LÉ Emer (P21)

LÉ Emer (P21) is a ship in the Irish Naval Service. The ship is named after Emer the principal wife of Cúchulainn and the daughter of a chieftain from Rush, County Dublin.

After evaluating Deirdre for 3 years, Emer was ordered in 1975. Experience with Deirdre showed a need for more engine power, better crew accommodation and improved silencing. The vessel has been modernised throughout her service life in order to take advantage of new technologies and to make life for the crew more comfortable; additions include air conditioning

She is an improved version of the sole of Class Deirdre and similar to the improved versions LÉ Aoife(P22) the Aisling. She was commissioned on 16 January 1978 and is the next vessel due to be replaced.