Flight

A DHC-4 Caribou aircraft, registered PK-SWW was being operated by Perkumpulan Penerbangan Alfa Indonesia, on 31 October 2016 on an unscheduled cargo flight from Moses Kilangin Airport Timika, with intended destination to Kaminggaru Aerodrome, Ilaga Papua. On board on this flight was 4 persons consisted of two pilots, one company engineer and one flight operation officer. At 2257 UTC, the aircraft departed Timika with intended cruising altitude of 12,500 feet and estimated time of arrival Ilaga at 2327 UTC. At 2323 UTC, the pilot made initial contact with Ilaga Aerodrome Flight Information Services (AFIS) officer and reported that the aircraft position was at Ilaga Pass and informed the estimate time of arrival Ilaga would be on 2327 UTC. Ilaga Aerodrome Flight Information Services (AFIS) officer advised to continue descend to circuit altitude and to report when position on downwind. At 2330 UTC, the AFIS officer called the pilot and was not replied. The AFIS officer asked pilot of another aircraft in the vicinity to contact the pilot of the DHC-4 Caribou aircraft and did not reply. At 0020 UTC, Sentani Aeronautical Information Service (AIS) officer declared the aircraft status as ALERFA. At 0022 UTC, Timika Tower controller received information from a pilot of an aircraft that Emergency Locator Transmitter (ELT) signal was detected approximately at 40 – 45 Nm with radial 060° from TMK VOR (Very High Frequency Omni Range) or approximately at coordinate 4°7’46” S; 137°38’11” E. This position was between Ilaga Pass and Jila Pass. At 0053 UTC, the aircraft declared as DETRESFA. On 1 November 2016, the aircraft wreckage was found on a ridge of mountain between Ilaga Pass and Jila Pass at coordinate 4°5’55.10” S; 137°38’47.60” E with altitude approximately of 13,000 feet. All occupants were fatally injured and the aircraft destroyed by impact force.

The commercial pilot was conducting a cross-country flight to a family residence in the turbinepowered, single-engine airplane. The pilot was familiar with the route, which traversed a mountain pass and remote terrain. Before departing on the flight, the pilot communicated with a family member at the residence via text messages and was aware the weather was windy but that the mountain tops were clear. There was no record of the pilot obtaining a preflight weather briefing from an official, accesscontrolled source, and the pilot indicated to a friend before departure that he had not accessed weather cameras. Weather forecast products that were available to the pilot revealed possible turbulence at low altitudes and icing at altitudes above 12,000 ft along the route of flight, and weather cameras along the planned route and near the destination would have indicated deteriorating visibility in snow showers and mountain obscuration starting about 1.5 hours before departure. The airplane departed and proceeded toward the destination; radar data correlated to the accident flight indicated that the airplane climbed from 4,600 ft to 14,700 ft before turning west over the mountains. Text messages that the pilot sent during the initial climb revealed that the mountain pass he planned to fly through was obscured, and he intended to climb over the mountains and descend through holes in the clouds as he neared the destination. Radar data also indicated that the airplane operated above 12,500 ft mean sea level (msl) for about 30 minutes, and above 14,000 msl for an additional 14 minutes before entering a gradual descent during the last approximate 20 minutes of flight. Review of weather information indicated that cloud layers over the accident area increased during the 30 minutes before the accident, and it is likely that the airplane was operating in icing conditions, although it was not certified for flight in such conditions, which may have resulted in structural or induction icing and an uncontrolled loss of altitude. The airplane wreckage came to rest on the steep face of a snow-covered mountain in a slight nose-down, level attitude. The empennage was intact, the right wing was completely separated, and the forward fuselage and cockpit were partially separated and displaced from the airframe with significant crush damage, indicative of impact with terrain during forward flight. Page 2 of 10 ANC17FA004 There was no indication that the airplane was equipped with supplemental oxygen; pilots are required to use oxygen when operating at altitudes above 12,500 ft for more than 30 minutes, and anytime at altitudes above 14,000 ft. It could not be determined if, or to what extent, the pilot may have experienced symptoms of hypoxia that would have affected his decision-making. The airplane wreckage was not recovered or examined due to hazardous terrain and environmental conditions, and the reason for the impact with terrain could not be determined; however, it is likely that deteriorating enroute weather and icing conditions contributed to the outcome of the accident.

