Subprocedures.

Next: Follow on maintenance. Up: High level structure Previous: Input conditions.

Subprocedures.

The three subprocedures (removal - installation - checkout) are organized as sequences of sequentially numbered steps. Each step may be indexed by the alphabetical identifier of the technician that has to perform it. E.g. Step 1 of subprocedure Removal of Fuel Flow Proportioner has to be performed by technician B:

1. (B) Depressurize hydraulic systems A and B. (General Maintenance)

Interspersed through the steps, and preceding the step(s) they refer to, are WARNINGs, CAUTIONs, and NOTEs. WARNINGs and CAUTIONs are used as described above, while NOTEs are used as follows:

To identify under which conditions certain steps have to be executed, e.g.
NOTE
Omit steps 28 through 31 if original FFP [Fuel Flow Proportioner] is to be reinstalled.
To specify constraints.
- Constraints may be global to the whole subprocedure --- in this case the NOTE appears at the beginning of the subprocedure, before the sequence of steps starts:
  NOTE
  All serviceable parts will be retained for reinstallation.
- Constraints may apply only to a subsequence of steps:
  NOTE
  Petrolatum shall be used for lubricant when required in following steps.
  The subsequence may be composed of a single step: the following NOTE provides a constraint on the execution of the action install, described in step 3 (recall that (A) in step 3 refers to technician (A)):
  NOTE
  Screw shall be installed in lower outboard corner of pump and support.
  3.
  (A) Position support on pump and install three bolts and screw. Torque three bolts and screw to 40-60 inch-pounds.
Finally, a NOTE may describe actions that shouldn't or couldn't be performed in connection with the step following the NOTE, 7 in this case:
NOTE
Upper outboard bolt cannot be removed at this time due to interference by lower engine supply fuel tube and supply elbow.
7.
(A) Remove three bolts (two inboard and lower outboard), three washers, and three sealing washers. Discard three sealing washers.

The last component appearing in subprocedures is RESULT. RESULT refers to the immediately preceding step

, and describes a condition that

either brings about (as for step 19 below) or is used to verify (as for step 20 below) --- step 19 and 20 are part of the same subprocedure (checkout of fuel/oil heat exchanger):

19.
(B, C) Increase hydraulic system A pressure to 3000 psig as indicated on HYD PRESS A indicator.
RESULT:
Ground test panel FFP advisory light comes on. (28-23-DF)
20.
(A) Inspect all disturbed connections for leakage.
RESULT:
No leakage allowed. (28-23-FD)

If a RESULT concerns more than one condition, there will be a list of such conditions under a single heading RESULT. Presumably the reference codes in parentheses refer to what should be done in case the expected condition doesn't hold.

Note that the structure of the procedures described in the first section of the manual is the same as that just described: namely, they include WARNINGs, CAUTIONs, NOTEs and RESULTs, but they don't include Input conditions and Follow-up maintenance.

Next: Follow on maintenance. Up: High level structure Previous: Input conditions.

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