The Pine Ridge was a T2 that broke in two off Hatteras in ballast
in a Force 9/10 storm in December of 1960.
The break was in way of the sixes, just forward of Frame 56.
The bow turned up, sank and the seven crew forward were killed
including the Captain and the Chief Mate.
The bow section stayed afloat for about six hours.
But, as always in these cases,
there was no way the forward lifeboats
could be launched.
The MBI recommended requiring life rafts on the forward house
but the Commandant did not act on this.
The stern with 29 aboard stayed afloat
and was eventually towed in,
where it could be inspected.
The Marine Board of Investigation report of this casualty
is far better than the normal USCG report.
It contains the loading pattern at the time of the sinking.
The Master had gone to a very heavy (13,460t) ballast condition
concentrated near mid-ships.
Presumably he did this to avoid putting ballast in tanks
that had not yet been cleaned.
The result was a sag numeral of 150,
one-third higher than the ABS recommended max of 100.
Even more surprising the report contains wastage numbers.
Inspection of the stern revealed that the fracture
was largely ductile,
It also revealed that the deck plate was 23% wasted,
side plate and bottom plate 17% wasted,
longtiduinal bulkheads 37% wasted,
deck stiffeners 65% wasted,
side stiffeners 60% wasted at the top
dropping to 25% at bottom,
bottom stiffeners 28% wasted.
The Marine Board very politely called this "borderline".
The ABS measurements taken a year earlier
were similar to the USCG measurements.
ABS and the USCG had inspected the vessel two months
earlier and OKed it despite the fact that
some tanks could not be inspected
because the ladders were too wasted to be used.
The owners intended to jumboize the ship
by putting in a new mid-section.
The MBI guessed that this was "in the minds"
of the inspectors and surveyors in allowing the ship to trade.