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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 04/20/2026 has been entered on 08/18/2026.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 21-29 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Regarding claim 21 and its dependents, recitation “determine a flow over area ratio based on one or more of the first fuel pressure, the second fuel pressure, the pressure differential, and the state of the gaseous fuel flow, wherein the flow over area ratio is calculated as a function of the first fuel pressure when the state of the gaseous fuel flow is sonic, and as a function of the first fuel pressure, the second fuel pressure, and the pressure differential when the state or the gaseous fuel flow is subsonic; … determine a fuel flow rate of the gaseous fuel flow to obtain the desired power output of the aircraft engine by multiplying the flow over area ratio by the effective area of the fuel metering valve” contains limitation that is not supported by the specification because:
i) the specification does NOT provide a definition for term “a flow over area ratio” and from p. 15, l. 16 to p. 16, l. 22 and Fig. 3, specification discloses a sonic flow rate Wf/Afmy is calculated as a function of the first fuel pressure P1 and fuel temperature T1, where fmv effective area Afmv is calculated by reading the position sensor feedback signal 149, and required fuel flow is then calculated using Wf = (Wf/Afmv) X Afmv, and a subsonic flow rate Wf/Afmy is calculated as a function of the first fuel pressure P1, the second fuel pressure P2, the delta pressure, and the fuel temperature T1, where fmv effective area Afmv is calculated by reading the position sensor feedback signal 149, and required fuel flow is then calculated using Wf = (Wf/Afmv) X Afmv, and thus, the specification does NOT support determine a flow over area ratio based on one or more of the first fuel pressure, the second fuel pressure, the pressure differential, and the state of the gaseous fuel flow, wherein the flow over area ratio is calculated as a function of the first fuel pressure when the state of the gaseous fuel flow is sonic, and as a function of the first fuel pressure, the second fuel pressure, and the pressure differential when the state or the gaseous fuel flow is subsonic; … determine a fuel flow rate of the gaseous fuel flow to obtain the desired power output of the aircraft engine by multiplying the flow over area ratio by the effective area of the fuel metering valve;
ii) it is further noted, “When examining computer-implemented functional claims, examiners should determine whether the specification discloses the computer and the algorithm (e.g., the necessary steps and/or flowcharts) that perform the claimed function in sufficient detail such that one of ordinary skill in the art can reasonably conclude that the inventor possessed the claimed subject matter at the time of filing. An algorithm is defined, for example, as "a finite sequence of steps for solving a logical or mathematical problem or performing a task." Microsoft Computer Dictionary (5th ed., 2002). Applicant may "express that algorithm in any understandable terms including as a mathematical formula, in prose, or as a flow chart, or in any other manner that provides sufficient structure." Finisar Corp. v. DirecTV Grp., Inc., 523 F.3d 1323, 1340, 86 USPQ2d 1609, 1623 (Fed. Cir. 2008) (internal citation omitted). It is not enough that one skilled in the art could write a program to achieve the claimed function because the specification must explain how the inventor intends to achieve the claimed function to satisfy the written description requirement. See, e.g., Vasudevan Software, Inc. v. MicroStrategy, Inc., 782 F.3d 671, 681-683, 114 USPQ2d 1349, 1356, 1357 (Fed. Cir. 2015) (reversing and remanding the district court’s grant of summary judgment of invalidity for lack of adequate written description where there were genuine issues of material fact regarding "whether the specification show[ed] possession by the inventor of how accessing disparate databases is achieved")”, MPEP 2161.01(I), in this case, the specification does not provide what the claimed function/mathematical formula is to determine/calculate the claimed flow over area ratio. (note: Miller 20050021213, Ohmi 20040204794, and Fujii 7756626 discloses the actual function(s) that is used to determine/calculate the fuel flow rate);
iii) therefore, the recitation is rejected as new matter and lacking written description.
The same new matter and lacking written description rejection is also applied to the limitation, “determine the flow over area ratio based on one or more of the first fuel pressure, the second fuel pressure, the pressure differential, the state of the gaseous fuel flow, and the fuel temperature, wherein the flow over area ratio is calculated as a function of the first fuel pressure and the fuel temperature when the state of the gaseous fuel flow is sonic, and as a function of the first fuel pressure, the second fuel pressure, the pressure differential, and the fuel temperature when the state of the gaseous fuel flow is subsonic”, of claim 22 and its dependents.
Response to Arguments
Applicant's arguments filed 04/20/2026 and entered 08/18/2026 have been fully considered.
With respective to the 112a written description rejection for claims 21-22, Applicant’s argument, on p. 4, “In particular, the specification discloses, at paragraph [0044], that when the flow is sonic, "the method includes calculating a sonic flow rate (W/Afmv) as a function of the first fuel pressure (P1) in the fuel feed conduit 122 upstream of the electronic metering valve 146 and the fuel temperature (T1)." The specification further discloses, at paragraph [0046], that when the flow is subsonic, "the method includes calculating a subsonic flow rate (W/Afmv) as a function of the first fuel pressure (P1) in the fuel feed conduit 122 upstream of the electronic metering valve 146, the second fuel pressure (P2) in the fuel feed conduit 122 downstream of the electronic metering valve 146, the delta pressure 161 (e.g. the difference in pressure between the combustor pressure P3 and the second fuel pressure P2), and the first fuel temperature (T1)." Figure 3 provides a detailed flowchart showing the complete decision logic and calculation steps, including the determination of whether the flow is sonic or subsonic (based on P2/P1 < 0.5283), the calculation of the flow over area ratio as a function of the appropriate pressure and temperature parameters, the calculation of the effective area from the LVDT sensor feedback, and the determination of the required fuel flow by multiplying the flow over area ratio by the effective area. This constitutes a complete algorithm disclosed in sufficient detail”.
Said argument is not moot because it does not apply to the new ground rejection issued to term “a flow over area ratio” in the current office action, neccesitatted to amendment, see detailed rejection above.
Conclusion
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/JINGCHEN LIU/Examiner, Art Unit 3741
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