(WWI – This is also going to the Mahan list.) An interesting question
was raised, in light of the claim that the LUSITANIA second explosion
was due to the ignition of coal dust knocked into the air of the bunkers
by the single German torpedo – if a shell hits an *empty* coal bunker,
is there a chance of an explosion? My suggestion:

A shell hitting a mostly-empty coal bunker might not set off an coal
dust explosion if the buker was not open. The shell explosion itself
would possibly consume all the available oxygen in the confined
space…. but the new question is does the blast or fragments from
the shell then rupture or pierce the bulkheads of the bunker, which
would make that moot.

Also, there might well be only a critical range of dust size and amount
suspended that is actually explosive – a mining engineer might
tackle that one….

Relative to this, Bill Schleihauf posted the following

> Just a quickie, as it’s rather off-topic, but I just want to correct
> something I posted yesterday. Now that I’ve *finished* reading the
> article “What Really Sank the MAINE” by Thomas B. Allen in the Naval
> Institute’s “Naval History” magazine (April 1998 issue), the conclusions
> are that based _solely on the physcial evidence + modern computer
> modelling_ it is deemed likely that a *mine* sank the battleship,
> instead of a fire in the coal bunker. The article states that a coal
> fire certainly *could* have setoff the magazine, but the position of
> one piece of plating (basically twisted the wrong way) suggests that
> it was an external explosion (ie a mine) which was the cause.
> The article is very thorough and laden with math and engineering-
> way beyond my ken! Certainly well worth reading for those interested,
> and it does not, IMHO, end the controversy. The article does NOT get
> into a discussion of *how* a mine could have been laid, etc… a very
> important point. It should certainly be read in conjunction with the
> Rickover book “How the Battleship MAINE was Destroyed”, which goes into
> this in detail.
>
> Bill Schleihauf
> Pierrefonds, Quebec
> CANADA
> william@cae.ca

This is as Bill says off topic for WWI list, other than in the prequel
effect of the rise of the US to world power status, but since he
mentioned
it….
This evening I too read the NAVAL HISTORY article Bill S. cited, while
sitting in a medical waiting room (I have a dreadfully painful
ear infection….) Having done some of engineering work (finite
element modeling of strucutres) of the type described in the article, i
was able to
reasonably follow it – but they seem to have totally mis-stated
something I
*think* I remember from Rickover’s book. I’ll have to dig that out and
look at it again, but:

Part of the underside of the hull of the MAINE was bent UP INTO the
ship, vice down. The original investigation after the raising of the
ship, considered that proof positive that a mine, external to the ship,
was involved.

What I thought i remembered of the Rickover investigation, concluded
that the *accidental* explosion of the magazine did blow the bottom of
the ship downwards, but that the *shock wave* of the blast *rebounded*
off the harbor floor, back up to the ship, and *this* loading bent the
hull
plates in question back inwards.

The article in NAVAL HISTORY states that the Rickover investigation
said that the *inrush of water flooding into the ship* caused the inward
deformation. Not the same thing at all, and the inrush of water would
likely have a much lower load applied to the hull plating than the
shock effect.

Unfortunately, like all too many other of my books, my Rickover HOW
THE BATTLESHIP MAINE WAS DESTROYED is buried at the moment, so I can’t
look it up. But if my memory is correct, the new investigation may
have
been flawed by assuming the wrong loading mechanism in modeling this.

Nonetheless, this effect is real. A slightly related effect is noted in
various editions of THE EFFECT OF NUCLEAR WEAPONS, various years – one
will
often find the paradoxical efect of broken off trees or poles or masts
bent
TOWARDS the blast, rather than away. In essence, the blast load breaks
the structures and tilts them outward from the blast – but there is a
reaction wind back toward the center of the explosion a few seconds
later,
as the overpressure has blown so much gas outwards that the area where
the
blast occured has now become rarified, so that air tries to rush back
in, to
equalize pressure. Thus, there is a reverse, lower magnitude, counter
wind that can flip the broken structures back the other way. This is
somewhat related i suppose to the NAVAL HISTORY article’s version of the
Rickover conclusion – which again, is not what I thought I
remembered….

I am going to post this to the Mahan naval history list, and prefer
followups there, since it is off-topic for the WWI list.

-Brooks