Propeller damage from floating debris: accident or wear and tear?

Propeller damage from floating debris is a familiar problem on rivers, lakes and coastal waters. After a flood, branches and whole tree trunks drift downstream, and along the coast timber, nets and lines float just below the surface. A thud, a vibration, and the propeller has bent or broken blades; sometimes the shaft, gearbox or drive suffer too. Whether a claim is likely to be accepted or treated as wear and tear depends on how the damage happened: a sudden accident from outside, or gradual deterioration over a long time.

Hull policies are generally written around sudden, accidental events, and hitting debris is such an event. With us it counts as an accident, covered from Basis Plus; Basis does not cover it. Gradual damage is a different matter: worn edges, corrosion, pitting from cavitation, a propeller that has been out of true for years. With an older propeller the surveyor will look at whether the damage fits a strike, such as fresh deformation and traces of wood, or whether it is old. Depending on the policy, a deduction for the age of the part may apply. Internal damage to the gearbox or shaft with no external event is often excluded from hull cover, which is why some policies offer separate machinery cover. Read your own wording to see where the line is drawn.

If you hit something, put the engine in neutral, check whether anything is caught round the propeller, and only carry on at low revs if there is no heavy vibration; strong vibration can damage the shaft, bearings and seals and make the repair bigger. Photograph the propeller, keep the old part and, if you can, the debris, and note the time and place. Report the damage to your insurer before the repair. After floods or strong winds, slow down and keep a proper lookout, because a log just below the surface is very hard to see.

Worth remembering

Photos and the old part decide whether propeller damage is accepted as a strike.