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.