Mountains

The evening prior to the accident, the pilot acquired a computer generated text weather briefing. On the day of the accident, the pilot acquired another computer generated text weather briefing, and then contacted the Flight Service Station (FSS) for an interactive telephonic weather briefing. The information provided in all three briefings indicated that a flight on a direct route between the pilot's point of departure and his planned destination would take him through an area of forecast rain showers, thunderstorms, and cloud tops significantly higher than his intended en route altitude. Although the FSS briefer recommended an alternate route, for which he provided weather information, after departure the pilot flew directly toward his destination airport. While en route, the pilot, who was not instrument rated, encountered instrument meteorological conditions, within which there was an 80 percent probability of icing. After entering the area of instrument meteorological conditions, the airplane was seen exiting the bottom of an overcast cloud layer with a significant portion of its left wing missing. It then made a high velocity steep descent into the terrain. A postaccident inspection of the airplane's structure did not find any evidence of an anomaly that would contribute to the separation of the wing structure, and it is most likely that the wing section separated as a result of the airplane exceeding its structural limitations after the pilot lost control in the instrument meteorological conditions.

On August 9, 2010, about 1442 Alaska daylight time, a single-engine, turbine-powered, amphibious float-equipped de Havilland DHC-3T airplane, N455A, impacted mountainous, tree-covered terrain about 10 nautical miles (nm) northeast of Aleknagik, Alaska. The airline transport pilot and four passengers received fatal injuries, and four passengers received serious injuries. The airplane sustained substantial damage, including deformation and breaching of the fuselage. The flight was operated by GCI Communication Corp. (GCI), of Anchorage, Alaska, under the provisions of 14 Code of Federal Regulations (CFR) Part 91. About the time of the accident, meteorological conditions that met the criteria for marginal visual flight rules (MVFR) were reported at Dillingham Airport (DLG), Dillingham, Alaska, about 18 nm south of the accident site. No flight plan was filed. The flight departed about 1427 from a GCI-owned private lodge on the shore of Lake Nerka and was en route to a remote sport fishing camp about 52 nm southeast on the Nushagak River. According to GCI lodge personnel, the purpose of the flight was to transport the lodge guests to the fishing camp for an afternoon of fishing. The GCI lodge manager stated that the accident pilot had flown previously that morning in the accident airplane to DLG, where he dropped off another GCI pilot and then returned to the lodge. Sky Connect tracking system data for the accident airplane showed that, on that previous trip, the accident pilot departed the lodge for DLG about 0902 and returned about 1120. A review of DLG flight service station (FSS) recordings revealed that, about 1105, during the return flight from DLG to the lodge, the accident pilot filed a pilot report (PIREP) in which he reported ceilings at 500 feet, visibility of 2 to 3 miles in light rain, and “extremely irritating…continuous light chop” turbulence that he described as “kind of that shove-around type stuff rather than just bumps.” According to GCI lodge personnel, when the pilot returned to the lodge, he stated that the weather was not conducive for a flight to the fishing camp because of the turbulence and low ceilings. Passengers from the accident flight and GCI personnel indicated during postaccident interviews that, by the time that they had lunch about 1300, the weather had improved, and the group discussed with the pilot the option of going to the fishing camp. One passenger characterized the conversation as casual and stated that no pressure was placed on the pilot to make the flight or to depart by a certain time. The GCI lodge manager and some passengers stated that they thought that the pilot checked the weather on the computer during lunch, and the guest party co-host (one of GCI’s senior vice presidents) stated that the pilot informed him about 1400 that he was comfortable taking the group to the fishing camp if the group wanted to go. The GCI lodge manager stated that, before the airplane departed, he sent an e-mail to the fishing camp to indicate that the guests were coming, and personnel there informed him that the pilot had already contacted them. The lodge manager stated that he went down to the dock to help push the airplane off and that, when the flight departed, he could see all of Jackknife Mountain across the lake. (The mountain’s highest peak, which is about 3 nm from the dock, is depicted as 2,326 feet above mean sea level [msl] on an aviation sectional chart, and the elevation of Lake Nerka is depicted as about 40 feet msl on a topographical map.) He stated that the weather included broken ceilings about 2,000 feet above ground level (agl) with some blue patches in the sky and good visibility. The flight route from the lodge to the fishing camp traversed Class G airspace; 14 CFR 91.155 specifies that, for daytime flights below 1,200 feet agl, the flight must be flown clear of clouds and in conditions that allow at least 1 mile flight visibility. During a postaccident interview, the passenger who was in the right cockpit seat stated that, when the airplane departed, the visibility was “fine.” He stated that the pilot went a different direction during takeoff (compared to the passenger’s experiences during previous flights to the fishing camp) and that the pilot said it was to avoid “wind and weather.” The passenger described the weather as cloudy above with light turbulence. He stated that the airplane stayed below the clouds and that he noticed water “running across” the outside of the windshield before he fell asleep about 10 minutes into the flight. Another passenger, who was seated in the second seat behind the pilot on the left side of the airplane, stated that some fog was present beneath the airplane but that he did not think that the airplane flew into any clouds. He estimated that he fell asleep about 3 to 4 minutes after departure. The passenger who was in the first seat behind the pilot on the left side of the airplane stated in an initial interview that he could not see well out his side window and that he had no indication of the weather; however, in a subsequent interview, he stated that, once the airplane was airborne, he could not see the ground and could see only “white-out” conditions outside the airplane. He stated in the subsequent interview that he did not know if the airplane had climbed into clouds initially or if it had entered clouds at some point along the way. The passenger who was in the third seat behind the pilot on the left side of the airplane stated that the pilot kept the airplane below the cloud ceiling and flew along the tree line, followed streams, and maneuvered to avoid terrain. The passenger stated that the airplane banked into a left turn (he said that the bank angle was not unusual) and then immediately impacted terrain. Neither he nor the other passenger who was awake at the time of impact recalled noticing any unusual maneuvering, unusual bank or pitch angles, or change in engine noises that would indicate any problem before the airplane impacted terrain. The wreckage was found at an elevation of about 950 feet msl in steep, wooded terrain in the Muklung Hills, about 16 nm southeast of the GCI lodge. Figure 1 shows the accident site (view looking north-northwest).

