Boeing 737-500 VQ-BBN 17.11.2013

      According to the information recieved the fatal accident with Boeing 737-500 aircraft operated by "TATARSTAN" Airlines of Tatar ITD of FAA occured in Kazan airport on November 17, 2013 in 7:23 Moscow time.
      Six crew members and fourty four passengers on board were killed. The aircraft was destroyed. 
      Based on Russian Legislation and in accordance with "Civil aircraft accident and incident investigation regulations in Russian Federation" approved by RF Government Regulation from June 18, 1998 № 609 and according to the requirements of Annex 13 to Convention on international civil aviation, the Interstate Aviation Committee Investigation team conducts investigation with participation of FATA specialists and other concerned authorities. 
      The Investigation team proceeded to work at the accident site.
     

     The Interstate Aviation Committee Investigation team of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines informs that CVR flight recorder was detected at the accident site. 
      The container sustained substantial damage.
    

     Investigation team of the Interstate Aviation Committee of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines informs that CVR flight recorder container was detected at the accident site.
     The recorder container sustained substantial damage.
     

     The Interstate Aviation Committee (IAC) Investigation team of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines informs that FDR and CVR data containers (so called black boxes) detected at the accident site are delivered to the Interstate Aviation Committee. 
      Containers opening, flight recorders registered data read out and its decoding will be held in the IAC laboratory.  
     

     The Interstate Aviation Committee (IAC) Investigation team of the accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines informs about the preliminary results of FDR data decoding.
      During approach the crew couldn't perform standard approach in accordance with regulatory documentaion specified by chart. After assessing the aircraft RWY attitude as "non-landing", the crew reported to controller and initiated go-around in TOGA (Take Off / Go Around) mode. Provided that during the approach one of two autopilots was disengaged and further operation was performed in manual mode.
      The engines reached thrust level close to full. The crew retracted the flaps from 30 degrees to 15 degrees position.
      Affected by the upturm moment generated by the engine thrust the aircraft started to climb reaching the pitch angle about 25 degrees. Indicated speed started to decrease The crew retracted the landing gear. Since initiating the go-around maneunver up to this moment the crew didn't perform control actions through the yoke.
      After the air speed decrease from 150 to 125 knots the crew started control actions threw the yoke pitching nose down resulted in climb abort, descent initiation and air speed increase. Maximum angles of attack didn't exceed limitations.
      After reaching the altitude of 700 m the aircraft initiated a steep nosedive with a pitch angle reaching -75° by the end of the flight (end of the record).
      The aircraft collided with terrain at high speed (exceeding 450 km/h) and high negative pitch angle.
      About 45 seconds passed since the moment of go-around maneuver and the moment of record ending.
      Power units operated up to the ground impact. No event signals indicating aircraft systems and units and engines failures were indicated.
      FDR data analysis and decoding are in progress.
      The Investigation team emphasizes that during CVR opening the protected pod with tape-driving mechanism was absent. The Investigation team continues unit search. 
      Investigation team continues its activities at the accident site. Flight documentation of the Airlines and crew training has been stadied including highly qualified pilots having extensive practice in this type of aircraft operation in leading Russian airlines. Maintenance documantation of the Airlines including aircraft maintnence and airworthiness in accordance with international regulations has been studied. Ground recorders information, meteorological condition and aviation traffic service data have been analysed. 
      The IAC Investigation team will provide regular information on the investigation progress.

     The Interstate Aviation Committee (IAC) Investigation team of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines informs that CVR unit was detected at the accident site.
      Detected unit will be delivered to the IAC for necessary activities.
      Large workscope on further FDR decoding and analysis including Kazan-Domodedovo flight priopr to the emergency one and other flights is in progress in the the IAC laboratory.
      Activities on sychronization and cooperative processing of ground and airborne recorders are planned. 
      Investigation team work is in progress at the accident site. 

     In connection with the issues on causes and versions of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" Airlines appeared in mass-media the Interstate Aviation Committee (IAC) Investigation team informs:
      According to on-board flight recorders no aircraft systems, accessories and controllers failures were registered. The aircraft engines operated up to ground impact.
      The IAC repeatedly explained that the ICAO standards on so called "old" and "new" aircraft don't exist. The main thing for safety is aircraft airworthiness but not its age. There is no direct correlation between aircraft fatal accidents and its age. In the last five years the number of fatal accidents with aircraft with passenger capacity more than 50 seats is the same for aircraft up to 5 years and over 30 years in the world including Russia. According to avaliable information the avarage age of Boeing 737-500 aircraft operated in the USA is  20,4 years. In Europe – 20,3 years. More that 7600 aircraft series Boeing are operated in the world. Their accumulated age is 257,6 million flight hours. The rate of fatal accidents with Boeing 737-500 aircraft per 100 flight hours is less than 0,05.
      The Interstate Aviation Committee requests to refrain from publicity and populism agains the background of the great tragedy. It hurts relatives and friends of those killed, feverishes air-tranport branch activity.
      The IAC Investigation team continues its professional activity on ascertaining of circumstances and causes of the fatal accident in accordance with the ICAO standards. 
    

