On May 9, 10:07*am, wrote:
On Thu, 08 May 08, (Geoff *Miller) wrote:
It obviously
had some advantage over a conventional hull, but what
was it? *And why did the design fall out of favor with
manufacturers?

Side to side stability was noticeably better. It also gives you much
more room forward than a standard hull which creates numerous design
layout options for storage, casting deck, larger cuddy, etc. Most were
relatively flat bottomed aft so were able to operate in thinner water.
As to ride, the original idea was that the upward spray created by the
center hull would be trapped under the outer sponsons which would then
cushion the ride a bit. That theory held water (ugh... sorry) in some
of the Thunderbird models but most manufacturers modified the design
to a great extent and wasted that advantage. Becasue of that,
eventually, the stereotype reputation of "rough ride" developed
because most people simply don't realize that all cathedrals do NOT
ride alike. Fact is, even though the oldest Thunderbirds were rough,
they were very strong, safe and seaworthy in rough weather but you
just had to slow them down quite a bit.
Before their demise (or sale rather), Thunderbird was building
cathedrals with a deeper center hull with much smaller sponsons. Those
boats rode as well as any of their deep V counterparts. But it was too
late. The market had already concluded that cathedral = rough ride,
and even the easiest riding Thunderbirds didn't sell well.
My first Thunderbird was a 1964 (+/-) model which served its purpose
well. I was very young and could take a beating without much thought.
I later ordered a 1971 T'bird Commanche. That boat rides like a deep V
and still has the advantages of the cathedral. Since then, I've bought
and sold more boats than I can track but I've never found one as
versatile all around or one I like better than that 1971 Thunderbird.

Rick

They beat the hell out of you and they were heavy. You needed a good
size engine to push them around.