19980530011391A

(.19) Acft collided in mid air with N187EH, crashed and was destroyed and the 2 POB suffered fatal inj., Juneau, AK. (.4) the air tour helicopter was at 2,100 feet MSL, and had just crossed a salt water channel when it collided with the airplane. The helicopter landed with substantial damage, and one injured passenger. The airplane was destroyed when it impacted water in the channel, and both pilot-rated occupants were fatally injured. An 18-inch portion of the airplane's right wing remained attached to the helicopter. None of the occupants of the helicopter saw the airplane prior to collision. The helicopter was on a standard tour route utilized by the company, and published in an FAA advisory pamphlet which the airplane occupants also had on board. The collision occurred at a location where the advised traffic route inbound to the Juneau airport crossed the helicopter's air tour route. The helicopter had completed crossing the channel, and was 100 feet above the upper limit of the recommended altitude for the crossing. The airplane was 100 feet above the lower limit of the recommended altitude for aircraft traveling west. This area has a high volume of VFR air tour, air taxi, andgeneral aviation traffic. The area is uncontrolled, class g, airspace, with no radar coverage. The helicopter pilot described the visibility as good. The helicopter pilot made traffic advisory radio transmissions on the common traffic advisory frequency (CTAF) for the area of the collision. This frequency was published in the Alaska supplement, the FAA advisory pamphlet for the area, and the VFR sectional aeronautical chart. The airplane's radios were not tuned to this frequency. The helicopter was illuminated with pulsating landing lights, and high visibility strobes. The airplane was configured with high visibility strobe lights on the wing tips, and two, nose-mounted landing/taxi lights, and a red anti-collision beacon on the tail. The control switches for the anti-collision beacon was found 'on.' The control switch for the strobe lights was found in the 'off' position. The position of the landing/taxi lights could not be determined. Neither pilot in the airplane had any record of flight experience in the Juneau area. (-23) N4948V, a Cessna 172 rg, being operated on federal aviation administration business by an FAA employee, departed petersburg, Alaska at 1521 adt. The airplane was three miles south of Juneau, transitioning north to the Juneau airport, along the east side of a coastal waterway when it collided with N187EH, an aerospatiale AS-350 helicopter at 2100 feet AGL. Preliminary investigation results indicate that the pilot of the Cessna took evasive action at the last second, possibly altering the severity of the collision, however, the impact tore off nearly two feet of the outboard wing section causing the airplane to lose control and spiral into the tidal area below.