You know, I pretty much assumed the San Francisco ship yards were in geo stationary orbit above the city itself. If they were naval vessels for use on the ocean, I could understand ground construction. I suppose they could make components parts and have a super massive transporter at either site. How else would it be done? Taking parts up to docks like those seen in Enterprise
or The Motion Picture
, by somekind of futuristic tug boat perhaps? Launching a completed ship from the ground seems a bit too much, not to mention making the 24th Century's U.S.S. Voyager unremarkable.
There's a line of dialogue from ENT "First Flight" about laying the keel
for Enterprise. Perhaps this best describes what you'll be seeing in this trailer.