The first UP3 file to be declassified is that of the Aeon "class," one of two known 29th Century Starfleet timeships. This was written up by yours truly a few years ago. I'll try to answer any questions you may have, but like I said, it's been a while.
AEON CLASS
A. Conjecture
I. History
Up until the 29th Century, Starfleet operated as it had always operated. Exploration of the Milky Way Galaxy continued, and by the 27th Century, many of the galactic powers had joined the Federation. Afterwards, Starfleet vessels mainly patroled the remaining borders and kept the peace.
By the early 29th Century, however, Starfleet was facing a crisis of sorts. Advancements in technology had made time travel more widely available than ever before. Starfleet captains had up until that point been able to handle most time travel situations, but the sheer number of them now had starships running to and fro trying to fix them.
At the same time, all of the paradoxes made in the past, even those presumed "fixed" by Starfleet, began to take their tole on the fabric of space-time. Temporal anomalies began to sprang up across the galaxy, especially in areas of fixed time travel devices, such as the Guardian of Forever, and in the territories of those whose inhabitants have had temporal-based technology for some time, such as the former Krenim Imperium.
To combat these dual threats, Starfleet and the Federation Bureau of Temporal Investigations began to look into the idea of ships specifically designed to both apprehend temporal offenders and repair damage to space-time by properly fixing past paradoxes, manned by those well-versed in temporal physics. Not long after, construction began on the very first timeships.
Several different timeship classes were created, each for specific types of missions. The Aeon class was designed for missions in which small but significant quantities of Starfleet hardware would have to be transported through time. Also, it would be small, in order to escape notice in situations in which knowledge of its presence by natives of other timeframes would alter the timeline. Thus, the Aeon class became a small one-man ship, armed with molecular disruptors, capable of travelling through time via artifically generated temporal rifts.
The Aeon class, however, was deemed to be mostly a failure by Starfleet due to the fact that the relatively autonomous captains of these ships tended to overstep their bounds too often. One of the last (and most famous) examples of this was the Aeon/Voyager time loop, in which the Aeon's Captain Braxton nearly destroyed the 24th Century Starfleet vessel Voyager. Finding fragments of debris from Voyager in an explosion which destroyed 29th Century Sol System, Braxton attempted to destroy Voyager in the 24th Century. What Braxton did not know is that that very act triggered the loop in which Earth would be destroyed.
II. Notable Ships of the Class
UTS Aeon NCC-429840851 Status: Decommissioned in Current Timeline. UTS Epoch NCC-429843440 Status: Active in Current Timeline. UTS Pendency NCC-429846205 Status: Decommissioned in Current Timeline. UTS Anachronism NCC-429846477 Status: Active in Current Timeline. UTS Interregnum NCC-429854309 Status: Active in Current Timeline. UTS Aoristic NCC-429864064 Status: Destroyed in Current Timeline.
B. Canonical Appearances and Information
The true name of the Aeon class is unknown, as only one ship of this class (the Aeon itself) has ever been seen. The Aeon was seen in Star Trek: Voyager's episodes "Future's End" and "Future's End, Part II." The registry number for the Aeon was not seen, so the above number is conjectural.