Mountains

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 single engine aircraft departed Medellín-Enrique Olaya Herrera Airport on a charter flight to Juradó, carrying nine passengers and two pilots. Shortly after takeoff, the crew encountered difficulties to gain sufficient altitude and apparently attempted an emergency landing when the aircraft impacted a hill and eventually crashed into trees. The copilot and three passengers were killed and seven others occupants were injured, some seriously. The aircraft was destroyed.

The single engine airplane was completing a positioning flight from Berdsk to Mansky where insecticides should be pulverized on wooded area. On board were a pilot, a mechanic and a passenger. Following a night in Berdsk, the airplane took off at 1201LT for the last leg to Mansky. En route, weather conditions deteriorated and the visibility was poor. Too low, the aircraft impacted trees and crashed in a wooded area located on the slope of Mt Abatova (747 metres high) located 40 km east of Krapivninsky. The airplane was destroyed by impact forces and a post crash fire. The wreckage was found the following day at an altitude of 541 metres. All three occupants were killed.
Crew:
R. Rodzhapov, pilot,
I. Valiullin, mechanic.
Passenger:
Yuri Pakhomov, maybe acting as a copilot on this flight, despite he was not licensed anymore.

The Beaver floatplane departed Telegraph Creek Water Aerodrome, BC (CAH9) destined for Mowdade Lake, BC, at approximately 2040 PDT on 15 July 2016 on a VFR flight itinerary round-trip with one pilot on board. When the aircraft did not arrive at Mowdade Lake and did not return to CAH9, a search was initiated. The aircraft's wreckage was located at approximately 2000 PDT the following day in a ravine at an elevation of about 5,000 feet near the headwaters of Elwyn Creek, BC. The aircraft was consumed by fire and the pilot was fatally injured.

During cruise flight through an area of mountainous terrain, the commercial pilot became geographically disoriented and selected the incorrect route through the mountains. Upon realizing it was the incorrect route, he initiated a steep climb while executing a 180° turn. During the steep climbing turn, the airplane inadvertently entered instrument meteorological conditions, and the airplane subsequently impacted an area of rocky, rising terrain. The pilot reported there were no mechanical malfunctions or anomalies that would have precluded normal operation of the airplane.

The aircraft departed Kanoya AFB at 1315LT on a calibration flight with six people on board. After he complete a counter clockwise arc, the crew started the descent to Kanoya AFB Runway 08R. The visibility was poor due to low clouds. On approach, at an altitude of 3,000 feet, the aircraft entered clouds when the GPWS alarm sounded. Two second later, the crew deactivated the alarm and continued the approach. Ten seconds later, the aircraft impacted trees and crashed on the slope of Mt Takakuma (1,182 metres high) located 10 km north of the airbase. The wreckage was found a day later and all six crew members were killed.

