- You may also be looking for the D'Vahl-type survey ship, also used during the 20th century.
A Vulcan survey ship was a type of spacefaring vessel utilized by the Vulcan High Command for conducting survey missions during the mid-20th century.
A well-documented incident found at the Vulcan Science Directorate and Space Council, but outwith common Human knowledge, involved a Vulcan survey ship in 1957. Sent to investigate the launch of Earth's first artificial satellite, Sputnik, the Vulcan craft's impulse manifold began to malfunction during the third week of intelligence gathering, forcing the Vulcan crew to attempt an emergency landing. The vessel crash landed just outside Carbon Creek, Pennsylvania. The captain perished in the crash, leaving command to T'Mir. In addition to T'Mir, there were two other survivors of the crash: Stron and Mestral. (ENT: "Carbon Creek")