Patent Description:
In high temperature engine coolers, localized differences in temperature gradients on engine cooler parts result in uneven distribution of thermal stresses and loads on those parts, over extended operation. The uneven distribution of thermal stresses and loads can cause localized thermal fatigue cracks from the engine coolers being subjected to repeated high thermal gradients. Such fatigue cracks often limit the useful service life of the engine coolers. Engine coolers are disclosed in <CIT>, <CIT> and <CIT>. Specifically, <CIT> discloses an arrangement involving the reduction of thermal stress on a heat exchanger comprising two heat exchange portions such that the life of the heat exchanger can be extended. <CIT> discloses a plate-fin heat exchanger comprising a heat exchanger core, a hot medium path and a cold medium path. <CIT> discloses individual heat exchangers that can be pivoted around an axis of rotation or linearly displaced for cleaning purposes.

A method of tracking an engine cooler in an aircraft is provided as defined by claim <NUM>.

The present summary is provided only by way of example, and not limitation. Other aspects of the present disclosure will be appreciated in view of the entirety of the present disclosure, including the entire text, claims, and accompanying figures.

While the above-identified figures set forth one or more embodiments of the present disclosure, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents embodiments by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope of the invention as defined by the claims. The figures may not be drawn to scale, and applications and embodiments of the present disclosure may include features and components not specifically shown in the drawings.

Localized differences in temperature gradients on engine cooler parts can result in uneven distribution of thermal stresses and loads on those parts, over extended operation. To ameliorate those stresses, prognostic health management ("PHM") integrating data from 2D matrix or radio-frequency identification ("RFID") tags, human-readable placards, and aircraft maintenance databases ("AMDs") for a given engine cooler is used to facilitate tracking of the engine cooler's orientation and expected accumulated thermal stresses. Due to a symmetric design of the engine cooler, an orientation of the engine cooler can be adjusted (e.g. rotated and/or reversed) at suitable maintenance intervals based on this data to minimize local thermal fatigue and extend the serve life of the engine cooler.

<FIG> is a perspective view of environmental control system assembly <NUM> ("ECS assembly <NUM>") and shows centerline axis <NUM> and first ECS pack 14A with first fan inlet diffuser housing 16A ("FIDH 16A"), first air cycle machine 18A ("ACM 18A"), first heat exchanger 20A, first bleed inlet port 22A, first RAM inlet port 24A, and first RAM outlet port 26A. <FIG> also shows second ECS pack 14B with second FIDH 16B, second ACM 18B second heat exchanger 20B, second bleed inlet port 22B, second RAM inlet port 24B, and second RAM outlet port 26B.

As discussed herein, the structure and operation of second ECS pack 14B generally parallels that of first ECS pack 14A, discussed above. For example, regarding second ECS pack 14B and its components, second ECS pack 14B operates in the same or substantially the same manner as that of first ECS pack 14A and its components. Accordingly, the following description of first ECS pack 14A and its components also extends to second ECS pack 14B and its corollary components (e.g., first FIDH 16A to second FIDH 14B, etc.). As such, because the description of first ECS pack 14A and its components can be used to describe second ECS pack 14B and its components, a full description of second ECS pack 14B is herein omitted in the interest of avoiding undue repetition. The same or similar comparison also extends to the descriptions of <FIG> provided herein.

ECS assembly <NUM> is an assembly of first and second ECS packs 14A and 14B. Centerline axis <NUM> is a major axis of the aircraft and is disposed at a midpoint between first and second ECS packs 14A and 14B. First ECS pack 14A is an environmental control system. In this non-limiting embodiment, first ECS pack 14A is an environmental control system for an aircraft. First FIDH 16A is a fan inlet diffuser housing. First ACM 18A is an air cycle machine. First heat exchanger 20A is a heat exchanger with a plurality of fins for transferring thermal energy between the fins and a fluid (e.g., air). First bleed inlet port 22A is an inlet port for bleed air. First RAM inlet port 24A is an inlet port for ram air. First RAM outlet port 26A is an outlet port for RAM air.