As per the flight plan submitted on 23rd February 2016, the aircraft was scheduled for VFR flight to Jomsom (VNJS) on 24th February with estimated off-block time of 01:00, intended cruising speed of 150 knots, intended level of 10,500 ft and via direct track. The first and second alternate aerodromes were Bhairahawa (VNBW) and Pokhara (VNPK) respectively and estimated elapsed time was 20 minutes with the fuel endurance of 2 hours and 30 minute. Based on the information from the CVR, FDR and ATC records, the following description of the history of the flight was reconstructed: At 01:55, the first-officer contacted Pokhara tower requesting Jomsom and Bhairahawa weather. Upon receiving Jomsom weather which was 8 km visibility towards Lete (arrival track) and foothill partially visible; at 01:56 F/O requested start-up for Jomsom. First-officer then briefed the weather to the captain, in response to this the captain responded by saying 'Let‘s have a look, if not possible we will return' (Translated from Nepali conversation). While performing the 'before start checklist', they received weather of Bhairahawa as closed. After completing the checklist and start-up the first-officer at 02:00 requested taxi clearance. The ATC informed runway change to 22 instead of runway 04 and gave taxi clearance. At 02:03 while taxiing the captain considering bad weather condition expressed his concern over the runway change with F/O but failed to express it to the ATC. As briefed by captain earlier, the control was transferred to F/O and at 02:04 F/O made a normal take-off. At 02:08 the captain reported 5 miles at 6,200 ft to ATC. At 02:09, while passing through 7,000 ft the captain informed the actual weather, which was light haze, mountain not visible but had ground contact, to an ultra-light aircraft upon his request. As per the cockpit conversation, the crew were comparing the base of the cloud which was higher than the day before and proposed to continue climb to 12,500 ft if not on-top of the cloud at 10,500 ft. Around 5 miles before Ghorepani passing 10,100 ft, the captain told that cells were still present so advised F/O to continue climb to 12,000 ft and told that they will proceed till TATOPANI and decide to continue or divert. At 02:14 approaching GHOREPANI and passing 11,400 ft, Captain told F/O to maintain level to be in between the cloud layers and briefed F/O that if they had to divert it would be a left turn. At the same time captain asked repeatedly to F/O if his side was raining for which F/O told and confirmed not visual, after which captain told they would see and decide (regarding continuation of flight). At 02:14:50 while over Ghorepani area at 11,500 ft the EGPWS TERRAIN alert and at 02:14:52 PULL UP warning came while they were not visual and at 02:15:01 it was stated that they were visual and by 02:14:53 the warning stopped. At 02:15 while maintaining 11,500 ft the captain reported ATC that they are at Ghorepani at level 10,500 ft after which frequency changeover to Jomsom tower was given. At 02:15:27 the captain instructed F/O to maintain heading of 3300 and flight level just below the cloud, after which a shallow descent was initiated. At this time captain asked F/O if his side was visual, in response F/O replied somewhat visual. The Captain then instructed F/O to descent to 10,000 ft. Once the descent was started at 02:15:55 passing 11,000 ft an OVERSPEED warning sounded in the cockpit for 2 seconds as the speed reached 152 knots. At 02:16 while passing 10,700 ft captain advised F/O to make a left turn so that it would be easy to turn if required as he was able to see his side. Then F/O asked if left side was visual for which the captain informed that not that side (towards the track) but somewhat visual to the left of him and told that the TRACK TO GO was TO THE LEFT whereas they were actually left of the track and had descended to 10,300 ft. At 02:17:58 EGPWS TERRAIN alert sounded when the aircraft was at 10,200 ft and descending on heading of 3210 with right bank angle of around 30 . At 02:18:06 when the aircraft had descended to 10,100 ft the PULL UP WARNING sounded for which the captain said not to worry and at 02:18:12; when the aircraft was at 10,000 ft the captain took-over the control, continued descent and asked F/O if his side was visual. The F/O informed that right side was not visual at all by which the aircraft had continued shallow descent on heading 3250 with right bank angle reaching up to 130 at 2:18:19 and by 02:18:23 the aircraft once again returned back to 0° bank angle. At 02:18:23 the captain started left bank followed by right bank again while still on a shallow descent until 02:18:27.Upon reaching 9,850 ft (lowest altitude) the aircraft started very shallow climb. At 02:18:35 when aircraft was 9,920 ft the captain told F/O that they reached Landslide (a checkpoint which is on track to Jomsom on the right side of the Kali-Gandaki River). At 02:18:44 when aircraft reached 10,150 ft captain told ―what I will do is now I will turn to heading of LETTE‖ (another way point on route to Jomsom); while the PULL-UP warning was continuously sounding. At 02:18:49 when the aircraft was at 10,300 ft right bank angle increased up to 16° with pitch up attitude of 7°. At 02:18:52 the captain told that he would start climb when the aircraft had reached 10,350 ft; pitch attitude of 10° and still on right bank. The aircraft reached zero degree bank at 02:18:53 and started shallow left bank with pitch attitude of 12° nose up. By 02:18:57 the bank angle reached 200 left with pitch attitude of 11.8 and altitude of 10,550 ft and captain was still questioning F/O about the visibility towards his side but F/O informed his side not visible completely. The last data recorded in FDR was at 02:19:03 when the altitude had reached around 10,700 ft; pitch attitude of 7° nose up and left bank angle of 25° heading of 335° with EGPWS PULL-UP warning ON.

