quinta-feira, 18 de agosto de 2016

More Gadgets on Flight Deck for Pilots Being Prepared to the Future


Rockwell Collins está planejando entregar o software final para Boeing para instalá-lo nas telas de cockpit do  737 MAX em meados de Setembro, seguida por entregas iniciais dos componentes finais de hardware no final do ano.

A entrega encerrará os quatro anos de trabalho de design, desenvolvimento e trabalho de testes já feitos, sendo os mais desafiantes pelo objetivo da Boeing de manter a máxima semelhança entre o 737NG e o 737 MAX, em parte para manter o tipo comum classificações entre os dois, e as mínimas “diferenças de treinamento" para os pilotos. A Boeing está planejando para  2017 as primeiras entregas do replanejado e de outra forma modernizado 737, para o qual ela reuniu mais de 3200 pedidos.

"Uma das coisas que tem sido um desafio para nós e para a Boeing é que estamos pegando um sistema de telas de 2015 e o aplicando em um avião que foi projetado em 1964 e que não mudou tanto assim em termos de sistema hidráulico, elétrico e de ar condicionado", diz Keith Stover, engenheiro-chefe do programa MAX da Rockwell Collins. "Nós estávamos tentando encaixar este novo sistema nele e fornecer recursos que não existem na aeronave atual."

O que resultou é indiscutivelmente o melhor dos dois mundos, com o cockpit imitando os 737NGs, enquanto permitindo que para certos recursos avançados, tais como a capacidade de tela dividida, mas com a flexibilidade e poder de processamento para introduzir mais recursos avançados no futuro, incluindo Transmissão de Vigilância Dependente Automática - ADSB "DENTRO" das aplicações de vigilância.

O cockpit do Boeing  MAX apresenta quatro grandes telas nos formatos 15,1 polegadas dispostas lado a lado em todo o painel, substituindo seis telas construídas pela Honeywell de 8 X 8 polegadas exibidas em uma disposição de "T" nos modelos de Boeing NG. O hardware Rockwell Collins inclui as quatro telas, dois computadores de processamento localizados no alojamento de eletrônicos e novos painéis de interruptores no console central.

As telas são as versões de terceira geração das telas de grande formato que Rockwell Collins desenvolveu para o Boeing 787. A fabricante está usando a tela de segunda geração no cockpit do avião-tanque aéreo KC-46 Pegasus da Força Aérea. As diferenças entre a primeira e a terceira geração incluem a introdução de novos LEDs e LCDs, uma redução na profundidade do monitor para 8,9 centímetros nos monitores de 20 centímetros e uma diminuição no peso para 4,8 Kg nos de 7.1 Kg. Uma vez certificados, Stover diz, a tela de monitor dos Boeings MAX será adaptável para o Boeing 787.


quinta-feira, 4 de agosto de 2016

In-Flight Fire - Batteries Travelling in Passenger Baggage





Halon replacement deadlines

In 2010, the European Commission adopted cutoff and end dates for essential-use exemptions for halon on airplanes operating in the European Union. The International Civil Aviation Organization adopted halon replacement deadlines in 2011, and Underwriters Laboratories will withdraw its standard for halon in handheld fire extinguishers in 2014.

Aggressively Pursue 
Aggressively pursuing a fire means taking immediate action to determine the source of hot spots, smoke, and/or flames. The crew should quickly evaluate the situation, gain access to the fire, and attack the fire using all available resources, which may include deadheading crewmembers or able-bodied persons (ABP).

Cheek Area
This term describes the area just below the floor, outboard of the cargo compartment areas. In narrow and widebody aircraft, this area houses wire bundles, hydraulic lines, and other electrical components. (See Appendix 2, Typical Widebody Cross-Section.) c. Circuit Breaker. Circuit breakers are designed to open an electrical circuit automatically at a predetermined overload of current. d. 

Halon 
Halon is a liquefied gas that extinguishes fires by chemically interrupting a fire’s combustion chain reaction, rather than physically smothering it. This characteristic is one of the main reasons that halon extinguishers are effective when the exact source of the fire cannot be positively determined. Halon fire extinguishing agents that have been approved for use in aircraft include Halon 1211, Halon 1301, and a combination of the two (Halon 1211/1301). Both are typified as “clean agents,” leaving no agent residue after discharge. Approved halon-type extinguishers are three times as effective as carbon dioxide (CO2) extinguishers with the same weight of extinguishing agent.

