Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. Specification 07-44 AIA The specification is objected to as failing to provide proper antecedent basis for the claimed subject matter. See 37 CFR 1.75(d)(1) and MPEP § 608.01(o). Correction of the following is required: The specification does not recite the claimed trailing edge ratio of 2.38 to 5.38. Some values can be calculated from the Table in Fig 24, but these have a much narrower range than the claim . Double Patenting 08-37 AIA Claim s 1-20 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claim s 1-20 of copending Application No. 19/261546 in view of US 2023/0392502. 19261546 claims all limitations of claims 1-20, except those concerning the protector and APF, which are taught by Gondre. Gondre teaches: a gas turbine engine fan blade made of a fiber reinforced polymer (¶11) with a titanium alloy metal shield (13, ¶40) on the leading edge. The shield “fins extend over a length greater than or equal to 15% and less than or equal to 25% of a chord length of the airfoil” (¶53). Examiner notes that the claimed APF is defined from the leading edge of the protector (shield), whereas Gondre discloses the % of the composite pressure and suction sidewalls. Nonetheless, the nose portion is generally short in chord length compared to the airfoil and the shield. For example, Fig 1 shows, near the root, that composite blade extends far into the shield. Likewise, Fig 2 shows that the fins 14 are much longer in chord length than the nose 13, as the ends of the fins cannot even be seen at the right side of the drawing. Thus, given that Gondre teaches a range of 15 to 25%, the addition of the chord length of the nose portion would not push all embodiments of Gondre over an APF of 30%. It is both self-evident and known in the art that the surface area of the connection (i.e., the portion of the pressure and suction sides covered) affects the amount of area available for attachment, such as by an adhesive. Likewise, the overall amount of metal affects the stiffness and impact resistance of the blade. The shield serves to stiffen and protect the blade against bird strikes and hailstones (¶4-¶6) to provide a strong, lightweight fan blade (¶3). The teachings of Gondre are appropriate for a fan with a radius of 80 to 90 inches (¶54), which overlaps with the claimed range of 78 to 84 inches. COMBINATION 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 blades of Kamat to have a metal leading edge protectors on the composite fan blades, with the protector covering 15% to 25% of the pressure and suction sides to provide an APF in the range of 0.2 to 0.3, to obtain the benefit of a lightweight, impact resistant fan blade with sufficient bonding area to adhere the protector to the blade and overall appropriate stiffness and impact resistance . This is a provisional nonstatutory double patenting rejection. 07-30-03-h AIA Claim Interpretation No claim limitations are interpreted under 112(f). According to ¶347, the leading edge length LL can be defined by the greater of the length LL1 and the length LL2. Claim Rejections - 35 USC § 112 07-30-02 AIA 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. 07-34-01 AIA Claim s 1-20 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 pre-AIA the applicant regards as the invention. Claim 1 at the last 3 lines recites the limitation “a ratio of the trailing edge fan radius RFan_LE to the trailing edge hub radius RHub_LE”. These quantities were previously introduced with the subscript “TE” to match the “t” in “trailing.” This raises confusion as to what quantities form the ratio, and whether it pertains to the leading edge or to the trailing edge. Claim 10 recites the limitation “a trailing edge fan radius RFan_TE, and the fan assembly further defines a trailing edge hub radius RHub_TE.” These elements were previously introduced in claim 1, causing confusion. Claim 10 recites an equation with RFan_LE and RHub_LE, but these elements are defined in the claim, rendering the claim indefinite. Claim 12 recites the limitation “a trailing edge fan radius RFan_TE, and the fan assembly further defines a trailing edge hub radius RHub_TE.” These elements were previously introduced in claim 1, causing confusion. Claim 12 recites an equation with RFan_LE and RHub_LE, but these elements are defined in the claim, rendering the claim indefinite. Claim 17 at the last 3 lines recites the limitation “a ratio of the trailing edge fan radius RFan_LE to the trailing edge hub radius RHub_LE”. These quantities were previously introduced with the subscript “TE” to match the “t” in “trailing.” This raises confusion as to what quantities form the ratio, and whether it pertains to the leading edge or to the trailing edge. Claim 19 recites “the ratio of the leading edge fan radius RFan_LE to the leading edge hub radius RHub_LE.” The ratio and each of the two radii lack antecedent basis in the claim. The remaining rejected claims are rejected for their dependence on an indefinite claim. Claim Rejections - 35 USC § 103 07-20-aia AIA 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. 