3.2.2.3. OAV and jack-up vessel. The operability analysis of OAVs
and jack-up vessels are dependent on the generated wind speed
and wave height values. If either generated wind speed or wave
height is higher than the ‘Maximum operational wind speed’ limit
or ‘Maximum operational wave height’ limit, these vessels are
required to cease the maintenance operation. In addition for jackup
vessels, the minimum weather window should be longer than
the time required for jacking-up. In this case, the minimum
weather window is defined by the consecutive time steps in
which wave height and wind speed values are lower than the
limiting wave height and wind speed for jacking operation. If the
minimum weather window is shorter than the jacking-up period,
the vessel stays at the site until the conditions are met. When the
minimum weather window is sufficient enough, the vessel jacksup.
Due to the fact that the major O&M activities require heavy
equipment lifting, wind speed at hub level is an extra limitation
for the jack-up O&M operations. As for the jacking operation, the
minimum weather window should be longer than the time
required to perform the repair or the replacement. If the
weather window is shorter than the repair period, the vessel
waits as jacked-up until the conditions are met.