ECS assembly <NUM> is mounted within a portion of an aircraft. First ECS pack 14A is fluidly connected to numerous fluid sources such as an engine, an auxiliary power unit, a source of ambient air, a cabin, a cockpit, and/or a source of ram air of the aircraft. First FIDH 16A is mounted to a side of first heat exchanger 20A and to first ACM 18A. In other illustrative embodiments, first FIDH 16A can be replaced with another component or removed all together from first ECS pack 14A. First ACM 18A is fluidly connected to first FIDH 16A. First heat exchanger 20A is mounted to and fluidly connected with first FIDH 16A. First bleed inlet port 22A is mounted and fluidly connected to an end of first heat exchanger 20A. First RAM inlet port 24A is mounted to and fluidly connected with a side-face of first heat exchanger 20A. First RAM outlet port 26A is mounted and fluidly connected to an end of FIDH 16A.

ECS assembly <NUM> with first ECS pack 14A and second ECS pack 14B controls and manages the transfer of thermal energy and pressures among the different sources of air throughout the aircraft. First FIDH 16A receives and transfers air away from first heat exchanger 20A. First ACM 18A assists with changes to the pressure, temperature, and/or humidity of air passing through first ACM 18A. First heat exchanger 20A conditions a flow of air passing through first heat exchanger 20A. First bleed inlet port 22A guides and transfers a flow of bleed air into first heat exchanger 20A. First RAM inlet port 24A receives a flow of ram air from ambient and transfers that air to first heat exchanger 20A. First RAM outlet port 26A transfers a flow of air out of FIDH 16A.

Here, first heat exchanger 20A and second heat exchanger 20B are symmetric about centerline axis <NUM> such that both first heat exchanger 20A and second heat exchanger 20B can be rotated about centerline axis <NUM> and installed in the other's initial position. For example, first heat exchanger 20A can be removed from first ECS pack 14A, rotated <NUM> ° about centerline axis <NUM>, and reinstalled into second ECS pack 14B. Likewise, second heat exchanger 20B can be removed from second ECS pack 14B, rotated <NUM>° about centerline axis <NUM>, and reinstalled into first ECS pack 14A. The subsequent descriptions and methodology discussed with respect to <FIG> can also be applied to ECS assembly <NUM> in order to determine when first heat exchanger 20A and/or second heat exchanger 20B need to or should be flipped/rotated and installed in a new position.

<FIG> is a perspective view of engine cooler <NUM> and shows rotational axis <NUM>, inlet port <NUM>, outlet port <NUM>, pipes <NUM>, first cold inlet face <NUM>, second cold outlet face <NUM>, hot flow <NUM>, cold flow <NUM>, first region <NUM>, and second region <NUM>. Throughout this disclosure, the terms, elements, and/or components of "engine cooler" and "heat exchanger" can be used interchangeably.

Engine cooler <NUM> is an additively manufactured fractal heat exchanger core. In this example, engine cooler <NUM> is symmetric about a vertical plane (with vertical being in an upward direction in <FIG>) through a midpoint of engine cooler <NUM>. Also, in this example engine cooler <NUM> includes a slight arc or curve from inlet port <NUM> to outlet port <NUM>. In other embodiments, engine cooler <NUM> can include a non-arcuate shape such as a cuboid. In this example, engine cooler <NUM> include a symmetric design such that the hot and cold circuits are reversible.

Rotational axis <NUM> is an axis of rotation of engine cooler <NUM>. Inlet port <NUM> and outlet port <NUM> are fluidic ports for transferring a fluid (e.g., air). Pipes <NUM> are elongate tubes with fluidic passages extending therethrough. First cold inlet face <NUM> and second cold outlet face <NUM> are opposing side-faces of engine cooler <NUM>. Hot flow <NUM> is a flow of hot air such as bleed air from the aircraft engine. Cold flow <NUM> is a flow of cold air such as from RAM air. First region <NUM> and second region <NUM> are corners of engine cooler <NUM>. In another example, first region <NUM> and second region <NUM> can each extend a length of an edge of engine cooler <NUM>.