07-21-aia AIA Claim s 1-12, 15, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Kamat (US 12,012,901 published 18 June 2024 which is more than 1 year before the effective filing date of this CIP application, which is 18 July 2025 or 07 July 2025) in view of Gondre (US 2023/0392502) and any one of Gray (NASA CR-174766), Gliebe (NASA CR-2003-212525), or Rauch (NASA CR-120992), as evidenced by Breen (US 2020/0173371) . PNG media_image1.png 196 1395 media_image1.png Greyscale PNG media_image2.png 298 1431 media_image2.png Greyscale Regarding claim 1 , Kamat discloses: A turbomachinery engine comprising: a fan assembly comprising a plurality of fan blades (104, 204, 304, 404 in Figs 1-4), wherein the fan assembly comprises a diameter within a range of 78-84 inches (col 5 lines 1-7, col 15 lines 29-35), wherein the plurality of fan blades comprises a first fan blade being a composite fan blade (col 15 lines 20-28) comprising a composite body extending chordwise from a body leading edge to a body trailing edge (see 104, 204, 304, 404 in Figs 1-4), and … a low-pressure compressor comprising exactly three stages (col 8 lines 26-29, 32-36: “As another example, an engine can comprise a three stage low-pressure compressor, a 10 stage high-pressure compressor, a two stage high-pressure turbine, and a three stage low-pressure turbine…. As another example, an engine can comprise a three stage low-pressure compressor, a 10 stage high-pressure compressor, a two stage high-pressure turbine, and a four stage low-pressure turbine.” col 8 lines 40-42 “an engine can comprise a 1-3 stage low-pressure compressor, an 8-11 stage high-pressure compressor, a 1-2 stage high-pressure turbine, and a 3-5 stage low-pressure turbine”); a high-pressure compressor comprising 8-11 stages (col 8 lines 26-29, 32-36); a combustor (in all of the engines, 232 specifically described in col 7 lines 18-39, 316 in col 12 line 66 – col 13 line 8, 432 in col 14 lines 48-49); a high-pressure turbine comprising exactly two stages (col 8 lines 26-29, 32-36); a low-pressure turbine comprising 3-4 rotating stages (col 8 lines 26-29, 32-36), wherein each rotating stage of the low-pressure turbine comprises an annular exit area defined by a tip radius of a trailing edge of any one blade of the rotating stage and a hub radius of the any one blade of the rotating stage at an axial location aligned with the tip radius, wherein the low-pressure turbine comprises an area ratio equal to the annular exit area of an aft-most rotating stage of the low-pressure turbine divided by the annular exit area of a forward-most rotating stage of the low-pressure turbine, and wherein the area ratio is within a range of 2.0-5.1 (col 16 line 52 – col 17 line 3, see “AREA RATIO” column for Engines 3, 7, and 10-14 in Figs 9 and 12); and a gearbox including an input and an output, wherein the input of the gearbox is coupled to the low-pressure turbine and comprises a first rotational speed, wherein the output of the gearbox is coupled to the fan assembly and has a second rotational speed, and wherein a gear ratio of the first rotational speed to the second rotational speed is within a range of 3.0-3.3 (Engines 3, 7, and 10-14 in Figs 9 and 12),… Kamat does not disclose: a leading edge protector having a protector leading edge different from, and receiving at least a portion of, the body leading edge, wherein a leading length (LL) extends chordwise from the protector leading edge to an end of the leading edge protector, and a chord length (CL) extends chordwise from the protector leading edge to the body trailing edge, wherein the leading length (LL) is related to the chord length (CL) by an airfoil protection factor (APF) equal to (LL)/(CL), APF being greater than or equal to 0.2 and less than or equal to 0.3; wherein the first fan blade defines a trailing edge fan radius RFan_TE, and the fan assembly defines a trailing edge hub radius RHub_TE, the gas turbine engine defining a bypass ratio greater than or equal to 10 and less than or equal to 100 and a ratio of the trailing edge fan radius to the trailing edge hub radius RHub_LE greater than or equal to 2.38:1 and less than or equal to 5.83:1. Kamat discloses “a high-bypass turbofan engine” (col 12 lines 44-47), which would be interpreted by one