     The activities on transcript of data registered at CVR recorder of Boeing 737-500 aircraft operated by "TATARSTAN" Airlines crashed in the airport of Kazan on November 17, 2013 are in progress of the IAC laboratory. Considerable workscope on recognition and identification of crew members voices, following synchronisation of registered data and airbone recorders is to bo done.
     The IAC Investigation team continues its work.

     The activities on identification of aircraft cockpit voices registered on CVR are held in the Interstate Aviation Committee laboratory are held. Specified experts signed the preliminary crew speech protocol. No evidences of unauthorized persons presence in cockpit were identified at this stage. Activities on voices decoding and identification are in progress.

     The Interstate Aviation Committee Investigation team of the fatal accident with Boeing 737-500 aircraft operated by "Tatarstan" airlines informs that based on preliminary analysis of flight recorders and other avaliable information in accordance with Aircraft Accident and Incident Investigation Regulations in the Russian Federation the Commission consideres it appropriate to implement the following operating recommendations on flight safety development:
      1. Consider advisability of additional sessions and training for flight personnel on:
• go-around flight maneuver practice in direction mode highlighting intermediate altitude leaving when the altitude value which is necessary to ascend during leaving procedure is close to current value and radio contact as well;
• aircraft upset identification and upset recovery practice;
• aircraft systems operation procedure and features (autopilot, flight-director) during approach and go-around flight maneuver depending on particular conditions;
• studying aircraft navigation system features (FCOM section: FMC Navigation Check и Navigation Position).
      2. Consider the need of ATM experts operating procedures modification concerning provision of more active assistance to aircraft crew (in case of significant off-track) in case of technical feasibility for example by requesting crew to perform vectoring for aircraft final course. 
      3. Holding of flight-engineering conference on exchange of best practices of Boeing 737 family operation.
     Specified recommendations in a form of the Following report on the aircraft accident in accordance with PRAPI were reported to Federal Air Transport Agency.
      Flight documentation inspection of "Tatarstan" airlines on initial training and Boeing 737 conversion and periodic training and crew members proficiency check is in progress. 

      The IAC Investigation team of the accident with Boeing 737-500 operated by "Tatarstan" Airlines informs that activities of engeneering and technical subcommisson on study and analysis of aviation equipment operability including elevator control systems in emergency flight are completed.
      A number of studies was made in order to evaluate the elevator control system operability; 
• 3D tomography of hydralic servos of elevator right and left sides;
• hydralic servos complete disassembly and evaluation;
• bed tests of hydralic servos main junction boxes (rods);
• dissection of some hydralic servos elements for evaluation of inner surfaces condition; 
• mathematical simulation of aircraft motion and elevator control system operation using flight recorders recordings.
      Engineering analysis of two elevator hydralic servos with simulation of all possible options of the main junction boxes jamming was held as well.
      History of this type of hydralic servo operation and investigation materials of the events connected with emergency operation of elevator control system were studied. The analysis indicated that the circumstances of the events connected with emergency operation of elevator hydralic servos differ from the circumstances of the emergency flight.
      Based on all carried out activities the engeneering and technical subcommission concluded that there is no evidence of aviation equipment failure in emergency flight on flight recorders as well as on remained components, engines and systems of the aircraft including elevator control system.
      The Investigation team is completing activities on ascertaining all accident causes and factors.
     

     The Investigation team of the Interstate Aviation Committee (the IAC) has completed activities on investigation of the fatal accident with Boeing 737 500 VQ-BBN aircraft operated by "Tatarstan" Airlines.
     During the investigation all necessary works were held including: field stage of the investigation including making crocks of the accident site as well as full layout of the aircraft remained fragments; decoding and analysis of ground-based and onboard recording facilities; special analysis of the elevator hydraulic servos; mathematical flight stimulation; flight assessment of the crew actions performed by the test-pilots and experienced airline pilots; simulator experiment; studying data about the crew training, work-test schedule, flight operation management and flight safety management system in the Airline; studying medical documents and forensic medical examination results; studying data about technical maintenance operations and aircraft maintenance operations.   
      Investigation team prepared the Final report in accordance with its work results.
      In accordance with the standards of the International Civil Aviation Organization after translation in English the Report project will be directed to the authorized representatives: NTSB of the USA, AAIB of Great Britain, and BEA of France. Designated states took part in the investigation.     
      
