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 been applied to jackup and WHP installations, rig moves, heavy lifts, pipeline construction, wet and dry tows, ROV intervention, berm construction and rock dumping.