of ordinary skill to have a bypass ratio between 10 and 100. Gondre teaches: a gas turbine engine fan blade made of a fiber reinforced polymer (¶11) with a titanium alloy metal shield (13, ¶40) on the leading edge. The shield “fins extend over a length greater than or equal to 15% and less than or equal to 25% of a chord length of the airfoil” (¶53). Examiner notes that the claimed APF is defined from the leading edge of the protector (shield), whereas Gondre discloses the % of the composite pressure and suction sidewalls. Nonetheless, the nose portion is generally short in chord length compared to the airfoil and the shield. For example, Fig 1 shows, near the root, that composite blade extends far into the shield. Likewise, Fig 2 shows that the fins 14 are much longer in chord length than the nose 13, as the ends of the fins cannot even be seen at the right side of the drawing. Thus, given that Gondre teaches a range of 15 to 25%, the addition of the chord length of the nose portion would not push all embodiments of Gondre over an APF of 30%. It is both self-evident and known in the art that the surface area of the connection (i.e., the portion of the pressure and suction sides covered) affects the amount of area available for attachment, such as by an adhesive. Likewise, the overall amount of metal affects the stiffness and impact resistance of the blade. The shield serves to stiffen and protect the blade against bird strikes and hailstones (¶4-¶6) to provide a strong, lightweight fan blade (¶3). The teachings of Gondre are appropriate for a fan with a radius of 80 to 90 inches (¶54), which overlaps with the claimed range of 78 to 84 inches. COMBINATION 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 blades of Kamat to have a metal leading edge protectors on the composite fan blades, with the protector covering 15% to 25% of the pressure and suction sides to provide an APF in the range of 0.2 to 0.3, to obtain the benefit of a lightweight, impact resistant fan blade with sufficient bonding area to adhere the protector to the blade and overall appropriate stiffness and impact resistance. Kamat discloses low pressure turbines that are usable with a variety of engine configurations shown in Figs 1-4 (col 18 lines 14-17, col 20 lines 7-11, col 21 lines 29-34), including a high-bypass turbofan as shown in Fig 3. Kamat is silent on the specific geometry of the fan and hub for the turbofan. However, given the substantial versatility of Kamat, it is reasonable to expect that Engines 3, 7, and 10-14 of Kamat, when embodied as a turbofan an shown in Fig 3, would work with various fans. Below are presented three references with high-bypass turbofans, and sufficient detail of the fan section to determine the fan blade and hub radius at the leading and trailing edge. Gray Candidate 1 discloses a 2-spool high bypass turbofan with a bypass ratio of 12.8 (p.45) and a gear ratio of 3.12 (p.50). Gray discloses blades made of hollow titanium alloy (p.27). Another reference, Rauch, also discloses titanium blades. It is not clear what material is used for the blades of Gliebe, which has two engines of interest: Gliebe Engine 3/S45 at the top of Fig 4 and Engine 4/S30 at the bottom of Fig 4 (p.7 ¶4). Each of these references is decades old, and advancements in composite blade manufacturing have increased the feasibility of composite blades. As evidenced by Breen, one would have a reasonable expectation of success in making the composite fan blades of Kamat/Gondre in the form/proportions of Gray Candidate 1, Gliebe S45, Gliebe S30, and Rauch, despite these references having blades that may be made of a different material. Specifically, Breen teaches that a composite fan blade with a metal leading edge (¶32) can be used to make a fan having a hub to tip ratio between 0.2 and 0.4 (¶41) for a fan diameter of about 86 to 157 inches (¶24) with 14-26 fan blades (¶35). As a high-bypass (¶27) geared (¶16) turbofan (¶53), the engine shown in Breen Figs 1-2 generally has a similar configuration to Gray, Gliebe, and Rauch. The table below shows that Gray, Gliebe, and Rauch have a hub to tip ratio (at the leading edge, as is standard) in the range of 0.2 to 0.4. Gray Candidate 1, Gliebe S30, and Rauch Fig 10 were measured in the pdf files using the Adobe Acrobat measuring tool. The measurements are in the original pdf files, which are annotated and attached to this office action. The inches shown on the screenshots below will not match the measurement in this Microsoft Word document. Since the claims deal with ratios, the measurements are left in their original form as inches on the scale drawing, and not scaled up to full size. Gliebe S45 was considered