Rotational axis <NUM> passes through a mid-point of engine cooler <NUM>. In this example, rotational axis <NUM> passes vertically through engine cooler <NUM> due to engine cooler <NUM> being symmetric about a vertical plane. In an example where engine cooler <NUM> includes a cuboid configuration, rotational axis <NUM> or another rotational axis can also pass through the midpoint of engine cooler <NUM> and perpendicular to the up-down orientation of rotational axis <NUM> shown here in <FIG>.

Inlet port <NUM> is disposed on a first end of engine cooler <NUM> and is fluidly connected to pipes <NUM>. Outlet port <NUM> is disposed on an opposite end of engine cooler <NUM> from inlet port <NUM> and is fluidly connected to pipes <NUM>. Pipes <NUM> extend between and are fluidly connected to inlet port <NUM> and outlet port <NUM>. First face <NUM> is disposed on a first side of engine cooler <NUM>. Second face <NUM> is disposed on an opposite side of engine cooler <NUM> from first face <NUM>. Hot flow <NUM> passes through and inside of inlet port <NUM>, outlet port <NUM>, and pipes <NUM>. Cold flow <NUM> enters into engine cooler <NUM> across first face <NUM>, passes through gaps and spaces between individual pipes <NUM>, and exits out of engine cooler <NUM> through second face <NUM>. First region <NUM> is disposed on an end of pipes <NUM> adjacent to and immediately downstream from inlet port <NUM>. Second region <NUM> is disposed on an end of pipes <NUM> opposite from first region <NUM> and is adjacent to and immediately upstream from outlet port <NUM>.

Engine cooler <NUM> transfers thermal energy between hot flow <NUM> and cold flow <NUM>. Rotational axis <NUM> serves as an axis about which engine cooler <NUM> can be rotated about in order to reverse the relative directions of hot flow <NUM> and cold flow <NUM> through engine cooler <NUM>. In this example, inlet port <NUM> receives hot flow <NUM> and transfers hot flow <NUM> into pipes <NUM>. Whereas, in another example with engine cooler <NUM> being rotated <NUM>° about rotational axis <NUM>, inlet port <NUM> would become an outlet port as hot flow <NUM> would be passing from pipes <NUM> to inlet port <NUM> and out of engine cooler <NUM>.

In this example, outlet port <NUM> receives hot flow <NUM> from pipes <NUM> and transfers hot flow <NUM> out of engine cooler <NUM>. In this example, pipes <NUM> transport hot flow <NUM> from inlet port <NUM> to outlet port <NUM>. Also, due to pipes <NUM> being spaced from each other, the spaces between individual pipes <NUM> provide an area through which cold flow <NUM> flows. As cold flow <NUM> flows across exterior surfaces of pipes <NUM>, thermal energy is transferred from hot flow <NUM> passing through pipes <NUM>, across the physical material of pipes <NUM>, and into cold flow <NUM> passing across the surfaces of pipes <NUM>. In this way, engine cooler <NUM> transfers thermal energy from hot flow <NUM> to cold flow <NUM>. In this example, cold flow <NUM> enters into engine cooler <NUM> through first face <NUM>. Likewise, cold flow <NUM> exits engine cooler <NUM> through second face <NUM>. Hot flow <NUM> carries thermal energy into heat exchange core <NUM>. As hot flow <NUM> passes through pipes <NUM>, thermal energy is transferred from hot flow <NUM> to cold flow <NUM> across pipes <NUM>.

In this example, first region <NUM> represents a corner of engine cooler <NUM> that gets the hottest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, as hot flow <NUM> passes into pipes <NUM>, hot flow <NUM> contains the highest amount of thermal energy as hot flow <NUM> first enters into pipes <NUM>. Then, as hot flow <NUM> passes down pipes <NUM>, hot flow <NUM> is subjected to transfer of thermal energy as cold flow <NUM> passes across pipes <NUM>. Also, in this example, second region <NUM> represents a corner of engine cooler <NUM> that is the coldest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, as hot flow <NUM> passes into pipes <NUM>, hot flow <NUM> contains the lowest amount of thermal energy as hot flow <NUM> is about to exit pipes <NUM>. In addition, the location of second region <NUM> is right at first face <NUM> where cold flow <NUM> is entering into engine cooler <NUM> and where cold flow <NUM> is at its coldest (e.g., has the lowest amount of thermal energy).

