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 .
This is in response to the correspondence filed on 1/7/2026.
Applicant elected without traverse
Group I: Species III, Fig. 1D;
Group II: Species 11, Fig. 5J;
Group III: Species B, Fig. 7
in the reply filed on 2/7/2025.
Therefore Figures 1B-1C are non-elected species; Figs. 3B, 5A-5I, 5N-5R, 13A-13B are non-elected species; Fig. 6 is non-elected species.
In the reply filed on 2/7/2025 Applicant states Claims 1-4, 10-11, 15-17, and 20 encompass the elected species.
During a telephone conversation with Tim Baumann on 7 May 2025 an election was made to consider Figure 13F as non-elected species, an additional step to the election to prosecute the invention as discussed above and on the correspondence filed 2/7/2025.
Claims 5-9, 12-14, 18-19, and 25 are cancelled.
Drawings
The drawings are objected to under 37 CFR 1.83(a) because they fail to show “a first surface of the flow conditioning structure” and “a second surface of the flow conditioning structure” as described in the specification. Any structural detail that is essential for a proper understanding of the disclosed invention should be shown in the drawing. MPEP § 608.02(d). 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.
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 2, 21, and their dependent claims, 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.
Claims 2 and 21 recite the limitation “a second surface of the unducted thrust producing apparatus.” Because the limitation is for “a second surface of the unducted thrust producing apparatus”, it is unclear if the invention also includes “a first surface of the unducted thrust producing apparatus” and where each surface is located.
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.
Claim(s) 1-3, 10, 20-22, 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Long 20150134270 in view of Long 20150134270 as evidenced by Geyer “design and Construction of a test Stand for Noise Measurements of Model Propellers” of January 2013 (NPL provided by applicant, filed 2/20/2026) and Barnett 5713212.
Regarding claim 1, Long teaches:
A system for static testing (Figs 1-3), the system comprising:
a single flow conditioning structure (inter alia, 16) aligned and disposed about a single central axis (through the center of Fig. 2, coinciding with the axis of the engine’s shafts) of thrust producing apparatus (inter alia, engine 12, fan 30, Fig. 2),
wherein the thrust producing apparatus has a propeller (fan 30 in Fig.2) that generates thrust in a working fluid (working fluid illustrated by light color arrows entering and exiting the apparatus, from left to right in Fig. 2) by rotating about the central axis (same axis as discussed above, Figs. 2).
the propeller being comprised of blades each with a free end (Image below) remote from the central axis (axis as discussed, and through the center of 12),
each blade also having a leading edge (forward portion of each blade, image below) where the working fluid enters (light shade arrow on the left side of Fig. 2) during forward thrust operation (thrust in direction opposite of the flow indicated by the light shade arrows, Fig. 2); and
wherein the single flow conditioning structure (16) comprises a structure forming a passage (passage from left to right, flowing between 16) and the structure forming the passage changes a speed (the surfaces 16 will affect pressure, drag, boundary layer, influencing the speed) and a direction (16 forces the flow to be directed horizontally, from left to right, Fig. 2) of the working fluid drawn into the thrust producing apparatus (flow indicated by light shade arrows, Fig. 2) so as to approximate operational flight speeds and operational flight directions of the working fluid entering the unducted thrust producing apparatus during operations of a vehicle (“Inlet bell mouth 16 guides airflow into turbine engine system 12, for example using a bell mouth or similar configuration to measure airflow and reduce losses in the absence of ram air pressure present during flight operations.“ [0021]) the working fluid being directed across an entire span of the blade (16 directs flow over the entire span of 30). With regard to the recitation of the unducted thrust producing apparatus, Long discloses a structure that is capable of use with an unducted and a ducted turbofan. See para. [0022]. Thus, the structure of the single passive flow conditioning device as claimed is anticipated by the structure of Long. However, if at a later time, it is determined that the unducted thrust producing apparatus is a positively recited limitation in the claim, Long teaches alternate embodiments rendering obvious the unducted thrust producing apparatus.
