Columbia class

The Columbia-class was a type of starship which entered service with the Federation Starfleet in the mid-22nd century.

History
The Columbia-class was born out of the existing, and proven, NX class design, and included retrofitted ships such as the SS Enterprise and the USS Endeavour. It was named, at the insistence of Admiral Jonathan Archer, after the first vessel of the NX-class to be lost in action, the Columbia.

As of September 2162, the refit Endeavour was the last active survivor of the NX-class. All future vessels would be of the new Columbia-class.

Design
The most noticeable difference between the NX and Columbia classes was the addition of a secondary hull which was slung underneath the saucer section. This new hull had a deep rear undercut allowing it to be positioned in the warp field's secondary node while in flight and a more powerful, circular navigational deflector. It also housed the new, larger warp core which allowed speeds in excess of warp factor six. The extra room liberated in the primary hull by the removal of warp engineering allowed for larger senior officers' quarters.

The dorsal connector to the saucer was located where the NX's main shuttlebay used to be, so the drop bays were moved to either side of it. 

Specifications
As well as polarized hull plating, the Columbia-class featured deflector shields of Andorian design. For a while after the class was brought into service, use of the shields while at warp necessitated an adjustment of the warp field. This adjustment, due to difficulties in reconciling Human and Andorian technology, meant that warp speed was limited to just over warp factor three. The class was equipped with a tractor beam of Vulcan origin which, like the shields, took a little while to integrate into the existing systems.

Known Vessels

 * SS Enterprise
 * USS Endeavour