# US 10,309,317 B2 · Air turbine starter pressure monitor system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,317 B2 - Document ID: US10309317B2 - Status: Granted - Kind: B2 - Application number: 14/306,870 - Filed: 2014-06-17 - Published: 2014-12-25 - Granted: 2019-06-04 - Earliest claimed: 2013-06-21 - Assignees: Hamilton Sundstrand Corporation - Applicants: United Technologies Corporation - Inventors: John T. Pech; W. Dean Kavalkovich - Web page: https://patentgrep.com/patent/US10309317B2 ## CPC - F02C 7/277: the starter being a {separate} turbine - F02C 7/268: Starting drives for the rotor {, acting directly on the rotor of the gas turbine to be started} - F05D 2260/80: Diagnostics - F05D 2260/81: Modelling or simulation - F05D 2260/85: Starting - F05D 2270/00: Control - F05D 2270/301: Pressure - F05D 2270/304: Spool rotational speed - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A method of monitoring a gas turbine engine start system includes monitoring a pressure in a starter air duct in communication with a starter air valve which is in communication with an air turbine starter (ATS); identifying an expected transient pressure response in the starter air duct; and identifying the starter air valve as degraded if the expected transient pressure response does not occur after an open command to the starter air valve. ## Claims ### Claim 1 A method of monitoring a gas turbine engine start system, the method comprising: monitoring a pressure of air in a starter air duct that is upstream of and in communication with a starter air valve which is in communication with an Air Turbine Starter (ATS), wherein the air in the starter air duct is pressurized; identifying an expected transient pressure response of the pressure of the air in the starter air duct upstream of the starter air valve; and identifying the starter air valve as degraded if the expected transient pressure response of the air upstream of the starter air valve does not occur after an open command to the starter air valve by comparing the transient response to a stored nominal response. ### Claim 2 (depends on 1) The method as recited in claim 1, further comprising: monitoring a rotational speed of the Air Turbine Starter (ATS); and identifying the Air Turbine Starter (ATS) as degraded if the rotational speed of the Air Turbine Starter (ATS) does not increase after the open command. ### Claim 3 (depends on 1) The method as recited in claim 1, further comprising: monitoring a rotational speed of a gas turbine engine selectively driven by the Air Turbine Starter (ATS); and identifying a starter shaft of the Air Turbine Starter (ATS) as degraded if the rotational speed of the gas turbine engine does not increase after the open command. ### Claim 4 (depends on 1) The method as recited in claim 1, further comprising: monitoring a rotational speed of the Air Turbine Starter (ATS); monitoring a rotational speed of a gas turbine engine selectively driven by the Air Turbine Starter (ATS); identifying the Air Turbine Starter (ATS) as degraded if the rotational speed of the Air Turbine Starter (ATS) does not increase after the open command; and identifying a starter shaft of the Air Turbine Starter (ATS) as degraded if the rotational speed of the gas turbine engine does not increase after the open command. ### Claim 5 (depends on 1) The method as recited in claim 1, further comprising sending the pressurized air from an auxiliary power unit to the Air Turbine Starter (ATS) through the starter air duct and the starter air valve. ### Claim 6 (depends on 1) The method as recited in claim 1, further comprising sending the pressurized air from a gas turbine engine to the Air Turbine Starter (ATS) through the starter air duct and the starter air valve. ### Claim 7 A method of monitoring a gas turbine engine start system, the method comprising: monitoring a pressure drop within a starter air duct upstream of a starter air valve in communication with an Air Turbine Starter (ATS), wherein air in the starter air duct is pressurized before the monitoring; and identifying the starter air valve as degraded if the monitored pressure drop upstream of the starter air valve within the starter air duct is less than a stored predetermined pressure drop after an open command is provided to the starter air valve. ### Claim 8 (depends on 7) The method as recited in claim 7, wherein the identifying further comprises measuring a pressure within the starter air duct upstream of the starter air valve to determine an immediate pressure response profile in response to the open command to the starter air valve. ### Claim 9 (depends on 7) The method as recited in claim 7, wherein the identifying further comprises measuring a pressure within the starter air duct upstream of the starter air valve to determine an immediate pressure response profile is within a tolerance band in response to the open command to the starter air valve. ### Claim 10 (depends on 9) The method as recited in claim 9, wherein said tolerance band is determined from a multiple of engine starts. ### Claim 11 (depends on 9) The method as recited in claim 9, wherein said tolerance band is predetermined. ### Claim 12 (depends on 7) The method as recited in claim 7, further comprising: monitoring a rotational speed of the Air Turbine Starter (ATS); and identifying the Air Turbine Starter (ATS) as degraded if the rotational speed of the Air Turbine Starter (AT S) does not increase in response to the open command to the starter air valve and the pressure drop is less than said predetermined pressure drop. ### Claim 13 (depends on 12) The method as recited in claim 12, further comprising: monitoring a rotational speed of a gas turbine engine selectively driven by the Air Turbine Starter (ATS); and identifying a starter shaft of the Air Turbine Starter (ATS) as degraded if the rotational speed of the gas turbine engine does not increase in response to an open command to the starter air valve, if the rotational speed of the Air Turbine Starter (ATS) does not increase in response to the open command to the starter air valve and if the pressure drop is less than the predetermined pressure drop.