The USCG says 220,000 bbl cargo which is 35,000 m3.
The water temp was a surprisingly high 74F,
Air temp 55 to 65F.
Brittle fracture can be ruled out.
The CTX believes that in this case the emphasis on the change
in the loadline regulations is misplaced.
As long as the Trim and Stability Booklet did not change,
the stress limits along the hull were the same before and after the change.
It is true that the new Loadline Regs may have
made it easier to load the ship up to the stress limits.
No mention of tank coating,
and ballast was being rotated to even out wastage.
It is pretty clear that all the tanks were uncoated.
5P and 5S were empty on this trip,
so it is very likely that these two tanks
were part of the ballast tank rotation.
The USCG's stress estimation does not seem
to have worried about the shear stress in way of 5's.
The USCG estimates as-built stresses
could easily have been 80 pct of yield.
The USCG also finds sister ships 25 to 30 pct wasted
and in one case (Texaco Wisconsin) 40 pct.
The USCG figures this ship had similar numbers
although some tanks had not been inspected for more than 2 years.
And then says corrosion was not a factor.
The NTSB in its carefully worded conclusion
is slightly more forthcoming.
The CTX thinks this is patent nonsense.
The USCG is in a bind.
Since this was an American flag ship, at least in 1971,
the USCG was responsible for inspecting the ships.
If the ship was lost because of lousy steel condition,
then part of the blame lies with the Coast Guard.
At this point the USCG is investigating itself.
The CTX is quite confident
in making steel wastage the primary cause
of this hull failure.
The wastage was combined with a marginal as-built stress pattern.
The failure probably started at some crack
which very quikcly propagated through the weakened structure.
In the end the loss of the Texaco Oklahoma changed nothing.