The IKS Ning'tao was a Klingon Bird-of-Prey that the aged Dahar Master Kor took into a lone delaying action against ten Jem'Hadar ships in 2375, dying to save Martok's squadron.
The Ning'tao is one of five Birds-of-Prey led by General Martok on a cavalry raid behind Dominion lines in the Deep Space Nine episode Once More unto the Breach. The squadron strikes the base at Trelka V and then has to outrun a pursuing force of Jem'Hadar warships.
Martok decides that one ship must turn back and hold the enemy long enough for the others to reach safety. Worf volunteers, but Kor, who had disgraced himself earlier in the mission when his memory failed, sedates him and beams to the Ning'tao in his place.
The ship and its crew are lost, but they delay the Jem'Hadar for long enough. Martok and his officers drink to Kor's memory and sing in his honour.