Long’s Figs.1-3 show a turbofan and not an unducted thrust producing apparatus as claimed, but Long teaches “Alternatively, turbine engine system 12 may be configured as a turbojet, turboshaft or turboprop engine” [0022], and “The present disclosure relates generally to performance evaluation, including the evaluation of turbine engine performance. More particularly, the disclosure relates to systems and methods for evaluating the performance of turbine engine systems and subsystems, including, but not limited to, turbofan, turboshaft, and turboprop engines, and industrial gas turbine engines” [0002], and a turboprop engine is an unducted thrust producing apparatus.
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to use Long’s invention with a turboprop engine, as taught by Long (in this case, one of ordinary skill in the art would interpret the modification to comprise, inter alia, eliminating the duct of Long’s engine system 12 seen in Fig. 2, and placing the turboprop propeller at an analogous location as the fan of the engine seen in Fig. 2), in order to test a engine and “to determining turbine system stability utilizing a computer system or stability processor” Long [0005]. Furthermore, a system for testing an unducted propeller, using a single passive flow conditioning structure aligned and disposed about a single central axis, the propeller being comprised of blades each with a free end remote from the central axis, each blade also having a leading edge where the working fluid enters, wherein the single flow conditioning structure comprises a structure forming a passage and the structure forming the passage is configured to be effective to control changes a speed and a direction of the working fluid to approximate operational flight speeds and operational flight directions of the working fluid entering the unducted propeller during operations of a vehicle, the working fluid being directed across an entire span of the blade was known at the time of the invention as is evidenced by Geyer “design and Construction of a test Stand for Noise Measurements of Model Propellers” of January 2013 (NPL provided by applicant, filed 2/20/2026) Fig. 5, and also evidenced by Barnett 5713212, see Fig. 1 and “The air-driven generator 12 may be seen in FIG. 1 to include a housing 16 which supports a variable-pitch propeller 18” Col 4 ll. 24-30. It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to use Long's testing structure to test unducted thrust producing apparatus (turboprop, as discussed above) in order to provide “an apparatus may be provided for ground-testing […] propeller” as taught by Barnett, In Col 3 ll. 1-3.
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Regarding claim 2, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 1.
Long further teaches:
wherein a propeller tip (Image below, Fig. 2) is located at an intersection of the free end and the leading edge of the blades (image below);
wherein a first surface of the single flow conditioning structure (a first surface of 16) includes a point that is nearest to the propeller tip (right end portion of 16 is closest to the propeller tip), and a second surface of the unducted thrust producing apparatus (surface of the nose cone of the engine, seeing on the left side of Fig. 2) form the passage (passage between the surface of 16 and the nose cone on the left side of Fig. 2);
wherein the first surface guides the working fluid that is between the first surface and the central axis (Image below, Fig.2 has a central axis through the center of 12) and
the second surface guides the working fluid that is between the second surface and the first surface (flow through the inner portion of 16, Image below);
wherein a passage length (L in Image below) is defined as a straight-line distance from a forward-most point of the first surface and the point on the first surface nearest to the propeller tip (right portion of 16, indicated by the second arrow in the Image below, the two points defining L are indicated by the arrows);
wherein passage height (H indicated in the image below) is defined as a distance between the first surface and the second surface (Image below, the two points defining H are indicated by the arrows); and
wherein L/H > 1.0 (as seen in the image below, L is significantly larger than H). Furthermore, a greater than 1 ratio between a passage length and a height ,measured between the inner surface of the flow conditioning structure and a central axis, is further evidenced be Barnett Fig 1, Image below.
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Regarding claim 3, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim invention as discussed for claim 2.
Long further teaches:
wherein a propeller tip radius (R) is a distance of the propeller tip from the central axis (from the central axis to the propeller tip indicated in the image below);
wherein, for a surface of the flow conditioning structure that is nearest to the propeller tip (right side of 16), the point on the surface that is nearest to the propeller tip has a distance (S) from the central axis (in the image below S is from the right most point of 16 to the central axis); and
wherein S/R < 1.2 (as seen in the image below, the difference between S and R is less than 1.2). Furthermore, a S/R <1.2 ratio is further evidenced be Barnett Fig 1, Image below shows S and R to the right of the image.
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Regarding claim 10, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 1. Long further teaches:
wherein the single flow conditioning structure comprises a rounded inlet (Long Fig. 1, reproduced below, shows the inlet to the right of the image and it is rounded).
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Regarding claim 17, Long in view of Long, as evidenced by Geyer and Barnett, teaches the invention as discussed for claim 1.
