List of unnamed Vulcan survey ships.
Earth survey vessel []
A well-documented incident known to the Vulcan Science Directorate, but not to common Human knowledge, involved a survey ship that visited Earth 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.
Later, Mestral asked to be allowed to remain on Earth. Believing it would satiate his curiosity, T'Mir suggested that she could arrange for him to be on the next survey ship that studied Earth. Mestral was displeased by the prospect, believing it would not happen for another twenty years and would be limited to running statistical scans from a high orbit. (ENT: "Carbon Creek")
Earth fleet []
This survey ship was among the group of ships that welcome Enterprise NX-01 home after the Xindi incident in 2154. (ENT: "Storm Front, Part II")