Sequenced Downtime Analysis (SDA) is a powerful analytical tool designed to examine operability and weather downtime on complex offshore projects.
SDA post-processes multi-year hindcast data to provide robust statistical evaluation based on the project’s timelines (hour by hour) and associated multi-parameter environmental requirements during a stepwise execution. Monte Carlo routines allow various time/parameter distributions to be rapidly tested, and clearly demonstrates the likely effect on slippage on the overall project schedule. Inter-annual variability in downtime can be quantified and interpreted within a climatology context.
A Sequenced Downtime Analysis provides:
- Multiple limiting criteria considered (e.g. wind speed and vessel roll).
- Best and worst case outcomes based on historical weather.
- Clear guidance on project components with weather sensitivity.
- Quantification of the effect of project slippage.
SDA has successfuly applied to offshore and coastal engineering projects such as:
- Jackup and platform installations
- Rig moves
- Pipeline construction
- Berm construction and rock dumping
- FPSO hook ups
- ROV intervention
- Heavy lifts
- Wet and dry tows
See white paper on “Estimating weather downtime for ocean engineering using Sequential downtime analysis.‘ here.





