DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 3 March 2026 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-6 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the arrangement of a ridge structure on a surface. The orientation of the ridge structure is provided by a ridgeline angle, θR, which is claimed between the boundary layer edge velocity angle, θe, and the cross-flow instability angle, θcf. The angles θe and θcf are properties of the flow over the surface, not of the surface itself. The ridgeline angle, θR, is thus defined by external properties of the system.
Further, the angles θe and θcf are properties of the boundary layer and the wavefront of cross-flow instability, respectively. These flows are dependent upon velocity of the surface through the flow or flow over the surface, temperature/density of the fluid, and angle of the surface relative to the flow. Each of these are variable during use of the surface (different altitudes, speeds, etc.). As these angles change as the variables change, the ridgeline angle, θR, would necessarily change accordingly to maintain the claimed relationship.
The disclosure requires that certain values are “assumed” in order to provide bases for the design (see e.g. [0028], “when it is assumed that a transition occurs at….”, and [0030], “the wavenumber in the span direction of the wave-shaped ridge structure is assumed to be a wavenumber…” [emphasis added]). In other words, external flow properties must be decided before the design may be rendered. Further, the prior remarks note that the examples are “non-limiting” (6 March 2025, page 6).
The limitation “in an assumed cruise condition” may provide for some variables (e.g. expected speed), however only as estimations. However, even these estimated variables, and the actual experienced conditions, are not provided. Cruise conditions at 20,000 feet are different than those at 38,000 feet (e.g. temperature and density variations). [0027] indicates that in a cruising state the boundary layer transition occurs at N based on a linear stability analysis. This N value is also indicated via Fig 4, which requires the standing wave periodical wavenumber (β), also a result of flow conditions([0026]). [0027] also further states that the larger the turbulence (a factor of flow parameters and angle of attack, i.e. the angle of the wing relative to the airflow), the lower the threshold tends to be. Accordingly, these numbers have to be “assumed” prior to design, as evidenced by [0027], which for the purpose of example, assumes an N value.
The arrangement is thus unclear, as a static physical arrangement is dependent upon unknown, variable, and adjustable external factors of use.
Similarly for claims 2-5, which recite/incorporate similar language to claim 1 and/or recite further variable external parameters (e.g. boundary layer thickness).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1-6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Farouz-Fouquet (US 2019/0210714).
Regarding independent claims 1, 7, and 8:
As best understood, Farouz-Fouquet discloses a ridge structure comprising a plurality of ridge elements (12) at an angle (as seen in Fig 3) on a leading edge surface of a wing in cruise condition ([0069]) having a swept-back angle (angle φ), and the ridge elements having vertices at a constant interval spanwise (as seen in Figs 3 and 8).
Farouz-Fouquet notes the desire to decrease cross-flow instability along the wing ([0004]-[0005]), but does not disclose a ridgeline angle between an angle of a boundary layer external edge flow line, θe, and a cross-flow instability flow line, θcf.
The ridgeline angle is a result effective variable. The purpose of the angle is to decrease the crossflow instability, based on the flow encountered during flight. Based on various design parameters, such as differing wing sweep, angle of incidence, dihedral/anhedral, flight speeds, etc., the flow over the wing would be altered in direction, size, etc., and one of ordinary skill could readily adjust (during design) the ridgeline angle based on the flow over the surface to accommodate these differences using routine experimentation.
Accordingly, it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have modified Farouz-Fouquet to provide the ridgeline angle between the angles θe and θcf as this would provide the desired crossflow characteristics for reducing crossflow instability during the expected flight performance, and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. See MPEP 2144.05 II.
The resultant structure would be “configured to” stationarily maintain a vortex row along the ridgeline angle ([0061]).
Regarding claims 2-6:
The discussion above regarding claim 1 is relied upon.
The claims further define the ridge elements based on the flow. This would be mere optimization of the components to reduce the crossflow instability, and would accordingly be modified in the like manner to that described above.
Response to Arguments
Applicant's arguments filed 3 March 2026 have been fully considered but they are not persuasive.
In response to applicant’s argument that the claims are definite, the arguments further suggest that external properties are required in order to determine the shape of the riblets. The remarks state that the application is characterized by “setting parameters and providing a ridge structure based on mainstream flow.” The disclosure requires that certain values are “assumed” in order to provide bases for the design (see e.g. [0028], “when it is assumed that a transition occurs at….”, and [0030], “the wavenumber in the span direction of the wave-shaped ridge structure is assumed to be a wavenumber…” [emphasis added]). In other words, external flow properties must be decided before the design may be rendered. Further, the remarks note that the examples are “non-limiting” (page 6). The disclosure is further silent to the parameters of cruise flight, e.g. altitude to aid one of ordinary skill determine the flow characeristics encountered. The design, as disclosed, is not provided for a set assumed condition of flight, but for any flight conditions which may be encountered.
The claim recites “in an assumed cruise condition”, however still lacks various parameters required to determine a fixed riblet design, such as the altitude (which affects temperature and density of the air, speed of sound, etc.). The “flow field” is not defined by the design stage, but rather estimated, and the claims require the design to be in accordance with the actual encountered flow, not the predicted flow estimated during design.
Further still, the claim encompasses a general “cruise condition.” The claim must then account for various cruise conditions to be chosen. However, using the same design process, different initial values would lead to arrangements of the claimed structure. These initial values are based on the above-noted external factors, such as cruise altitude and speed. Since the structure changes based on the intended environment of use, it would become unclear when the prior art would infringe on the claimed invention, as the structure is variable dependent upon the intended operation Accordingly, the scope of the claim is unclear, as unknown external parameters are required to design and provide the structure claimed.
In response to applicant's argument that Farouz-Fouquet does not maintain a vortex row formed by the ridge structure along the ridgeline angle, but rather cancels the vortex, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Farouz-Fouquet discloses in [0061]-[0062] that a single vortex is created. Further, any cancellation occurs “locally, downstream”, which, as seen in Fig 8, occurs downstream enough to permit the vortex to flow unimpeded for a time. Further, the vortex may not necessarily be cancelled, but rather “reduced”, which indicates the vortex remains. Further still, the claims do not indicate or require any length of flow to be maintained.
In response to applicant’s argument that Farouz-Fouquet would not operate as claimed, the operation would depend on external factors, and thus the system would be “configured to” maintain the flow along the angle depending upon the chosen flight operation (e.g. altitude, speed, etc.). Further, the applicant has not submitted any evidence of unpredictable or unexpected results to indicate the arrangement is anything more than an optimization of form.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). 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 Joseph W Sanderson whose telephone number is (571)272-6337. The examiner can normally be reached Mon-Thu 6-3 ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Anna Momper can be reached on 571-270-5788. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JOSEPH W SANDERSON/ Primary Examiner, Art Unit 3619
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