Transverse Cross-Section & Metacentric Vector
Heel: 0.0°
GM (Metacentric Ht) Req > 0.35m
0.82 m
KG (Vert. Gravity) Keel Ref
0.68 m
KB (Vert. Buoyancy) Centroid
0.34 m
Freeboard Gunwale Imm.
0.55 m
Passenger Weight Distribution (80kg / Person)
6 Pax / 480 kg
Main Deck (Z = 0.70m)
6 Pax
3
3
Upper Flybridge Deck (Z = 1.70m) ⚠️
0 Pax
0
0
0 kN·m
0.0°
GZ Righting Arm & Heeling Curve
GZ(θ) = GM·sin(θ) + BM/2·tan²(θ)·sin(θ)
USCG 46 CFR Part 171 Compliance Engine
PASS / COMPLIANT
Transverse Metacentric Height (GM ≥ 0.35m)
PASS
Positive metacentric height prevents spontaneous rolling.
UPV Uninspected Passenger Limit (≤ 6 Pax)
PASS
Small commercial craft strictly capped unless COI certified.
Minimum Reserve Freeboard (≥ 0.30m)
PASS
Prevents gunwale submergence during harbor chop.
Downflooding Margin (> Heel Angle)
PASS
Hull deck edge remains above water ingress boundary.
Dynamic Stability Area (≥ 0.055 m·rad)
PASS
Reserve energy to absorb wave rolls up to 30°.
Accident Physics Brief: Overcrowding small recreational hulls and elevating passenger weight to upper flybridges dramatically raises KG, reducing or inverting GM. When passengers rush to one gunwale during wake encounters, vanishing righting arm GZ ≤ 0 leads to instantaneous non-recoverable capsizing.