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 .
Election/Restrictions
Applicant’s election without traverse of Species A Claims 1-2 and 5-10 in the reply filed on 3rd February 2026 is acknowledged.
Claims 3-4 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species.
Claim Objections
Claims 9-10 are objected to because of the following informalities:
In claim 9 line 4, “…wherein a transition process…” should read “…wherein the transition process…” as positively recited in line 2.
In claim 9 line 11, “…wherein a transition process…” should read “…wherein the transition process…” as positively recited in line 2.
In claim 9 line 14, “…configuring the tilt rates of the four tilting rotors, the thrust distribution…” should read “…configuring tilt rates of the four tilting rotors, thrust distribution…” so that there is a sufficient antecedent basis for the limitation in the claim.
In claim 10 line 5, “…when the wind speed…” should read “… when a wind speed…” so that there is a sufficient antecedent basis for the limitation in the claim.
Appropriate correction is required.
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.
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.
Claim(s) 1-2 and 5-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Qi (CN 217416106) in view of Baharav et al. (US 2022/0009626) and Quenzler (US 3,081,964).
Regarding claim 1, Qi ‘106 teaches (figures 1-6) a vertical take-off and landing aircraft, comprising:
a fuselage (2), wherein both sides of the fuselage (2) are provided with wings (1) (English Translation; Pg. 4 Para 2);
two tilting rotors/first propellers (4s), provided at a front sides of the wings on both sides and two fixed rotors/third propellers (6s) provided at rear sides of the wings on both sides (clearly shown in the figure below) (English Translation; Pg. 4 Para 4);
two tilting rotors/first propellers (4s), provided at outer sides of the tilting rotors/first propellers (4s) at both sides of the fuselage, and provided at the front sides of the wings (1) and two fixed rotors/second propellers (5s) provided at outer sides of the tilting rotors/first propellers at both sides of the fuselage, and provided at the rear sides of the wings (1) (clearly shown in the figure below) (English Translation; Pg. 4 Para 4);
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but it is silent about the vertical take-off and landing aircraft, comprising:
two fixed rotors/third propellers (6s) as two tilting rotors;
two tilting rotors, provided at outer sides of the tilting rotors as two fixed rotors.
Baharav et al. ‘626 teaches (figures 1-2) air vehicle (10) comprising an airframe (100) and a propulsion system (500) wherein the propulsion system (500) comprises a first set (600) of four first propulsion units/fixed rotors (650) wherein the four first propulsion units/fixed rotors (650) are fixedly mounted to the booms (400) and a second set (700) of four second propulsion units/tilting rotors (750) (Para 0128, 0164; first propulsion units/fixed rotors are attached to the wing via booms; second propulsion units/tilting rotors/tilting rotors are not coupled to the boom).
Therefore, 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 Qi ‘106 to incorporate the teachings of Baharav et al. ‘626 to configure the vertical take-off and landing aircraft, wherein two fixed rotors are attached to the wing via boom and tilt rotors are not coupled to the boom. This results in the vertical take-off and landing aircraft, comprising:
two fixed rotors/third propellers (6s) as two tilting rotors;
two tilting rotors, provided at outer sides of the tilting rotors as two fixed rotors.
One of ordinary skill in art would recognize that doing so would enhance flight aerodynamics and stability by creating a thrust balance from two fixed rotors on a boom during vertical flights.
