Many have commented on the ability of pre-galaxy class starships to saucer separate. Well, in S05 E07 of TNG you can clearly see a saucer that has been pretty brutalized in the ship junkyard. As well as perhaps a junked saucer section & star drive, minus the warp nacelles. This occurs at 25:50. Later, you see a good view of an entire complete saucer section, at 28:34.
I believe the first fragged saucer section to be constitution class, or constitution refit. The saucer + star drive - nacelles could be a lot of things, if it's even what I presume. The complete saucer has the stern saucer impulse engines of a constitution class or excelsior class, but those upper ribs that define the saucer are alien to me.
- Aha! I failed to search for that page. My mistake. Saucer separation is interesting to me so I thought I would post about it. I knew the model designers re-used designs, but I couldn't recognize the saucer designs in that episode at all. Best wishes.