worthwhile, even though the bypass ratio is slightly outside the claimed range because the bypass ratio depends on the relative dimensions of the core and the fan, not simply the geometry of the fan and fan hub. TE hub radius TE tip radius Hub to Tip Ratio (trailing) LE hub radius LE tip radius Hub to Tip Ratio (leading) Actual fan diameter (in), blade count Bypass ratio Gray Cand 1, p.31 0.85 2.03 0.42 0.53 2.07 0.26 106.8, 24 (p.34) 12.8 (p.29) Gliebe Fig 4 (top)/Engine 3 S45 0.62 1.63 0.38 0.50 1.64 0.30 106, 22 (p.29) 9.81 Gliebe Fig 4 (bottom)/Engine 4 S30 0.66 1.96 0.34 0.59 1.96 0.30 130, 22 (p.29) 15.75 Rauch Fig 10 1.25 3.02 0.42 1.18 3.02 0.39 48, 32 (p.42) 12.5 Gray, Candidate 1: PNG media_image3.png 783 1430 media_image3.png Greyscale R-fan-TE : R-hub-TE = PNG media_image4.png 53 333 media_image4.png Greyscale FLTCF = PNG media_image5.png 72 187 media_image5.png Greyscale = PNG media_image6.png 55 328 media_image6.png Greyscale FLTOR = PNG media_image7.png 72 190 media_image7.png Greyscale = PNG media_image8.png 56 338 media_image8.png Greyscale Gliebe, S45 (top in Fig 4): PNG media_image9.png 1361 1775 media_image9.png Greyscale R-fan-TE : R-hub-TE = PNG media_image10.png 54 321 media_image10.png Greyscale FLTCF = PNG media_image5.png 72 187 media_image5.png Greyscale = PNG media_image11.png 57 323 media_image11.png Greyscale FLTOR = PNG media_image7.png 72 190 media_image7.png Greyscale = PNG media_image12.png 54 306 media_image12.png Greyscale Gliebe S30 (bottom in Fig 4): R-fan-TE : R-hub-TE = PNG media_image13.png 54 350 media_image13.png Greyscale FLTCF = PNG media_image5.png 72 187 media_image5.png Greyscale = PNG media_image14.png 56 320 media_image14.png Greyscale FLTOR = PNG media_image7.png 72 190 media_image7.png Greyscale = PNG media_image15.png 56 324 media_image15.png Greyscale Rauch discloses a geared turbofan having a fan diameter of 48 inches and a bypass ratio of 12.5. The fan blades are made of titanium (p.96). Rauch Fig 10: PNG media_image16.png 695 1428 media_image16.png Greyscale R-fan-TE : R-hub-TE = PNG media_image17.png 56 396 media_image17.png Greyscale FLTCF = PNG media_image5.png 72 187 media_image5.png Greyscale = PNG media_image18.png 55 324 media_image18.png Greyscale FLTOR = PNG media_image7.png 72 190 media_image7.png Greyscale = PNG media_image19.png 54 321 media_image19.png Greyscale The claimed range for the ratio of the trailing edge fan radius to the trailing edge hub radius is 2.38 to 5.83. The Examiner has access to very few references with sufficient detail to determine the claimed ratio, yet each of these three references teaches a high bypass turbofan with a fan having the claimed ratio. Rauch is notably smaller than the claimed range of 78-84 inches, at 48 inches fan diameter, while the other three are larger at 106 – 130 inches. This, together with Breen, suggests a large fan diameter is not required, and that the geometry of these references is applicable to a fan in the claimed range of 78-84 inches. Claim Gray Cand 1 Gliebe S45 Gliebe S30 Rauch 2.38 – 5.83 2.39 2.63 2.97 2.42 COMBINATION 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 engine of Kamat as modified by the leading edge protector of Gondre to have the fan geometry of either Gray Candidate 1, or Gliebe S45, or Gliebe S30, or Rauch Fig 10. Kamat engines 3, 7, and 10-14 are disclosed as usable with a diverse array of engines, including a high-bypass geared turbofan. Thus, it would be obvious to incorporate any one of these prior art fans from the high-bypass turbofans of Gray, Gliebe, or Rauch. Notably, any one of Gray, Gliebe S45, Gliebe S30, and Rauch taken individually teaches the claim limitations concerning the radius ratio, FLTCF, and FLTOR. This is not a 6-reference 103, but rather 4 parallel 3-reference 103s. Yet they are presented together because each additional reference that discloses the claimed parameters strengthens the case for obviousness. Regarding claim 2 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of S30 teaches: the ratio of the trailing edge fan radius RFanTE to the trailing edge hub radius RHub_TE is greater than or equal to 2.72:1 and less than or equal to 4.46:1 (see Gliebe-4-bottom calculations above). Regarding claim 3 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, S45, S30, or Rauch, teaches: the ratio of the trailing edge fan radius RFanTE to the trailing edge hub radius RHub_TE is less than or equal to 3.08:1 (all references, see summary table above). Regarding claim 4 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of S30 teaches: the bypass ratio is greater than or equal to 13 and less than or equal 25 (see Gliebe Fig 4(bottom), bypass ratio is listed on the figure). Regarding claim 5 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of S30 teaches: the turbomachine defines a working gas flowpath and an inlet to the working gas flowpath, wherein the bypass ratio is 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 (This is the standard definition of bypass ratio, see Kamat fig 3 and Gliebe S30). Regarding claim 6 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of Gliebe S30 teaches: the bypass ratio is greater than or equal to 15 and less than or equal 25 (see Gliebe Fig 4(bottom), bypass ratio is listed on the figure). 