Já existem 57 respostas neste tópico, contribua você também!

[Pilot SBBH]

Eu citei abismado o fato de nao terem optado pela arremetida, mas nesse caso ai, "arremetida" entende-se por APPROACH TO STALL RECOVERY (potencia de firewall, pitch entre 7,5 e 10º e asas niveladas) e depois com velocidade apropriada e razão de subida positiva, o TO/GA propriamente dito.

Pq como disseram ai alguns, de nada adianta atolar o dedo no TO/GA se o pitch já tá qse na vertical.

Isso com certeza evitaria uma deterioração das condições de perda de conciencia situacional que já estava grave naquela hora ali do Stick shaker. E um procedimento desse tipo não é nenhum coelho retirado da cartola não... é condicionamento por treinamento exigido pela Boeing.

Obviamente depois que tudo ocorre fica fácil argumentar. Certamente aparecerão outros fatores que contribuiram seriamente para a situação a que esses pilotos submeteram esse 737.

Editado por Pilot SBBH, 08 de março de 2009 - 15:58 .

• Back to top

[Omykron]

Segundo o manual de treinamento da VASP, de JAN 1990, existem 3 tipos de treinamento a serem efetuados em caso de Approach to Stall no caso do Boeing 737-200. Para fins de citação, irei omitir os dois primeiros tipos, já que tais procedimentos são similares ao terceiro tipo, diferenciando-se apenas no quesito configuração da aeronave.



---

O treinamento do Approach to Stall visa familiarizar o aluno com os avisos de estol e a técnica correta de recuperação. O aviso de estol pode ser natural (Initial Buffet) ou artificial (Stick Shaker), sendo que o piloto deve iniciar a recuperação tão logo perceba o sinal inicial do Buffet ou do Stick Shaker que, no caso do 737-200, ocorre com uma margem de 10%, ou mais, sobre a velocidade de estol.

(...)

Terceiro tipo de Approach to Stall

Desacelere em IDLE; a 210 kt peça Flaps 1; a 190 KT, Flaps 5; a 180 KT ajuste o N1 em 70%; a 170 KT, Gear Down e Flaps 15; a 150 KT, Flaps 2; a 140 KT, Flaps 40; continue mantendo a altitude observando o aumento de PITCH a medida que decresce a velocidade. Ao primeiro sinal de STICK SHAKER ou BUFFET (BUG-15), aplique GO-AROUND EPR e abaixe o nariz até 5 graus de PITCH UP, quando a velocidade atingir BUG, inicie a recuperação de altitude. Ao atinger a altitude original, com um mínimo de BUG + 5 KT, sem alteração na posição dos flapes e do trem de pouso, considere a manobra terminada. Numa situação real, não s altera a posição dos flapes ou do trem de pouso, a menos que seja necessário arremeter. Em princípio, a aeronave prosseguirá para pouso após a recuperação de velocidade.

(...)

Approach to Stall durante procedimento IFR ou trafego visual:
Em um determinado momento, o instrutor poderá dizer ao aluno: "Simule agora um APPROACH TO STALL". O aluno devera simplesmente colocar as manetes em IDLE e Procurará manter a atitude ou rampa de planeio, fazendo de conta que se esqueceu de controlar o empuxo. Ao primeiro aviso de estol, o piloto faz a recuperação (GO-Around EPR, PITCH UP +5º até recuperar a velocidade de APP) e prossegue no procedimento até o pouso, a menos que haja necessidade de arremeter. A recuperação é muito simples, inclusive na reta final com Flaps 40. Em princípio, não se deve alterar a posição dos flapes e do trem de pouso.

---
No video do link abaixo, vemos um vôo de testes em um 737-400 com treinamento de approach to stall para verificação do sistema de auto-slat, no approacho to stall do primeiro tipo, porém configurado em FLAP 5
http://www.youtube.com/watch?v=a4V8W31YwTQ
aqui um voo de teste com treinamento de estol limpo.
http://www.youtube.com/watch?v=WlTzamnHHlg

• Back to top

[Lear_60]

Claro que sozinhos os motores não fazem nada, mas se ao primeiro sinal do stick shaker já fosse acionado o TO/GA e feito o procedimento normal de recuperação, o resultado poderia ter sido outro.
O problema é que o pitch ficou quase que vertical e a situação se deteriorou demais pela demora na tomada de qualquer ação pela tripulação.

• Back to top

[Zaza]

Ativar esse comando numa situação de estól - iminente ou em andamento -, isoladamente, sem outras ações correspondentes, não necessariamente fará com que a aeronave consiga se recuperar, porém, na maioria dos casos, a situação poderá se deteriorar mais ainda e a recuperação se tornar extremamente complicada ou até inviável.

O TO/GA cancelaria o modo APP, "deixaria" o avião nas mãos deles (pois estavam em APP Single Channel até onde sei), aumentando a consciencia situacional e o A/T com certeza não manteria as manetes voltando. Não que seja essa a manobra correta do Stall Recovery, mas certamente já adiantaria de alguma coisa sim.

