USS Etel Adnan
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USS Etel Adnan
Star Trek: The Next Generation - Ambassador Class LCARs by Mike Okuda ('Yesterday's Enterprise')
fleet over Andoria
(commission)
A lack of Constitution class in TNG?
This is Head canon / Non Canon - These are my thoughts as to why why the Constitution class doesn't continue into TNG, but Miranda and Oberth do.
When the Excelsior broke the then maximum warp-barrier, it created the new Warp speed scale we see in TNG. This "TransWarp" would eventually become the standard default over time, leading it to be shortened to "Warp" For any starship class to remain viable in this new era of speed, it had to be on par with at least the low to medium end of the new scale.
Naturally Starfleet sought to do a fleet wide refit, but not all the ships were suitable. The stresses of the new warp speed were greater than most had been developed for.
The Miranda class was relatively recent, with a more modern and robust hull. Also its compact shape required a smaller warp bubble, allowing the new warp systems to work within the class's power limits.
It takes time to design a new type of starship - especially with such a big warp technology shift. This is why there are so many Miranda variants and off-shoot classes. It is simpler to build up the fleet from a known design as a base.
The Oberth class is a small compact ship, and so like the Miranda class, it had smaller warp bubble power requirements. It survives all the way into TNG because of its ability to be retrofitted for the new warp tech - swapped out the coils, core and control systems.
Obeths are not an ideal starship - as well as its well known lack of modern defences, its systems had a habit of burning out under strain. Almost all Oberth ships at one time or another had to be towed back to Spacedock.
Starfleet should have replaced these ships with something more robust, and maybe they tried. Its possible that the Oberth replacement was ready to go, after the usual extensive and expensive development period. But what if it was developed before the Excelsior? The replacement class may have not been compatible with TransWarp.
Starfleet would have been left with a science ship design that would have far less warp performance than its upgraded predecessor. In the end, upgrading the Oberth class was the only possible option. Also with the sunk costs into the replacement, there would be less of a desire to restart the design process for another Oberth successor. Ultimately keeping the Oberth class ships running as long as possible would be a more economic move.
The Constitution class is a very old ship by this point. It had already had been refitted to the maximum speed the space-frame could handle. It would have torn itself apart at TransWarp, which is why the "Great Experiment" opted for a new ship over the reliable Constitution.
With its duties to be assigned to faster ships, it could have still limped on working within Federation space, but it would have been well over-spec and over staffed for these lesser duties.
With the end of Klingon hostilities, Starfleet took the opportunity to decommission ships that couldn't be upgraded. It would be many years before it was possible to design Constitution style vessels that could withstand the new warp scale - culminating in the Ambassador class.
Trans World Airlines, 1982
#500
"What's my favourite ship? Spirk? Qcard? Sevenway?
Nah, it's probably just the Enterprise-C! The Ambassador class never got enough screentime!"
“Let history never forget the name… Enterprise.”