Severe weather The
METAR in force at the time showed thunder showers and rain. Radar visuals on the weather at Kinshasa confirmed the presence of inclement conditions in the area at the time of the crash. The depicted squall line was described as severe and fast-moving with very low cloud base. Moving with a speed of from the northeast to the southwest, the system grew in size when it reached Kinshasa. The fast-moving nature of the weather system was the reason for the rapid visibility deterioration in Kinshasa, where in just 10 minutes the visibility had largely dropped from to just . A significant increase in wind speed was also noted. The weather system deepened and eventually grew in size. This was also confirmed by the cockpit recording in which First Officer Tsutkiridze expressed his shock at the large coverage of the weather system. Imagery from the area showed the colour "magenta", which indicated possible strong thunderstorm activity. Kinshasa's N'djili Airport was not provided with a weather radar, so the radar controller could not predict or relay information on the rapidly unfolding severe weather conditions to the crew of Flight 834. Despite this, Air Traffic Control (ATC) had warned the crew on the prevailing weather conditions at the airport with "Thunderstorm over the station", though the observance of squall line was not reported. However, the warning seems to have been ignored by the crew possibly due to the ATC personnel's slight accent. Due to the size of the storm, the crew had to go around it. As a result, the crew were unable to intercept the airport's localizer and to maintain their aircraft within the localizer path. They eventually managed to intercept the localizer at a distance of two nautical miles from the airport. The deteriorating visibility prompted the crew to execute a go-around but the squall line then produced microbursts with vertical gusts of up to . Data from the FDR corroborated this finding; vertical G fluctuations and yaw damper movements were recorded on the device.
Decision to land The onboard cockpit radar and the updated weather condition from the ATC had provided sufficient information to the crew regarding the weather conditions at their destination airport. The appropriate procedure to the presence of severe weather in the area around Kinshasa was to avoid attempting a landing. The crew, however, decided to continue their approach. There had been doubts cast by the crew on the weather depiction on their radar, but even when they realized that the weather had indeed deteriorated throughout Kinshasa, they kept hoping that the weather would improve. This was caused by the imagery on their radar, which showed the air mass moving away from the airport. The crew, believing that the airport would later be cleared of clouds, decided to continue their approach to Kinshasa. Their intention to land later became firmer as First Officer Tsutkiridze obtained visual contact with the runway, which was on the right side of the aircraft. He then asked Captain Hovhanesyan to turn the aircraft to the right, but the captain did not make such input, as he had not sighted the runway. The first officer then tried to convince the captain by pointing the direction of the runway and adding that "there was nothing there" (no significant weather phenomenon compared to the other area) and thus it was safer for them to fly there. Captain Hovhanesyan later saw the runway as well and prepared the aircraft for landing. Their decision to land, despite the adverse weather condition and their high airspeed, was described as inappropriate. According to the investigation, the crew might have had faced a "situation overload", which eventually decreased their ability to make decisions correctly.
Procedural deviations Other than the inappropriate decision that had been made by the crew, investigators also noted multiple procedural deviations during the entirety of the flight. Among those deviations were crew commencing their descent below 10,000 ft at a speed above normal, configuring the aircraft for a landing attempt at an altitude below the minimum descent altitude, no landing checklist callout, no reporting short on final as requested by ATC, continuing approach below minimum descent altitude during adverse weather conditions, non-adherence to weather avoidance procedure and numerous other procedural deviations. The crew had flown in the DRC for an extended period of time without any kind of supervision from Georgian Airways, MONUSCO, Georgian and DRC civil aviation administration regarding their flight conduct. Due to this lack of supervision, the crew believed that their deviations from flight manual would not be discovered by their supervisors. While Georgian Airways had adopted a Flight Operations Quality Assurance (FOQA) program, the airline had not followed said policy for the CRJ100 fleet. This lack of management supervision enabled the crew to deviate from the approved procedures.
Conduct of go-around As the crew decided to go around, the thrust was not increased to the required level. The nose attitude was not in a sufficiently upwards position for a recovery, being set at 8 degrees, and the aircraft's landing gear was not retracted. Due to the low altitude of the aircraft, according to investigators the crew would have needed a much more higher setting of the thrust lever (at fully forward position) and the landing gear should have been retracted for better aerodynamics. The nose pitch should have been raised to 10 degrees. As such, the crew would have had a better chance to recover from the microburst, albeit small. The analysis from the recordings raised questions on whether the pilots had pressed the
take-off go-around (TOGA) button during the go-around phase. This was due to the insufficient pitch attitude of the aircraft during the phase. The investigation noted that Captain Hovhanesyan, who was the pilot flying, had undergone simulator training only once for his upgrade to the CRJ100, which was deemed inadequate. He had recently been promoted to captain for the CRJ100 in December 2010. Prior to the captain's promotion, he had been flying as a first officer in a
Boeing 737 for several years. The location of the TOGA button in the Boeing 737 is very different from that of the CRJ100. On the Boeing 737, the button is located forward, adjacent to the thrust lever. To engage the TOGA button, the crew would push the button with the index finger. On the CRJ100, the button is located on the side of the throttle lever, so the crew would have to push it with the thumb sideways towards the lever. Due to lack of training, the captain possibly did not push the TOGA button with his thumb due to his habit with the previous aircraft type. By pressing the TOGA button, a command bar for the 10 degree reference indication would have appeared on the aircraft's flight director, and the pilots would have been able to notice it. Due to the non-activation of the TOGA, the reference 10 degree reference did not appear, and thus the pitch attitude was not raised. On the CRJ100, the command bar would have also appeared during the activation of the windshear warning. However, due to the low altitude and the strong force of the microburst, there were barely any time left for the crew to react.
