Sea Anchor / Drogue Sizing Calculator

Size sea anchors and drogues for heavy weather management

Length overall of the vessel. Sea anchor diameter is primarily determined by boat length and displacement.
ft
Loaded displacement of the vessel including crew, fuel, water, and stores.
lbs
Sailboats typically use parachute sea anchors deployed from the bow. Powerboats may use series drogues from the stern. Catamarans need larger drogues due to beam.
Storm: 48+ knots, survival conditions. Heavy weather: 30-47 knots. Drift: calm conditions for drift fishing or waiting.

Results

Drogue / Sea Anchor Diameterft
Rode Lengthft
Rode Breaking Strengthlbs
Bridle Lengthft
Deployment Depthft
References: Para-Tech Engineering guidelines, Pardey storm tactics. Sea anchor diameter roughly = LOA * 0.3 for storm conditions. Rode length = 10-15x boat length to sync with wave period.