• Back to top

[Wind Sand and Stars]

Problema é que acionando TOGA e com o avião já trimado para cabrar (pelo AP) somando-se a tendência de cabrar devido aos motores na asa, numa situação de "pré estol" próximo do chão não há muito tempo para reação, arrisco a dizer que eles ficaram sem autoridade de profundor mesmo com o manche (eventualmente) todo travado devido à situação de trimagem

• Back to top

[Clipper]

Srs., muito válida a colocação de todos, mas vejo a situação da seguinte forma:

Deixando qualquer pré-julgamento de lado em relação ao que pode ter ocorrido com aquela aeronave, para ser feita apenas uma análise de uma condição imaginária, em outras palavras, um cenário no qual um B737 está com velocidade bem abaixo da Vref, com flaps na posição 40, com a potência em idle, em vôo descendente, abaixo de 1000 pés agl e IMC, em primeiro lugar, seria essencial definir as manobras entre recuperação de estol e arremetida. Existe nessa combinação prioridades, e a arremetida jamais poderá ser simultânea ou vir em primeiro lugar, mesmo quando é difícil dizer quando termina uma ação e começa outra. No meu modo de ver, é inquestionável a necessidade de recuperar inicialmente o controle de fato da aeronave, o que levará em alguns casos ações que contrariam todo o princípio de um procedimento evasivo como é uma arremetida. O mesmo pode ser dito numa recuperação em condições de W/S. Sim, para qualquer uma das circunstâncias é primordial o ajuste de potência, e no caso de estol, ela, a tração, deverá ser maior do que o ajuste programado pelo TO/GA - quer seja para uma razão de 2000 fpm ou de N1 máximo (de GA). Se houver uma troca de prioridades, sem o controle efetivo da aeronave, principalmente de pitch e lateral, não seria impossível imaginar um piloto colocando o avião numa atitude além de um limite previsto para a recuperação de estol, quer seja com contato iminente com o solo ou não, que poderá resultar na entrada num estol pleno (supondo que a aeronave ainda estivesse numa condição de pré-estol) ou, no caso de se encontrar de fato em estol, correr o risco de desdobramentos imprevisíveis, como a entrada num parafuso. Resumindo: perda total de controle ou até mesmo a entrada chão a dentro em plena potência. Vale salientar que ao comandar o TO/GA a aeronave reagirá conforme a sua programação, isto é, nada muito diferente do que está descrito de maneira genérica nos manuais do B737, que não é tão abrangente em termos de “inteligência” suficiente para discernir se o avião está muito abaixo de uma altura de segurança com relação ao solo, em vôo com bank angle excessivo, com um piloto completamente fora do "loop", ou se no caso dele seguir o que for apresentado pelo sistema da aeronave (isso se tudo estiver funcionando de forma adequada), ele, o A/S, simplesmente induzí-lo para uma armadilha irremediável.

Zaza: Numa situação que o piloto perdeu noção do que está acontecendo com a aeronave e seu automatismo, entregar a recuperação da aeronave para um TO/GA pode ser uma saída, e não tenho a pretensão de querer contestar a sua forma de ver. Porém, quer seja num vôo automático que ainda se mantém sabemos lá como, ou num vôo manual, depois que aeronave desacoplou sem motivo aparente o automatismo, o avião deve ser recuperado de uma situação de estol, caso contrário, o resultado poderá ser tão catastrófico quanto o tema que estamos debatendo.

A respeito do treinamento de estol, citado pelo Omykron: é pouco provável que exista uma empresa aérea sequer que simule seus treinamentos - obviamente no simulador, não na aeronave – com o seguinte cenário imaginário: vôo em curva, flaps 15, trem de pouso embaixo e a 1500 pés agl, ou, para outra condição, numa final, abaixo de 1500 pés agl e flap de pouso, numa condição teoricamente parecida com o que estamos discutindo. Portanto, há, sim, como princípio, um condicionamento do piloto, conforme a instrução do fabricante e da autoridade aeronáutica, isso quando ele(a) realmente leva a sério que uma condição como essa poderá acontecer um dia com tripulantes altamente experientes e qualificados, no entanto, ao fazer esse treinamento muito acima da altitude que tal cenário poderá se desenvolver, o que é usado pela maioria das empresas aéreas como referência para o programa, o “fator risco” não é devidamente enfatizado, e não é anormal, portanto, em muitos casos, ver pilotos perdendo 500 ou até mesmo 1000 pés numa recuperação, num treinamento feito a 10.000 pés. E não seria surpresa, também, no final, ouvir o instrutor dizer: fim de exercício, vamos para a próxima manobra do programa de treinamento.

Como sempre, um bom debate.
Abs.

