Scheduled Revenue Flight

A press conference provided by the Mozambican authorities on 21DEC2013 reported that CVR analysis revealed that the captain was alone in the cockpit which was locked. The copilot tried to enter without success and was knocking on the door several times, without answer or any reaction on part of the captain who engaged the aircraft in a descent rate of 6,000 feet per minute until impact with the ground. Several warning sounds and alarms were not responded to. On April 15, 2016, the Directorate of Aircraft Accident Investigations (DAAI) of Namibia confirmed in its final report that the accident was caused by the inputs to the auto flight systems by the person believed to be the Captain, who remained alone on the flight deck when the person believed to be the co-pilot requested to go to the lavatory, caused the aircraft to departure from cruise flight to a sustained controlled descent and subsequent collision with the terrain. Investigations revealed that the captain suffered personal events during the past year, such as a divorce, the death of his son in a car crash and one of his daughter that underwent heart surgery.

Systemic weaknesses in identifying and controlling the levels of risk, non-functional safety management system in the airline and lack of control over the level of crew training by aviation authorities at all levels (Tatarstan Civil Aviation Authority, Russian Civil Aviation Authority), that resulted in an unqualified crew being assigned to the flight.
During the go-around the crew did not recognize that the autopilot had disconnected resulting in the aircraft impacting ground in a complex spatial position (nose up upset). The captain, pilot flying, lacked the skills to recover the aircraft from the complex spatial upset (lack of Upset Recovery), that led to significant negative G-forces, loss of spatial orientation sending the aircraft into a steep drive (75 degrees nose down) until impact with ground.
The go around was required because the aircraft on its final approach arrived in a position from which landing was impossible as result of a map shift by about 4000 meters (aircraft systems determining the position of the aircraft in error), the inability of the crew in those circumstances to combine aircraft control and navigation with needed precision, and the lack of active support by air traffic control during prolonged observation of significant deviation from the approach procedure.
The following factors were considered as contributory:
The captain not having had primary flight training,
The flight crew members being allowed to upgrade to Boeing 737 without satisfying the required qualifications including the English language,
Methodical shortcomings in retraining as well as verification of results and quality of training,
Insufficient level of organisation of flight operations at the airline, which resulted in failure to detect and correct shortcomings in working with the navigation equipment, pilot technique and crew interaction, including missed approaches,
Systematic violation of crew work and rest hours, a large debt of holidays, which could have resulted in accumulation of fatigue adversely affecting crew performance, Simulator training that lacked a missed approach with intermediate height and all engines operating,
Increased emotional stress to the flight crew before deciding to go around because they could not establish the position of their aircraft with the necessary precision to accomplish a successful landing,
Violation of the principle "Aviate, Navigate, Communicate" by both flight crew and air traffic control, which resulted in the flight crew not following standard operating procedures at the time of initiating the go around because the pilot monitoring was diverted from his duties for a prolonged period and did not monitor the flight parameters,
The fact that the crew did not recognize the autopilot had disconnected and delayed intervention by the crew, that resulted in the aircraft entering a complex spatial position (nose up upset),
Imperfection of simulator training programs for Upset Recovery Procedures as well as lack of criteria for assessing the quality of training, which resulted in the crew being unable to recover the aircraft from the upset,
The possible impact of somatogravic illusions,
The non-addressing of prior accident investigation recommendations, geared towards elimination of risks and establishing risk level management, had prevented the prevention of this accident,
Lack of proper supervision of issuance of pilot certificates in accordance with achieving specified requirements and qualifications,
Failure of safety management system (SMS) in the airline, lack of guidelines for SMS development and approval, lack of a formal approach to approve/agree on SMS and pilot training by the related authorities,
Deficiencies in aviation training centers' performance and absence of verification of training quality,
Lack of requirements for flight crew to be proficient in English Language for retraining on foreign aircraft types and lack of formal approach to verify language proficiency,
lack of formal approach to conduct periodic verification of flight crew qualification,
systematic violation of crew work and rest times,
lack of training of flight crew on go around from intermediate heights in manual control potentially leading to complex spatial position (e.g. nose high upset),
The map shifts in aircraft without GPS without training of crew to operate in such conditions,
Lack of active assistance by air traffic control when the approach procedure was deviated from over a prolonged period of time,
Breach of principle "Aviate, Navigate, Communicate".
Translation via www.avherald.com

A first-stage turbine wheel blade in the left engine failed due to a combination of metallurgical issues and stator vane burn-through. As a result of the blade failure, the left engine continued to operate but experienced a near-total loss of power at approximately 500 feet above ground level, on final approach to Runway 26 at the Red Lake Airport. The crew were unable to identify the nature of the engine malfunction, which prevented them from taking timely and appropriate action to control the aircraft. The nature of the engine malfunction resulted in the left propeller being at a very low blade angle, which, together with the landing configuration of the aircraft, resulted in the aircraft being in an increasingly high drag and asymmetric state. When the aircraft’s speed reduced below minimum control speed (VMC), the crew lost control at an altitude from which a recovery was not possible.

