# US 12,180,850 B2 · Method for detecting a possible fuel leak in an oil circuit of an aircraft engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,850 B2 - Document ID: US12180850B2 - Status: Granted - Kind: B2 - Application number: 17/435,460 - Filed: 2020-03-05 - Published: 2022-06-09 - Granted: 2024-12-31 - Earliest claimed: 2019-03-15 - Assignees: Safran Aircraft Engines - Applicants: Safran Aircraft Engines - Inventors: Sébastien Jean Fernand Deneuve; Ruben Abraham Elbaz; Alrick Patrick Michel Jacques Verrier; Christophe Mathedarre; Nicolas Andréa Fabbro - Web page: https://patentgrep.com/patent/US12180850B2 ## CPC - F01D 21/003: {Arrangements for testing or measuring (for measuring vibrations G01H)} - F01D 25/18: Lubricating arrangements (of machines or engines in general F01M) - B64D 45/00: Aircraft indicators or protectors not otherwise provided for - B64D 2045/0085: {Devices for aircraft health monitoring, e.g. monitoring flutter or vibration} - F05D 2260/80: Diagnostics - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract The invention relates to a method for detecting a possible fuel leak into an oil circuit of an aircraft engine, the aircraft including at least one pair of identical engines equipped with respective oil circuits, the pair of engines being associated with at least one quadruplet of measurements previously acquired in a measurement time during the operation of the engines of the pair and corresponding to a measurement of pressure and a measurement of temperature of the fluid contained in each of the oil circuits of the engines of the pair. ## Claims ### Claim 1 A method for detecting a possible fuel leak into an oil circuit of an aircraft engine, said aircraft including at least one pair of identical engines equipped with respective oil circuits, said pair of engines being associated with at least one quadruplet of measurements previously acquired in a measurement time during an operation of the engines of the pair and corresponding to a measurement of pressure and a measurement of temperature of a fluid contained in each of the oil circuits of the engines of the pair, the detection method including: a step of determining a quantity Q representative of a possible operating difference between the engines of the pair, based on the measurement quadruplet, a step of comparing the quantity Q with a previously determined threshold value, so as to obtain a comparison result, a step of detecting a possible fuel leak into the oil circuit of one of the engines of the pair, based on the comparison result, a step of identifying a faulty engine among the engines of the pair, said identification step including comparing the measurements of pressure and/or comparing the measurements of temperature of the quadruplet, associated respectively with the engines of the pair; and identifying the faulty engine based on said comparison of the measurements of pressure and/or said comparison of the measurements of temperature, such that a first engine of the pair of engines is identified as the faulty engine when either (i) a first temperature of the quadruplet of measurements associated with the first engine is greater than a second temperature of the quadruplet of measurements associated with a second engine of the pair of engines, or (ii) a first pressure of the quadruplet of measurements associated with the first engine is less than a second pressure of the quadruplet of measurements associated with the second engine, a step of transmitting an alarm message in a text format to a display means, said alarm message includes an identifier of the identified faulty engine, wherein an operator on the ground, based on the alarm message, is configured to implement a maintenance operation to repair the identified faulty engine. ### Claim 2 (depends on 1) The method according to claim 1, wherein the step of determining the quantity Q includes: calculation of a first quantity Q1 representative of a pressure gap between the two engines, based on the measurements of pressure of the quadruplet, calculation of a second quantity Q2 representative of a gap in temperature between the two engines, based on the measurements of temperature of the quadruplet, calculation of the quantity Q based on the quantities Q1 and Q2. ### Claim 3 (depends on 2) The method according to claim 2, wherein the quantity Q is calculated according to the following formula: Q=√{square root over (Q12+Q22)}, Q1 is calculated equal to the difference between the measurements of pressure of the quadruplet, Q2 is calculated equal to the difference between the measurements of temperature of the quadruplet. ### Claim 4 (depends on 1) The method according to claim 1, including, after the step of determining the quantity Q and before the comparison step, a step of updating the quantity Q in which the updated quantity Q corresponds to an absolute value of the quantity Q previously determined. ### Claim 5 (depends on 1) The method according to claim 1, wherein each engine of the pair is also associated with at least two measurements of fluid volume contained in the oil circuit of said engine of the pair and previously acquired in two distinct respective measurement times, one measurement time prior to the takeoff of the aircraft and one measurement time subsequent to the landing of the aircraft, said method including, for at least one engine of the pair: a step of determining a gap between the two measurements of fluid volume associated with said engine, a step of comparing the gap with a threshold value determined based on a theoretical average oil consumption of the faulty engine and on a duration separating said distinct measurement times, and, following said identification step: a step of possible confirmation, based on the result of the comparison of the gap with the threshold value, of the identity of the engine identified as faulty. ### Claim 6 (depends on 1) The method according to claim 1, wherein several measurement quadruplets are considered, at least the steps of determining a quantity Q, of comparing the quantity Q with a threshold value and of detecting a possible leak being iterated for each of said measurement quadruplets. ### Claim 