• Back to top

[Mastercaptain]

A perda de controle em um avião, é hoje uma das grandes preocupações e um dos motives para vários acidentes fatais na aviação do mundo todo. Os pilotos estão sujeitos a ficarem repentinamente expostos a uma infinidade muito grande de situações em que possam perder o controle do avião.

Conceitualmente uma aeronave encontra-se em uma situação de “upset” quando:

Seu angulo de ataque for superior a 25 graus positivo.
Seu angulo de ataque for superior a 10 graus negativo.
Seu ângulo de inclinação lateral for superior a 45 graus.
E finalmente estar com qualquer uma das 3 condições acima em velocidade inapropriada.

Na intenção de evitar as características inaceitáveis acima, e evitar um “upset”, nós pilotos temos de ter em mente que : Os fundamentos de aerodinâmica se aplicam para todas as aeronaves, do Paulistinha ao 747. E que a recuperação de uma attitude anormal também tem de ser baseada nos mesmos princípios aerodinâmicos .

Normalmente os pilotos comerciais são bem familiarizados com sua aeronave, em condições normais. No entanto quando uma aeronave entra em uma situação de vôo anormal, a maioria dos pilotos tem dificuldades em lidar com a situação. Salvo pilotos que praticam acrobacia , vôo à vela e outros esportes aeronáuticos de fim de semana.

Quando uma grande aeronave sai de seu envelope normal de vôo,é possível encontrar uma situação em que aumentar a potencia dos motores não resolve uma condição de “upset”. Aumentar o ângulo de ataque em alguns casos só deteriora a perda de attitude.
Compreender e saber gerenciar a energia de seu avião, saber lidar com o “pitch” e os controles laterais e direcionais são fundamentais para situações de “upset”.

A alguns anos atraz o antigo DAC ,exigiu que as empresas desenvolvessem um treinamento em simulador para uma manobra chamada “upset-recovery”.

Esta manobra que esta ainda em uso nas melhores empresas da aviação é subdividida nas seguintes categorias:
• Controlled flight into terrain.
• Takeoff safety.
• Turbulence.
• Turbulence avoidance.
• Windshear.
Esta manobra em simulador ajuda os pilotos a saírem de situações como:
• Stall recovery.
• Nose high, wings level.
• Nose low, wings level.
• High bank angles.

Empresas com esmero no treinamento de seus pilotos ,com programas adequados, não cobrem apenas treinamento para “upset-recovery” mas treinamentos de consciência situacional que evitem para que os pilotos não coloquem-se em situações anormais. E se por motivos externos como Wind-shear ou esteira de turbulência for encontrado, saberão gerenciar a situação

• Back to top

[catrapo]

Aprioximaçao final eh uma fase critica, se o pilot flying nao percebeu que a veloc drenou pra abaixo da vref em 40 nós acho que ele deveria estar no aeroclube ainda, pq pelo menos no pouco tempo de comercial que eu tenho uma das coisas que se priorizam, que chega a ser neurotico, que tem callout, que tem gente que exagera e num mero dreno de 1kt abaixo da vapp grita SPEEDDDDD!!! nao é possivel que ninguem tenha percebido...deram mole pelo visto. eu nao condeno, erros acontecem mas olhando de fora assim eh tao bobo que chega a ser surreal. quanto ao radio altimetro ninguem olha, pelo menos nao antes de chegar mais perto da pista... o fato eh que pelo visto o comando ficou mostrando como se lia o checklist e meio que cagou pro que o aviao estava fazendo, tanto eh que o motor ficou reduzido 100 segundos, sinistro. o mais engraçado que o 737 tem um lance que quando a veloc baixa da minimun maneuver speed o velocimetro pisca ambar , eu ja vi isso aocntecer uma vez que o piloto automatico deu uma sequelada numa curva e deixou a velocidade cair, tivemos que intervir e acelerar manualmente. pra nao ver isso so se nao estiver olhando... melhor acreditar que eles perderam informaçao de speed, o tal do unreliable airspeed non normal check, que se foi a baixa altura realmente eh meio tosco... até perceberem F...

lamentavel.

• Back to top

[Max_NG]

Pessoal, tudo bem??

Desculpe-me se não notei algum comentário anterior... mas ALGUEM percebeu um GDE X da questão???? o MESMO problema com o altimetro havia ocorrido nos ultimos 8 voos da aeronave.... inclusive alguns até gravados nas ultimas 25h do FDR... E como fizeram nas vezes anteriores?

Não era o caso de um flight status para a referida aeronave, ou um briefing previo da parte de manutenção....??

Querem melar só pro lado dos pilotos, mas acho que a Turkish vai levar uma puxadinha de "oreia" nessa tbm....

Provavelmente esta informação estava no technical log da aeronave, não tenho a MEL/CDL em mãos, mas não haveria alguma restrição para o despacho??

Embora houve uma falha de monitoramento, ao que parece TODOS foram pegos de surpresa... e isso não precisava ter acontecido, uma vez que já havia ciencia sobre o problema!!

