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| CHAPTER 9—Float and Ski Equipped Helicopters
AUTOROTATION An autorotation to water is similar to one performed on a hard surface except that during touchdown, the helicopter is kept in a slight nose-high position. For greater safety, slow to around 5 knots of forward speed. However, if this is not possible, maintain a slight nose-high attitude and full-up collective to allow the floats to plane until the speed decelerates below 5 knots. As the helicopter settles to the surface and slows to zero knots, level the helicopter with cyclic and lower the collective. Do not lower the collective or level the helicopter until the speed has reduced sufficiently or the floats may tuck causing the helicopter to capsize. Hold a pitch attitude that keeps the tail from contacting the water. Autorotations to smooth, glassy water may lead to depth perception problems. If possible, try to land near a shoreline or some object in the water. This helps in judging altitude just prior to touchdown. SHUTDOWN AND MOORING Although a helicopter can be moored prior to shutdown, it is preferable to fly to a landing spot on the dock or shore prior to shutting down. The helicopter can then be parked there. If mooring is the only option, be aware of any posts or pillars that might extend above the main dock level. Even though there may be plenty of blade clearance when the rotor is at full r.p.m., blade droop due to low r.p.m. could cause the blades to come into contact with items on the dock. Also be aware of wind and waves that could tilt the helicopter and cause the blades to contact objects. If near an ocean or large body of water, tides could change the water level considerably in just a few hours, so anticipate any changes and position the helicopter to prevent any damage due to the changing conditions. When mooring the helicopter prior to shutting down, arrange the mooring lines so the tail cannot swing into objects once the rotors stop. Some pilots prefer to moor the helicopter nose in to protect the tail rotor. If there is sufficient room to allow for drift and possible turning or weathervaning, the helicopter may be shut down on open water, but wind and water currents may move the helicopter a considerable distance. When shutting down on open water, do so upwind or upcurrent and allow the helicopter to drift to the mooring buoy or dock. It might be necessary to use a paddle to properly position the helicopter. Because of the great danger from the main rotor or tail rotor of the helicopter to personnel, docks, or vessels, pilots should never attempt to water taxi up to a dock or vessel. In addition, loading or unloading passengers or freight from a partially afloat helicopter with the rotors turning is extremely dangerous. When loading or unloading passengers, the helicopter should be resting on a hard surface, either on the shore or on a helipad on a dock or on a boat. Passengers should always:
GROUND HANDLING On helicopters equipped with floats-on-skids, ground handling usually can be performed with normal or slightly modified ground handling wheels. With the ground handling wheels kept onboard, the helicopter can be handled at any landing facility. On helicopters equipped with skids-on-floats, the helicopter must be transported by a special dolly or wheeled platform on which the helicopter lands. Unless a dolly or platform is available at the destination, the aircraft usually remains where it lands. SKI EQUIPPED HELICOPTERS Ski equipped helicopters are capable of operating from snow and other soft surfaces that might otherwise inhibit conventional gear helicopters. [Figure 9-6] Snow can greatly reduce visibility causing pilot disorientation; therefore, special procedures are used when operating in snow.
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