The pilot, co-pilot and the passenger departed on a day VFR cross country flight in a large, 1950's era former military transportb category airplane to deliver cargo. The pilot did not file a flight plan, and had no communication with any air traffic control facility during the flight. While en route, witnesses saw the airplane fly slowly across a valley near the entrance of a national park, which was not the intended route of flight. The airplane suddenly pitched up, stalled, and dived into wooded terrain within the park. Two pilot-rated witnesses said the engines were operating at the time of the accident, and the landing gear was retracted. An on-scene examination of the burned airplane structure and engines revealed no evidence of any preaccident mechanical deficiencies, or any evidence that the cargo had shifted during the flight. A former military pilot who had experience in the accident type airplane, stated that the airplane was considered unrecoverable from a stall, and for that reason, pilots did not typically practice stalls in it. He also indicated that if a problem was encountered with one of the two piston engines on the airplane, the auxiliary jet engine on the affected side should be started to provide additional thrust. Given the lack of mechanical deficiencies discovered during postaccident inspection, the absence of any distress communications, and the fact that neither of the two auxiliary jet engines had been started to assist in the event of a piston engine malfunction, it is likely the pilot allowed the airplane to lose airspeed and enter a low altitude stall from which he was unable to recover.

Crew was fighting a forest fire near Siwash Road, about 15 km south of Lytton. The bombing run required crossing the edge of a ravine in the side of the Fraser River canyon before descending on the fire located in the ravine. About 22 minutes after departure, Tanker 448 approached the ravine and struck trees. An unanticipated retardant drop occurred coincident with the tree strikes. Seconds later, Tanker 448 entered a left-hand spin and collided with terrain. A post-impact explosion and fire consumed much of the wreckage. A signal was not received from the on-board emergency locator transmitter; nor was it recovered. Both crew members were fatally injured.

Flight ABQ202, operated by Airblue, was scheduled to fly a domestic flight sector Karachi - Islamabad. The aircraft had 152 persons on board, including six crew members. The Captain of aircraft was Captain Pervez Iqbal Chaudhary. Mishap aircraft took-off from Karachi at 0241 UTC (0741 PST) for Islamabad. At time 0441:08, while executing a circling approach for RWY-12 at Islamabad, it flew into Margalla Hills, and crashed at a distance of 9.6 NM, on a radial 334 from Islamabad VOR. The aircraft was completely destroyed and all souls on board the aircraft, sustained fatal injuries.

The float-equipped de Havilland Beaver DHC-2 Mk.I (registration number C-GAXL, serial number 1032), operated by Air Saguenay (1980) Inc., was flying under visual flight rules from Lac des Quatre to Lac Margane, Quebec, with 1 pilot and 5 passengers on board. A few minutes after take-off, the pilot reported intentions of making a precautionary landing due to adverse weather conditions. At approximately 1117, Eastern Daylight Time, the aircraft hit a mountain, 12 nautical miles west-south-west of the southern part of Lac Péribonka. The aircraft was destroyed and partly consumed by the fire that broke out after the impact. The pilot and 3 passengers were killed; 1 passenger sustained serious injuries and 1 passenger sustained minor injuries. No ELT signal was received.

The twin engine airplane departed Valle de la Pascua Airport at 0646LT on a flight to La Carlota-General Francisco de Miranda Air Base. At 0722LT, the crew reported his position at 7,000 feet when contact was lost. The wreckage was found the following day at 1700LT in a wooded and hilly terrain located between Mt Izcaragua and Mt Meregoto, about 18 km northeast of La Carlota Airport. The aircraft was destroyed and all three occupants were killed.

