One of the U.S.S. Enterprise NCC-1701- D's primary engineering officers. In 2365, Logan was succeeded by Geordi LaForge.

While on a mission to Minos, where the Enterprise was attacked by the planet's out-of-control weapons system, Geordi assumed command of the starship while Captain Picard and Commander Riker were on the planet's surface. Logan believed, because of his superior rank over Geordi, and for because the captain did not plan for a crisis in his absence, that Logan should assume command of the ship.

Geordi refused and Logan, eventually, stood down.