The pilot reported that the purpose of the flight was to reposition the airplane to another airport for refuel. During preflight, he reported that the airplane's two fuel gauges read "low," but the supplemental electronic fuel totalizer displayed 55 total gallons. He further reported that it is not feasible to visual check the fuel quantity, because the fueling ports are located near the wingtips and the fuel quantity cannot be measured with any "external measuring device." According to the pilot, his planned flight was 20 minutes and the fuel quantity, as indicated by the fuel totalizer, was sufficient. The pilot reported that about 12 nautical miles from the destination airport, both engines began to "surge" and subsequently lost power. During the forced landing, the pilot deviated to land in grass between a highway, the airplane touched down hard, and the landing gear collapsed. The fuselage and both wings sustained substantial damage. The pilot reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. The pilot reported in the National Transportation Safety Board Pilot/ Operator Aircraft Accident Report that there was a "disparity" between the actual fuel quantity and the fuel quantity set in the electronic fuel totalizer. He further reported that a few days before the accident, he set the total fuel totalizer quantity to full after refueling, but in hindsight, he did not believe the fuel tanks were actually full because the wings may not have been level during the fueling. The "Preflight" chapter within the operating manual for the fuel totalizer in part states: "Digiflo-L is a fuel flow measuring system and NOT a quantity-sensing device. A visual inspection and positive determination of the usable fuel in the fuel tanks is a necessity. Therefore, it is imperative that the determined available usable fuel be manually entered into the system."

On 10 October 2016, at approximately 0820 Pacific Daylight Time, a privately operated de Havilland DHC-2 Beaver aircraft on amphibious floats (registration C-GEWG, serial number 842), departed from Vanderhoof Airport, British Columbia, for a day visual flight rules flight to Laidman Lake, British Columbia. The pilot and 4 passengers were on board. Approximately 24 minutes into the flight, the aircraft struck terrain about 11 nautical miles east of Laidman Lake. The 406 MHz emergency locator transmitter (ELT) activated on impact. The ELT's distress signal was detected by the Cospas-Sarsat satellite system, and a search-and-rescue operation was initiated by the Joint Rescue Coordination Centre Victoria. One of the passengers was able to call 911 using a cell phone. The pilot was fatally injured, and 2 passengers were seriously injured. The other 2 passengers sustained minor injuries. The aircraft was substantially damaged. There was no post-impact fire.

The single engine aircraft was completing a charter flight from Trujillo to Pucallpa, carrying two pilots and pilot. While cruising over the Cajamarca Province, the pilot encountered poor weather conditions with heavy rain falls. He modified his route and was able to continue under VFR mode in good weather conditions. Nevertheless, he continued at an insufficient altitude when the aircraft impacted ground and crashed in a mountainous area. The aircraft was destroyed by impact forces and all three occupants were killed. There was no fire.

On October 2, 2016, about 1157 Alaska daylight time, Ravn Connect flight 3153, a turbine powered Cessna 208B Grand Caravan airplane, N208SD, collided with steep, mountainous terrain about 10 nautical miles northwest of Togiak Airport (PATG), Togiak, Alaska. The two commercial pilots and the passenger were killed, and the airplane was destroyed. The scheduled commuter flight was operated under visual flight rules by Hageland Aviation Services, Inc., Anchorage, Alaska, under the provisions of Title 14 Code of Federal Regulations Part 135. Visual meteorological conditions prevailed at PATG (which had the closest weather observing station to the accident site), but a second company flight crew (whose flight departed about 2 minutes after the accident airplane and initially followed a similar route) reported that they observed unexpected fog, changing clouds, and the potential for rain along the accident route. Company flight-following procedures were in effect. The flight departed Quinhagak Airport, Quinhagak, Alaska, about 1133 and was en route to PATG.