Here, because engine cooler <NUM> is symmetrical, engine cooler <NUM> has the capability to rotate about rotational axis <NUM> thus making the outlet the inlet and the inlet the outlet for both the hot and the cold sides of engine cooler <NUM>. For example, rotating engine cooler <NUM> about rotational axis <NUM>, will make inlet port <NUM> into an outlet and outlet port <NUM> into an inlet as well as causing first face <NUM> to become an outlet side-face and second face <NUM> to become an inlet side-face of engine cooler <NUM>. After engine cooler <NUM> has been rotated <NUM>° about rotational axis <NUM>, engine cooler <NUM> is then reinstalled back into position.

In rotating engine cooler <NUM><NUM>° about rotational axis <NUM>, first region <NUM> that had been subjected to high amounts of thermal energy stress will be on the opposite corner where first region <NUM> is not going to be stressed further and second region <NUM> (the other low thermal energy stress corner) will be exposed to some of the thermal fatigue cycles because second region <NUM> will receive high temperature air from outlet port <NUM> (which will be an inlet port due to the <NUM>° rotation). (See e.g., <FIG> for further discussion of the rotation/reversal of engine cooler <NUM>).

<FIG> is a simplified schematic view of engine cooler <NUM> in a first installation orientation N and shows rotational axis <NUM>, inlet port <NUM>, outlet port <NUM>, first face <NUM>, second face <NUM>, hot flow <NUM>, cold flow <NUM>, first region <NUM>, and second region <NUM>. Pipes <NUM> are omitted here for clarity. <FIG> is a simplified schematic view of engine cooler <NUM>' in a second installation orientation N+<NUM> and shows rotational axis <NUM>, inlet port <NUM>, outlet port <NUM>, first face <NUM>, second face <NUM>, hot flow <NUM>, cold flow <NUM>, first region <NUM>, and second region <NUM>. <FIG> will be discussed in tandem.

In <FIG>, engine cooler <NUM> is shown as occupying installation orientation N which involves inlet port <NUM> receiving hot flow <NUM>, outlet port <NUM> porting out hot flow <NUM>, first face <NUM> receiving cold flow <NUM>, and second face <NUM> porting out cold flow <NUM>. In orientation N, first region <NUM> represents a corner of engine cooler <NUM> that gets the hottest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, hot flow <NUM> contains the highest amount of thermal energy as hot flow <NUM> first enters into engine cooler <NUM> through inlet port <NUM>. Then, as hot flow <NUM> passes down engine cooler <NUM>, hot flow <NUM> is subjected to transfer of thermal energy as cold flow <NUM> passes across engine cooler <NUM>. Likewise, second region <NUM> represents a corner of engine cooler <NUM> that is the coldest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, as hot flow <NUM> passes through engine cooler <NUM>, hot flow <NUM> contains the lowest amount of thermal energy as hot flow <NUM> is about to exit engine cooler <NUM>. In addition, the location of second region <NUM> is right at first face <NUM> where cold flow <NUM> is entering into engine cooler <NUM> and where cold flow <NUM> is at its coldest (has the lowest amount of thermal energy).