GRAVE hein..

Abraços

• Back to top

[Omykron]

Boeing emite boletim técnico a todos os operadores de equipamento Boeing 737 e BBJ no mundo referente ao acidente em Amsterdã.

-------------
BOEING COMMERCIAL AIRPLANE GROUP
FLIGHT OPERATIONS TECHNICAL BULLETIN
NUMBER: 737-09-2 R1
DATE: March 30, 2009

These bulletins provide information which may prove useful in airline operations or airline training. This information will remain in effect depending on production changes, customer-originated modifications, and Service Bulletin incorporation. Information in these bulletins is supplied by the Boeing Company and may not be approved or endorsed by the FAA at the time of writing. Applicable documentation will be revised as necessary to reflect the information contained in these bulletins. For further information, contact Boeing Commercial Airplane Group, Chief Pilot, Flight Technical, P.O. Box 3707, Mail Stop 14-HA, Seattle, WA, USA 98124-2207, Phone (206) 5449610, Fax (206) 544-9687, SITA: SEABO7X Station 627.

SUBJECT: Flight Crew Monitoring During Automatic Flight

ATA NO:

APPLIES TO: 737 All

Background Information

An erroneous Low Range Radio Altimeter (LRRA) has been identified in connection with a recent 737-800 accident.

The Digital Flight Data Recorder (DFDR) data indicates that the crew was using both the autopilot and the autothrottle during an ILS approach. The right LRRA was providing accurate data to the first officer’s display and the left LRRA was erroneously providing a reading of -8 feet to the captain’s display. No amber RA flag was displayed because the left LRRA system did not declare the data invalid.

On all 737s, the autothrottle logic uses left radio altimeter data if the left radio altitude is being displayed. This is regardless of the autopilot selected. On the 737NG, if the left amber RA flag is displayed in place of radio altitude, the autothrottle will use right radio altimeter data instead. On the 737-200 and 737-300/400/500, the autothrottle computer is only connected to the left radio altimeter; therefore, if the left RA failure flag is displayed, there will be no radio altimeter inputs to the autothrottle.

In this event, when the airplane descended through approximately 1950 feet on the approach with flaps extended beyond 12 ½ degrees, the autothrottle erroneously sensed that the airplane was in landing flare. The thrust levers were retarded to the idle stop where they remained for approximately 100 seconds. For the first 70 of the 100 seconds, idle thrust was sufficient to maintain the selected airspeed. During the next 30 seconds, airspeed decreased below the selected MCP speed to approximately 40 knots below the
selected approach speed.

The two LRRA systems provide height above ground data to aircraft systems which include the displays, autothrottle, autopilots and configuration/ground proximity warning.
If one LRRA provides erroneous altitude readings, the associated flight deck effects may typically include:

• Large differences between displayed radio altitude.
• Inability to engage both autopilots in dual channel approach (APP) mode.
• Unexpected removal of the Flight Director Command Bars during approach on the pilot’s side with the erroneous radio altimeter display.
• Unexpected Configuration Warnings after takeoff, during approach, or during go-around.
• Inappropriate Flight Mode Annunciation (FMA) indication of autothrottle RETARD mode during approach phase with the airplane above 27 feet AGL.
There will also be corresponding thrust lever movement towards the idle stop.
The FMA will continue to indicate RETARD after the thrust levers have reached the idle stop rather than change to ARM.

Boeing Recommendations


Whether in automated or manual flight, flight crews must carefully monitor primary flight instruments (airspeed, attitude etc.) for aircraft performance and the FMA for autoflight modes.

The following information is taken from the Flight Crew Training Manual (FCTM) and has been adapted to provide Flight Crews and Operators with guidelines which should be followed if a flight crew encounters any of the above mentioned indications.

General Guidelines

Condition:

• Large differences between displayed data.
Crew Resource Management (CRM) involves the effective use of all available resources to operate a flight safely. It is important that all flight deck crewmembers identify and communicate any situation that appears potentially unsafe or out of the ordinary.
Experience has proven that the most effective way to maintain safety of flight and resolve these situations is to combine the skills and experience of all crewmembers in the decision making process to determine the safest course of action.

Situational awareness, or the ability to accurately perceive what is going on in the flight deck, requires ongoing questioning, crosschecking, communication, and refinement of perception.

Condition:

• Inability to engage both autopilots in dual channel approach (APP) mode.
• Unexpected removal of the Flight Director Command Bars during approach on the pilot’s side with the erroneous radio altimeter display.
• Inappropriate Flight Mode Annunciation (FMA) indication of autothrottle RETARD mode during approach phase with the airplane above 27 feet AGL.
There will also be corresponding thrust lever movement towards the idle stop.
The FMA will continue to indicate RETARD after the thrust levers have reached the idle stop rather than change to ARM.