The noninstrument-rated private pilot was conducting a visual flight rules (VFR) cross-country flight while receiving VFR flight following services from air traffic control. Radar data and voice
communication information indicated that the airplane was in cruise flight as the pilot deviated around convective weather near his destination. The controller issued a weather advisory to the pilot concerning areas of moderate to extreme precipitation along his route; the pilot responded that he saw the weather on the airplane's NEXRAD weather display system and planned to deviate around it before resuming course. About 3 minutes later, the pilot stated that he was around the weather and requested to start his descent direct toward his destination. The controller advised the pilot to descend at his discretion. Radar showed the airplane in a descending right turn before radar contact was lost at 2,900 ft mean sea level. There were no eyewitnesses, and search personnel reported rain and thunderstorms in the area about the time of the accident. The distribution of the wreckage was consistent with an in-flight breakup. Examination of the airframe revealed overload failures of the empennage and wings. No pre-impact airframe structural anomalies were found, and the propeller showed evidence of rotation at the time of impact. Further, there was no evidence of pilot impairment or incapacitation. Review of weather information indicated that the pilot most likely encountered instrument meteorological conditions as the airplane descended during the last several minutes of flight. During this time, it is likely that the pilot became disoriented while attempting to maneuver in convective, restricted visibility conditions, and lost control of the airplane. The transition from visual to instrument flight conditions would have been conducive to the development of spatial disorientation; the turning descent before the loss of radar contact and the in-flight breakup are also consistent with a loss of control due to spatial disorientation.

The twin engine airplane was completing a flight to Asunción, carrying one passenger and one pilot. En route, the pilot encountered an unexpected situation and was forced to attempt an emergency landing. Upon landing on a dirt road, the aircraft lost its undercarriage and slid for few dozen metres before coming to rest with its right wing torn off. Both occupants were injured and the aircraft was destroyed.

The Cessna had departed about 3 minutes prior on a scheduled passenger flight and the Piper was en route to a remote hunting camp when the two airplanes collided at an altitude about 1,760 ft mean sea level over a remote area in day, visual meteorological conditions. The airline transport pilot and two passengers onboard the Cessna and the commercial pilot and the passenger onboard the Piper were fatally injured; both airplanes were destroyed. Post accident examination revealed signatures consistent with the Cessna's outboard left wing initially impacting the Piper's right wing forward strut while in level cruise flight. Examination revealed no mechanical malfunctions or anomalies that would have precluded normal operation of either airplane. Neither pilot was in communication with an air traffic control facility and they were not required to be. A performance and visibility study indicated that each airplane would have remained a relatively small, slow-moving object in the other pilot's window (their fuselages spanning less than 0.5° of the field of view, equivalent to the diameter of a penny viewed from about 7 ft away) until about 10 seconds before the collision, at which time it would have appeared to grow in size suddenly (the "blossom" effect). From about 2 minutes before the collision, neither airplane would have been obscured from the other airplane pilot's (nominal) field of view by cockpit structure, although the Cessna would have appeared close to the bottom of the Piper's right wing and near the forward edge of its forward wing strut. The Cessna was Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipped; the Piper was not ADS-B equipped, and neither airplane was equipped with any cockpit display of traffic information (CDTI). CDTI data would have presented visual information regarding the potential conflict to both pilots beginning about 2 minutes 39 seconds and auditory information beginning about 39 seconds before the collision, providing adequate time for the pilots to react. The see-and-avoid concept requires a pilot to look through the cockpit windows, identify other aircraft, decide if any aircraft are collision threats, and, if necessary, take the appropriate action to avert a collision. There are inherent limitations of this concept, including limitations of the human visual and information processing systems, pilot tasks that compete with the requirement to scan for traffic, the limited field of view from the cockpit, and environmental factors that could diminish the visibility of other aircraft. Given the remote area in which the airplanes were operating, it is likely that the pilots had relaxed their vigilance in looking for traffic. The circumstances of this accident underscore the difficultly in seeing airborne traffic by pilots; the foundation of the "see and avoid" concept in VMC, even when the cockpit visibility offers opportunities to do so, and particularly when the pilots have no warning of traffic in the vicinity. Due to the level of trauma sustained to the Cessna pilot, the autopsy was inconclusive for the presence of natural disease. It was undetermined if natural disease could have presented a significant hazard to flight safety.

The crew was performing a cargo flight from La Paragua to Canaima. While descending to Canaima in the early morning, the crew encountered an unexpected situation and was forced to attempt an emergency landing. The airplane crashed some 34 km northeast of the intended destination, bursting into flames. The aircraft was destroyed by a post crash fire and both occupants were killed.
Crew:
Johnny Ramirez, pilot,
José Angel Soto Zapata, copilot.