Oversight failure The lack of simulator training that the captain received from Georgian Airways was attributed to the failure of the training program and oversight from the
Georgian Civil Aviation Administration (CAA). The syllabus from Georgian Airways had only required promoted pilots to undergo simulator training once before their respective line-oriented flight training. This was peculiar as, according to the investigation, such a practice was not used in other countries around the world. For a recently promoted captain, the norm in many airlines is to conduct 8 to 10 simulator trainings, particularly for the CRJ fleet. As a regulatory body for civil aviation in Georgia, the CAA should have reviewed the training program of Georgian Airways. The investigation stated that there were definite lapses in the oversight function of the CAA, as Georgian Airways was allowed to use such skimpy training. The CAA, however, insisted that such syllabus actually conformed to ICAO standards and as such stated that it could not be included as one of the contributing factors to the crash, although they admitted that more training in areas regarding severe weather conditions and "inadequate meteorological capabilities" were needed.
Other deficiencies Kinshasa's ATC personnel who was on duty at the time of the crash was also noted for deficiencies. The ATC kept referring the latest weather update as "NOSIG". The term NOSIG was an abbreviation from "no significant", implying that no significant weather change was observed on the radar for the next 30 minutes. During the accident flight, the weather rapidly deteriorated in mere minutes but the ATC personnel kept relaying the term NOSIG to the crew. The rapidly changing weather eventually caused the visibility over the airport to deteriorate. As the visibility dropped to below the minimum of 2,400 meters, the ATC personnel should have closed the airport. Had the airport been closed, Flight 834 would not have continued their approach to Kinshasa. The team from the CAA added that there were several other deficiencies from the ATC. According to the findings that had been gathered by the team, the crew had repeatedly tried to contact the ATC for the updated weather situation, but the ATC did not respond until a few minutes after the transmission. When contact was established between the ATC and the crew, the weather information was still not available. The updated weather report was eventually received by the crew, approximately one second before the crash. The ATC should have received the alert weather analysis from meteorological services and immediately contacted the crew on the weather conditions and also advised the crew on possible diversion. None of these actions were performed.
Final report An investigation from the Permanent Office of Investigations of Aviation Accidents/Incidents of the DRC
Ministry of Transport and Channels of Communication listed the probable cause of the accident as follow: A total of 13 recommendations were issued by the investigation team. Among the recommendations, the Congolese Ministry of Transport was asked to provide appropriate equipment for meteorological services in the DRC to provide better services. The DRC Civil Aviation Administration was ordered to immediately implement effective oversight on all airliners in the country and Georgian Airways was asked to revise their training program.
Differing view from Georgian counterpart Despite the findings that had been listed by the Congolese investigators, the Georgian CAA disputed several of the findings and asked clarifications on the content of the report. For instance, several statements were regarded as "devoid of objective analysis" pertinent to the situation and findings from Georgian CAA were included but not explained thoroughly, including the ATC's contributing factor to the crash. The go-around phase was particularly noted by the CAA. According to the report, the crew didn't carry out the approach of the flight in accordance with the approved procedure. The CAA, however, stated that such statement was misleading as it didn't fully reflect the analysis of the crew's action during the flight. As inclement weather condition was prevailing in Kinshasa at the time, the flight operation manual actually recommended the crew to maintain higher airspeed than normal. Due to the crew's decision to avoid the weather system in the area, the crew were forced to delay configuring their aircraft. The thrust setting that was applied by the crew at the time of the crash was just 1.8% lower than the recommended 92% thrust setting for a go-around procedure. This deviation was described as "insignificant", and, as the aircraft was struck by turbulence at the time, such precise setting of 92% thrust was deemed to be highly unlikely. Discussion with
Bombardier also revealed that, even though the thrust was lower than the recommended thrust setting and the extended position of the landing gear, the aircraft was still able to perform a successful go-around. The Congolese investigation team, however, assumed that higher thrust setting would have improved the pilots' chances of avoiding the accident. This was seen as irrelevant by the Georgian counterpart. The extended position of the landing gear and the non-activation of the TOGA button was also disputed by CAA. According to the CAA, the landing gear was still in extended position because the crew had not obtained the stabilized positive climb rate, which was technically in conformance with the approved flight manual. In light of the TOGA button finding, the CAA stated that the recorded behaviour on the aircraft showed more evidence that the TOGA button had actually been activated by the crew. The Georgian CAA insisted that the accident was mainly caused by the severe weather condition in the area, the crew's decision to continue their flight despite the prevailing bad weather and the ATC's failure to inform the crew on the deteriorating weather condition in Kinshasa. ==See also==