Long in view of Long as evidenced by Geyer and Barnett does not explicitly teach the propeller absorbs power for a non-dimensional power coefficient >1 as claimed.
However, Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis.
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Long in view of Long, as evidenced by Geyer and Barnett with Otake's structure discussed above in order to achieve “An optimal-efficiency condition of a propeller in a full-power mode has been confirmed in the relationship between the power coefficient Cp and the advance ratio J shown in the graph” Col 4 ll. 45-50
Long in view of Long, as evidenced by Geyer and Barnett and further in view of Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis. While the specific values of Cp >1 is not explicitly indicated, the relationship between Cp and the values seen in Fig. 1 was recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case the Cp of the propeller depending on inter alia, N, as seen on the graph, a variable on the X axis as well, such that the determination of the optimum or workable ranges of said variable, in this case the aircraft travels at a power coefficient > 1, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Cp and its relationship with airplane speed, it has been held that the discovery of optimum or workable ranges, in this case finding “An optimal-efficiency condition of a propeller” (Col 4 ll. 45-50), by experimentation requiring only routine skill in the art, in this case the ability to search for “An optimal-efficiency condition of a propeller”, would have been an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A).
Regarding claim 20, Long teaches:
A method of on-ground testing (aerodynamic testing facility [0010], Fig. 3) of an unducted aircraft engine (turboprop engine [0022]), the method comprising:
providing a thrust producing apparatus having a propeller (30) that generates thrust in a working fluid by rotating about a single central axis (turboprop engine [0022], turboprop engines are known to produce thrust by ),
the propeller being comprised of blades (see 30 has blades in Fig. 2), each with a free end and a leading edge (Image below) where the working fluid enters during a forward thrust operation (light shade arrow on the left side of Fig. 2),
wherein a propeller tip (image below) corresponds to an axial and radial location of an intersection of the free end and the leading edge (image below);
disposing and aligning a single flow conditioning structure (16) about the single central axis (axis from left to right, through 12 and through 16) in proximity to the thrust producing apparatus (16 is in proximity to 12); and
changing a speed (the surfaces 16 will affect pressure, drag, boundary layer, influencing the speed) and a direction (16 forces the flow to be directed horizontally, from left to right, Fig. 2) of the working fluid drawn into the thrust producing apparatus (flow indicated by light shade arrows, Fig. 2) by the single flow conditioning structure so as to approximate operational flight speeds and operational flight directions of the working fluid entering the unducted thrust producing apparatus during operations of a vehicle (“Inlet bell mouth 16 guides airflow into turbine engine system 12, for example using a bell mouth or similar configuration to measure airflow and reduce losses in the absence of ram air pressure present during flight operations“ [0021]), the working fluid being directed across an entire span of the blade (16 directs flow over the entire span of 30).
Long’s Figs.1-3 show a turbofan and not an unducted thrust producing apparatus as claimed, but Long teaches “Alternatively, turbine engine system 12 may be configured as a turbojet, turboshaft or turboprop engine” [0022], and “The present disclosure relates generally to performance evaluation, including the evaluation of turbine engine performance. More particularly, the disclosure relates to systems and methods for evaluating the performance of turbine engine systems and subsystems, including, but not limited to, turbofan, turboshaft, and turboprop engines, and industrial gas turbine engines” [0002], and a turboprop engine is an unducted thrust producing apparatus.
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to use Long’s invention with a turboprop engine, as taught by Long (in this case, one of ordinary skill in the art would interpret the modification to comprise, inter alia, eliminating the duct of Long’s engine system 12 seen in Fig. 2, and placing the turboprop propeller at an analogous location as the fan of the engine seen in Fig. 2), in order to test a engine and “to determining turbine system stability utilizing a computer system or stability processor” Long [0005]. Furthermore, a system for testing an unducted propeller, using a single passive flow conditioning structure aligned and disposed about a single central axis, the propeller being comprised of blades each with a free end remote from the central axis, each blade also having a leading edge where the working fluid enters, wherein the single flow conditioning structure comprises a structure forming a passage and the structure forming the passage is configured to be effective to control changes a speed and a direction of the working fluid to approximate operational flight speeds and operational flight directions of the working fluid entering the unducted propeller during operations of a vehicle, the working fluid being directed across an entire span of the blade was known at the time of the invention as is evidenced by Geyer “design and Construction of a test Stand for Noise Measurements of Model Propellers” of January 2013 (NPL provided by applicant, filed 2/20/2026) Fig. 5, and also evidenced by Barnett 5713212, see Fig. 1 and “The air-driven generator 12 may be seen in FIG. 1 to include a housing 16 which supports a variable-pitch propeller 18” Col 4 ll. 24-30. It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to use Long's testing structure to test unducted thrust producing apparatus (turboprop, as discussed above) in order to provide “an apparatus may be provided for ground-testing […] propeller” as taught by Barnett, In Col 3 ll. 1-3.
