On 9 March 2016, True Aviation Flight 21, an Antonov An-26 transport aircraft operated by True Aviation crashed 500 metres from Cox's Bazar Airport in Bangladesh, from where it had taken off shortly before. The twin-engine plane was attempting to return to the airport after experiencing an engine failure. Three of the four crew members on board were killed in the accident.

Background
The flight was managed by True Blue Aviation. The member of Parliament from Cox's Bazar and member of Awami League Ashek Ullah Rafique is one of the owners of the aviation company.

Accident
On 9 March 2016 the Antonov An-26 owned by True Aviation, registered as S2-AGZ and operating Flight 21 a cargo flight, was scheduled to flight from Cox's Bazar Airport to Jessore Airport. The airplane was transporting 802 boxes of fried shrimp for a total of 4.800 kg.

At 02:58 UTC according to the ATC the crew requested the startup clearance, afterwards the ATC controller informs the crew that  the visibility in the Jessore Airport is 3 km. 

The aircraft started the engines, he crew request for taxi and was clear to taxi on Runway 35 via Taxiway S. 

At 3:05 UTC the aircraft requested the takeoff clearance and was clear to take off seconds later.

Immediately after the aircraft was airborne, the pilot informs the tower that an engine had a failure, without initially reporting which one of the two engines it was to failing, but confirming only later, that it was the left engine that failed, which led the pilot to request an immediate return to Cox's Bazar Airport. 

The Air Traffic Controller advised the pilot to call for a left hand downwind approach but instead the pilot was making a right hand downwind approach at a very low altitude.

All emergency service vehicles are put in standby by controllers. The aircraft was on final approach when requested the clearance for the emergency landing, but for unknown reasons the aircraft made a low altitude Go-Around, according to the flight controller, the plane was flying at an altitude between 400 and 500 ft.

The surviving Flight navigator confirmed in a later statement that the ATC had actually warned the pilot to call for a left hand downwind approach, The ATC repeatedly keep calling the aircraft but there was no response from the crew and later the communication was lost from the aircraft. At 03:32 UTC the airport authorities could only know of  the crash of the plane at approximately 3 kilometers east of the airport, on the Bay of Bengal.

Crew
The crew consist of four members all of wich are Ukrainian nationals. Three of the four members were killed and one survived.

The dead were:

 57-year-old Captain Murad Gafarov, who had 13.315 total flight hours, including 6,809 hours on the An-26.
 27-year-old Co-pilot Ivan Petrov, who had 1,438 total flight hours, including 1,195 hours on the An-26.
 36-year-old Flight Engineer Kulisn Andriy, who had 3,924 total hours, including 2,946 hours on the An-26.       

The survivor was: 

 48-year-old Flight Navigator Vlodymyr Kultanov, who had 3,924 total hours, including 2,946 hours on the An-26.

Aircraft 

The aircraft involved was an Antonov An-26, entered in service on 15 February 1984, on 17 July 2014 the aircraft entered in service in Bangladesh. The aircraft was powered by two Ivchenko Al-24 turboprop engines. The aircraft had 16,379 hours at the time of the accident. 

The aircraft was owned by Air Urga and was on lease to True Aviation.

Rescue

The rescue operations was conducted by Bangladesh Navy, Coast Guard, fire service and Civil defence helping the local fishermen that are rushed to the accident scene to rescue the survivors, until the arrival of doctors.

Investigation 

The Air Accident Investigation Group Bangladesh (AAIGBD) open an investigation on the accident. Because the nationality of crew members was Ukrainian, the National Bureau of Air Accidents Investigation of Ukraine (NBAAI) joining the Bangla authorities.

On the same day the Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) was recovered. Both recorders they was apparently not damaged externally, both are Ukrainian manufactured because the aircraft was old, no construction and serial number are available. 

On 11 April both recorders are sending at National Bureau of Air Accidents Investigation of Ukraine headquarters in Kiev to be inspected, because in Bangladesh there are no available facilities for the analysis of flight recorders. According to the NBAAI analysis of CVR was not possible for the internal damage to the equipment, but the FDR was in good conditions therefore it is was possible the readout of the flight data, after decoding the data Ukrainian authorities make an animation of the flight and the crash delivered to AAIGBD.