In <FIG>, engine cooler <NUM>' is shown as occupying installation orientation N+<NUM>. In orientation N+<NUM>, engine cooler <NUM>' has been rotated <NUM>° from orientation N about rotational axis <NUM>. Due to this <NUM>° rotation, engine cooler <NUM>' is oriented such that outlet port <NUM> receives hot flow <NUM>, inlet port <NUM> ports out hot flow <NUM>, second face <NUM> receives cold flow <NUM>, and first face <NUM> ports out cold flow <NUM>. In this orientation N+<NUM>, second region <NUM> represents a corner of engine cooler <NUM>' that gets the hottest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, hot flow <NUM> contains the highest amount of thermal energy as hot flow <NUM> first enters into engine cooler <NUM>' through outlet port <NUM>. Then, as hot flow <NUM> passes down engine cooler <NUM>', hot flow <NUM> is subjected to transfer of thermal energy as cold flow <NUM> passes across engine cooler <NUM>'. Likewise, first region <NUM> represents a corner of engine cooler <NUM>' that is the coldest due to its positioning relative to hot flow <NUM> and cold flow <NUM>. For example, as hot flow <NUM> passes through engine cooler <NUM>', hot flow <NUM> contains the lowest amount of thermal energy as hot flow <NUM> is about to exit engine cooler <NUM>' through inlet port <NUM>. In addition, the location of first region <NUM> is right at second face <NUM> where cold flow <NUM> is entering into engine cooler <NUM>' and where cold flow <NUM> is at its coldest (has the lowest amount of thermal energy).

In rotating engine cooler <NUM> between orientation N and orientation N+<NUM>, the higher amount of thermal fatigue subjected to the corner of engine cooler <NUM> positioned nearest the inlet of hot flow <NUM> and nearest the outflow of cold flow <NUM> (e.g., first region <NUM> in engine cooler <NUM> and second region <NUM> in engine cooler <NUM>') is not always applied to the same spot. A certain amount of thermal fatigue or wear is applied to first region <NUM> while engine cooler <NUM> occupies orientation N for so many operation cycles, and then gets rotated into orientation N+<NUM> so that second region <NUM> can be subjected to higher amounts of thermal fatigue. In this way, the thermal fatigue to due high temperatures gradients can be distributed across both first region <NUM> and second region <NUM> resulting in distribution of any correlated damage and an increase in the life expectancy of engine cooler <NUM>.

<FIG> is a flowchart of communicating maintenance data and shows AMD <NUM>, PHM data <NUM>, optical scanner <NUM>, and placard <NUM>.

AMD <NUM> is an aircraft maintenance database. PHM data <NUM> is prognostic health management ("PHM") data. In this example, PHM data <NUM> includes a cycle count or a number of duty cycles of the aircraft, the aircraft engine, and/or of engine cooler <NUM>. PHM data <NUM> can also include a number of service hours, aircraft identification, and an orientation/position of engine cooler <NUM>. Optical scanner <NUM> is a device for optically scanning an item. In this example, optical scanner <NUM> includes a camera as part of a handheld unit such as a cellular telephone. In another example, optical scanner <NUM> can be a device configured to optically scan a RFID tag such as an RFID scanner or a smartphone (e.g., running an iOS or Android OS). In other examples, optical scanner <NUM> can be a device configured to read data via one or more forms of automatic identification and data capture. Placard <NUM> is a label or a signage plate. In this example, placard <NUM> includes a dot matrix label. In another example, placard <NUM> can include a label or an engravement.

In this example, AMD <NUM> is an electronic database disposed separately from the aircraft. In this example, PHM data <NUM> can be produced by and/or tracked by the aircraft. In this example, optical scanner <NUM> is connected via a wired or wireless connection to AMD <NUM>. Placard <NUM> is mounted onto one of ECS packs 14A or 14B, first or second heat exchanger 20A or 20B, or engine cooler <NUM>.

In this example, AMD <NUM> stores and tracks a maintenance schedule for the aircraft. PHM data <NUM> is used to track relevant data of the aircraft and is used by AMD <NUM> to determine and suggest appropriate maintenance events. Optical scanner <NUM> functions by optically scanning information stored on engine cooler <NUM> and communicating that information to AMD <NUM>. For example, optical scanner <NUM> scans placard <NUM> in response to an action by the mechanic. Placard <NUM> contains and stores information to be scanned by optical scanner <NUM> and to visually indicate information to a mechanic.

