Aniak

On May 28, 2020, about 1600 Alaska daylight time, an Aero Commander 500S airplane, N909AK sustained substantial damage when it was involved in an accident near Aniak, Alaska. The pilot and three passengers sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 public aircraft flight. The airplane was owned by the State of Alaska and operated by the Division of Forestry. According to the pilot, after arriving in Aniak, he had the local fuel vendor's ground service personnel refuel the airplane. He then signed the fuel receipt, and he returned to the airplane's cockpit to complete some paperwork before departure. Once the paperwork was complete, he then loaded his passengers, started the airplane's engines, and taxied to Runway 29 for departure. The pilot said that shortly after takeoff, and during initial climb, he initially noticed what he thought was mechanical turbulence followed by a reduction in climb performance, and the airplane's engines began to lose power. Unable to maintain altitude and while descending about 400 ft per minute, he selected an area of shallow water covered terrain as an off-airport landing site. The airplane sustained substantial damage during the landing. The fueler reported that he was unfamiliar with the airplane, so he queried the pilot as to where he should attach the grounding strap and the location of the fuel filler port. Before starting to refuel the airplane, he asked the pilot "do you want Prist with your Jet" to which the pilot responded that he did not. After completing the refueling process, he returned to his truck, wrote "Jet A" in the meter readings section of the prepared receipt, and presented it to the pilot for his signature. The pilot signed the receipt and was provided a copy. The fueler stated that he later added "no Prist" to his copy of the receipt, and that he did not see a fuel placard near the fueling port. A postaccident examination revealed that the reciprocating engine airplane had been inadvertently serviced with Jet A fuel. A slightly degraded placard near the fuel port on the top of the wing stated, in part: "FUEL 100/100LL MINIMUM GRADE AVIATION GASOLINE ONLY CAPACITY 159.6 US GALLONS."

The pilot departed on a positioning flight during dark night, marginal visual meteorological conditions. A witness, who was waiting for the airplane at the destination airport, stated that shortly after the pilot-controlled airport lighting activated, a snow squall passed over the airport, greatly reducing the visibility. The accident airplane never arrived at its destination, and a search was initiated. The airplane’s fragmented wreckage was discovered early the next morning in a wooded area, about 2 miles from its destination. A review of archived automatic dependent surveillance-broadcast (ADS-B) data received from the accident airplane showed that the pilot departed, and the airplane climbed to about 700 feet above ground level. The airplane remained at about 700 feet for about 3 minutes, and then entered a shallow right-hand descending turn, until it impacted terrain. On-site examination of the airplane and engine revealed no preaccident mechanical anomalies that would have precluded normal operation. The cockpit area was extensively fragmented, thus the validity of any postaccident cockpit and instrument findings was unreliable. Likewise, structural damage to the airframe precluded the determination of flight control continuity. A postaccident examination of the engine and recovered components did not disclose any evidence of a mechanical malfunction. Given the witness account of worsening weather conditions at the airport just before the accident and the lack of mechanical anomalies with the airplane, it is likely that the accident pilot encountered heavy snow and instrument meteorological conditions while approaching the airport. It is also likely that the pilot became spatially disoriented during the unexpected weather encounter and subsequently collided with terrain.

The commercial certificated pilot was returning from a remote village after a round robin flight of about 130 miles over a frozen and snow-covered river. He was in cruise flight about 500 feet agl, but then circled while holding between 6 or 7 miles east of his destination airport, awaiting a special VFR (SVFR) clearance. The weather condition in that area was about 1 mile visibility, with a ceiling of about 1,000 feet agl. After receiving his SVFR clearance, the pilot flew toward the airport, but the engine fuel pressure began fluctuating. The engine rpm began decreasing, along with the airplane's altitude. The pilot switched fuel tanks, selected full flaps, and prepared for a forced landing. He said the weather was near white-out conditions, but he could see the bank of the river. After switching fuel tanks from the left to the right tank, the engine power suddenly returned to full power. He applied forward flight control pressure to prevent the airplane from climbing too fast, but the airplane collided with the surface of the river. The airplane sustained structural damage to the wings and fuselage. At the time of the accident, the ceiling at the airport was 600 feet obscured, with a visibility of 1/2 mile in snow. Neither the fuel status of the accident airplane, nor the mechanical condition of the engine, were verified by either the NTSB or FAA.

The air taxi pilot had flown to a remote airstrip and lodge in a company airplane to go hunting. He was scheduled the next morning for a flight from his company's base of operations, his original departure airport. According to a hunting guide at the lodge, the pilot departed the lodge's airstrip about 0608, with a load of revenue cargo. A few minutes later, the guide heard the sound of an airplane, and then a loud impact. The guide could not see the wreckage because it was too dark outside. He departed in his own airplane, but entered clouds shortly after takeoff, and had to return. The guide commented he thought the accident pilot was trying to return to the lodge airstrip because of the poor weather and darkness. The wreckage was located on a nearby mountain in daylight hours after the cloud cover had dissipated. Post accident inspection disclosed no evidence of any preimpact mechanical anomalies with the airplane. Official sunrise was 0813; official civil twilight was 0730. The time of the accident was approximately 0615.

The cargo flight was en route, when a fire erupted in or near the #3 engine. During subsequent emergency procedures, the flight crew pulled the fire handle first. Later, they feathered the #3 engine. The fire did not extinguish. During an attempt to land at a rural, intermediate airstrip, while the airplane was in the traffic pattern, witnesses saw fire coming from the area of the #3 engine. They stated the right wing buckled upward, and the airplane crashed. Examination of the wreckage revealed a failure of the master rod in the front bank of cylinders of the #3 engine. Metallurgical tests revealed a crack in the top of the master rod head, which had resulted from corrosion pits. The side of the master rod head was measured and found to be out of round. The master rod shank also fractured due to fatigue. The operator's training procedures and the Douglas Aircraft emergency checklist procedures, required that the engine's propeller be feathered first, and then the fire extinguishing system to be activated. According to information derived from the airplane's cockpit voice recorder, the flight crew reversed that order. The effectiveness of the fire suppression system is diminished if the propeller is not feathered first.

The pilot reported that while in cruise flight looking at birds out the left side cockpit window he observed peripherally a 'white flash' fill the right side of the forward wind screen followed immediately by an audible 'thump'. The airplane began an uncontrollable descent and yaw to the right. The engine continued to run smoothly. Advancing the engine power controls had no noticeable effect on his ability to arrest the descent. The NTSB investigator in charge visited the accident site. No evidence was found of a bird strike. The accident site was surrounded by tall (white) birch trees. The pilot stated that he was not sure what he struck and that it could have been a tree.

After takeoff from the gravel airstrip at Anchorage-Lake Hood, the single engine airplane encountered difficulties to gain height. It struck a lumber stack, a fence and crashed in flames onto a parking lot where five cars were damaged. The pilot, sole on board, was killed. He was en route to Aniak on a cargo flight.

During the takeoff roll on runway 20 at Anchorage-Intl Airport, the pilot-in-command realized the takeoff was not possible so he decided to abort. Unable to stop within the remaining distance, the aircraft overran, rolled for 689 yards then collided with trees and came to rest. All six occupants escaped uninjured while the aircraft was damaged beyond repair.