Just for amusement as the question has been asked in various publications but not sure on here, whether or not the QE could dock at the Clyde Submarine Base, theoretically she can, Rhu Narrows are 240m wide and a minimum depth of 13.4m, specifically dredged for the Trident submarine, the QE beam maximum at the waterline is 39m and a draught of 11m so providing she doesn't get too sideways and is slow enough not to displace water in the narrows such to increase her draught it can be done. The big problem is that the QE has considerable windage on the beam and the prevailing winds are at right angles to the narrows so she would need probably to do at least 10 knots and the tugs would be restricted in positioning themselves to control any windage vere. Expensive if it goes wrong and blocks the exit and entry for all but two of the UK's submarine's home base