Re: A mistake of delftship for yatch design

[Wild]

They all are correct. LCB means Longitudinal Center of Buoyancy. This can be either an absolute value (in your case 5.796) or a relative value in percentages. In this case the location of the LCB relativly to the mid ship section is calculated as a percentage of the waterline length. It’s easy to check with the following formula:

LCB [%]=100 * (LCB [m]– Midship location[m])/ L_WL[m]

I suspect that “Midships location” is what confusing.

Is it 0.5*LWL?
Is it coordinate with largest (underwater) cross sectional area?
Is it 0.5*LOA?
Is its coordinate from X=0
Is it from aft X coordinate of LWL?

Example:

Looking for LCB location in DS PRO (default model 12m, 3.7m, draft 0.5 m. After creating model, change draft to draft = 0.775m)

Draft = 0.775m

Coordinates from X=0

Base model LOA = 12m
1/2 LOA = 6m

LWL = 11.21m
1/2 LWL = 5.605m

Max Cross sectional Area “X” coordinate ~ @ 5.7m

WHICH ONE?

Just curious… Why in hydrostatics report DSPro does not give coordinate for largest cross sectional area? It gives the value for larges area, but not its coordinate…