At one point, Cedre puts the spill at 5000 tons, at another 6000 tons.
This is a very rare collision between two loaded tankers,
This collision exposes an ambiguity in the Rules of the Road.
one ship read this as a crossing situation,
the other as an overtaking.
They did not talk.
The Glory did turn slightly to port,
about two minutes before the collision
to move further away from a coaster she was overtaking.
This is probably the source of the BBC "third ship"
but this does not seem to have had any real impact
on the collision and may have actually helped a bit.
The Allegro did turn to port at the last minute
and then back,
but Cahill says this was interaction effects.
Only attempt at communication were some light flashes
and whistle signals in extremis.
The P Glory was on the wrong side of the Channel
to be headed for Rotterdam,
presumably to pick up North Sea pilot at Brixham.
The Allegro had to cross over the downbound lane to get to Fawley,
but in this case, this may not have been a factor.
Given the obvious errors in the BBC story,
it is hard to give this account much credance.
Neither ship would have been inerted.
Best guess is that the corner of the transom of the Allegro
penetrated the Glory in an aft starboard cargo tank.
Nigerian crude is quite volatile,
and it would not have taken much to set it off.
The pictures we have support this theory,
but not unambiguously.
The fire could have started in the engine room
or pump room, but this seems unlikely.
Need depth of penetration,
but double sides might have helped on this one.
Since both ship were at full speed,
very unlikely twin screw would have helped.