Sea trials evaluate the vessel in a way that is impossible to detect while ashore.
Sea trials evaluate the vessel’s structural integrity, propulsion systems, rigs, and sails under realistic operating conditions to reveal hidden operational issues that are impossible to detect while ashore.
Typically arranged by the vessel owner and conducted by experienced seafarers or engineers at hourly rates, the marine surveyor’s primary role during this process is to document all mechanical and structural findings while underway.
Vessel Categories Under Inspection
Sail Yachts
Sail yachts require testing under both machinery and canvas to assess rigging stress and sail handling.
- Mast and Rigging: Check standing rigging tension, chainplates, running rigging and deck stepped (compression post) or keel stepped mast.
- Sail Handling: Deploy, reef, and tack main and headsails to test winches and furlers.
- Keel and Hull Stress: Monitor the bilge and keel bolts for movement or leaks while heeling.
- Steering Feel: Assess helm balance, weather helm, and emergency tiller operation under sail.
- Auxiliary Power: Run the engine to ensure adequate propulsion against wind and tide.
Motor Yachts
Motor yachts focus heavily on high-speed mechanical performance, vibration analysis, and system stability.
- Full Throttle (WOT) Test: Run engines at Maximum Rated RPM to check top speed and cooling.
- Cruising Efficiency: Record fuel burn, speed, and RPM across the power band.
- Engine Visuals: Scan for oil leaks, coolant leaks, and excessive exhaust smoke.
- Vibration Analysis: Feel for shaft misalignment, propeller damage, or loose engine mounts.
- Trim and Stabilisation: Test trim tabs, interceptors, or gyro/fin stabilisers for hull leveling.
