GRP Yacht Underside Implosion

[landmarine]

We own a 25 foot Trailer Yacht that appears to have imploded by about 20mm near the aft part of the keel. The vessel is 20 years old but in good condition. I think this implosion may have occurred while being trailered without a tie down strap fitted. Since the incident we have had the underside faired (at great expense) but it's still not perfect (batten reveals a max deviation of around 7-8mm). Has anybody heard of such a thing occurring before, and is it possible to correct say by slinging the boat carefully and adding water internally slowly say? ?

[scottyt]

do not try to sail that boat. if the glass aft of the keel flexed and stayed that much fairing wont fix it. it really need some exploratory surgery to see if the glass is delaminating, or what damage was done. i really doubt the glass can flex almost an inch, then not pop back out with out some internal damage to the lay up.

get a good fiber glass guy or a surveror to look at it. you will probably need a drill a hole thru it to "see" the internal layers of glass. luckly patching a 1 inch hole is pretty easy

[timebandit]

What kind of boat?

[sailingdog]

I'd second what the they said... you need to have the laminate and structure checked out to see if there is any structural damage. It would really help if you said what kind of boat this was.