Boarding (or disembarking from) a vessel in the unprotected sea, sometimes without the chance for the vessel to make a lee, is always a risky situation. The pilot boat has to come alongside a moving ship and the pilot will have to climb that rope ladder, taking into consideration the swell that keeps the pilot boat going up and down while alongside and the natural ships motions (specially yawing, pitching and rolling).
There are of course safety procedures to be followed and mandatory rules to be met. These latter are explained in IMO Resolution A889/21 sect. 2, about positioning and construction of pilot ladders. Keep in mind that pilots are required to climb and descend numerous pilot ladders throughout a normal working day, so it is expected that those ladders meet some criteria on their design, otherwise it would be much more dangerous if, for some reason, pilots would meet different space between steps, for example…
In spite of all these regulations and procedures there are, every year, pilots that fall into the water, some with fatal results.
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