Longest Path

Amir,

When a programme has actual dates or as built dates, P3 or P6 no longer calculates the longest path or critical path.

Regards,

Daniel

From AACEI RP 29R-03

It is impossible to accurately determine the as-built critical path by using only conventional float calculation on the past portion (left) of the data date. Because of this technical reason, the critical set of as-built activities is often called the controlling activities as opposed to critical activities.

For more on this suggest start by looking on this reference.

Just for fun; what if an activity that spanned two updating periods was critical on the first but no longer on the second period? Does it belongs to the As-Built critical path?

Hi Rafel,  

I need more information from you in order to answer correctly.  But if you mean if an activity is critical on first updating period not on second, is it still critical activity?

My Answer:No, it doesn'.  Because it is possible that another activity has become driving on the second update and pushes this activity out of the critical path.

Thanks.

Amir,

C. Identifying the As-Built Critical Path

At Ron Winter site you will find a more detailed procedure than the description on the AACEI document. You will also fing that the Collapsible as Built is an alternate way to find it.

It is time consuming and because at the moment I am involved with a procedure that depends on the Collapsible as Built for me at the moment it is enough with it. In our case we do not have any intermediate nor final updates so we depend only on the Collapsible As-Built if we are to use a modeled method.

If last update fixes prior computation of critical path does it means contemporaneous delay analisys is wrong? Does this means that you must wait until the end to figure out true critical path at the moment because it will be fixed when considering future critical paths, that there is a unique absolute critical path?

Maybe it is a set composed of all activities that at any given time were critical, perhaps day by day while controlling activities would be a subset of this.

Best regards,

R Davila