Modified Qi ‘106 is silent about the vertical take-off and landing aircraft:
wherein both sides of the fuselage are provided with wings symmetrically;
wherein positions of the four tilting rotors, rotation directions of the four tilting rotors and installation angles of the four tilting rotors are pairwise correspondence and symmetrical about a longitudinal symmetry plane of the fuselage;
a spacing between two tilting rotors at the front sides of the wings is A, a spacing between the two tilting rotors at the rear sides of the wings is B, and a deviation between A and B is less than or equal to 0.2*(A+B)/2;
wherein positions of the four fixed rotors, rotation directions of the four fixed rotors and installation angles of the four fixed rotors are pairwise correspondence and symmetrical about the longitudinal symmetry plane;
a spacing between two fixed rotors at the front sides of the wings is C, a spacing between two fixed rotors on the rear sides of the wings is D, and a deviation between C and D is less than or equal to 0.05*(C+D)/2;
wherein, in vertical take-off and landing state, projections of the four tilting rotors on a horizontal plane are pairwise correspondence and centrally symmetrical about a center of gravity of the vertical take-off and landing aircraft within a first setting range, and positions are symmetrical about a vertical plane passing through the center of gravity and perpendicular to the longitudinal symmetry plane;
a spacing of horizontal projections of the tilting rotors along a longitudinal direction is M;
the first setting range is that a longitudinal deviation between an intersection of diagonal lines of the horizontal projections of the four tilting rotors and a horizontal projection of the center of gravity is less than or equal to 0.1 *M;
projection centers of the four fixed rotors on the horizontal plane are pairwise correspondence and centrally symmetrical about the center of gravity within a second setting range, and positions are symmetrical about the vertical plane;
a longitudinal spacing of horizontal projections of the fixed rotors is N, and the second setting range is that a longitudinal deviation between an intersection of diagonal lines of the horizontal projections of the four fixed rotors and the horizontal projection of the center of gravity is less than or equal to 0.1 *N.
Quenzler ‘964 teaches (figures 1-2) arranging the engine pairs suspended from the wings symmetrically at opposite sides of the longitudinal axis of the airplane, arranging the wings symmetrically fore and aft of the center of gravity of the airplane and arranging the engine units disposed fore and aft of the center of gravity in symmetrical fashion, the thrust line of each engine when directed substantially vertically will be disposed at a side of the center of gravity of the airplane opposite the substantially vertical thrust line of another engine in a vertical plane extending diagonally of the airplane's longitudinal axis through the center of gravity and the two engines in any such vertical plane will rotate oppositely to balance their torques (Col. & lines 28-50).
Therefore, 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 Qi ‘106 to incorporate the teachings of Quenzler ‘964 to configure, the vertical take-off and landing aircraft:
wherein both sides of the fuselage are provided with wings symmetrically;
wherein positions of the four tilting rotors, rotation directions of the four tilting rotors and installation angles of the four tilting rotors are pairwise correspondence and symmetrical about a longitudinal symmetry plane of the fuselage (rotors are symmetrically at opposite sides of the longitudinal axis and rotate oppositely/symmetrically to balance torques);
a spacing between two tilting rotors at the front sides of the wings is A, a spacing between the two tilting rotors at the rear sides of the wings is B, and a deviation between A and B is less than or equal to 0.2*(A+B)/2 (deviation is zero as rotors disposed fore and aft of the center of gravity is in symmetrical fashion);
wherein positions of the four fixed rotors, rotation directions of the four fixed rotors and installation angles of the four fixed rotors are pairwise correspondence and symmetrical about the longitudinal symmetry plane (rotors are symmetrically at opposite sides of the longitudinal axis and rotate oppositely/symmetrically to balance torques);
a spacing between two fixed rotors at the front sides of the wings is C, a spacing between two fixed rotors on the rear sides of the wings is D, and a deviation between C and D is less than or equal to 0.05*(C+D)/2 (deviation is zero as rotors disposed fore and aft of the center of gravity is in symmetrical fashion);
wherein, in vertical take-off and landing state, projections of the four tilting rotors on a horizontal plane are pairwise correspondence and centrally symmetrical about a center of gravity of the vertical take-off and landing aircraft within a first setting range, and positions are symmetrical about a vertical plane passing through the center of gravity and perpendicular to the longitudinal symmetry plane;
a spacing of horizontal projections of the tilting rotors along a longitudinal direction is M;
the first setting range is that a longitudinal deviation between an intersection of diagonal lines of the horizontal projections of the four tilting rotors and a horizontal projection of the center of gravity is less than or equal to 0.1 *M (diagonal intersection lines extends through the center of gravity);
projection centers of the four fixed rotors on the horizontal plane are pairwise correspondence and centrally symmetrical about the center of gravity within a second setting range, and positions are symmetrical about the vertical plane;
a longitudinal spacing of horizontal projections of the fixed rotors is N, and the second setting range is that a longitudinal deviation between an intersection of diagonal lines of the horizontal projections of the four fixed rotors and the horizontal projection of the center of gravity is less than or equal to 0.1 *N (diagonal intersection lines extends through the center of gravity).
