Protectorate ringship

The Protectorate ringship was a Vulcan Protectorate heavy cruiser starship class in service since the 22nd century. The vessel's notable feature was the coleopteric warp drive. A Protectorate ringship was a match for a Federation heavy cruiser and a Compact warship. 

Specifications
The ringships of the Vulcan Protectorate were direct descendants of the - and -classes in service by the Confederacy of Vulcan in the 22nd century. By the 2270s, Protectorate ringships were technologically advanced and incorporated Vulcan and Romulan technologies. However, they were less advanced than a Federation Starfleet Constitution-class starship because the Federation benefited from a century of cooperation and cross-pollination of its more than one hundred member worlds.

Protectorate ringships were armed with phaser banks and Romulan plasma torpedo launchers. Shields and weapons were a match for Federation and Klingon-Andorian Compact warships. Unlike the latter, the Vulcans' aptitude for scientific research resulted in the inclusion of a science department aboard Protectorate ringships.

Ringship crews were multispecies and included Vulcans, Romulans, Denobulans and Mazarites. 

History
On stardate 7583.5 (June 2274), the VHC investigated the confluence drive of the Vedala asteroid in the Sol system. By removing one of the engines, the drive was triggered. Although the Muroc had left the system, the confluence drive replaced the Muroc with the primary universe starship USS Enterprise (NCC-1701).

The Vulcan security vessel VHC attacked the Enterprise when it held the Federation ship responsible for the loss of the Muroc. Meanwhile, the Muroc's crew worked together with the Federation Department of Temporal Investigations to enable its return. Commander Spock and Subcommander T'Pring devised a means of communication with the Protectorate's timeline.

The crews of the Enterprise and the Protectorate ringship fleet worked together to activate the Vedala's asteroid. Unfortunately, the Klingon-Andorian Compact attacked in response to Enterprise's earlier escape from Chavas III. In the ensuing battle, KAC vessels destroyed at least three Protectorate ringships. However, the experiment was a success, and the Muroc and Enterprise traded places again.

By the 2380s, the Vulcans had reformed by unearthing the ancient Kir'Shara artifact and made peace with the Andorians and the Klingons. However, radical elements perpetuated the anti-Vulcan KAC. When the Compact warship Thorn of Justice attempted to invade the primary universe in the 2270s, Commander T'Pring arrived with an advanced, silverly ship and disabled the Thorn of Justice. 

Known vessels

 * VHC
 * VHC
 * unnamed Protectorate ringships
 * T'Pring's ringship