On April 17, 1996, about 1455 Alaska daylight time, an amphibious float equipped Cessna 206G, N244PL, collided with terrain about 3 miles southwest of Whittier, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country on-demand passenger flight under Title 14 CFR Part 135 when the accident occurred. The airplane, registered to and operated by Jim Air Inc., Anchorage, Alaska, was destroyed. The certificated commercial pilot and the sole passenger received serious injuries. Instrument meteorological conditions prevailed. VFR company flight following procedures were in effect. The flight originated from Main Bay Hatchery, about 26 miles southeast of Whittier about 1400. The operator reported that the airplane was returning to Anchorage via Portage Pass (oriented from northeast to southwest) in the area of Whittier. The company reported the flight overdue at 1730. A company airplane then located the accident site at 1,100 feet mean sea level (msl) about 1758. The airplane's left wing and the floats separated from the fuselage. The pilot reported the weather conditions at the point of departure were a 1,000 foot ceiling with visibilities of 6 to 9 miles in a light mist and calm seas. About 8 miles from Whittier, the pilot indicated that the ceiling was 3,000 feet. He climbed to 2,000 feet and proceeded toward Portage Pass. As the flight approached the pass, the visibility began decreasing in light rain drizzle and haze. The pilot began to turn back toward Whittier but then noticed that he could see Portage Glacier, about 2 miles from his position. The airplane then entered a whiteout condition. The pilot indicated that he lowered the wing flaps and entered a 40 degree bank to the right to begin a 180 degree turn away from the pass. About 2 seconds later, the right float of the airplane struck snow covered terrain. The airplane came to rest upright, on Shakespeare Glacier. The passenger reported that after departing Main Bay, the flight proceeded toward Whittier about 500 feet above the water under overcast skies. As the flight approached Portage Pass, the pilot climbed the airplane to about 1,500 feet. The passenger indicated that forward visibility decreased to zero in the clouds. The airplane collided with rising terrain to the left of the pass area.