After receiving and examining of the states commentaries the Final report will be published on the official IAC web-site.
     
   

The Investigation team of the Interstate Aviation Committee has completed the investigation of the accident with Boeing 737-500 VQ-BBN aircraft operated by "Tatarstan "Airlines" JSC occurred in Kazan Airport on November 17, 2013.

The fatal accident with Boeing 737-500 VQ-BBN aircraft was caused by system defects in identification of hazard factors and risk level monitoring as well as nonoperation of safety management system in the Airline and lack of monitoring over the crew members proficiency level from aviation authorities of all levels (Tatar Interregional Territorial Department of FAA) that resulted in unprepared crew authorization for flights. 

Performing go-around flight maneuver the crew did not identify the autopilot overriding and allowed the aircraft nose up upset. Lack of PIC's skill of aircraft upset recovery resulted in significant deceleration, spatial disorientation and aircraft steep dive (pitch down angle up to 75°) down to ground impact. 

Go-around flight maneuver was caused by the aircraft non-landing setting running out to the RWY that was caused by "Map shift" effect (aircraft position indication error by airborne systems) by the rate of 4 km, the crew disability to perform composite aircraft navigation and navigation with adequate accuracy as well as absence of ATM active assistance during long monitoring of significant deviations from the approach pattern.

The accident was caused by combination of the following factors[1]:

-          lack of PIC's initial flight training;

-          authorization for Boeing 737 conversion of the crew members not fully meeting the skill requirements for application for conversion including English language course;

-          methodological imperfection of the conversion process, formal control over the conversion results and quality; 

-          low level of operation management in the airline that resulted in long-term non-elimination of identified deficiencies in working with navigation equipment, piloting technique and crew members interaction including during go-around flight maneuver;  

-          regular violation of the crew members work-rest regime and vacation liability that could result in chronic-fatigue build and negatively effect the crew members performance;  

-          lack of go-around flight maneuver element from intermediate altitude with two operating engines in training programmes;

-          increased psycho-emotional tension of the crew members before go-around flight maneuver due to the long-term failure to identify the aircraft position with an accuracy to perform landing; 

-          violation of Aviate - Navigate - Communicate approach by the crew as well as by ATM service that resulted in non-adherence to standard operating procedures by the crew during go-around flight maneuver due to the long-term distraction of the first officer from performing their duties and flight data monitoring;

-          not identification of the autopilot overriding by the crew and late interference with aircraft that resulted in aircraft nose up upset;

-          imperfection of used training programmes on the aircraft upset recovery and its quality evaluation criteria that resulted in the crew disability for the upset recovery;

-          possible effect of somatic gravitational illusions.

Non-adherence to the recommendations of the Investigation team of the accidents occurred before aimed at hazar factors elimination and risk level monitoring connected with: 

-          lack of the appropriate monitoring system for pilots licensing, compliance of crew members training with specified requirements and ratings assignment;

-          safety management system nonoperation in airlines, lack of methodological recommendations on their development and approval, formal approach to approval/coordination of safety management systems and crew training programme on behalf of the authority; 

-          imperfection of Aviation Training Center work and actual lack of monitoring over the conversion results;

-          lack of English language level requirements to the flight personnel for foreign type aircraft conversion and formal approach to English language level check; 

-          formal approach to the line and proficiency flight personnel check;  

-          regular violation of work-rest regime;

-          insufficient training of flight personnel for go-around flight maneuver from intermediate altitude, aircraft manual operation mode and during it upset recovery; 

-          "Map shift" effect at not equipped with GPS aircraft and insufficient crew members training for operation in such conditions;

-          need of active assistance to the crew from ATM service in case of detection of long-term deviation from specified procedures;

-          violation of "Aviate - Navigate - Communicate" approach couldn't prevent the accident. 

  The appropriate safety recommendations based on the investigation results were developed.

[1] In accordance with the ICAO's Manual on Aircraft Accident and Incident Investigation (DOC 9756 AN/965) factors are presented in logical order without the priority evaluation. 

Прикрепленные документы:

Протокол итогового заседания комиссии по расследованию (1.36 MB)

Особое мнение представителя Росавиации (7.88 MB)

Ответ Комиссии по расследованию на особое мнение (2.4 MB)

Комментарии государства-разработчика на особое мнение (240.33 KB)

Перевод комментариев государства разработчика и изготовителя самолета на особое мнение (228.57 KB)

Final Report (19.9 MB)