In one example, a method of communicating maintenance data includes marking engine cooler <NUM>. Here, engine cooler <NUM> can be marked with at least one of a placard, a dot matrix label, an RFID tag, and an engravement. The marking on engine cooler <NUM> is scanned with an optical sensor. Here, the marking can be stored on placard <NUM>. A first orientation N of engine cooler <NUM> is detected based on the scanned part marking. The detected orientation of the engine cooler is reported to AMD <NUM>. For example, a mechanic can enter the orientation of engine cooler <NUM> into AMD <NUM> as engine cooler <NUM> goes on to or comes off the aircraft to aid in determining the next position/orientation of engine cooler <NUM>. A recommendation of installation position is provided by AMD <NUM> based on the detected orientation of engine cooler <NUM> and on PHM data <NUM> of the aircraft. In this example, the recommendation of installation is based on a tracked number of duty cycles, which is tracked by AMD <NUM>. Engine cooler <NUM> is then installed into position onto the aircraft based on the recommended installation position from AMD <NUM>.

In this example, providing the recommendation of installation position includes instructing a mechanic with AMD <NUM> to install engine cooler <NUM> in one of either the first orientation N or a second orientation N+<NUM>, which is rotated <NUM>° from first orientation N. Here, the instruction is based on updated maintenance records and on information in AMD <NUM>.

In another example, a method of tracking an engine cooler in an aircraft includes recording an orientation of engine cooler <NUM> as orientation N. Here, recording the orientation of engine cooler <NUM> can include recording the orientation of engine cooler <NUM> in AMD <NUM>. PHM data <NUM> of the aircraft is tracked. In this example, PHM data <NUM> can include a cycle count, a number of duty cycles, and/or a number of operation hours of the aircraft. A maintenance check of the aircraft is performed based on the tracked PHM data <NUM>. A determination is made with AMD <NUM> as to whether to rotate an orientation of engine cooler <NUM> based on the tracked PHM data <NUM> of the aircraft. A recommendation is provided by AMD <NUM> as to whether to rotate engine cooler <NUM>. Engine cooler <NUM> is either rotated or not rotated based on the recommendation of AMD <NUM> as to whether to rotate engine cooler <NUM>. Here, rotating engine cooler <NUM> can include rotating engine cooler <NUM><NUM>° about a centerline axis (e.g., rotational axis <NUM>) of engine cooler <NUM>. The orientation of engine cooler <NUM> is then recorded as orientation N+<NUM>.

In one example, there can be a visible reference mark on engine cooler <NUM> that indicates to the mechanic which way to orient engine cooler <NUM> relative to its previous position. For example, a physical or inked demarcation can be placed adjacent to inlet <NUM>. Then, looking towards the engine outlet, the demarcation might be to the right for orientation N. At the next rotation (i.e., orientation N+<NUM>), the demarcation would be on the left side (looking towards the engine outlet). Instructions could then be communicated via optical scanner <NUM> or by other instructions. In another example, a gyroscope sensor can be used to sense the orientation of engine cooler <NUM> and indicate to the mechanic which way to orient engine cooler <NUM> relative to its previous position. The gyroscope sensor can be a part of or separate from optical scanner <NUM>. For example, the gyroscope sensor (e.g., of optical scanner <NUM>) can be placed in alignment with a placard (e.g., a QR code placard) on engine cooler <NUM>. With the gyroscope sensor in place on engine cooler <NUM>, the orientation of engine cooler can be determined based on the sensed orientation of the gyroscope sensor. Instructions could then be communicated via optical scanner <NUM> or by other instructions whether the orientation of engine cooler <NUM> needed to be switched or to remain as-is.

<FIG> is a flowchart of method <NUM> of managing a maintenance schedule of engine cooler <NUM>. Method <NUM> includes steps <NUM>-<NUM>.

Step <NUM> includes installing engine cooler <NUM> on to an engine. Step <NUM> includes marking the orientation of engine cooler <NUM> and a date of service onto placard <NUM> of engine cooler <NUM>. In another embodiment, step <NUM> can be replaced with scanning the placard and uploading the information to AMD <NUM>. Step <NUM> could include scanning a data matrix on engine cooler <NUM>. Then, the information from scanning the data matrix can be digitally reported to or entered directly into AMD <NUM>. Step <NUM> includes recording an orientation N in AMD <NUM> that identifies a position of engine cooler <NUM>. Step <NUM> includes operating the aircraft. Step <NUM> includes tracking a cycle count of the aircraft. In one example, a cycle count of the aircraft can be or be based on a number of service hours of the engine cooler, the engine, and/or of the aircraft.

