[Alberta's Child]

Who was shipping the munitions on that vessel? Whose munitions were being shipped?

Not that it's relevant in this case, but under U.S. railroad regulations the shipper bears nearly all the responsibility for what they are shipping when it comes to safety, regulatory requirements, etc. -- not the carrier.

[Billthedrill]

That always was a controversial claim. The difficulty was that the small-arms ammunition that was carried (~4000 boxes IIRC) wasn't sufficient to explain the secondary explosion and probably wouldn't have "exploded" anyway (the stuff will burn). If it were artillery shells, which has long been suspected but for which there isn't really any documentation, then it would likely have been a bigger explosion. The theory that seems to make the most sense to me is some sort of a ruptured boiler or HP steam line. That and 18 knots through the water after the integrity of the hull was breached will put a lot of water in a very bad location. And, too, the secondary explosion was in a location quite apart from where the torpedo hit, which throws some doubt on the ammunition theory.

It will be fascinating to see if they actually can photograph the area in question or if there is enough left to draw any conclusions. If the sea bed were littered with artillery projectiles that'd be pretty conclusive but that's an awful lot to expect after nearly 100 years in shallow water.

[LAforme2008]

US regulations wouldn’t apply. It was a British ship operated by a British company sailing to a British port.