HomeCalculatorsHoltrop - Form Factor 1+k1

Holtrop - Form Factor 1+k1

Form factor 1+k1 for frictional-resistance correction per Holtrop-Mennen regression - the first step in predicting still-water resistance from hull geometry.

HoltropForm factorResistance
1 + k1
0.991 -
Formula, assumptions, and limits

Simplified coefficient c_14 = 1.0 (after-body form factor) used. Full Holtrop regression includes L_R, after-body factor c_stern, and (T_A − T_F)/L. Typical 1+k1 = 1.15–1.35.

Symbol legend

SymbolMeaningUnitSource
Prismatic coefficient - hydrostatics
Breadth-length ratio - ship particulars