Oil consumption monitoring

The oil consumption rate is the amount of oil uptake per unit of operating hour. Maintenix can calculate the oil consumption rate for inventory, and assign an oil consumption status value to the inventory. Maintenance control personnel can use this status to detect inventory that is exceeding normal oil consumption, and then plan maintenance activities accordingly.

Maintenix calculates the oil consumption rate exclusively for assemblies that have the assembly class of engine (ENG) or auxiliary power unit (APU). The oil consumption calculation is based on a measurement parameter and a usage parameter. In the following example, the measurement parameter is the engine oil uptake in quarts, and the usage parameter is the engine operating hours.

Oil consumption rate = oil uptake / operating hours since last oil uptake.

Using the oil consumption rate and the threshold values you set for an assembly, Maintenix assigns an oil consumption status to each inventory item matching the assembly. The oil consumption status value of normal is predefined in Maintenix. Your organization can define additional oil consumption status values, such as caution and warning, by adding them to the Maintenix database. Authorized users then set the threshold values—the oil consumption rate value at which Maintenix must change the oil consumption status of the inventory.

For example, if you consider the oil consumption rate of one quart per hour as normal, you can define statuses of caution and warning for oil consumption rates exceeding two quarts per hour and three quarts per hour, respectively.

In addition to threshold values set on the assembly itself, you can set alternative threshold values— exceptions to the threshold values set on the assembly—for specific part numbers, operators, and serial numbers. The different threshold values created for an assembly override each other in the following order:

1. Assembly thresholds apply to all inventory defined under the assembly.

2. Part number specific thresholds—if defined—override the assembly thresholds for the specified part number.

3. Operator specific thresholds—if defined—override the assembly thresholds and the part number specific thresholds (if they exist) for the inventory owned by the specified operator.

4. Serial number specific thresholds—if defined—override all other thresholds for the specified serial number.

As an inventory item accrues usage and its oil uptake measurements are recorded, Maintenix calculates the oil consumption rate, and updates the oil consumption status as required. Maintenix can also send alerts to notify users about the status change.

Maintenix provides the High Oil Consumption To Do List tab, which lists the inventory items whose oil consumption status is not normal. You can filter the list to show only the high oil consumption inventory of a specific assembly, assembly class (ENG, APU, or both), part number, operator, oil consumption status, or any combination thereof.

Authorized users can manually escalate the oil consumption status of an inventory item, to add it to the watch list shown on the High Oil Consumption To Do List tab. Status escalation does not have to follow the sequence of status values. For example, the status of an item can go directly from normal to warning. When manual escalation is used, the automatic status update feature of Maintenix cannot downgrade the status for that inventory. However, it can further escalate the status, should a new oil consumption measurement warrant it. When it is deemed appropriate, for example after taking action to correct the situation, authorized users can reset the automatic status update feature on that inventory record, which makes it possible for Maintenix to downgrade the status.

You integrate oil consumption monitoring into your maintenance programs as follows:

1. Verify that your Maintenix administrator has completed the data setup explained in the "Oil consumption logging" section of the Maintenix Administration Guide.

2. Create the measurement parameter to use to measure the oil uptake. This measurement parameter must be defined as an assembly measurement for either the ENG or APU assembly class.

3. For each assembly to be monitored for oil consumption, such as engines and APUs, do the following:

   • Assign the usage parameter you want to use in the oil consumption calculation to a usage definition on the assembly. The usage parameter must be one that represents operating time, for example flying hours.

   • Create the oil consumption rate definition for the assemblies. This consists of the following:

     • Selecting the measurement parameter to use to measure oil uptake, and the operating time-based usage parameter.

     • Specifying the threshold values for the assembly.

     • Optionally, specifying part number specific, operator specific, and serial number specific threshold values.

4. Create task definitions on the aircraft itself to represent the work technicians will perform and for which they will record the oil uptake value. These can be requirement definitions with a job card to record the measurement, or executable requirements.

5. Assign the assembly measurements to be used for oil consumption tracking to the task definitions you have defined.

The current oil consumption status of an inventory is displayed on the Inventory Details page, Details tab. The oil consumption status transitions are displayed on the Inventory Details page, Historical > Oil Status tab.