The Ship Model Forum

Nowadays passenger ships need a certificate renewal every five years, this requires a full inspection of the hull. I don't know the validity period of the certificate before WW2, but I don't think it would have been that different.

In case of the lifetime of RMS Mauretania (1906-1934) this would mean she has been drydocked at least five times. Not many more anyway, as she would have been out of service for weeks or months and therefore losing revenue. In Wikipedia I found she'd been refitted in 1914, 1921 (oil firing), 1923 and in 1928.

During WW1 she of course was refurbished twice, as a troop transport and a hospital ship, and in 1928 her interior was refurbished, these refurbishments didn't require a drydock of course but most likely she had her bottom inspections at the same time. The picture below proves the point for 1928.

_________________
"I've heard there's a wicked war a-blazing, and the taste of war I know so very well
Even now I see the foreign flag a-raising, their guns on fire as we sail into hell"
Roger Whittaker +9/13/2023

In general, Atlantic liners were usually dry docked during the winter when service was suspended.

Most books about Atlantic liners refer to a yearly dry docking. The main reason seems to have been that early antifouling paints were not that effective which would slow them down. This was especially relevant for speedsters like Mauretania. There are actually 1/500 plans available for the dock in the picture, as modernized and used by RDM from 1959 to 1984. So if you are willing to scale these plans down by 83% and do some scratchbuilding you can build this scene.
https://www.modelbouwtekeningen.nl/nl/n ... nhard.html
And some more pictures.
https://www.rdm-archief.nl/project/prin ... -droogdok/