14 CFR § 136.11 - Helicopter floats for over water.
(a) A helicopter used in commercial air tours over water beyond the shoreline must be equipped with fixed floats or an inflatable flotation system adequate to accomplish a safe emergency ditching, if -
(1) It is a single-engine helicopter; or
(2) It is a multi-engine helicopter that cannot be operated with the critical engine inoperative at a weight that will allow it to climb, at least 50 feet a minute, at an altitude of 1,000 feet above the surface, as provided in the Rotorcraft Flight Manual (RFM).
(b) Each helicopter that is required to be equipped with an inflatable flotation system must have:
(1) The activation switch for the flotation system on one of the primary flight controls, and
(2) The flotation system armed when the helicopter is over water and is flying at a speed that does not exceed the maximum speed prescribed in the Rotorcraft Flight Manual for flying with the flotation system armed.
(c) Fixed floats or an inflatable flotation system is not required for a helicopter under this section if:
(1) The helicopter is over water only during the takeoff or landing portion of the flight, or
(2) The helicopter is operated within power-off gliding distance to the shoreline for the duration of the flight and each occupant is wearing a life preserver from before takeoff until the aircraft is no longer over water.
(d) Air tour operators required to comply with paragraphs (a) and/or (b) of this section must meet these requirements on or before September 5, 2008.