The modifications made to the Constitution class vessels are quite numerous.The constitution class vessels were given a new bridge module, it's engines were dismantled and was give a new type of engine. The new warp engine is composed of dylithium crystal giving the constitution class vessels a boost in their speed. Due to the new warp core, the warp nacelles was also removed and given a new one, these nacelles unlike the old one did not leak radiation giving the ship a more comfortable surroundings. Her armament was also revised, she was given forward and aft torpedo launcher, and a new set of phasers. The phaser banks like the original constitution class vessels are located on the upper and lower parts of the saucer section, during the refit an aft phaser bank was fitted right on top of the shuttle bay doors. To increase phaser power the phaser were rerouted through the main engine.  These modifications made the Constitution class vessels sleeker, smoother.and stronger.

U.S.S. Enterprise, NCC-1701A

• Second Federation starship to bear that name, commanded by Captain James Kirk.

U.S.S. Yorktown, NCC-1717

• Starship carrying vaccines for planet Theta VII; disabled by an alien space probe approaching Earth in 2286.

U.S.S. Eagle, NCC-956

• Ship listed on Operation Retrieve plan in Federation Council President's office.