Cargo

The aircraft departed Ekimchan on a flight to Chumikan with an intermediate stop in Udskoye, carrying two pilots, one passenger and a load of food. Eight minutes after takeoff, while flying in poor weather conditions, the single engine aircraft struck the slope of Mt Bryus (1,767 metres high) located in the Selemja Mountain Range, some 19 km east of Ekimchan. The wreckage was found 12 days later, at an altitude of 1,560 metres. All three occupants were killed.

The small, twin-engine business jet was about 15 feet above the runway on takeoff, when a flock of birds from both sides of the runway flew up in front of the airplane. The number two engine "surged," and "loud reports" were heard before the copilot noted a complete loss of power on the number two engine instruments. The airplane climbed for about 10 seconds, before the copilot observed the gas producer (N1) gauge on the number one engine decay through 50 percent. The stall warning horn sounded, and the pilot adjusted the flight controls for landing. The airplane contacted the runway with the landing gear retracted, overran the runway, struck a fence, crossed a road, and came to rest in a cornfield about 1,000 feet beyond the initial point of ground contact. Post accident examination of both engines revealed evidence and damage consistent with multiple bird ingestion.

The commercial pilot was executing a precision instrument approach at night in instrument meteorological conditions when the airplane collided with terrain about four miles short of the runway. A review of air traffic control communications and radar data revealed the pilot was vectored onto the final approach course but never got established on the glide slope. Instead, he made a controlled descent below the glide slope as he proceeded toward the airport. When the airplane was five miles from the airport, a tower controller received an aural low altitude alert generated by the Minimum Safe Altitude Warning (MSAW) system. The tower controller immediately notified the pilot of his low altitude, but the airplane collided with terrain within seconds. Examination of the instrument approach system and onboard flight navigation equipment revealed no pre-mishap anomalies. A review of the MSAW adaptation parameters revealed that the tower controller would only have received an aural alarm for aircraft operating within 5 nm of the airport. However, the frequency change from the approach controller to the tower controller occurred when the airplane was about 10.7 miles from the airport, leaving a 5.7 mile segment where both controllers could receive visual alerts, but only the approach controller received an aural alarm. A tower controller does not utilize a radar display as a primary resource for managing air traffic. In 2004, the FAA changed a policy, which eliminated an approach controller's responsibility to inform a tower controller of a low altitude alert if the tower had MSAW capability. The approach controller thought the MSAW alarm parameter was set 10 miles from the airport, and not the 5 miles that existed at the time of the accident. Subsequent investigation revealed, that The FAA had improperly informed controllers to ensure they understood the alarm parameters for control towers in their area of responsibility. This led the approach controller to conclude that the airplane was no longer her responsibility once she handed it over to the tower controller. Plus, the tone of the approach controller's aural MSAW alarm was not sufficient in properly alerting her of the low altitude alert.

The airplane impacted a road and scrub brush during a forced landing, which was preceded by a total loss of engine power. According to the pilot, he heard a loud "thunk" during takeoff climb and noted a loss of engine power. He manipulated the power lever from the full forward position to the full aft position ("stop-to-stop") and noted he had no power. Post-accident examination of the Pratt & Whitney Canada PT6A -114A engine revealed that the compressor turbine (CT) vane's outer rim liberated a section of metal that damaged the turbine blades downstream. The area of liberated material from the CT vane outer rim was examined by the manufacturer's metallurgists. The fracture surface of the outer rim showed evidence of fatigue with signs of oxidation in some areas indicating the crack had been in existence for some time. The liberated material impact damaged the CT blades and resulted in a loss of power. Review of the operator's records revealed that the engine was approved for an extension beyond the normally recommended 3,600-hour overhaul period, to 5,100 hours. The engine had accumulated 4,461.3 hours at the time of the accident. In addition, the turbine section (hot section) had a recommended overhaul period of 1,800 hours; however, the operator instead elected to utilize an engine trend monitoring program in accordance with a manufacturer issued service bulletin. Many errors were noted with the operator's manually recorded data utilized for the trend monitoring. However, it is not likely that the engine trend data, even had it been correctly recorded and monitored, would have depicted the fatigue cracking in the CT vane outer rim. As a result, the manufacturer issued a service information letter (SIL) PT6A116 in January 27, 2003 (following a similar investigation), which reminded operators to conduct borescope inspections of the CT vane during routine fuel nozzle maintenance, as the manufacturer's maintenance manual recommended. Review of the maintenance record entries for the accident engine revealed no evidence that a borescope inspection had been conducted in conjunction with the fuel nozzle checks.

After takeoff from Kapoeta Airport, one of the engine failed. The crew elected to return but eventually made an emergency landing near the airport. There were no injuries and the aircraft was damaged beyond repair. The exact date of the mishap remains unknown, somewhere in June 2005.