4.46:1 (see Gliebe-4-bottom calculations above). Regarding claim 7 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch, teaches: the fan blade is formed of a composite material (Kamat col 15 lines 20-28, Gondre ¶11). Regarding claim 8 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch, teaches: the composite body is formed of a different material (Gondre ¶11: fiber reinforced polymer) than the leading edge protector (Gondre ¶40: titanium alloy metal shield). Regarding claim 9 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch, teaches: the leading edge protector is formed of a metallic material (Gondre ¶40: titanium alloy metal shield). Regarding claim 10 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch, teaches: the first fan blade further defines a trailing edge fan radius RFan_TE, and the fan assembly further defines a trailing edge hub radius and 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_image5.png 72 187 media_image5.png Greyscale The following table is a summary of the calculations for FLCTF above. Claim FLTCF Gray Cand 1 Gliebe S45 Gliebe S30 Rauch 1.05-1.8 1.64 1.25 1.11 1.06 Regarding claim 11 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, or Gliebe S30, teaches: the FLTCF is greater than or equal to 1.07 and less than or equal to 1.65 (see table for claim 10, excluding Rauch). Regarding claim 12 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch teaches: the first fan blade further defines a trailing edge fan radius RFan_TE, and the fan further defines a trailing edge hub radius 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_image7.png 72 190 media_image7.png Greyscale Claim FLTOR Gray Cand 1 Gliebe S45 Gliebe S30 Rauch 1.03-1.5 1.31 1.14 1.05 1.04 Regarding claim 15 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch teaches: the high-pressure compressor comprises exactly nine stages (Kamat: col 8 lines 40-42 “an engine can comprise a 1-3 stage low-pressure compressor, an 8-11 stage high-pressure compressor, a 1-2 stage high-pressure turbine, and a 3-5 stage low-pressure turbine”). Regarding claim 16 , the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch teaches: the low-pressure turbine comprises exactly four rotating stages (Kamat engines 10-14) . 07-21-aia AIA Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Kamat (US 12,012,901 published 18 June 2024 which is more than 1 year before the effective filing date of this CIP application, which is 18 July 2025) in view of Gondre (US 2023/0392502) and Gliebe (NASA CR-2003-212525), as evidenced by Breen (US 2020/0173371), as applied to claim 1, and further in view of Decker (US 2006/0228206) . Regarding claim 14 , the combination does not disclose: the fan assembly comprises exactly 20 fan blades. Gliebe S45 and S30 each teach 22 fan blades (p.29). Decker teaches: “The reduction in fan blade number while maintaining substantially constant the chord to diameter C/D ratio at the airfoil tips has significant advantages in the new turbofan including an increase in efficiency while maintaining adequate stability and stall margin, as well as reducing noise, as well as reducing weight and cost due to the fewer fan blades” (¶53). COMBINATION It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have further modified the engine of Kamat as modified by Gondre and Gliebe by reducing the fan blade count to 20 to increase efficiency and reduce weight and cost . Allowable Subject Matter Claims 17-20 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA), 2nd paragraph, set forth in this Office action, and if the Double Patenting rejection is overcome. 07-43-02 Claims 13 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim, and if the Double Patenting rejection is overcome. 