Mission profile duration

3 posts / 0 new
Last post
YO
Mission profile duration

Hello Lambda!

I need your help about the mission profile setup of my equipment.Its mission profile duration is superior to 1 year.

I would like to know if I can define a yearly mission profile based on my non yearly mission profile, i.e. translate all the phases of the non yearly mission profile into phases of a yearly mission profile (with the same proportion).

If this way is not possible, what do I have to do? Will I have to change all the formulas of the models?

Thank you in advance.

Y.O.

Lambda
Re: Mission profile duration

Hello,

As explained page 25 of the FIDES Guide 2009, you can use life profiles longer or shorter than one year. It is for example usual for products with a very sequential life to use a life profile that describe the whole product life (for example 10 years).

And indeed, another way is to translate your mission profile to a yearly basis. This is not very complex (be careful with thermal cycles).

All models in the FIDES guide are presented with a duration of one year (8760 hours) because this is recommended in most case, and this is a step toward some standadisation in ways and customs. But the most important point is to use at the end failure rates by "calendar hour" and not "mission hour" or "functionning hour".

If you use a tool for your calculation, you should perhaps verify that the tool takes into account the real duration of the life profile and does not assume that it is 8760 hours. You can use any life profile duration with the FIDES Mill spreadsheet tool (FIDES Guide 2004A only).

In any case, if it is not done yet, I encourage you to read in details the life profile chapter of the FIDES Guide 2009 before creating your own mission profile. A lot of advices and explanations about the meaning of models have been put there.

All the best with FIDES!

Lambda

YO
Re: Mission profile duration

Dear Lambda!

Thank you for your comprehensive answer!

Best regards.