Safety Alert: Captains must always be aware of air draft, vertical clearance

The U.S. Coast Guard has issued a Safety Alert urging all owners and operators to ensure that they can transit overhead obstructions safely. That means always being aware of the vessel’s air draft and the vertical clearance available to sail under bridge spans and power cables.

Over the past 11 years, the Coast Guard has counted 205 air-draft-related accidents at bridges, including fixed, swing, lift and drawbridges. There have been several additional incidents in which vessels have struck power cables or other overhead objects. Towing vessel and barges are the most likely vessel to be involved in such an accident. The most common problems are failure to lower cranes or to adjust spuds.

Federal regulations require owners and operators to ensure that the person controlling the vessel understands the constraints of the vessel and voyage, including tides, currents and other dangers. The person must understand the “general arrangement of the vessel” including air draft of the vessel and barges in tow.

The Coast Guard recommends that the officer uses real data, not assumptions.

The following is Coast Guard’s entire Safety Alert:


By Professional Mariner Staff