Supporting Poseidon AmphibWorks Corporation #TridentLS1 project we get this question at almost every investor presentation.
How do boats handle submerged log threats and isn't it more dangerous for submerged hydrofoil boats?
Some boats can handle minor impacts with submerged logs relatively unscathed, however severe damage or even sinking can occur with the wrong combination of speed, impact location, and log size.
Boat hull material such as Fiberglass/Composite, Aluminum, or Steel react differently to log impacts. Fiberglass/Composite can delaminate, crack or shatter on impact, aluminum might dent or split, while steel could dent but is generally more resilient unless the impact is very forceful. Older wooden hulls might suffer from splintering or structural damage.
#TridentLS1 employs the toughest workboat material known to resist such impacts, known as marine #HDPEboats so when off foils and at moderate speeds can handle collisions unscathed.
Location of Impact: If the log hits near the waterline or directly under the hull, it could lead to immediate water ingress. If it strikes propeller(s) or rudder(s), it might disable the boat's propulsion or steering.
FOR ALL BOATS, regular vigilance and precaution in log-infested waters are key for safety. If you are traveling in waters as shown in picture below, it would be wise to take precautions.
Almost all non-foil boats do not have underwater sensors and collision avoidance systems to avoid these dangers.
Many modern foil boats, compared to older models, when on foils, do in fact employ such sensor systems plus stronger materials and clever designs to mitigate damaging effects of collisions such as employing mechanical features in the foil design to safely deflect impact loads and/or allow breakaway or shear sectioned foils. #TridentLS1 has IP in this area which is quite impressive - testing will of course confirm.
The best strategy to minimize damage is for onboard collision avoidance systems (detects debris, boats, buoys, markers, shore, etc.) to automatically sense oncoming danger and immediately alter course and reduce speed to get off the foils to clear the danger area.
In some cases, the retractable foil systems may also be triggered to rapidly retract foils bringing the boat down to the water gently while simultaneously reducing the vehicle speed - in the case with #TridentLS1, its foil system/thrusters operates in all positions from fully retracted to slightly extended just beyond the hull bottom surface.
The picture below DOES NOT SHOW THE SUBMERGED LOG danger situation. It actually shows the easiest collision avoidance case.
The toughest sensing scenario for a collision avoidance system is when the log is saturated and it is submerged, not visible from the surface of the water - see this pic - https://lnkd.in/gBcnjvMN