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Regarding claim 21, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 20. Long further teaches:
The method of wherein the single flow conditioning structure comprises a structure forming a passage (16 forms a passage within its boundaries);
wherein a first surface of the single flow conditioning structure (a first surface of 16), and
a second surface of the unducted thrust producing apparatus (surface of the nose cone of the engine, seeing on the left side of Fig. 2) form the passage;
wherein the first surface guides the working fluid that is between the first surface and the central axis (Fig. 2) and
the second surface guides the working fluid that is between the second surface and the first surface (Fig 1, image below);
wherein a passage length (L) is defined as a straight-line distance from a forward-most point of the first surface and a point on the first surface nearest to the propeller tip (Image below, the two points defining L are indicated by the arrows);
wherein passage height (H) is defined as a distance between the first surface and the second surface (Image below, the two points defining H are indicated by the arrows); and
wherein L/H > 1.0 (as seen in the image below, L is significantly larger than H). Furthermore, a greater than 1 ratio between a passage length and a height, measured between the inner surface of the flow conditioning structure and a central axis, is further evidenced be Barnett Fig 1, Image below.
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Regarding claim 22, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 21. Long further teaches:
wherein a propeller tip radius (R) is a distance of the propeller tip from the central axis (from the central axis to the propeller tip indicated in the image below);
wherein, the point on the first surface nearest to the propeller tip has a distance (S) from the central axis (in the image below S is from the right most point of 16 to the central axis); and
wherein S/R < 1.2 (as seen in the image below, the difference between S and R is less than 1.2). Furthermore, a S/R <1.2 ratio is further evidenced be Barnett Fig 1, Image below shows S and R to the right of the image.
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Regarding claim 24, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 20. Long further teaches:
wherein the single flow conditioning structure comprises a rounded inlet (Long Fig. 1, reproduced below, shows the inlet to the right of the image and it is rounded).
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Claim(s) 15-17, 26-28 /are rejected under 35 U.S.C. 103 as being unpatentable over Long 20150134270 in view of Long as evidenced by Geyer “design and Construction of a test Stand for Noise Measurements of Model Propellers” of January 2013 (NPL provided by applicant, filed 2/20/2026) and Barnett 5713212 and further in view of Otake 6468035.
Regarding claim 15, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 1. Long further teaches:
wherein the unducted thrust producing apparatus is an aircraft engine used by an aircraft (“turbofan, turboshaft, and turboprop engines” [0002]);
Long is silent about the propeller absorbing the power as claimed.
However, Otake teaches:
wherein the propeller (“propeller efficiency” Col 11. Ll. 15-16) of the unducted thrust producing apparatus absorbs greater than 75% of a power (Fig 1, η=80%;" the propeller efficiency is maximum if Cp and J are on the line L6" " Col 5 ll.50-51) that corresponds to a takeoff condition of the aircraft (takeoff indicated by “1”, see bottom left of Fig 1).
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Long in view of Long as evidenced by Geyer and Barnett with Otake's structure discussed above in order to achieve “An optimal-efficiency condition of a propeller in a full-power mode has been confirmed in the relationship between the power coefficient Cp and the advance ratio J shown in the graph” Col 4 ll. 45-50
Regarding claim 16, Long in view of Long, as evidenced by Geyer and Barnett, and further in view of Otake teaches the invention as discussed for claim 15.
