Thomas Alan Chafin was a Starfleet officer. As an Ensign, he served aboard the USS Enterprise-D as a relief flight controller. (TNG novels: Strike Zone, Exiles, Vendetta, Imzadi, Q-Squared)

By 2381, Chafin held the rank of Lieutenant Commander. According to Casualty Report 92792382 Baker, Chafin was killed in sector 22093 during the Borg Invasion of 2381. (ST novel: A Singular Destiny)

Chafin was likely a member of the crew of the USS Malinche, as this is the only Starfleet ship known to have engaged the Borg in this sector.