Automatic systems give excellent results in the vast majority of situations. Faults can occur at any point during an automatic approach. Many non-normal situations or scenarios are possible. The flight deck is designed so that a quick analysis and decision can be made for virtually all non-normal or fault situations using the autopilot/autothrottle indicators, FMAs, master caution system and, for fail operational airplanes, autoland status annunciations. Deviations in intended flight path or unexpected thrust lever movement may also be an indication of an automation fault.

If the flight crew is aware of a degraded Autopilot Flight Director Systems (AFDS) mode, special recognition should be given during the Approach Briefing as to how to manage the use of the automatic features.

Note:
Early intervention prevents unsatisfactory airplane performance or a degraded flight path.

When the automatic systems as described above do not perform as expected, the PF should reduce the level of automation to ensure proper control of the airplane is maintained.

The PF should not attempt to restore higher levels of automation until after aircraft control is assured.

Condition:

• Unexpected Configuration Warnings after takeoff, during approach, or during go-around.
Flight crew must ensure the proper configuration for the phase of flight. Time may be required in order to assess the situation, take corrective action and resolve the discrepancy; therefore a go-around, holding, or additional maneuvering may be necessary. Flight path control and monitoring of instruments must never be compromised.

Non-Normal Situation Guidelines

When a non-normal situation occurs, the following guidelines apply.

• NON-NORMAL RECOGNITION:

• The crewmember recognizing the malfunction calls it out clearly and precisely.

• MAINTAIN AIRPLANE CONTROL:

• It is mandatory that the Pilot Flying (PF) fly the airplane.

• ANALYZE THE SITUATION:

• Any further action should only be initiated after the malfunctioning system has been positively identified.

Additional Information

Any occurrences of erroneous display data, even if intermittent, should be reported to maintenance.

More information can be found in the Boeing 737 Flight Crew Training Manual and Flight Crew Operations Manual. Operators may want to review the following:

737 FCTM

1. Chapter 1 - Crew Resource Management
2. Chapter 1 - Callouts
3. Chapter 1 - AFDS Guidelines
4. Chapter 5 - Approach Briefing
5. Chapter 5 - Stabilized Approach Recommendations
737 FCOM

1. NP11 - Autopilot Flight Director Systems (AFDS) Procedures
2. Chapter 4 - Automatic Flight System Description
3. Chapter 10 - Flight Instruments, Displays System Description
4. Chapter 15 -Warning Systems System Description
Page 4 of 4

• Back to top

[Screamfeeder]

Aí vão algumas fotos do translado do que sobrou do avião para um hangar de Schiphol.

• Back to top

[ALK]

A Turkish continua com a bola toda...

Turk plane mistakenly lands at Georgia base
Wed Apr 8, 2009 4:14pm BST Email | Print | Share| Single Page[-] Text [+]
ISTANBUL (Reuters) - A Turkish Airlines aircraft apparently mistakenly landed at a military air base in Georgia on Wednesday, airport and airline sources said.

Pilot error probably caused the aircraft, travelling from Istanbul to Tbilisi, to land at the base located some 17 kilometres from the main passenger airport, a Turkish Airlines source, who declined to be named, told Reuters.

The Turkish state-run Anatolian news agency said 69 people were on board the Boeing aircraft. An aviation sector official in Istanbul confirmed the aircraft landed at the wrong airport.

"The plane was mistakenly landed at the military airport," the official said, on condition his name not be used. "It could be that the pilot confused the airports."

No further details were immediately available.

Turkish Airlines declined to comment officially on the reported incident.

(Reporting by Ercan Ersoy)

fonte: http://uk.reuters.com/article/worldNews/id...E53742820090408

• Back to top

[Leirbag]

A Turkish continua com a bola toda...

Turk plane mistakenly lands at Georgia base
Wed Apr 8, 2009 4:14pm BST Email | Print | Share| Single Page[-] Text [+]
ISTANBUL (Reuters) - A Turkish Airlines aircraft apparently mistakenly landed at a military air base in Georgia on Wednesday, airport and airline sources said.

Pilot error probably caused the aircraft, travelling from Istanbul to Tbilisi, to land at the base located some 17 kilometres from the main passenger airport, a Turkish Airlines source, who declined to be named, told Reuters.

The Turkish state-run Anatolian news agency said 69 people were on board the Boeing aircraft. An aviation sector official in Istanbul confirmed the aircraft landed at the wrong airport.

"The plane was mistakenly landed at the military airport," the official said, on condition his name not be used. "It could be that the pilot confused the airports."

No further details were immediately available.

Turkish Airlines declined to comment officially on the reported incident.

(Reporting by Ercan Ersoy)

fonte: http://uk.reuters.com/article/worldNews/id...E53742820090408

Eu tenho muita curiosidade em saber como esse tipo de coisa acontece.

A rota não está programada no FMC? No Navigation Display não aparece exatamente o aeroporto em que ele deve pousar?