The AAIGBD can make a preliminary analysis which are the followings:

 The An-26B aircraft was on a schedule commercial cargo flight from Cox's Bazar to Jessore (VGCB to VGJR). This was the first flight of the day and the aircraft was serviceable without any MEL.
 The crew had proper rest as per records kept by the operator. The weather condition was acceptable for the flight. During the Take Off roll the aircraft lost initial power from takeoff power to cruise power in the left engine at around 80 km/h. The crew continued the Take Off despite the engine problem. Immediately after airborne the left engine had fully failed.
 The crew had taken off from runway 35 but after the engine failure the crew initially tried to land back in opposite direction runway 17. The crew could not align the aircraft with the runway 17 and discontinued the approach.
 Then pilots decided to make an approach for runway 35. The control tower had cleared them accordingly. The aircraft was flying a right hand downwind at around 1000 feet with a IAS of 300 km/h in clean configuration.
 According to the available data and statements, the aircraft was fully configured for landing and stable at around 3.5 NM from the runway. But at 1.2 NM for reasons unknown the captain decided to Go Around.
 During the process of Go Around the aircraft had crashed at approximately 3 km west of the airport into the sea.

Other findings are the following:

 The aircraft had valid Certificate of Airworthiness.
 The crew had valid licenses with appropriate ratings and medical fitness certificate to operate the flight. The Captain was the Pilot flying.
 The reported weather condition was within limitation for operating the flight.
 The load sheet for the flight shows the aircraft was carrying the maximum payload of 4800kg.
 There was no load sheet available to verify aircraft's load, fuel or Take Off weight. The operator on enquiry informed that the load sheet was on board the aircraft and perished with the aircraft when it crashed. As per regulations three copies must be prepared before departure. One copy is to be left at the departing airport, second copy is to be retained with the flight document and one copy is to be kept at the arriving airport.
 The FDR report shows that during Take Off roll the left engine lost power to cruise mode at 80 km/h .The left engine lost full power within 60 seconds after initial loss of thrust during the take off roll.
 The aircraft lift off speed with full all up weight is between 195-200 km/h.
 As per the FDR report submitted by NBAAI the reason given for engine failure is due to a drop in oil pressure in the torque meter system.
 As per Navigator's statement the captain initially tried to maneuver the aircraft to land in Runway 17 but was unable to line up with the runway. The FDR report also shows that the crew made an eight shape maneuver  after takeoff.
 The captain discontinued the approach and joined right down wind at an altitude of 300 meter with a speed of 300 km/h. The surviving navigator could not explain as to why the captain decided to make a Go Around though the aircraft was stable and more or less in line with Runway 35 with full landing configuration and approximately 3.5 NM from the runway end. The FDR report also shows that the crew made an eight shape maneuver after takeoff.
 No data could be detected from CVR due to absence of synchronization signal.
 As per the Navigator's statement the captain decided to Go Around at about 100 meter and at approximately 1.2 nm from the runway.
 A video footage taken from the ground shows that the during Go Around process the under carriage was retracted. The FDR report shows that the flaps were also retracted in phases to fully up position.
 As per the statement of the Navigator and also analysis of the FDR report the IAS at this stage was at approximately 225 km/h and the aircraft was flying at an altitude of 100 meter.
 The Navigator's last monitored altitude of the aircraft was 20 meter at an IAS of 215 km/h.
 It was also reported by the Navigator in his statement that the crew found it difficult to control the aircraft in finals.

Final Report 
The final report on the accident was released by the AAIGBD on 20 April 2017 and stated that the probable causes are:

 Failure to initiate a rejected take off during take off roll following the indication of engine failure;
 Failure to adhere to the company SOP following the detection of the engine failure during take off;
 Considering the poor visibility at Cox's Bazar Airport, diverting to the alternate airfield Chittagong Airport located only 50 nm away that has the provision for full ILS approach facility. This could have helped the crew in carrying out a proper one engine out precision approach landing;
 The aircraft flew at a speed much lower than the clean configuration speed. The aircraft flew at 225 km/h in clean configuration whereas the minimum clean configuration speed is 290 km/h.
 As per the FDR data the aircraft stalled while making a turn towards the side of the failed engine at a very low altitude.

Some recommendations are make and they are the followings:

 All relevant flight crews of AN-26 aircraft need to be properly trained to coup up with engine failure procedure during and immediately after take off
 Emphasis should be given during CRM Courses for decision making process; 
 Maintenance status of all AN-26 aircraft shall be enhanced to ensure prevention of engine failure occurrences at any stage of flight.

References

True Aviation An-26 crash
Aviation accidents and incidents in 2016
Aviation accidents and incidents in Bangladesh
History of Chittagong Division
Accidents and incidents involving the Antonov An-26
March 2016 events in Bangladesh
2016 disasters in Bangladesh
Airliner accidents and incidents caused by engine failure