Neither Double Island Point nor Cape Moreton have seen anything over 25kts during the last 48hrs according to the BOM database. The stronger winds in fact were well south. The swell has been small. The combined swell and surface waves have been under 3.5m. 80NM NE of
Brisbane puts them on the edge of the continental shelf east of Noosa Heads, but with a sea running shallow to deep. The
current will have been north to south at 90 degrees to the sea. This does not at first read, appear to have the characteristics of
boat breaking conditions. Failure of a seal rather than the hull itself might be more probable.
I
recall the sinking/grounding of another L500 last year when the
saildrive was wrenched by lines caught in the props. Discussion revolved around the inadequate seal of the bulkhead between the
engine compartment and the central hull section.
I believe that arrangement on the L500 is similar to that in the 440. Each hull has two "watertight" sections. The bow
collision compartment, forward of the forward berth, is well sealed but relies on a good topside
hatch seal and closure of the stopcock that drains it to the
bilge above the
keel in the mid section which is not water tight. The bulk of the through hull fittings lie in this central section and it is here where the two
bilge pumps sit, as well as the manual
pump pickup. The
engine compartment pretends to be watertight. It too has a drain to the central section like the forward
collision section which can be isolated by a stop cock. The engine
hatch sits well above water height, but the seal may not be truly water or air tight. Although the bulkhead between engine and the central compartment is glassed in, there is a small 3 inch hole about 2 foot above waterline that allows fire extinguisher access in the event of engine fire. This should be a sealed
inspection port, but is simply a hole that could be plugged in the event of taking water from the stern if one thought about it at the time.
These stories make one nervous. They sailed across The Tasman Sea without issue (one of the world's "black spots") and come to grief in an area not know for mishap. Very glad all were safely returns to land and
family.