Aircraft departed on a round trip flight from Goose Bay to Cartwright and Black Tickle before returning to Goose Bay, Newfoundland and Labrador. The pilot was to deliver freight to Cartwright as well as a passenger and some freight to Black Tickle. At approximately 0905, the pilot made a radio broadcast advising that the aircraft was 60 nautical miles west of Cartwright. No further radio broadcasts were received. The aircraft did not arrive at destination and, at 1010, was reported as missing. The search for the aircraft was hampered by poor weather. On 28 May 2010, at about 2200, the aircraft wreckage was located on a plateau in the Mealy Mountains. Both occupants of the aircraft were fatally injured. The aircraft was destroyed by impact forces and a post-crash fire. There was no emergency locator transmitter on board and, as such, no signal was received.

The twin engine aircraft departed Kunduz Airport at 0900LT on a flight to Kabul, carrying 38 passengers and six crew members, among them six foreigners. En route, while flying in marginal weather conditions with limited visibility due to fog, the aircraft struck the slope of a mountain located south of the Salang Pass. The crew of an ISAF helicopter localized the wreckage 3 days later in a snow covered area at an altitude of 4,270 metres. The aircraft disintegrated on impact and all 44 occupants were killed.

During the early evening, at 1946 hrs, after a flight time of one hour and 50 minutes the airplane came back to Prague, Czech Republic, after a flight to France. For the Pilot in Command (PIC) it was the first flight of the day. The co-pilot left the airplane after the landing and was replaced by the copilot of the subsequent accident flight. The co-pilot had already flown two flights that day - around midday - with a total flight time of one hour and 40 minutes. There were no passengers on board. The aircraft departed Prague at 2008 hrs for a ferry flight to Karlskrona, Sweden. The flight was conducted in accordance with Instrument Flight Rules (IFR). The course of events is described based on the analysis of the recordings of the Flight Data Recorder (FDR), the Cockpit Voice Recorder (CVR), radar and radio communications. The appendix shows two different FDR recording diagrams. Diagram 1 shows the entire flight (time in UTC) and diagram 2 shows the flight from 1918:30 UTC on. Take-off took place on runway 31. The co-pilot was Pilot Flying (PF). The flight was conducted manually, neither of the two autopilots was engaged. From 2012 hrs on, after a right hand turn, the flight proceeded toward the north. The airplane was in climb attitude. At 2014:16 hrs, still in climb, the PIC said "I didn't fly night time for long time". The co-pilot asked: "Have you already experienced a roll during night?" She answered laughing: "Yes, really." He: "Better we won't." She laughing: "Do you enjoy that thing?" Co-pilot: "You are the first one with whom I talked about it, don't tell it [...]." PIC: "Whom shall I not tell?" [...] She again: "I also do it always, but I persuade [...] to do that." Co-pilot: "[...] Bravo does it better." At 2015:00 hrs, during this short conversation, the crew received the instruction from ATC Prague to climb to FL260 and to level off above reporting point DEKOV. The conversation in the cockpit continued. Co-pilot: "Bravo does the roll faster with the ailerons but the spoilers are slower." At 2015:33 hrs ATC repeated the instruction. At 2015:40 hrs the PIC acknowledged the instruction. Between 2017:10 hrs and 2017:20 hrs the airplane rolled about its longitudinal axis; initially to the left up to a bank angle of 30°, and right afterwards to the right up to a bank angle of 20°, then back again to the horizontal. At 2017:20 hrs the PIC responded to it with the words: "Let's go, we are already high enough, you nettle me - come on [...]." At 2017:22rs ATC Prague instructed the crew to contact ATC Munich; at 2017:35 hrs the PIC confirmed the instruction. At 2017:42 hrs she said: "Later but." The co-pilot replied: "Let's do it at higher altitude." At 2018:29 hrs, the PIC contacted ATC Munich. At 2018:36 hrs the crew received the instruction from ATC Munich to climb to FL330. This was confirmed at 2018:44 hrs. Between 2018:51 hrs and 2019:00 hrs the following conversation took place:
- 2018:51 hrs PIC: "Sufficient, is it sufficient?"
- 2018:53 hrs Co-pilot: "For what?"
- 2018:54 hrs PIC: "Sufficient."
- 2018:56 hrs PIC: "The altitude."
- 2018:58 hrs Co-pilot: "For what?"
- 2018:58 hrs PIC: "For that,"
- 2019:00 hrs Co-pilot: "It is sufficient."
At 2019:00 hrs the airplane levelled off in FL270, at 2019:05 hrs the airplane nose moved upward until a pitch angle of about 14° was reached. At 2019:09 hrs the aircraft began to roll about its longitudinal axis to the right. Within 4 seconds the airplane reached the inverted flight attitude and in another 4 seconds it rolled another 90°. Simultaneously the heading changed right toward the east, then toward the south and finally toward the west. During the roll the pitch angle decreased to almost -85° which is almost a vertical nose dive. The computed airspeed increased
significantly. The airplane crashed near Reinhardtsdorf-Schöna, Saxon Switzerland, about 500 m north of the border to the Czech Republic.