Curiosidade:
estes dois aeroportos possuem pistas com mesma numeração?
como estavam as condições meterológicas?

Editado por Gabriel Leporace, 09 de abril de 2009 - 00:08 .

• Back to top

[Flight Instructor]

Eu tenho muita curiosidade em saber como esse tipo de coisa acontece.

A rota não está programada no FMC? No Navigation Display não aparece exatamente o aeroporto em que ele deve pousar?

Curiosidade:
estes dois aeroportos possuem pistas com mesma numeração?
como estavam as condições meterológicas?

Teve um fokker 100 da Tam que pousou em Guarapari ao invez de Vitória.

Também teve um 300 da Varig que pousou em Canoas e quando encostou no pátio perguntou para o co-piloto assim:
"UÉ o pessoal da SATA tão TUDO DE FUZIR"""

• Back to top

[Stelios the Greek]

http://4.bp.blogspot.com/_BCsaeWGNwNI/Sdzf...0-h/7731090.jpg


o de cima é o que deveria pousar, o de baixo é no qual pousou!

Editado por Stelios the Greek, 09 de abril de 2009 - 10:20 .

• Back to top

[Comet]

Também teve um 300 da Varig que pousou em Canoas e quando encostou no pátio perguntou para o co-piloto assim:
"UÉ o pessoal da SATA tão TUDO DE FUZIR"""

Na verdade foi um -200, e pousou na Lagoa Santa.............

Teve também um -200 que pousou em Araguari, em vez de pousar em Uberlandia. Aliás aconteceu exatamente o mesmo com o 737 presidencial, na época do pres. Figueiredo. Inclusive ele teria dito que iria substituir o piloto por um oficial da cavalaria........

• Back to top

[Matheus]

Eu imagino o que o cmte fala pros paxs numa hora dessas.

Abraços

Matheus

• Back to top

[Lear_60]

Reativando o tópico.

Essa semana saiu o relatório preliminar do acidente.



======================================================================

The investigation

On February 25th around 11.00 hrs The Dutch Safety Board was notified that a Boeing 737-800 of Turkish Airlines had crashed near the Polderbaan (runway 18R) of Amsterdam Airport Schiphol at 10.26 hrs.2 The investigation commenced immediately.
According to international agreements and guidelines (especially those within the European Union and the International Civil Aviation Organization) contact was made with the States involved, in this case Turkey as the State of registration and State of the operator, the Unites States of America as the State where the airplane was manufactured, and France as the State where the engines were manufactured. All parties and organisations concerned being the Turkish Directorate general for Civil Aviation, the American National
Transportation Safety Board, the aircraft operator, the aircraft manufacturer and the engine manufacturer have subsequently contacted the Safety Board. The British Air Accident Investigation Branch and the French Bureau d’Enquetes et d’Analyse have also offered their services in this stage of the investigation.
On request of the Dutch Safety Board representatives of the Dutch cabin crew and the pilot associations have taken part in the investigation. As a consequence of this accident nine people were killed, five passengers and four crew members. 86 people were injured.

