I guess it all comes down to intent vs. fitting it into the overall universe. Intent must of course be taken with a grain of salt, but can provide useful clues overall for fitting things into place.
The TSFS script says she's a mid-size Federation science ship. She was performing scientific research, so that seems like a no-brainer. Plus, mid-size to what? The Enterprise
? The Excelsior
? Or something bigger we never saw? I expect the intent was "smaller than the Enterprise
The registry number, I admit, is less than conclusive. The overall pattern in Trek seems to be sequential registries. If NCC-1701 is launched in 2245 (assuming Capt. April existed), and NCC-2593 (Hathaway)
by 2285, then surely NCC-638 would have been launched at least sometime before 2245... more than 10 years anyway. The problem with having there be some great reset in the early 23rd century means that registry numbers seem to get scarily high scarily fast. Plus, conjecturally (unless it was stated in dialog and I"m forgetting) we have the NCC-173 in service at least
by 2167 to be lost the same year. And, not to throw the Kelvin
into the mix, but the Kelvin
is NCC-514 and in service by 2233 pre-temporal mumbo jumbo.
So you have at least:
0176 - 2176
0514 - 2233*
1701 - 2245*
2593 - 2285
You have, more or less, the registries jumping by 2400 in about 100 years, again assuming sequentiality. That would place NCC-1300 around 2235, and, NCC-600 circa 2200 in my admittedly rough estimation.
Problem with the Kelvin
, of course, is that we don't actually know when she was launched. Nor do we know whether the Oberth
had been refit or not by the time we see the Grissom
At any rate, a 70-year-old Grissom
isn't too far out of line with the mothballed 80-year-old Hathaway
, especially if the Oberth
's design is newer and/or simpler and easier to maintain.