Doctor Xin Ra-Havreii was an Efrosian engineer and designer who served in Starfleet in the 24th century. For over four decades, Commander Ra-Havreii worked as a theoretical engineer at the Utopia Planitia Fleet Yards. As well as working at the "Skunkworks", Ra-Havreii spent some time as an instructor at Starfleet Academy in the early 2360s.
In 2369, upon the discovery of the Bajoran wormhole, while at Utopia Planitia, he began working on design for the Luna class. The project was suspended during the Dominion War, but renewed afterwards. He was aboard for the launch of the USS Luna in 2372, which underwent a terrible accident, killing many of the crew.
In 2379, Ra-Havreii boarded the USS Titan and requested that he remained aboard for the duration of her shakedown cruise, a request which was granted by Captain William T. Riker. He was later assigned as chief engineer following an engineering disaster which killed Nidani Ledrah.