Talk:Mean down time

Latest comment: 12 years ago by 96.244.247.130 in topic Down vs. Degraded - How is failure determined?

I believe that MTTR (Mean Time To Repair) does include any and all time regardless of the reason including troubleshooting time, and the time spent otherwise waiting for a component to be brought back to a working state. This is contrary to the statement made in the article. --24.183.216.14 04:47, 26 December 2006 (UTC)Reply

Hmmmm, thanks for your comment. If this is the case, what is the difference between MDT and MTTR? Also, the R in MTTR can stand for many words, it's not well defined (see MTTR article). If you have a source for saying MTTR includes all down time involved, please, make the appropriate edit. Flippin42

Believe I answered both of these MTR issues by adding components and previous edits to MTTR; I've been short on references so far though. Garykempen (talk) 16:43, 16 September 2009 (UTC)Reply

From Jones, Logistics Support Analysis Handbook (TAB Books inc.), the time clock for MTTR starts and ends only with the corrective maintenance cycle (fault detection, isolation through checkout). MDT accounts for all including delays where spares, support personnel or tools are not immediately available. MTTR is used in calculating Ai (Inherent Availability) where MDT is used in calculating Ao (Operational Availability).

Down vs. Degraded - How is failure determined? edit

Can anyone make a clear distinction between downtime and degradation? For example, loss of hydraulic brake on a car is not a 100% failure - one can still downshift and/or use the parking brake. Is the car "down" or merely degraded? How can this be measured? How does one define failure? --96.244.247.130 (talk) 01:23, 4 July 2011 (UTC)Reply