13-03-01 AIA The following is a statement of reasons for the indication of allowable subject matter: For claims 17-20, the nearest prior art is the engine of Kamat as modified by the leading edge protector of Gondre and the fan of one of either Gray, Gliebe S45, Gliebe S30, or Rauch. Regarding claim 17, Kamat does not teach: the area ratio is within a range of 2.55-2.65 in conjunction with a low-pressure turbine comprising exactly four rotating stages… a gear ratio of the first rotational speed to the second rotational speed is within a range of 3.0-3.3 as well as the other limitations. Specifically, the engines with 4 stage low pressure turbines that have the claimed gear ratio are engines 10-14, and these engines each have an area ratio in a range from 3.14 to 4.53 (see table of Kamat Fig 12). Claim 13 recites an area-EGT ratio within a range of 1.2-1.3. However, the engines in Kamat that meet the other claim limitations, engines 3, 7, and 10-14, each have an area-EGT ratio in a range from 1.38-1.58. Examiner’s Note The independent claims recite the ratio of trailing edge tip radius to trailing edge hub radius, which is not a typical parameter disclosed in the prior art. However, it is closely related to the hub to tip ratio, which is commonly disclosed in the prior art. The claimed parameter is not simply the inverse of the hub to tip ratio because the hub to tip ratio is characteristically measured at the leading edge of the blade. Thus, the hade angle of the hub (which describes the inclination due to the cone shape), and any angle at the blade tip will also affect the recited ratio. Nonetheless, the claimed ratio, when the inverse is taken, corresponds to a hub to tip ratio, measured at the trailing edge, of 0.17 to 0.42. Due to hubs often having a conical shape, one would expect the hub to tip ratio at the trailing edge to be somewhat higher than at the leading edge. However, when leading edge hub to tip ratios of 0.2 to 0.4 are known, as from Breen (US 2020/0173371) ¶23 working with the same materials (¶32) and the same fan diameter (¶24), a trailing edge hub to tip ratio in a range from 0.17 to 0.42 is not likely to be patentable. Likewise, there is a broad desire in the art to reduce the hub to tip ratio. Among others, Lamboy (US 2014/0219805) teaches that, for a turbofan, “It is desirable for the fan to have the smallest possible radius ratio, i.e., the radius of the hub to the radius of the blade tips, because minimizing radius ratio maximizes fan inlet area and allows the greatest possible thrust for a given fan diameter” (¶4). “The radius ratio may be lowered by reducing the hub diameter” (¶5). Notwithstanding the technical difficulties that may arise from reducing the hub radius, the instant application does not disclose any advancements in blade or hub manufacturing or materials that would enable a further reduction in hub radius as compared to the prior art. The Examiner is wary of allowing a patent for a structure similar to other structures in the art, but not identifiable as such because it is claimed in a non-standard way. Pertinent Prior Art 07-96 AIA The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Analysis of Gray Candidate 5 was suspended because the TE ratio, at 2.36, is just outside the claimed range . Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to TOPAZ L ELLIOTT whose telephone number is (571)270-5851. The examiner can normally be reached Monday-Friday 7 a.m. - 4 p.m. EST. 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, Courtney Heinle can be reached on (571) 270-3508. 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. /TOPAZ L. ELLIOTT/Primary Examiner, Art Unit 3745 Application/Control Number: 19/274,172 Page 2 Art Unit: 3745 Application/Control Number: 19/274,172 Page 3 Art Unit: 3745 Application/Control Number: 19/274,172 Page 4 Art Unit: 3745 Application/Control Number: 19/274,172 Page 5 Art Unit: 3745 Application/Control Number: 19/274,172 Page 6 Art Unit: 3745 Application/Control Number: 19/274,172 Page 7 Art Unit: 3745 Application/Control Number: 19/274,172 Page 8 Art Unit: 3745 Application/Control Number: 19/274,172 Page 9 Art Unit: 3745 Application/Control Number: 19/274,172 Page 10 Art Unit: 3745 Application/Control Number: 19/274,172 Page 11 Art Unit: 3745 Application/Control Number: 19/274,172 Page 12 Art Unit: 3745 Application/Control Number: 19/274,172 Page 13 Art Unit: 3745 Application/Control Number: 19/274,172 Page 14 Art Unit: 3745 Application/Control Number: 19/274,172 Page 15 Art Unit: 3745 Application/Control Number: 19/274,172 Page 16 Art Unit: 3745 Application/Control Number: 19/274,172 Page 17 Art Unit: 3745 Application/Control Number: 19/274,172 Page 18 Art Unit: 3745 Application/Control Number: 19/274,172 Page 19 Art Unit: 3745 Application/Control Number: 19/274,172 Page 20 Art Unit: 3745 Application/Control Number: 19/274,172 Page 21 Art Unit: 3745 Application/Control Number: 19/274,172 Page 22 Art Unit: 3745 Application/Control Number: 19/274,172 Page 23 Art Unit: 3745
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