Davit & Crane Load Calculator

Calculate davit loads, moments, and required safe working loads

Dry weight of the dinghy or tender including any permanently installed equipment, fuel, and water that may be trapped.
lbs
Weight of outboard motor if lifting with dinghy. Set to 0 if motor is removed before hoisting.
lbs
Horizontal distance from davit pivot point to the lifting point (block or hook). Measured when boom is at operating angle.
ft
Angle of the boom from horizontal. At 0 degrees the boom is horizontal (maximum moment). Typical operating angle: 15-45 degrees.
degrees
Minimum safety factor for marine lifting. ABYC recommends 4:1 for standing rigging, 5:1 for general lifting. Use higher for dynamic loads at sea.
:1

Results

Total Lifted Loadlbs
Moment at Baseft-lbs
Required SWLlbs
Wire Rope Size
Block Rating Neededlbs
References: ABYC H-41 Davit standards, ASME B30.7 crane safety. Dynamic load factor of 1.25 applied for vessel motion. Wire rope sized at 5:1 safety factor minimum.