During the takeoff roll at Kongolo Airport, the left main gear collided with an unidentified object. After takeoff, the crew was unable to raise the landing gear and decided to continue to Goma in such configuration. Upon touchdown at Goma Airport, the left main gear collapsed. The aircraft veered off runway to the left and came to rest. All nine occupants escaped uninjured while the aircraft was damaged beyond repair.

The 1,608-hour commercial pilot departed on a scheduled cargo flight. Prior to departure, he performed a preflight inspection and visually verified all five fuel tanks were full. The flight took approximately 1 hour for the 162 nautical mile cross-country flight. Prior to his return flight, he again checked the fuel and oil. He noted that, he had 3 hours of fuel on board. About 15 minutes after departure, the pilot switched to the auxiliary tanks. The pilot stated, "after 10-15 minutes on taking fuel from the auxiliary tanks, I switched to the right locker tank." Shortly thereafter, air traffic control instructed him to start a descent, and he selected the main fuel tanks. During the approach, the right engine began to "sputter". As the pilot was going through the engine failure checklist, the left engine "started sputtering." The pilot switched the auxiliary fuel pumps to high; then changed from the main tanks to the auxiliary fuel tanks. The airplane landed short of runway 12R. Inspection of the aircraft revealed, both auxiliary fuel tanks were "dry", the right main fuel tank contained approximately 3-inches of fuel, and the left main tank was "dry", but had been breached during the landing. The right wing locker fuel tank was full of fuel, and the transfer switch was in the off position. The left fuel selector was found in the left auxiliary position and the right fuel selector was found in the right auxiliary position. The main fuel line on the right engine had no fuel in it, and the line to the fuel manifold valve was empty as well. The left main fuel line had a "couple teaspoons" of fuel in it, and the fuel line to the left fuel manifold valve was absent of fuel.

Following a night approach to Addis Ababa-Bole Airport, the aircraft landed hard and bounced several times. It lost its undercarriage, slid for few dozen metres then veered off runway to the left and came to rest. All five crew members escaped uninjured while the aircraft was damaged beyond repair.

The crew stated the airplane was hire by a private individual and had 220 gallons of fuel onboard, and was carrying 6 pieces of granite, weighing 3,200 lbs. The passenger was responsible for the granite during the flight. During takeoff, about 400 feet above the ground, a discrepancy with the left engine manifold pressure was noted, followed by a slight hesitation and mild backfire. Oil was seen leaking from the front nose section of the engine followed by an engine manifold pressure and rpm decrease. Smoke coming from the left engine was observed and reported by the airport controllers. The left engine's propeller failed to feather and the airplane wouldn't maintain altitude. The airplane impacted trees, vehicles, and the right wing struck a home before coming to a stop on the road. A fire ensued immediately after ground impact, all onboard exited without assistance. The fuselage from the cockpit to the tail section melted from the fire. The right wing was damaged by impact and fire, and the right engine remained intact on the wing. The left wing was separated 12 feet from the outboard and the engine separated from the firewall. Both engine's propellers were in the low pitch position. The flaps were full up and the landing gear were retracted. A weight and balance sheet was never furnished. The pieces of granite and limited cargo recovered from the wreckage weighed 3,140 lb. Examination of the airplane revealed all flight controls surface were present and flight control continuity was accounted for and established. No evidence of any pre-impact mechanical discrepancies with the airframe or its systems was found that wound have prevented normal operation of airplane. On December 09, 2004, the left engine's nose section assembly was found with six out of the ten retaining bolts broken. The section was inspected and all ten bolts were replaced with serviceable ones. The assembly of the dose dome section and installation to the engine was performed by the repair station mechanic. The remaining assembling of the engine was completed by the operator's mechanic/pilot. During the left engine post accident examination, the ten bolts securing the nose dome section flange to the stationary reduction gear were fractured with their respective safety wire still intact. The chamber for the propeller feathering oil system was not secured to the plate sections, producing a bypass of the oil for the propeller feathering process. Metal flakes and pieces were observed deposited in the oil breather screen, consistent with the master rod bearing in an advance stage of deterioration. The silver plated master rod bearing had a catastrophic failure. Silver like metal flakes and particles were observed throughout the nose section, reduction gear section, main oil screen, and oil filter housing of the engine. An indication of propeller shaft housing movement was evident. Metal flakes with carbon build up were observed in the propeller shaft support and sleeve assembly. A metallurgical examination of the ten bolts securing the nose dome assembly indicated all were fractured though the threaded section of the shanks. The fatigue zones propagated from the opposite sides toward the center of the bolts consistent with reversed bending of the bolt.

The twin engine aircraft departed Kisangani-Bangoka Airport at 1248LT on a cargo flight to Isiro, carrying seven passengers, four crew members and a load of soap. About half an hour into the flight, the crew informed ATC about technical problems and elected to return. While descending to Kisangani, the aircraft crashed in a wooded area located 28 km north of the airfield, bursting into flames. A passenger was seriously injured while 10 other occupants were killed.