The probable cause of this accident were the sudden change of weather condition and the flight crew's failure to properly execute the published instrument approach, including the published missed approach procedure, which resulted in the aircraft impacting the terrain.
The following factors may have contributed to the accident:
- The flight crew's decision to continue the approach below the published minima
- The flight crew's selection of an altitude in the ALT SEL window below the minima, which led to misleading FD horizontal bar readings during the go-around
- Possible Somatogravic illusions suffered by the PF
- The automatic reappearance of the FD crossbars consistent with the operating logic of the aeroplane systems, but inappropriate for the go-around
- The inadequate monitoring of primary flight parameters during the go-around, which may have been worsened by the PM's attention all tunneling on the management of the aircraft flap configuration
- The flight crew's limited coordination that led to a mismatch of action plans between the PF and the PM during the final approach.

Controlled flight into terrain after the pilot suffered a spatial disorientation while cruising in unfavorable weather conditions due to the presence of the tropical storm 'Octave'.

Based on the information from the recorded statements of witnesses and Captain of the aircraft, it clearly indicates that the aircraft was attempting to land on Runway 04 with a tail-wind blowing at 270° 15kts gusting up to 25kts on the first approach, contrary to what was reported by the Captain to the investigators. The demonstrated cross wind landing on the DHC6-310 is 25kts and tailwind landing is 10kts. The aircraft was unsettled and unstable until it passed abeam the terminal building which was not the normal touch down point under normal landing condition. The flap setting on the first approach with the tail-wind condition was at 10°, which is not in accordance with company’s procedures. A tail wind landing condition that will satisfy the criteria for the DHC6-310 is not more than 10kts tail-wind and a flap setting of not more than 20°. One of the stabilized approach criterias for visual conditions (VMC) into Kudat is landing configuration must be completed by 500ft Above Ground Level (AGL) for the DHC6-310 where else if the above conditions could not be met, a go-around should be initiated. Hence, the Crew should have initiated a go-around earlier before the aircraft reached 500ft AGL on the first approach. The aircraft should be in the correct landing configuration at or below the stabilized approach altitude of 500ft AGL, since the aircraft was not stable due to the tail wind and gusting weather. The procedure carried out on the approach for Runway 04 was not consistent with MASwings’ Standard Operating Procedure (SOP) for a tailwind condition. Nonetheless, the first approach for Runway 04 though was uneventful. On the second approach from Runway 22, the wind condition was still not favorable for landing, and gusting. The aircraft was believed to be slightly low on the initial approach and was still unstable. The flap setting for the second approach for Runway 22 was at full flap (37°). As the wind was gusting, a flap setting to full-down should be avoided for the landing as stated in company’s DHC6-310 SOP. With the full-flap configuration, the aircraft had difficulty to settle down on the runway thus dragging the aircraft until abeam the tower which is way beyond the normal touch down zone.
At the point where the aircraft was approaching to land it was reported that the aircraft was hit by a sudden gust, several factors, including the following, have been looked into:
a) Why was the aircraft unable to climb after initiating the go-around?
The full flap setting would require a zero degree pitch attitude to ensure the aircraft speed is maintained. With go-around power set, the zero degree pitch would ensure a climb without speed loss. A pitch above zero degree can cause the aircraft speed to decrease and induce a stall condition resulting in the aircraft being unable to climb.
b) Was the go-around technique executed correctly, taking into consideration that the wind was blowing from 270° and gusting?
The Captain had said that "I applied maximum power and expected the aircraft to climb. At this point, the aircraft was still in left-wing high situation. I noticed the aircraft did make a climb but it was a shallow climb. I did not retract the flaps to 20°, as at that time, in my mind, the aircraft was still low."
c) Under normal conditions, the rule of thumb for initiating a go-around procedure is to apply maximum power, set attitude to climb, confirm airspeed increasing and reduce the flap setting. This procedure was found not to be properly synchronized between MASwings Manuals and DHC6-310 Series 300 SOP.
d) Were the pilots in control of the aircraft?
Based on the Captain’s statement and other associated factors, the pilots were not in total control of the aircraft.

Failure of the hydraulic system, causing the malfunction of the nosewheel steering system and the brakes.

It was determined that the loss of control that occurred on short final was the result of the combination of a human error and weather component. The pilot was surprised by the abrupt change in weather conditions on short final to Kamako runway 12. He elected to initiate a go-around procedure and increased engine power but unfortunately, low level windshear caused the aircraft to lose height and to struck the ground as its speed was insufficient. In consequence, the increase power was too low to allow the pilot to maintain the approach profile. The torsion of the blades confirmed that the engine was at full power for a go-around procedure at impact. The absence of a windsock at Kamako Airfield was considered as a contributing factor as this would help the pilot to recognize the wind component and to decide to land or to go-around in due time.

Loss of control after landing after the right hand bogie beam broke due to fatigue cracks.