The flight was uneventful until the start of the event, which occurred during the approach briefing in level flight at FL 330. The event started at 00:19:20 hrs during darkness without moonlight, clouds or turbulence. The lack of external visual references meant that the pilots were totally dependent on their instruments which, inter alia consisted of three independent attitude indicators. According to recorded data and simulations a very fast increase in pitch was displayed on the left attitude indicator. The pilot in command, who was the pilot flying and seated in the left seat exclaimed a strong expression. The displayed pitch change meant that the pilot in command was subjected to a surprise effect and a degradation of spatial orientation The autopilot was, most probably, disconnected automatically, a “cavalry charge” aural warning and a single chime was heard, the latter most likely as a result of miscompare between the left and right pilots’ flying displays (PFD). Both elevators moved towards nose down and nose down stabilizer trim was gradually activated from the left control wheel trim switch. The airplane started to descend, the angle of attack and G-loads became negative. Both pilots exclaimed strong expressions and the co-pilot said “come up”. About 13 seconds after the start of the event the crew were presented with two contradictory attitude indicators with red chevrons pointing in opposite directions. At the same time none of the instruments displayed any comparator caution due to the PFDs declutter function in unusual attitude. Bank angle warnings were heard and the maximum operating speed and Mach number were exceeded 17 seconds after the start of the event, which activated the overspeed warning. The speed continued to increase, a distress call was transmitted and acknowledged by the air traffic control and the engine thrust was reduced to flight idle. The crew was active during the entire event. The dialogue between the pilots consisted mainly of different perceptions regarding turn directions. They also expressed the need to climb. At this stage, the pilots were probably subjected to spatial disorientation. The aircraft collided with the ground one minute and twenty seconds after the initial height loss. The two pilots were fatally injured and the airplane was destroyed.

The twin engine aircraft departed Campo de Marte Airport at 1334LT on a positioning flight to Paraty, with an ETA at 1415LT. While descending to Paraty Airport, the crew encountered instrument meteorological conditions. On final, while approaching under VFR mode, the aircraft impacted trees and crashed in a dense wooded area located in hilly terrain few km short of runway. The aircraft was destroyed and both pilots were killed.

The airline transport pilot was conducting a scheduled passenger flight in an area of remote, snow-covered, mountainous terrain with seven passengers on board. The pilot reported that, after receiving a weather briefing, he chose to conduct the flight under visual flight rules (VFR). While en route about 10,000 ft mean sea level (msl), the visibility began "getting fuzzy." The pilot then descended the airplane to 2,500 ft msl (500 ft above ground level) to fly along a river. When the airplane was about 10 miles southwest of the airport, he climbed the airplane to about 3,000 ft msl in order to conduct a straight-in approach to the runway. He added that the visibility was again a little "fuzzy" due to snow and clouds, and that he never saw the airport. The pilot also noted that the flat light conditions limited his ability to determine his distance from the surrounding mountainous, snow-covered terrain. Shortly after climbing to 3,000 ft msl, the airplane collided with the rising terrain about 6 miles southwest of the airport. Another pilot, who had just departed from the airport, confirmed that flat light and low-visibility conditions existed in the area at the time of the accident. Further, camera images of the weather conditions recorded at the airport showed that, although conditions were marginal VFR at the surface at the time of the accident, there was mountain obscuration and reduced visibility due to light snow and clouds along the accident flight path and that the worst conditions were located along and near the higher terrain. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation. It is likely that that the pilot encountered flat light and low-visibility conditions as he neared the airport at 3,000 ft msl while operating under VFR and that he did not see the rising, snow-covered mountainous terrain and subsequently failed to maintain clearance from it.