@echopapa Aus Wikipedia:
"A 2009 safety assessment by the Defence Nuclear Safety Regulator concluded that PWR2 reactor safety was significantly short of good practice in two important areas: loss-of-coolant accident and control of submarine depth following emergency reactor shutdown.[39] The regulator concluded that PWR2 was "potentially vulnerable to a structural failure of the primary circuit", .."
Rolls-Royce PWR2 in UK Astute Klasse.
Quelle: https://en.wikipedia.org/wiki/Astute-class_submarine