History of the flight


The Boeing 737-800 of Turkish Airlines departed Istanbul International Ataturk Airport, Turkey for a flight to Amsterdam Airport Schiphol, The Netherlands. The flight crew consisted of three pilots: a line training captain who occupied the left seat, a first officer under line training in the right seat and an additional first officer who occupied the flight deck jump seat.3 The first officer under line training was the pilot flying. As far as known the flight proceeded uneventfully up until approaching the Netherlands.
The aircraft was directed by Air Traffic Control towards runway 18R for an ‘instrument landing system’ (ILS) approach and landing. The crew performed the approach with one of the two autopilot and autothrottle engaged. The standard procedure for runway 18R prescribes that the aircraft is lined up at least 8 NM4 of the runway threshold at an altitude of 2000 feet. 5 Air traffic control is allowed to offer a line
up between 5 and 8 NM of the threshold and instructed the crew in such way that the aircraft lined up at approximately 6 NM at an altitude of 2000 feet. Whether the line up is always performed at 2000 feet, regardless of the distance to the threshold being 5 of 8 NM, is still under investigation. The aircraft descended to 2000 feet above mean sea level6 (amsl) and was vectored towards the localiser. The landing gear came down and flaps 15 were set. The autothrottle system receives information about the altitude from the left radio altimeter during approach and landing. The recorded values on the digital flight data recorder was 8191 feet (this is the maximal value of Digital flight data recorder can register) during the most part of the flight. This value is not displayed inside the cockpit. The maximum value shown in the cockpit is 2500 feet. When the aircraft during approach descended below 8191 feet, the recorded value remained fixed at 8191 feet. At approximately 1950 the recorded value suddenly changed to -8 feet and remained at that value up until shortly before impact. According to the data recorded at the cockpit voice recorder several aural gear warnings sounded (e.g. change landing gear configuration, flaps not selected) when the aircraft was already in Dutch airspace. This warning has to alert the crew that the landing configuration needs to be adapted to the stage of the flight, in this case the landing. The first time the warning sounded was when the aircraft was still at high altitude above Flevoland. Later, during the approach the aural warnings again sounded for several times. The warnings were given because the computer systems receive their data from the left radio altimeter, amongst others, erroneously registered that the aircraft was in the stage shortly before landing. With the aircraft still above Flevoland there was no reason to select the landing configuration and when the aural warnings sounded during the approach, the landing configuration was completely according to the stage of the flight at that time. The cause of the aural warnings and the reaction of the crew to these warnings are still being investigated. The values of the right radio altimeter and pressure altimeter were correct during approach.
The final approach speed of the aircraft was approximately 144 knots.7 At the onset of the descent to the glide scope the speed had increased to approximately 160 knots. According to radar data the localizer of the instrument landing system was intercepted at approximately 5,5 NM from the runway threshold. The standard procedure is that the glide path is approached from below. Because of the shorter line up for the runway at 2000 feet the glide path had to be approached from above. Once the localizer was intercepted
the crew selected, by means of the vertical speed modus of the automatic pilot, a descent speed of 1400 feet per minute to catch the glide path. The autothrottle system entered the retard mode, and the thrust levers were moved to the idle position and remained in retard modus. Normally this mode is automatically engaged during landing flare just prior to touchdown. The glide path was intercepted at approximately 1330 feet and the aircraft was now also at the correct altitude for the approach of runway 18R. The aircraft speed had during the time the aircraft was in vertical speed modus increased to 169 knots, and decreased again when the aircraft followed the glide path. At approximately 900 feet , the flaps were selected to 40 by the crew and the speed continued to decrease. At approximately 770 feet, the crew set the selected airspeed to 144 knots. At that moment the actual airspeed was 144 knots. The autothrottle system should have maintained the speed selected by the crew but, with the thrust levers at idle, speed continued to decay. Because the utomatic pilot wanted to maintain the glide scope, the automatic flight system, in response, commanded increasing nose up pitch and applied nose up stabiliser trim. The stick shakers activated at approximately 460 feet, warning the crew that the angle of attack (AOA)
was too high. The data of the digital flight data recorder show that the thrust levers were immediately advanced but moved back to idle. When the thrust levers returned to idle, the autothrottle was disengaged. Whether these actions were performed by the crew or automatically is still under investigation. At that moment, the speed was approximately 110 knots, the pitch angle was approximately
11° Aircraft Nose Up (ANU) and the recorded AOA was approximately 20°. At 420 feet the autopilot was disengaged by the crew and attempts were made to recover the correct flight position by itching the aircraft. At 310 feet a negative nose position was reached of 8° beneath horizon. Almost simultaneously the thrust levers were advanced to their most forward position after which the aircraft ascended somewhat and the nose position increased.
According to the last recorded data of the digital flight data recorder the aircraft was in a 22° ANU and 10° Left Wing Down (LWD) position at the moment of impact.

Weather conditions

Weather conditions as described in the actual meteorological aerodrome report (METAR), that was issued shortly before the accident were:
• wind 200 degrees with 10 knots;
• visibility 4,500 m in mist; with a forecasted temporary deterioration to 2,500 meter;
• clouds scattered at 700 feet, broken at 800 feet, and overcast at 1000 feet above aerodrome level;
• temperature 4° Celsius and dewpoint temperature 3° Celsius;
• mean sea level pressure was 1027 hPa.

Data from the datarecorders

The aircraft was equipped with a 25 hour digital flight data recorder and a 2 hour cockpit voice recorder. The digital flight data recorder contains over 1,000 parameters. In addition to data from the accident flight data from eight previous flights have been recorded. Data from the digital flight data recorder reveals that both engines responded normally to control inputs during the entire flight. An initial review of flight data indicates that the aircraft responded normally to control inputs throughout the entire approach phase of the flight.
The data recorded by the cockpit voice recorder are of good quality and are still being investigated.

Technical investigation

Accident site
The aircraft impacted farmland 1,5 km north of the Runway 18R threshold. The wreckage trail was approximately 100 m long and along a heading of approximately 160° magnetic. The initial impact ground marks are consistent with the shape of the aft part of the fuselage.
The horizontal stabilizer and both main landing gear legs were separated from the aircraft and located near the initial impact point. The left and right engines had detached from the aircraft and hurled away. The aft fuselage, with vertical stabilizer, was broken circumferentially forward of the aft passenger doors and had sustained significant damage. The fuselage had ruptured at the right side forward of the wings. The forward fuselage section, which contained the cockpit and seat rows 1 to 7, had been significantly disrupted. The rear fuselage section was broken circumferentially around row 28 (the rear-most row of seats on the left-hand side of the aircraft. At the right-hand side at the rear is a row 29). All major items of the aircraft were accounted for, and there was no evidence of in-flight breakup. A significant quantity of fuel was found in both main fuel tanks and there was no evidence of any rupture of the tanks. There was no evidence of an in-flight explosion. There was no sign of fire.

