Before revision: Defense Acquisition University Press, 2001 The functional flow block diagram (FFBD) is a multi-tier, time-sequenced, step-by-step flow diagram of the system ’ s functional flow.The first version of this article is completely based on the NAS SYSTEM ENGINEERING MANUAL SECTION 4.4 VERSION 3.1 06/06/06.
After revision: Defense Acquisition University Press, 2001 The functional flow block diagram (FFBD) is a multi-tier, time-sequenced, step-by-step flow diagram of the system ' s functional flow.The first version of this article is completely based on the NAS SYSTEM ENGINEERING MANUAL SECTION 4.4 VERSION 3.1 06/06/06.