One of ordinary skill in art would recognize that doing so would enhance stability during flights.
Regarding claim 2, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft wherein the tilting rotor at the front side of the wing (1) are provided at the wing (1) by a wing boom (clearly shown in the figure above).
Regarding claim 5, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft wherein an empennage is provide at a tail (3) of the fuselage, and the empennage is a V-shaped (clearly seen in figures 1-2) (English Translation Pg. 4 Para 3).
Regarding claim 6, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft wherein the two tilting rotors are provided at the empennage and configured to provide forward thrust for the aircraft to fly forward, and are configured to tilt upward to provide vertical thrust in response to the aircraft being in a vertical take-off and landing state (as modified by Baharav et al. ‘626).
Regarding claim 7, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft wherein an empennage is a V-shaped tail, and the two tilting rotors at the rear side of the wing are respectively provided at tips of the tail on both sides of an upper part of the empennage (English Translation Pg. 4 Para 3).
Regarding claim 8, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft wherein the wings (1) on both sides of the fuselage are provided with wing booms (clearly seen in figures 1-5), and the four fixed rotors are symmetrically provided at the wing booms on both sides of the fuselage and are respectively provided at the front sides of the wings and the rear sides of the wings (as modified by Baharav et al. ‘626).
Regarding claim 9, modified Qi ‘106 teaches (figures 1-6) the vertical take-off and landing aircraft comprising: following transition process from vertical take-off to horizontal flight,
wherein the transition process from the vertical take-off to the horizontal flight/cruising stage comprises:
tilting, by a powered system/tilting mechanism (7), the four tilting rotors forward according to a forward flight command (English Translation Pg. 6 Para 1-2, 14; tilting mechanism is activated based on a flight command); and
configuring tilt rates of the four tilting rotors, thrust distribution of the four tilting rotors and the four fixed rotors according to a climb command, thereby controlling rate of claim of the vertical take-off and landing aircraft and angle of claim of the vertical take-off and landing aircraft (English Translation Pg. 6 Para 1-2, 14).
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Qi (CN 217416106), Baharav et al. (US 2022/0009626) and Quenzler (US 3,081,964) as applied to claim 9 above, and further in view of Lind et al. (US 2018/0251215).
Regarding claim 10, modified Qi ‘106 teaches (figures 1-6) the method according to claim 9 but it is silent about the method further comprising an unintentional spin or stall recovery process and/or a crosswind response process,
wherein the unintentional spin or stall recovery process comprises: starting the four fixed rotors to assist in attitude control, thereby recovering from the spin or stall condition; and
the crosswind response process comprises: when a wind speed exceeds a preset threshold,
assisting yaw control by differential thrust of the four tilting rotors to counteract the crosswind.
Lind et al. ‘215 teaches (figures 1-10) a bimodal propeller aircraft comprising four hover propellers (134, 136, 138, 140), and four cruise propellers (126, 128, 130, 132) wherein hover propellers are turned on when the aircraft’s airspeed falls below a threshold level to improve stall recovery (Para 0048).
Therefore, 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 Qi ‘106 to incorporate the teachings of Lind et al. ‘215 to configure the method further comprising an unintentional spin or stall recovery process,
wherein the unintentional spin or stall recovery process comprises: starting the four fixed rotors to assist in attitude control, thereby recovering from the spin or stall condition.
One of ordinary skill in art would recognize that doing so would improve stall recovery (Para 0048).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ASHESH DANGOL whose telephone number is (303)297-4455. The examiner can normally be reached Monday-Friday 0730-0530 MT.
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/ASHESH DANGOL/Primary Examiner, Art Unit 3642