AACE CST case studies
AACE CST · Put your knowledge to work in context.
The AACE Certified Scheduling Technician (CST) is a technician-level credential offered by AACE International and listed on the association's site under Technician Certifications, alongside the Certified Cost Technician. It is aimed at practitioners who build, update and maintain project schedules - junior schedulers, planning engineers, project controls technicians and coordinators - who want to show working-level competence rather than the advanced, professional-level knowledge expected of a PSP holder. The AACE CST case studies are 5 cases and about 2,229 words.
1The 1,850-Activity Water Plant Schedule
Northgate Utilities is expanding a 40 ML/d water treatment plant over 14 months. The contractor's first draft schedule contains 1,850 activities, most at 8-hour task level, on a single 7-day calendar.
448 words, about 2 min2Negative Float in a 21-Day Substation Outage
During development of a 21-day substation outage schedule, the scheduler links 'Replace breaker' (10 days) to 'Energize and test' (3 days) with a start-to-start lag of 10 days. 'Energize and test' also carries a start-no-earlier-than constraint of Day 15.
447 words, about 2 min3Out-of-Sequence Progress at Month-End
At the month-end update, the data date is 30 September. The schedule shows 22 activities whose successors have actual starts before the predecessors' actual finishes, and 8 activities with actual finishes but no actual starts.
443 words, about 2 min4The Critical Path That Is Not the Longest Path
At a monthly review, the contractor reports the project 35 days behind and states the critical path runs through mechanical completion. The owner's analyst finds that the longest path actually runs through electrical commissioning, but that path carries 18 days of total float because of a finish-to-finish relationship and a 10-day lag.
439 words, about 2 min5SPI Above One on a Late Project
At a portfolio review, a project shows CPI 0.94 and SPI 1.08, and the project manager reports that the project is ahead of schedule. The CPM forecast, however, shows completion six weeks after the baseline.
452 words, about 2 min