Task applicability

By default, each task definition applies to all of the possible inventory items that can fill the configuration slot specified in the task definition, or that match the part number of a task definition that is based on a part number. In reality however, not all task definitions apply to all possible inventory and not all steps in a job card apply to the same inventory. Maintenix lets you specify the inventory to which task definitions and steps within task definitions apply.

There are two ways to assign task applicability in Maintenix: the applicability range and the applicability rule.

Applicability range

The applicability range is specified in the task definition, and it consists of one or more applicability codes separated by commas; you use a hyphen to include several sequential codes in the applicability range. You can assign an applicability code to any piece of inventory with an inventory class of aircraft or assembly. The task definition only applies to inventory that has an applicability code that is within the applicability range of the task definition.

For task definitions defined on a system or tracked configuration slot that have an applicability range, Maintenix looks at the applicability code of the root inventory—the aircraft or the sub-assembly inventory.

Using an applicability range lets you set the applicability regardless of the various individual identifiers that may be used in a mixed fleet; for example, one aircraft manufacturer may define applicability using the part number, whereas another manufacturer uses the fin number. For engines, an internal tracking number may be used. By using applicability codes, all of the applicability ranges can be specified without having to determine which field to use.

If a task definition (executable requirement or job card) includes job steps, you can also set the applicability range for each step. Different steps in one task definition can have different applicability ranges.

The following table provides some examples of applicability ranges.

Applicability range examples
Applicability Range Result
332, A12 Includes only 332 and A12.
332, 348-350

Includes 332, 348, 349, 350.

Also includes any 3-character string that is within the range, such as 34A, 34Z.

Does not include 35A.

A100-A199

Includes: A100, A101, ...., A199.

Also includes any 4-character string that is with the range, such as A10A, A18Z.

Does not include A, A1, A10, A19A.

  If the applicability range is blank (not specified), it includes all inventory.
N/A Does not include any inventory.
Note:

If an inventory item does not have an applicability code—the field is left blank in the inventory record—all task definitions defined on the corresponding assembly apply to the inventory, regardless of the applicability range set in the task definitions.

Applicability rule

Another way to assign task applicability is to define an applicability rule. (You can use applicability rules with task definitions, but to specify applicability for job steps, you can only use applicability ranges.)

To define the applicability rule when you create the assembly or component in Maintenix, you can use any of the following identifiers:

Identifiers used in applicability rules
Common Name Identifier to be Used
Aircraft Part Number [Aircraft Part No]
Aircraft Serial Number [Aircraft Serial No]
Aircraft Fin Number [Aircraft Fin No]
Aircraft Var Number [Aircraft Var No]
Aircraft Line Number [Aircraft Line No]
Aircraft Operator [Aircraft Operator]
Assembly Part Number [Assembly Part No]
Assembly Serial Number [Assembly Serial No]
Assembly Operator [Assembly Operator]
Assembly Owner Name [Assembly Owner Name]
Assembly Owner Code [Assembly Owner Code]
Component Part Number [Component Part No]
Component Serial Number [Component Serial No]
Component Lot Number [Component Lot No]
Component Manufacturer [Component Manufacturer]
Component Owner Name [Component Owner Name]
Component Owner Code [Component Owner Code]

A basic applicability rule can be created using the following format:

[Aircraft Part No] = 'B767-232'

This applicability rule states that this task definition applies to all inventory that has an aircraft part number of B767-232.

Note:

The part number must be in quotes for Maintenix to treat it as a character string.

More complex applicability rules can be created using the operators in the following table.

Applicability Rule Operators
Operator Description
= The value before the operator is equal to the value after the operator. The two operands must have the same number of characters.
and Both the expression before and the expression after the 'and' must be met.
or Either the expression before or the expression after the 'or' must be met.
and not The expression after the 'and not' is excluded.
( ) The open and close bracket are used to group information together. Any operations within the brackets are performed first.
< The value before the operator is less than the value after the operator.
<= The value before the operator is less than or equal to the value after the operator.
> The value before the operator is greater than the value after the operator.
>= The value before the operator is greater than or equal to the value after the operator.
BETWEEN This operator is used to select a range of data between two values. This operator can be used for strings, integers, and dates:

BETWEEN 'string1' AND 'string2'

BETWEEN integer1 AND integer2

BETWEEN date1 AND date2

The result includes the boundary values such as 'string1', 'string2', integer1, and integer2.

IN The value before the operator matches one of the values specified after the operator (in brackets, and separated by commas).
LIKE The character string before the operator matches the character string after the operator (which contains wildcard characters "%" and/or "_"). "%" can be any number of characters. "_" can be any single character.
Note: Wildcard characters cannot be used on the Unconstrained Task Definition and Unconstrained Task search pages.
NOT Negates the logical value of the expression that it precedes. For example:

NOT('123'='123') is FALSE

TO_CHAR The TO_CHAR operator converts a column's content to a string. The syntax is as follows:

TO_CHAR(number)
TO_NUMBER The TO_NUMBER operator converts a string to a number. The syntax is as follows:

TO_NUMBER('string')
SUBSTR The SUBSTR functions allows you to extract a substring from a string. The syntax is as follows:

SUBSTR( string, start_position, [ length ] )

This operator can be used with the TO_NUMBER operator to use a section of a string, and then convert it to a number. For example:

TO_NUMBER(SUBSTR([Component Serial No],-6,6)) >= 055555

If the start_position is negative, count the number of characters starting from the end of the string. For example, SUBSTR('Maintenix',-3,3) is 'nix', the last 3 characters of 'Maintenix'.

