Mountains

The pilot completed a flight without incident, and seemed in good spirits before departing, by himself, on the return flight. The second flight also progressed without a incident until cleared from 8,000 feet msl to 5,000 feet msl, which the pilot acknowledged. Visual meteorological conditions prevailed at the time, and radar data depicted the airplane initiate and maintain a 500-foot per-minute descent until radar contact was lost at approximately 400 feet agl. The pilot made no mention of difficulties while en route or during the descent. The airplane impacted trees at the top of a ridge in an approximate level attitude, and came to rest approximately 1,450 feet beyond, at the bottom of a ravine. Examination of the wreckage revealed no preimpact failures or malfunctions. The pilot had been diagnosed with Crohn's disease (a chronic recurrent gastrointestinal disease, with no clear surgical cure) for approximately 35 years, which required him to undergo several surgeries more than 20 years before the accident. The pilot received a letter from the FAA on June 11, 1998, stating he was eligible for a first-class medical certificate. In the letter there was no requirement for a follow up gastroenterological review, but the pilot was reminded he was prohibited from operating an aircraft if new symptoms or adverse changes occurred, or anytime medication was required. His condition seemed to be stable until approximately 5 months prior to the accident. During this time frame, he experienced weight loss and blood loss, was prescribed several different medications to include intravenous meperidine, received 3 units of blood, and had a peripherally inserted central catheter placed. On the pilot's airmen medical application dated the month prior to the accident, the pilot reported he did not currently use any medications, and did not note any changes to his health. A toxicological test conducted after the accident identified meperidine in the pilot's tissue.

The crew departed Roosevelt Roads NAS on a local training flight. In the evening, while returning the to NAS, the crew encountered poor weather conditions with low clouds, limited visibility and rain falls. While descending at low height, the crew suffered a loss of situational awareness and failed to respond to obstacle warnings. The four engine aircraft collided with trees and crashed on the top of Mt Perucho. The aircraft disintegrated on impact and all 10 crew members were killed.

The airplane was maneuvering to deliver fire retardant when its left wing separated. Aircraft control was lost and the airplane crashed into mountainous terrain. A witness on the ground took a series of photographs that showed the air tanker's left wing separating at the wing root and the remaining airplane entering a 45-degree dive to the ground in a counterclockwise roll. An examination of the airplane wreckage revealed extensive areas of preexisting fatigue in the left wing's forward spar lower spar cap, the adjacent spar web, and the adjacent area of the lower wing skin. The portion of the wing containing the fatigue crack was obscured by the retardant tanks and would not have been detectable by an exterior visual inspection. An examination of two other air tankers of the same make and model revealed the area where the failure occurred on the accident airplane was in a location masked by the airplane's fuselage construction. The airplane was manufactured in 1945 and was in military service until 1956. It was not designed with the intention of operating as a firefighting airplane. In 1958, the airplane was converted to civilian use as an airtanker and served in that capacity until the time of the accident. The investigation revealed that the owner developed service and inspection procedures for the airtanker; however, the information contained in the procedures did not adequately describe where and how to inspect for critical fatigue cracks. The procedures were based on U.S Navy PB4Y-2 airplane structural repair manuals that had not been revised since 1948.

The twin engine aircraft departed Jumla at 1404LT on a 25-minutes flight to Surkhet with two passengers and two pilots on board. While descending to Surkhet, the crew encountered poor visibility due to bad weather conditions. At an altitude of 6,500 feet, the aircraft struck the slope of a mountain and crashed 10 km from Surkhet. All four occupants were killed.

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 single engine aircraft departed Lake Cojibo with two passengers, one pilot and a full load of freight, destined for a fishing camp. Weather conditions were good but the OAT was high. After takeoff, the aircraft encountered difficulties to maintain a proper rate of climb due to the high temperature and the weight it was carrying. The pilot entered a valley and while trying to gain height to clear rising terrain, the aircraft struck the top of a mountain and crashed, bursting into flames. All three occupants were injured and the aircraft was destroyed by fire.

The aircraft was on a scheduled freight flight from Bloemfontein to George. Poor weather conditions prevailed over the George area and the pilots had to execute an instrument guided approach for the landing. The ground based Instrument Landing System (ILS) on Runway 29 at George Aerodrome was intermittently unreliable during the approach. The pilots decided to execute a missed approach. During the missed approach the pilots did not comply with the published missed approach procedure and with a combination of strong winds and possible erroneous heading indications they lost situational awareness. They flew the aircraft into a valley and crashed into the side of the mountains North-East of the George Aerodrome. The passenger was Hansie Cronje, a former South African cricket captain who had missed a South African Airlines flight.

While cruising in poor weather conditions at an altitude of 7,800 feet, the twin engine aircraft struck the slope of a mountain located about 50 km from Nabire. The aircraft was destroyed and all six occupants were killed. At the time of the accident, the visibility was poor due to heavy rain falls and the mountain struck by the aircraft was shrouded in mist.

The aircraft was cleared direct and to climb to 14,000 feet. During the climb out, the controller inquired several times as to the flights altitude. The pilot's response to the controllers queries were exactly 10,000 feet lower than what the controller was indicating on radar. Eventually the controller instructed the pilot to stop altitude squawk, which he did. During the last communication with the pilot, he reported that he was level at 14,000 feet. During the next approximately 45 minutes, the aircraft was observed proceeding generally in the direction of its destination. When the controller observed the flight track turn approximately 45 degrees to the right and headed generally northwest, he attempted to contact the pilot without a response. The tracking then turned about 90 degrees to the left for a few minutes, then turned 180 degrees to the right. The aircraft dropped from radar coverage shortly thereafter. On site investigation revealed that the aircraft broke-up in flight as the wreckage was scattered generally east-to-west over the mountainous terrain for approximately .3 nautical miles. Further investigation revealed that the right wing separated at the wing root in an upward direction. Separation points indicated features typical of overload. The right side horizontal stabilizer separated upward and aft. The left side horizontal stabilizer remained attached however, it was twisted down and aft. The aft fuselage was twisted to the left. Both engines separated in flight from the wings. Post-crash examinations of the airframe and engines did not reveal evidence of a mechanical failure or malfunction. Both altimeters were too badly damaged to test. Autopsy and toxicology results indicated that the pilot had severe coronary artery disease with greater than 95% narrowing of the left anterior descending coronary artery by atherosclerotic plaque. The coroner also reported that superimposed upon this severe narrowing was complete occlusion of the lumen by brown thrombus. Toxicology results indicated a moderate level of diabetes. The pilot's actions leading up to the accident were consistent with an incapacitation due to hypoxia. The role of a possible heart attack was unclear, since it is possible that it occurred as a result of the hypoxia.

The aircraft departed Budapest-Ferihegy Airport at 0829LT on a VFR flight to Tunis. According to the flight plan the aircraft would fly over Split, Pescara, crossing the Apennines towards Ostia and then onwards to Tunis. Weather conditions over the central part of Italy were poor with a cold front associated with thunderstorm activity, low clouds and icing conditions. After passing over the Adriatic sea, the aircraft overflew Pescara at 1320LT where the pilot informed ATC that the aircraft was inbound Aneda (a reporting point 19 NM East of Monte Rotondo) at a cruising altitude of 5.500 feet. While in vicinity of Pescara, ATC requested and obtained confirmation from the crew that he was able to continue under VFR mode. Shortly later, at a speed of 115 knots, the single engine aircraft struck the slope of Mt Rotondo (1.880 metres high) located near Rocca di Mezzo. The aircraft disintegrated on impact and all three occupants were killed.