Iliamna

The airline transport pilot of the float-equipped airplane was attempting a takeoff with the load of passengers that he had flown to the lake earlier in the day. The pilot's calculated takeoff distances for the water run and over a 50-ft obstacle were 1,050 ft and 2,210 ft, respectively. The pilot did not add a safety margin to his takeoff distance calculations. The approximate shore-to-shore distance of the takeoff path was 1,800 ft. During taxi, the pilot retracted the wing flaps, where they remained for the takeoff. GPS data showed that the airplane attained a speed of about 49 knots before impacting terrain just beyond the shoreline. The airplane's stall speed with flaps retracted was about 52 knots. Postaccident examination revealed that the left wing flap was in the fully retracted position; the right wing flap assembly was damaged. The airplane flight manual takeoff checklist stated that flaps were to be selected to the "TAKE-OFF" position before takeoff. Additionally, the takeoff performance data contained in the flight manual was dependent upon the use of "TAKE-OFF" flaps and did not account for no-flaps takeoffs. Even if the pilot had used the correct flap setting for takeoff, the calculated takeoff distances were near the available takeoff distance, and it is likely that the airplane would still not have been able to avoid a collision with terrain. The pilot stated that there was no mechanical malfunction/failure with the airplane, and he should have "done the right thing," which was to conduct two flights, each with a half load of passengers.

On September 15, 2015, about 0606 Alaska daylight time, a single-engine, turbine-powered, float-equipped de Havilland DHC-3T (Otter) airplane, N928RK, impacted tundra-covered terrain just after takeoff from East Wind Lake, about 1 mile east of the Iliamna Airport, Iliamna, Alaska. Of the 10 people on board, three passengers died at the scene, the airline transport pilot and four passengers sustained serious injuries, and two passengers sustained minor injuries. The airplane sustained substantial damage. The airplane was registered to and operated by Rainbow King Lodge, Inc., Lemoore, California, as a visual flight rules other work use flight under the provisions of 14 Code of Federal Regulations (CFR) Part 91. Dark night, visual meteorological conditions existed at the departure point at the time of the accident, and no flight plan was filed for the flight. At the time of the accident, the airplane was en route to a remote fishing site on the Swishak River, about 75 miles northwest of Kodiak, Alaska.

The commercial pilot of the float-equipped airplane was transporting passengers to a lodge at a remote lake. When the airplane did not arrive at the lake, a search was initiated, and two days later the wreckage of the airplane was located on the side of a box canyon about the 2,400 foot elevation level. The canyon is oriented approximately east-west, and the wreckage was distributed along a 100 foot debris field on the north flank of the canyon. Ground scars and wreckage distribution were consistent with the airplane impacting terrain in a steep left bank while executing a turn to reverse direction. No evidence of any preimpact mechanical anomalies was discovered.

The captain and the first officer were landing a short takeoff and landing (STOL) cargo airplane on a private, dirt and gravel surface runway. The airplane was configured for landing with 40 degrees of flaps. During the landing approach, variations in indicated airspeed and ground speed indicated windshear conditions. About 100 to 200 feet above the ground, the airplane encountered a downdraft and began to drift to the right of the runway centerline. The captain said she increased engine power and applied full left aileron and rudder, but could not gain directional or pitch control of the airplane. The right wing struck trees, short of the runway threshold, increasing the airplane's right yaw. The captain said that as the airplane neared the ground, she pulled the engine throttles off. The airplane struck the ground with the right main landing gear and right front portion of the fuselage. The airplane then pivoted to the right, 180 degrees from the approach heading. The owner of the airport reported that wind conditions from the east may produce downdrafts in the area of runway 05. He indicated that at the time of the accident, the wind was blowing from the east about 15 knots. The first officer reported the captain appeared to be attempting to maintain a stabilized approach angle by varying the pitch attitude of the airplane. A review of company training literature revealed that the airplane is especially sensitive to slight wind shear, and wind gusts as low as 5 knots when operating at low airspeeds. Pilots are cautioned that when flying the aircraft at low speeds, a large application of the aileron control may be required to maintain wings level. During gusty wind conditions, the threshold airspeed should be increased by one-half the gust factor, and any lateral displacement should be corrected rapidly. If a wing is allowed to drop beyond corrective action of full aileron, power should be increased immediately to regain level flight.

While maneuvering at low altitude to observe moose, the airplane stalled into the ground. The lodge's senior pilot stated that the lodge had no recurrent training program. Three passengers were killed while three other occupants including the pilot were seriously injured.

The aircraft got into a downdraft and collided with hilly terrain. The pilot stated that he was spotting caribou and settled into the side of a hill. According to the passengers the aircraft was about 300 feet agl prior to the descent to ground contact. All five occupants were injured and the aircraft was destroyed.

Few minutes after takeoff from Iliamna, the pilot was unable to maintain flying speed. In poor weather conditions, the single engine airplane stalled and crashed in a snow covered field. All eight occupants escaped with minor injuries while the aircraft was destroyed.

Flight 302 departed Iliamna at 1419LT with 11 passengers and 2 crew members on board. It was cleared to Anchorage on an instrument flight rules (IFR) flight plan via the low frequency airways--Red Airway 99 (Red 99) to the Kakon Intersection, and then Green Airway 8 (Green 8) to Anchorage. The flight was to maintain 7,000 ft. At 1425:20, the flight crew of Flight 302 established radio contact with Anchorage Air Route Traffic Control Center's (Anchorage Center) D2 nonradar sector controller. They reported that the flight was level at 7,000 ft and that they estimated arrival at Kakon Intersection at 1434. At 1428:35, Anchorage Center requested the flight's estimate for its arrival at Homer, Alaska. The flight crew responded that they estimated to be over Homer at 1515. The flight crew of Flight 302 did not make radio contact when they were over Kakon Intersection; however, at 1439:40 they requested of Anchorage Center, "302, we would like to file Green 8 and intercept the 192° bearing from Wildwood." Fifteen seconds later, Anchorage Center cleared the flight to proceed along the new route of flight and to remain at 7,000 ft. At 1440:50, the flight crew of Flight 302 advised, "302, we--we'll estimate Clams at 15 past the hour." Anchorage Center acknowledged the advisory. This was the last known radio transmission from Flight 302. At 1452:08, three abrupt, audible sounds were recorded on the Anchorage Center tape of incoming air-to-ground communications with Flight 302. These sounds were similar to those produced by a carrier frequency that was heard during the activation of Flight 302's radio transmitter during earlier radio communications with the Center. After several unsuccessful attempts to contact Flight 302 by several air traffic, control facilities between Iliamna and Anchorage and after the flight could not be detected on radar in the areas where radar coverage was available, Anchorage Center initiated the required actions to alert and notify appropriate authorities of a possible aircraft accident. U.S. Air Force search and rescue aircraft located the wreckage site at 1643 on September 7, 1977. The aircraft had struck a glacier face on the southwest side of Mt Iliamna at the 7,000 ft elevation. There were no survivors. Because of the rapidly changing environmental conditions on the glacier face of Mt Iliamna, recovery of bodies and wreckage was not possible.