The applicability rule validation logic in Maintenix verifies column names and functions, but not the syntax, nor does it guarantee correct results.

Maintenix stores the identifiers used in applicability rules as character strings. While defining your applicability rules, you must consider character string comparison conventions and rules, such as the following:

  • Any constant used in the rules must be in quotes because Maintenix treats them as character strings, not numeric values.

    [Aircraft Part No] = '100' is a valid rule

    [Aircraft Part No] = 100 is not a valid rule

  • The operands on both sides of the equality operator, =, must have the same length. Otherwise, the comparison result is FALSE, implying that the two operands are not equal.
  • The operands for the less than ,< , and the greater than ,> , operators do not have to have the same length. Characters in strings are compared one by one, starting from the left, until an inequality is found.

    '9' < '10' is FALSE, because the ASCII code for 9 (57) is greater than the ASCII code for 1 (49)

    '09' < '10' is TRUE

Examples:

  1. [Aircraft Part No] = '123' and [Component Serial No] > '456 ' and not [Component Manufacturer] = 'ABC Inc.'

    This expression is TRUE when all of the following statements are true:

    • The aircraft part number is 123.
    • The lot number is greater than 456.
    • The manufacturer is not ABC Inc.
  2. ( [Component Part No] < '200' and [Component Manufacturer] = 'ABC Inc.' ) or ( [Component Part No] > '400' and [Component Manufacturer] = 'XYZ Inc.' )

    Applies to the following inventory:

    • Part numbers smaller than 200, manufactured by ABC Inc.

      If the component part number is '100', [Component Part No] < '200' is TRUE.

      If the component part number is '0100', [Component Part No] < '200' is FALSE, because the two operands of the character comparison are not of the same length.

      If the component part number is '300', [Component Part No] < '200' is FALSE.

  3. Part numbers bigger than 400, manufactured by XYZ Inc.

    If the component part number is '500', [Component Part No] > '400' is TRUE.

    If the component part number is '0500', [Component Part No] > '400' is FALSE, because the two operands of the character comparison are not of the same length.

    If the component part number is '300', [Component Part No] > '400' is FALSE.

  4. [Aircraft Fin No] IN ( '200','210','220')

    The fin number must be one of 200, 210, or 220.

    This rule is equivalent to ( [Aircraft Fin No] = '200' ) or ( [Aircraft Fin No] = '210' ) or ( [Aircraft Fin No] = '220' )

  5. [Aircraft Fin No] NOT IN ( '200','210','220')

    The fin number can be anything other than 200,210, or 220.

  6. SUBSTR ([Assembly Owner Name], 1, 2 ) BETWEEN 'AA' AND 'AC'

    The assembly owner name must start with 'AA' , 'AB' , or 'AC' .

  7. TO_NUMBER ([Component Part No]) BETWEEN 100 AND 120

    The component part number is between 100 and 120 (includes 100 and 120).

  8. SUBSTR ( TO_CHAR ([Component Part No]), -1, 1) = '0'

    The component part number ends with a zero.

  9. [Component Manufacturer] LIKE 'A%'

    Any manufacturer name that starts with "A".

  10. [Component Lot No] LIKE 'A_'

    Any two-character lot number that starts with "A".

Aircraft Applicability

A task definition that applies to certain aircraft, regardless of what component is on the aircraft, should have the applicability rule set to the aircraft on which the component is installed. Be aware that if this component is removed for another reason, the task is still applicable to the aircraft regardless of what inventory is installed in its place.

For aircraft applicability use Applicability, Aircraft Part Number, Aircraft Serial Number, Aircraft Fin Number, Aircraft Var Number, and Aircraft Line Number.

  • Aircraft Fin Number is a number given by an airline to each of the aircraft in their fleet.
  • Aircraft Var Number is a number assigned to an aircraft during manufacturing. It is often referenced in documentation sent to the airlines, such as service bulletins (SBs).
  • Aircraft Line Number is also a number assigned (by the OEM) to an aircraft during manufacturing. It represents the sequence number of the aircraft coming out of the assembly line for that aircraft type, for example, the 1275th aircraft of a particular aircraft type. It is often referenced in documentation sent to the airlines, such as SBs.

Component Applicability

A task definition that applies to specific component inventory, regardless of what aircraft or assembly it is installed on, should have the applicability rule set for the component itself. You can specify which inventory items apply by Component Part Number, Component Serial Number, Component Lot Number, Component Manufacturer, or Component Owner.