Accident Overview
On June 18, 2017, about 1330 Alaska daylight time, a float-equipped de Havilland DHC-2 Mk.1 (Beaver) airplane, registration N930TG, was substantially damaged in an accident near Ketchikan, Alaska. The commercial pilot and six passengers sustained minor injuries. The airplane was operated as a 14 Code of Federal Regulations Part 135 on-demand sightseeing flight.
Sequence of Events
The accident flight was a 2-hour tour purchased by cruise ship passengers as a shore excursion. The route included overflights of remote mountainous terrain in the Misty Fjords National Monument, with stops at Big Goat Lake for scenery viewing and Walker Cove for coastal brown bear viewing. The airplane landed at Big Goat Lake around 1300, and passengers were onshore for about 20 minutes. Big Goat Lake, a freshwater lake about 1,780 ft above mean sea level, is surrounded by steep, mountainous terrain.
Postaccident statements revealed that the pilot attempted a takeoff but was unsuccessful. He subsequently told the passengers, "we missed that takeoff, we are going to try again." The pilot reported weather conditions at the time of the second takeoff as an east wind less than 5 knots and a temperature of 65°F. He initiated the takeoff downwind on a westerly heading. After the airplane was established on the step, he performed a right 180° step turn to the east. Once into the wind, he applied full power. By the time the airplane reached the pilot's go/no-go decision point, it was airborne and climbing between 100 and 200 ft per minute. He adjusted flaps and power for a climb configuration, but after continuing over about three-quarters of the lake's length, the airplane "wasn't climbing efficiently." The pilot realized it would not climb above a heavily-wooded area ahead, lowered the nose, and turned left. About 130° into the 180° turn, the airplane's left wing impacted the water. Two passengers reported that during the takeoff and subsequent turn, they did not hear the engine decelerate or "turn off" until impact.
Upon impact, the floats separated, and the airplane began to sink nose-first. All occupants successfully egressed and swam to a rocky shoreline. None were wearing personal flotation devices (PFDs), which were not required by regulation for that phase of flight. One passenger estimated the swim duration as about 20 minutes and distance as "2 to 3 football fields." Another passenger found a PFD floating in its storage bag while swimming, opened and inflated it, and gave it to a passenger struggling to swim. The airplane sank to the bottom of the lake.
Post-accident Observations
Another tour company from Ketchikan, operating a DHC-2 with one pilot and six passengers onboard, conducted a welfare check after spotting the stranded occupants on the shore. That pilot landed on the lake around 1400, noted the water was not glassy with wind about 5 knots from the east, and reported no issues taking off from the lake.
The accident pilot reported to the Federal Aviation Administration (FAA) that he was at Big Goat Lake in the accident airplane about 2 hours before the accident and departed without issues. A pilot of another tour company landed at the lake shortly after the accident in a DHC-2. He reported that after takeoff, he set power to a climb setting and immediately realized it would be insufficient; he then increased power to maximum continuous and departed with no issues.
Aircraft and Operator Information
The operator reported that there were no preimpact mechanical failures or malfunctions with the accident airplane that would have precluded normal operation. The airplane was below its maximum gross weight and within center of gravity limits at the time of the accident.