7 (depends on 1) The method according to claim 1, wherein the aircraft includes several pairs of identical engines, at least the steps of determining a quantity Q, of comparing the quantity Q with a threshold value and of detecting a possible leak being iterated for each of said pairs. ### Claim 8 (depends on 1) A non-transitory computer-readable storage medium including a set of program code instructions which, when they are executed by a processor, configure said processor to implement a detection method according to claim 1. ### Claim 9 (depends on 8) The non-transitory computer readable storage medium, on which is recorded a computer program including the set of program instructions according to claim 8. ### Claim 10 A processing device for detecting a possible fuel leak into an oil circuit of an aircraft engine, said aircraft including at least one pair of identical engines equipped with respective oil circuits, said pair of engines being associated with at least one quadruplet of measurements previously acquired at a same measurement instant during an operation of the engines of the pair and corresponding to a measurement of pressure and a measurement of temperature of a fluid contained in each of the oil circuits of the engines of the pair, the processing device including: a determination module, configured to determine a quantity Q representative of a possible operating difference between the engines of the pair, based on the measurement quadruplet, a comparison module, configured to compare the quantity Q with a previously determined threshold value, so as to obtain a comparison result, a detection module, configured to detect a possible fuel leak into the oil circuit of one of the engines of the pair, based on the comparison result, wherein the detection module is further configured to identify a faulty engine among the engines of the pair by comparing the measurements of pressure and/or comparing the measurements of temperature of the quadruplet, associated respectively with the engines of the pair; and identifying the faulty engine based on said comparison of the measurements of pressure and/or said comparison of the measurements of temperature such that a first engine of the pair of engines is identified as the faulty engine when either (i) a first temperature of the quadruplet of measurements associated with the first engine is greater than a second temperature of the quadruplet of measurements associated with a second engine of the pair of engines, or (ii) a first pressure of the quadruplet of measurements associated with the first engine is less than a second pressure of the quadruplet of measurements associated with the second engine, a display means configured to display a transmitted alarm message, wherein the alarm message includes an identifier of the identified faulty engine, and wherein an operator on the ground, based on the alarm message, is configured to implement a maintenance operation to repair the identified faulty engine. ### Claim 11 (depends on 10) The device according to claim 10, each engine of the pair also being associated with at least two measurements of fluid volume contained in the oil circuit of said engine of the pair and previously acquired in two respective distinct measurement times during the operation of the aircraft, a measurement time prior to the takeoff of the aircraft and a measurement time subsequent to the landing of the aircraft, said device including: a determination module, configured to determine a gap between the two measurements of fluid volume associated with one engine of the pair, a comparison module, configured to compare the gap with a threshold value determined based on a theoretical average oil consumption of the faulty engine and on a duration separating said distinct measurement times, a confirmation module, configured to confirm, based on the result of comparing the gap with the threshold value, the identity of the engine identified as faulty. ### Claim 12 (depends on 10) A system for detecting a possible fuel leak into an oil circuit of an aircraft engine, said aircraft including at least one pair of identical engines equipped with respective oil circuits, said detection system including: acquisition means configured to acquire at least one measurement quadruplet in one measurement time during the operation of the engines of the pair and corresponding to a measurement of pressure and a measurement of temperature of the fluid contained in each of the oil circuits of the engines of the pair, a processing device conforming to claim 10, means of communicating the measurement quadruplet to the processing device. ### Claim 13 (depends on 12) The system according to claim 12, said acquisition means also being configured to acquire, for each engine of the pair, at least two measurements of fluid volume contained in the oil circuit of said engine in two distinct measurement times during the operation of the aircraft, one measurement time prior to the takeoff of the aircraft and one measurement time subsequent to the landing of the aircraft, said processing device including: an identification module configured, when a leak is detected, to: compare the measurements of pressure and/or the measurements of temperature of the quadruplet associated respectively with the engines of the pair, identify a faulty engine based on said comparison of the measurements of pressure and/or said comparison of the measurements of temperature, a determination module, configured to determine a gap between the two measurements of fluid volume associated with one engine of the pair, a comparison module, configured to compare the gap with a threshold value determined based on a theoretical average oil consumption of the faulty engine and on a duration separating said distinct measurement times, and a confirmation module, configured to confirm, based on the result of comparing the gap with the threshold value, the identity of the engine identified as faulty, and the communication means also being configured to transmit the measurements of the fluid volume to the processing device. ### Claim 14 (depends on 12) An aircraft including a detection system according to claim 12.