Frequently Asked Questions Visit our Home Page

Q: How does one determine repair task times?

A: Have typical repairmen perform the indicated tasks while another records the task times using a stopwatch. Typically, repairmen experienced in repairing the equipment can pull these times from their memory. If feasible, refer to MIL-HDBK-472 Procedure V for default task times, as a guide.

Q: Why do you need to have a Reliability MTBF Prediction in order to perform an Maintainability MTTR Prediction?

A: MTTR Prediction is a function of both sub-assembly failure rate and repair times. See MTTR mathematical models in the examples section of our web page.

Q: What are definitions of the Corrective Maintenance Task Times?

A:	Localization:	Time associated with those tasks required to be performed before fault isolation can be executed.
	Fault Isolation:	Time associated with those tasks required to isolate the fault to the level at which fault correction begins.
	Disassembly:	Time associated with gaining access to the replaceable item or items identified during the fault isolation process.
	Interchange:	Time associated with the removal and replacement of a faulty replaceable item or suspected faulty item.
	Reassembly:	Time associated with closing up the equipment after interchange is performed.
	Alignment:	Time associated with aligning the system or replaceable item after a fault has been corrected.
	Checkout:	Time associated with the verification that a fault has been corrected and the system is operational.