Drillship

In recent years the vessels have been used in deepwater and ultra-deepwater applications, equipped with the latest and most advanced dynamic positioning systems.

[3] Drillships are not only growing in size but also in capability, with new technology assisting operations from academic research to ice-breaker class drilling vessels.

U.S. President Barack Obama's decision in late March 2010 to expand U.S. domestic exploratory drilling seemed likely to increase further developments of drillship technology.

[5] Drillships have the functional ability of semi-submersible drilling rigs and also have a few unique features that separate them from all others, first being the ship-shaped design.

Although mobility comes at a high price, the drillship owners can charge higher day rates and get the benefit of lower idle times between assignments.

[7] The table below depicts the industry's way of classifying drill sites into different vintages, depending on their age and water depth.

Some of the modern drillships have larger derricks that allow dual activity operations, for example, simultaneous drilling and casing handling.

The Chikyū has the remarkable ability to drill to a depth of 7.0 kilometres (23,000 ft) below the seabed, bringing that to two to four times that of any other drillship.