Long in view of Long, as evidenced by Geyer and Barnett, further in view of Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis. While the specific values of Mach 0.7 and Cp of 2 are explicitly indicated, the relationship between these two values was recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case the Cp of the propeller depending on inter alia, N, as seen on the graph, a variable on the X axis as well, such that the determination of the optimum or workable ranges of said variable, in this case the aircraft travels at a Mach number greater than 0.7 and wherein a cruise propeller power coefficient > 2, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Cp and its relationship with airplane speed, it has been held that the discovery of optimum or workable ranges, in this case adjusting variables to reach an aircraft traveling at a Mach number greater than 0.7 and wherein a non-dimensional power coefficient > 2, by experimentation requiring only routine skill in the art, in this case the ability to search for “An optimal-efficiency condition of a propeller” (Col 4 ll. 45-50), would have been an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A).
Regarding the limitation “the aircraft travels at a Mach number greater than 0.7”, it has been identified as intended use. "[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (emphasis in original). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987)
Regarding claim 17, Long in view of Long, as evidenced by Geyer and Barnett, teaches the invention as discussed for claim 1. Also see rejection of claim 16 under 112(b) above.
Long in view of Long as evidenced by Geyer and Barnett does not explicitly teach the propeller absorbs power for a non-dimensional power coefficient >1 as claimed.
However, Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis.
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Long in view of Long with Otake's structure discussed above in order to achieve “An optimal-efficiency condition of a propeller in a full-power mode has been confirmed in the relationship between the power coefficient Cp and the advance ratio J shown in the graph” Col 4 ll. 45-50
Long in view of Long, as evidenced by Geyer and Barnett, and further in view of Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis. While the specific values of Cp >1 is not explicitly indicated, the relationship between Cp and the values seen in Fig. 1 was recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case the Cp of the propeller depending on inter alia, N, as seen on the graph, a variable on the X axis as well, such that the determination of the optimum or workable ranges of said variable, in this case the aircraft travels at a power coefficient > 1, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Cp and its relationship with airplane speed, it has been held that the discovery of optimum or workable ranges, in this case finding “An optimal-efficiency condition of a propeller” (Col 4 ll. 45-50), by experimentation requiring only routine skill in the art, in this case the ability to search for “An optimal-efficiency condition of a propeller”, would have been an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A).
Regarding claim 26, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 20. Long further teaches:
wherein the unducted thrust producing apparatus is an aircraft engine used by an aircraft (“turbofan, turboshaft, and turboprop engines” [0002]);
Long in view of Long is silent about the propeller absorbing the power as claimed.
However, Otake teaches:
wherein the propeller (“propeller efficiency” Col 11. Ll. 15-16) of the unducted thrust producing apparatus absorbs greater than 75% of a power (Fig 1, η=80%;" the propeller efficiency is maximum if Cp and J are on the line L6" " Col 5 ll.50-51) that corresponds to a takeoff condition of the aircraft (takeoff indicated by “1”, see bottom left of Fig 1).
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Long in view of Long as evidenced by Geyer and Barnett with Otake's structure discussed above in order to achieve “An optimal-efficiency condition of a propeller in a full-power mode has been confirmed in the relationship between the power coefficient Cp and the advance ratio J shown in the graph” Col 4 ll. 45-50
Regarding claim 27, Long in view of Long, as evidenced by Geyer and Barnett, and further in view of Otake teaches the invention as discussed for claim 26.
Long in view of Long, as evidenced by Geyer and Barnett, and further in view of Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis. While the specific values of Mach 0.7 and Cp of 2 are explicitly indicated, the relationship between these two values was recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case the Cp of the propeller depending on inter alia, N, as seen on the graph, a variable on the X axis as well, such that the determination of the optimum or workable ranges of said variable, in this case the aircraft travels at a Mach number greater than 0.7 and wherein a non-dimensional power coefficient > 2, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Cp and its relationship with airplane speed, it has been held that the discovery of optimum or workable ranges, in this case adjusting variables to reach an aircraft traveling at a Mach number greater than 0.7 and wherein a non-dimensional power coefficient > 2, by experimentation requiring only routine skill in the art, in this case the ability to search for “An optimal-efficiency condition of a propeller” (Col 4 ll. 45-50), would have been an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A).
Regarding the limitation “the aircraft travels at a Mach number greater than 0.7”, it has been identified as intended use. "[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (emphasis in original). A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987)
Regarding claim 28, Long in view of Long as evidenced by Geyer and Barnett teaches the invention as discussed for claim 20.
