Tug

Tugs are a type of starship designed to tow other large objects (e.g., inoperative ships, small outposts) over long distances. (DS9 episode: "A Time to Stand")

Transport tugs are a specialised type of tug, similar to a freighter, which carry interchangeable external container that dock externally to large autonomously-operable cargo pods (that have their own registry numbers) and tow the entire assembly to a new destination. (TOS reference: Star Fleet Technical Manual)

Tug classes

• Federation
  • Hercules-class • Hogan-class • Piper-class • Ptolemy-class

Transport tug classes

• Federation
  • Dollond-class • Doppler-class • Keppler-class • Kethkin-class • Ptolemy-class
• Klingon
  • Qexa-class
• Romulan
  • Baydron-class • Moorabbin-class • Ustalam Stelas-class

Connections

• Tug article at Memory Alpha, the wiki for canon Star Trek.