Step <NUM> includes determining if the tracked cycle count meets a first threshold value. Here, the threshold value can be a predetermined amount of cycle counts or service hours of the engine cooler, the engine, and/or of the aircraft. If the tracked cycle count does not meet the first threshold value, then the aircraft is returned to operation as shown in step <NUM>. If the tracked cycle count does meet the first threshold value, then the method proceeds to step <NUM>.

Step <NUM> includes performing a maintenance check of the aircraft. In one example, the maintenance check can be a regularly scheduled A-check, B-check, or a C-check of the aircraft. Step <NUM> includes removing engine cooler <NUM> from the aircraft. Step <NUM> also includes steps <NUM> through <NUM>. Step <NUM> includes inspecting engine cooler <NUM> during the maintenance check. Step <NUM> includes determining a need for repairing or cleaning engine cooler <NUM> based on the inspection of engine cooler <NUM>. For example, if engine cooler <NUM> shows signs of a crack, a deposit of dirt, or a sign of localized thermal fatigue, then engine cooler <NUM> can be cleaned and/or repaired as necessary to address these issues. If there is a need for repairing or cleaning engine cooler <NUM> based on the inspection, then the cleaning or repairing is completed as step <NUM>. After step <NUM> is completed, then the method proceeds to step <NUM>. If there is not a need for repairing or cleaning engine cooler <NUM> based on the inspection, then the method proceeds to step <NUM>, bypassing step <NUM>.

Step <NUM> includes determining whether engine cooler <NUM> needs to be rotated. Here, determining whether to rotate engine cooler <NUM> is based on whether engine cooler <NUM> has met a second threshold amount of cycle counts or service hours since engine cooler <NUM> was last rotated. In another example, determining whether to rotate engine cooler <NUM> can be based on whether engine cooler <NUM> shows signs of thermal fatigue. If engine cooler <NUM> meets the threshold value of cycle counts or service hours, then the method proceeds to step <NUM>. Here, a number of cycle counts and service hours is stored and tracked in AMD <NUM>. Additionally, the previous orientation of engine cooler <NUM> is stored in AMD <NUM>, so that AMD <NUM> can instruct the user (e.g., mechanic) as to which position/orientation engine cooler <NUM> was removed from and which position/orientation engine cooler <NUM> should be replaced into. If engine cooler <NUM> does not meet the threshold value of cycle counts or service hours, then the method proceeds to step <NUM>.

Step <NUM> includes reversing an orientation of engine cooler <NUM>. In this example, reversing the orientation of engine cooler <NUM> can include rotating engine cooler <NUM><NUM>° about a first centerline axis (e.g., rotational axis <NUM>) of engine cooler <NUM>. Step <NUM> includes marking orientation N+<NUM> and a corresponding date of service onto placard <NUM> of engine cooler <NUM>. In another embodiment, step <NUM> can be optional if the placard is scanned and the scanned information uploaded to AMD <NUM>. In such an embodiment, AMD <NUM> could then advise what the next recommended position of engine cooler <NUM> should be using optical scanner <NUM> (e.g., smartphone). Step <NUM> includes updating AMD <NUM> to indicate the reversed orientation of engine cooler <NUM> as orientation N+<NUM>. Step <NUM> includes scanning the updated AMD <NUM> with optical scanner <NUM> to determine a value of the orientation. Step <NUM> includes replacing engine cooler <NUM> into the aircraft. Step <NUM> includes returning the aircraft to regular operation.

