Crossfield class

The Crossfield class was a type of Federation vessel, a starship class in Starfleet service in the 23rd century. By 2256, a ship of this class looked fresh out of spacedock. 

Technical data
The design consisted of a saucer section made of a central sphere and two rings, a wide triangular secondary hull, and two elongated warp nacelles. The navigational deflector emitted blue light and was mounted at the front tip of the secondary hull. The wide, flat shuttlebay was situated at the rear of the triangle, between the back-sweeping nacelle pylons and impulse engines.

A Crossfield was capable of conducting over three hundred scientific studies simultaneously. Based on that, former Commander Michael Burnham concluded the USS Discovery (NCC-1031) was either a science vessel or a warship. The ship's armament included phase cannons, phasers, and photon torpedoes. 

In the 2360s decade, a B-24-CLN-type vessel resembled the Crossfield class, although both saucer section and nacelles were rounder, and lacked negative spaces. 

Service history
At least two Crossfield-class starships served as testbeds for experiments to end the Federation-Klingon War of 2256, the USS Discovery (NCC-1031) and the USS Glenn (NCC-1030).