How does a fixed keel boat differ from keel+centerboard?
I am curious to understand the difference between a fixed keel boat and a keel + centerboard IF the displacement & ballast are close in both version. For example:
Valiant 40 - Keel + Centerboard (rare but it's an example only)
Displacement: 22,500 lbs
Ballast: 7,7000 lbs
Valiant 40 - Fixed Keel:
If I was to calculate all common sailboat ratios related to speed, stability, capsize risk, none is ever related to the depth of the keel, but more often to the LWL, Beam, Displacement, Ballast and Sail Area.
Therefore, what would be the drawback of purchasing a keel + centerboard sailboat for offshore cruising/sailing, versus a fixed keel one? Does it impact safety? stability? or only speed?