Naval Service ships are required to complete dry-dock maintenance, survey and inspection, twice during each ship five (5) year cycle. An intermediate dry-dock is carried out between two and a half (2.5) and three (3) years. A full dry-dock is carried out at five (5) years.
Naval Service ships which are beyond their originally projected 30-year asset life, are dry-docked for inspection every year, in order to manage ageing hull risk.
In addition to the planned maintenance (dry-docking and refits) carried out on all vessels, there is a requirement to upgrade and refurbish vessels having regard to emerging operational requirements and changes in technology. This is referred to as a Mid-Life Extension Programme and these works aim to extend the life of a vessel and address obsolescence. The Mid-Life Extension Programme of LÉ Róisín commenced in March 2019, with an initial dry-docking phase, followed by an extended period of equipment upgrade and refit works. LÉ Niamh's extension programme is due to commence in 2020.
Notwithstanding this capital maintenance programme, Naval Service Ships are required to undertake planned routine and non-routine maintenance on plant and machinery every day, 365 days a year, regardless of whether the ship is on patrol, undertaking Maritime Defence and Security Operations or alongside the Naval Base off patrol.
These works are carried out to ensure the operational capability of the Naval Service is maintained to the greatest extent possible so that they can carry out their roles as assigned by the Government.
Detailed maintenance and dry-docking schedules have not been provided for operational defence and security reasons.