Previous flights
Recorded flight data from the eight previous flights of the aircraft continues to be examined. The data show two other instances of left radio altimeter malfunctions. In the recorded cases, the autothrottle also entered the retard mode above the intended flare altitude, and the thrust levers moved to idle, because of a malfunction of the left radio altimeter. The data of these flights are being investigated.

Autothrottle system
The autothrottle system positions the thrust levers so that the engine thrust is appropriate to system selections made by the flight crew. Thrust levers can be manually repositioned at any time. In this accident the autothrottle system did not maintain the (by the crew) selected speed of 144 knots. This is subject of ongoing investigation.

Radio altimeters
Two low range radio altimeter (LRRA) systems provide height above ground information to various aircraft systems including the instrument displays, autothrottle system, the two automatic pilots and configuration/ground proximity warning system. Each system consists of a transceiver and separate transmit and receive antennas, along with interconnecting coaxial cables. The antennas are mounted on the bottom of the aircraft fuselage. Height above ground is determined by the time taken for a radio signal from the transmit antenna to return to the receive antenna.

The right radio altimeter had provided correct information to, amongst others, the display of the first officer while the left radio altimeter provided a faulty altitude of -8 feet to, amongst others, the captains display. Because this data is particularly used as input for the automatic systems, pilots generally don’t use this information but make use of the information provided by the pressure altimeters, which is prominently positioned at the display, instead. In general pilots only use the information of the radio altimeter shortly before the actual landing of the aircraft in addition to the data from the pressure altimeter.

Survivability factors
The aircraft is fitted with 4 main cabin doors and 4 over-wing exits. Investigators of the Dutch Safety Board found the aircraft with the two right-hand side over-wing exits and the forward left-hand over-wing exit open as well as the two front main cabin doors. None of the evacuation slides were deployed. The vast majority of the seats in the economy class area were still in their seat tracks. The floor in the aft cabin was deformed. Most cabin damage was found in the business class area. There was no evidence of smoke or fire in the cabin.

The door between the cabin and the cockpit was found partly opened. The interior of the cockpit was heavily damaged.

All passengers and crew seats as well as cabin equipment have been registered for further investigation.

Air Traffic Control

Preceding traffic
During final approach the aircraft was preceded by a Boeing 757. For the wake turbulence categories ‘Heavy’ (e.g. Boeing 757) and ‘Medium’ (e.g. Boeing 737) international and national regulations require a minimum separation of 5 NM. According to radar information at the moment the Turkish Airlines Boeing 737 received the approach clearance, the distance between the two aircraft was approximately 6,5 NM. The preceding Boeing 757 was at that moment at approximately 2 NM from runway 18R threshold.

Instrument landing system
The instrument landing system of runway 18R at the time and date of the accident was suitable for CATIII approach as this one was. Data from the Remote Monitoring and Control System indicate a stable operation and no deviations.

Communication
Air traffic control communication with the aircraft did not point at any irregularity on board. The controller on duty at tower West provided landing clearance at approximately 10.25 hrs. Shortly after clearance the aircraft disappeared from radar and he did not see the aircraft on the radar again nor did he not gain sight of it when looking outside in the approach direction. He subsequently sounded alarm. No distress call was received by ATC. The impact area was not visible from the ATC control tower.

Search and rescue

The airport activated the emergency response plan according to procedures. Reports from witnesses enabled emergency services to locate the scene, and rescue operations began. Survivors were transported to nearby medical facilities for treatment after a initial assessment (triage) by medical personnel.

Safety warning

The Dutch Safety Board has issued a warning to Boeing is which extra attention is asked for a part of one of the manuals of the Boeing 737. In this manual is stated that if, preceding flight, the radio altimeters are malfunctioning, the automatic pilots and autothrottle systems cannot be used for approach and landing. De Board has given Boeing into consideration to investigate if these procedure should also be valid during all phases of a flight.
Boeing has issued a Multi Operator Message’ (MOM) the same day concerning the malfunction of the left radio altimeter.

Continuing investigation

The investigation by the Dutch Safety Board continues, with the assistance of the Turkish Directorate General for Civil Aviation, The Dutch Transport and Water Management Inspectorate, The American National Transportation Safety Board, the United Kingdom Air Accident Investigation Branch, the French Bureau d’Enquetes et d’Analyse, Air Traffic Control The Netherlands, the aircraft operator, the aircraft manufacturer, engine manufacturer, component manufacturers and representatives of flight and cabin crew associations. The investigation will examine technical, operational, survivability, ATC procedures, human factors and safety management aspects. Several avionics components, including the LRRA transceivers, autothrottle computers, flight control computers and flight management computers have been removed from the aircraft for further investigation. Furthermore emergency response and post crash anagement will be investigated.

• Back to top