Long in view of Long does not explicitly teach the propeller absorbs power for a non-dimensional power coefficient >1 as claimed.
However, Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis.
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Long in view of Long as evidenced by Geyer and Barnett with Otake's structure discussed above in order to achieve “An optimal-efficiency condition of a propeller in a full-power mode has been confirmed in the relationship between the power coefficient Cp and the advance ratio J shown in the graph” Col 4 ll. 45-50
Long in view of Long, as evidenced by Geyer and Barnett, and further in view of Otake teaches different speeds for an aircraft (inter alia, Fig. 1 X axis, where higher speeds are towards the right of the graph) and its relationship with the power coefficient Cp on the Y axis. While the specific values of Cp >1 is not explicitly indicated, the relationship between Cp and the values seen in Fig. 1 was recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case the Cp of the propeller depending on inter alia, N, as seen on the graph, a variable on the X axis as well, such that the determination of the optimum or workable ranges of said variable, in this case the aircraft travels at a power coefficient > 1, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Cp and its relationship with airplane speed, it has been held that the discovery of optimum or workable ranges, in this case finding “An optimal-efficiency condition of a propeller” (Col 4 ll. 45-50), by experimentation requiring only routine skill in the art, in this case the ability to search for “An optimal-efficiency condition of a propeller”, would have been an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A).
Allowable Subject Matter
Claims 4 and 23 objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Response to Arguments
Applicant’s arguments filed on 1/7/2016 have been considered, and also discussed during the interview completed on 1/20/2026 with applicant’s representative, but they are not persuasive. However, to the extent possible, applicant’s arguments have been addressed in the body of the rejections above, at the appropriate location.
Applicant argues on page 7:
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Examiner’s response: Examiner respectfully disagrees. The drawings do not indicate the first surface and the second surface, as already discussed in the Objection to the drawings. Applicant’s arguments refer to the written description and to the claims, but the elements are not labeled in the drawings and the written description and claims do not clearly reflect the limitations. It is also noted that the amended claim 2 filed on 1/7/2026 changes the “second surface” from being “a second surface of the flow conditioning structure or of the unducted thrust producing apparatus” (where “testing hardware104 (also referred to as a "flow conditioning structure" herein)” [0075] and “the unducted aircraft engine102 is one example of an unducted thrust producing apparatus” [0077], therefore referring to two different elements) to be described as “a second surface of the unducted thrust producing apparatus” (the unducted aircraft engine102 is one example of an unducted thrust producing apparatus [0077]).
Applicant argues on page 11:
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Examiner’s response: Examiner respectfully disagrees. As discussed in the previous rejection as well as above, Long’s structure 16 “guides airflow into turbine engine” [0021], indicating changes in speed and direction in order to achieve a “guiding” process. Additionally, the interference of any body in the “free airstream” (airstream without the interference of structure 16) inherently creates changes in speed (inter alia, at a minimum due to boundary layer and drag effects) and direction (since air can not occupy the same space as the body).
Applicant argues on page 12:
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Examiner’s response: Examiner respectfully disagrees. A turboprop engine without propellers would be described as a gas turbine engine. Merriam-Webster defines turboprop engine as seen in the image below:
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Applicant argues on page 12:
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Examiner’s response: Examiner respectfully disagrees. As clearly taught by Long , “The present disclosure relates generally to performance evaluation, including the evaluation of turbine engine performance. More particularly, the disclosure relates to systems and methods for evaluating the performance of turbine engine systems and subsystems, including, but not limited to, turbofan, turboshaft, and turboprop engines, and industrial gas turbine engines” [0002]; this is also further confirmed in [0022], therefore Long does not effectively prohibits the utilization of the system with a thrust producing propeller (also see comments in the previous responses to arguments above).
Applicant argues on page 13:
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Examiner’s response: similar explanations as discussed above also apply to these claims.
Applicant argues on page 13:
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Examiner’s response: similar explanations as discussed above also apply to these claims.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Roberto T. Igue whose telephone number is (303)297-4389. The examiner can normally be reached Monday-Friday 7:30-4:30 PT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Phutthiwat Wongwian can be reached at (571) 270-5426. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ROBERTO TOSHIHARU IGUE/Examiner, Art Unit 3741
/PHUTTHIWAT WONGWIAN/Supervisory Patent Examiner, Art Unit 3741
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