" Unless they are gonna do subsea work in a hurricane DP3 is overkill for this area".
Not to get things confused here; DP Classes has nothing to do with weather capabilities, only with consequences of failure and redundancy of equipment:
The consequence class concept for Class 2 and 3 is entirely based upon redundant solutions, which make it possible to retain a minimum range of equipment and functions is in operationwhen others have failed.
Class 0 was a sort of “never mind” operations where nothing could go seriously wrong.Any vessel that could operate in DP mode at all, could not avoid meeting Class 3
requirements. That class disappeared with the introduction of the IMO Guidelines.
[I]PS> Also known as “Enhanced Joystick”[/I]
Class 1 operations are those where loss of position may cause some pollution and minor
economical damage, but excluding severe harm to people.
Class 2 operation are those where loss of position may cause severe pollution, large
economical damage, and accidents to people.
Class 3 operations are those where major damages may occur, severe pollution, and fatal
To obtain NMD DP-3 status requires 100% redundancy on ALL systems involved with the functioning of DP, incl. two separate Generator rooms, Propulsion rooms, switch board spaces etc.
The DPOs, ETO and Engine room staff have to have special training and proven knowledge of Emergency Procedures for the system, machinery and equipment involved. (Annual refresher)
Are there any vessels, aside from a few of the Drillships and some of the foreign vessel engaged in the GOM that meet these requirements?
For those who are SPECIALLY interested, here is link address to a paper presented at the Marine Technology Society way back in 1997, but still relevant: http://dynamic-positioning.com/proceedings/dp1997/dpclass_rokeberg.pdf