A method of tracking an engine cooler in an aircraft includes recording an orientation of the engine cooler as orientation N. Prognostic health management data of the aircraft is tracked. A maintenance check of the aircraft is performed based on the tracked prognostic health management data. Whether to rotate an orientation of the engine cooler is determined with an aircraft maintenance database based on the tracked prognostic health management data of the aircraft. A recommendation is provided by the aircraft maintenance database as to whether to rotate the engine cooler. The orientation of the engine cooler is recorded as orientation N+<NUM>.

The method of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following steps, features, configurations and/or additional components.

The orientation of the engine cooler can be recorded in the aircraft maintenance database.

The prognostic health management data can comprise a cycle count of the aircraft.

The engine cooler can be rotated by a user based on the recommendation of the aircraft maintenance database as to whether to rotate the engine cooler.

The engine cooler <NUM>° can be rotated about a first centerline axis of the engine cooler.

A method of managing an orientation of an engine cooler includes marking the engine cooler. The marking on the engine cooler is scanned with a scanner. A first orientation N of the engine cooler is detected based on the scanned marking. The detected orientation of the engine cooler is reported to the aircraft maintenance database. Maintenance records, of the aircraft maintenance database, are updated with the reported detected orientation of the engine cooler. A recommendation of installation position is provided based on the detected orientation of the engine cooler and on prognostic health management data of the aircraft. The engine cooler is installed onto the aircraft based on the recommended installation position from the aircraft maintenance database.

The recommendation of installation can be based on a tracked number of duty cycles, an amount of which is tracked by the aircraft maintenance database.

A user can be instructed with the aircraft maintenance database to install the engine cooler in one of either the first orientation N or a second orientation N+<NUM>, wherein the second N+<NUM> orientation can be rotated <NUM>° from first orientation N, wherein the instruction can be based on updated maintenance records and/or on information in the aircraft maintenance database.

The engine cooler can be marked with at least one of a placard, a dot matrix label, a radio-frequency identification tag, and an engravement.

The marking can be scanned with an optical sensor or a radio-frequency identification reader.

A method of managing maintenance of an environmental control system of an aircraft includes installing a first heat exchanger as part of the environmental control system. An orientation N identifying a position of the first heat exchanger is recorded in an aircraft maintenance database. A cycle count of the aircraft is tracked with a cycle counter. A maintenance check of the aircraft is performed when the tracked cycle count reaches a threshold value. The first heat exchanger is removed from the aircraft. Whether to rotate an orientation of the heat exchanger is determined based on the tracked cycle count of the aircraft. An orientation of the heat exchanger is reversed. The aircraft maintenance database is updated to indicate the reversed orientation of the first heat exchanger as orientation N+<NUM>. The first heat exchanger is replaced into the aircraft.

The first heat exchanger can be inspected during the maintenance check, the need for cleaning or repairing the first exchanger can be identified based on the inspection of the first heat exchanger, and/or at least one of cleaning and repairing of the first heat exchanger can be performed.

The first engine cooler can be inspected for a crack, a deposit of dirt, or a sign of localized thermal fatigue.

The updated aircraft maintenance database can be scanned to determine a value of the orientation.

The orientation of the first heat exchanger and a date of service can be marked onto a placard of the first heat exchanger.

An orientation N+<NUM> and/or a corresponding date of service can be marked onto a placard of the first heat exchanger.

Claim 1:
A method of tracking an orientation of an engine cooler in an aircraft, the method comprising:
recording, in an aircraft maintenance database (<NUM>), the orientation of the engine cooler (<NUM>) as orientation N;
tracking prognostic health management data (<NUM>) of the aircraft;
performing a maintenance check of the aircraft based on the tracked prognostic health management data;
determining, with the aircraft maintenance database (<NUM>), whether to rotate an orientation of the engine cooler (<NUM>) based on the tracked prognostic health management data (<NUM>) of the aircraft;
providing, with the aircraft maintenance database (<NUM>), a recommendation as to whether to rotate the engine cooler (<NUM>);
rotating, by a user, the engine cooler (<NUM>) based on the recommendation of the aircraft maintenance database (<NUM>) as to whether to rotate the engine cooler (<NUM>); and
recording the orientation of the engine cooler (<NUM>) as orientation N+<NUM>.