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JETFOIL Mini-Encyclopedia

How does the Jetfoil turn head without a rudder?

While in FOILBORNE operation the Jetfoil turns head using flaps. The port and starboard flaps of the aft foil are operated up or down setting each side opposite direction first, then the Jetfoil lists and starts turning. Accompanying with this motion, the forward strut rotates toward turning direction, so that the Jetfoil can provide a smooth turning.

Reverser and deflector

While in HULLBORNE operation the Jetfoil can turn head using deflectors and reversers. The water jet direction is changed to port or starboard by the deflector and to forward or aft by the reverser. The Jetfoil has two water jet propulsors, so the Jetfoil can smoothly proceed to any directions combining two streams of water jet. The captain can brings the Jetfoil alongside a pier or leave a pier controlling water jet only by operating the helm and the throttle levers. The bow thruster also makes it easier for the captain to operate the Jetfoil even in a narrow harbor.

Are there any problems when the Jetfoil collides with floating objects?

As the Jetfoil can stop immediately like a car within short distance in case of an emergency and has a quick response to steering, it is easy for the captain to avoid floating objects.
Even when the Jetfoil collides a big floating object, the hull of the Jetfoil can be protected by the energy absorbing devices fitted on the forward and aft struts. 
With big impact on the forward strut (a support of a submerged foil), it swings afterwards to absorb the impact with the help of energy absorbers. 
With big impact on the aft strut, shear pins (fuse pins) which fasten the strut to the hull breaks and then the aft strut swings afterward to absorb the impact.
Once those shock absorbing devices work, the Jetfoil cannot continue FOILBORNE operation but can keep HULLBORNE operation to the nearest port. When the impact is small, the floating objects are kicked out by the strut and the ones such as logs are cut by the strut.

30cm diameter logs cut by the strut of the Jetfoil

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