Insulation blanket burn-through protection
Fire-protective insulation blankets are designed to resist burn-through from a fuel fire next to the bottom half of the fuselage

Photoelectric-area type. These detectors are designed to detect the presence of smoke particles in the air by reflection of scattered light. They also rely on particles in the air being convectively carried into a sensing chamber where light from a pilot lamp is transmitted through a sensing chamber. If smoke is present, it will reflect light onto a photocell and trigger an alarm. Newer production airplanes use photoelectric detectors based on an advanced smoke sensor utilizing two discrete wavelengths to determine the presence of smoke and to distinguish between smoke and nonsmoke aerosols. These are also mounted in the ceiling or upper sidewalls of the protected space.

Photoelectric-ducted type. These detectors are similar to photoelectric-area type detectors, but they are typically mounted behind the walls of the protected space. They differ from the area detectors in that fans draw air samples from the protected space into a series of air sampling ports in the monument walls and ceiling, and then through an aluminum tube manifold to the detectors. Current production airplanes use the more advanced area detectors mentioned above, rather than ducted photoelectric detectors.
Each smoke detection system has a built-in electronic test capability switch. This allows for the system’s electrical and detector sensor integrity to be checked at any time.
Detection of smoke is affected by compartment volume and contour, air distribution, and the amount and buoyancy of the combustion particles. Boeing conducts extensive laboratory and flight testing to determine the best location for the detector sensors to enable them to most effectively detect smoke under all conditions.

One of the largest trends in the growth of in-flight fire is due to the transportation of lithium batteries. From March 1991 to October 2012, the FAA office of Security and Hazardous Materials Safety recorded 132 cases of aviation incidents involving smoke, fire, extreme heat or explosion involving batteries and battery powered devices (Federal Aviation Administration, 2012). Lithium batteries were the majority of battery types in the incidents. (Levin, 2011)

Lithium ion batteries (Li-ion) are used to power portable electronic devices such as cellular phones, portable tablets, EFBs and digital cameras; Li-ion batteries are rechargeable. Non-rechargeable lithium batteries (Li-metal) are similar to Li-ion, but use a different electrode material – metallic lithium.

All lithium batteries present a potential fire hazard. These batteries are carried on aeroplanes as cargo, within passenger baggage, and by passengers directly. Like some other batteries lithium batteries are capable of delivering sufficient energy to start an in-flight fire (Kolly). Lithium batteries present a greater risk of an in-flight fire than some other battery types because they are also unable to contain their own energy in the event of a catastrophic failure (Kolly).

Only a small fire source is needed to start a lithium battery fire. The material around lithium battery powered devices (often plastic) melts easily and ignites adjacent cells or batteries, contributing to higher fire intensity (Webster, 2004). When shipped as cargo, batteries are packed on pallets.
Aviation accidents and incidents, believed to be caused by Li-ion battery initiated fire, have occurred when battery shipments were placed next to other cargo on the aeroplane. On 3 September 2010, UPS Flight 006, a cargo flight from Dubai, United Arab Emirates, to Cologne, Germany, crashed off airport near Dubai resulting in the deaths of the two crewmembers. The Boeing 747-400F departed Dubai but returned due to smoke in the cockpit and the indication of major fire on the main deck.

The investigation revealed that a large quantity of lithium batteries were on the flight.
Following the accident the FAA issued a SAFO stating that Halon was inefficient in fighting fires involving a large quantity of lithium batteries. A restriction was also put in place to restrict the carriage of lithium batteries carried in bulk as cargo on passenger flights. (Federal Aviation Administration, 2010)

Additionally, IATA modified the Dangerous Goods Regulations to improve risk reduction for the shipment of lithium batteries. (International Air Transport Association IATA, 2012).

Batteries travelling in passenger baggage can also start an in-flight fire. The FAA recommends that lithium batteries should not be packed in checked luggage, but kept in hand luggage and stowed in overhead aeroplane’s compartments during flight. On 17 April 2012, an in-flight battery fire incident occurred on Pinnacle Flight 4290 from Toronto, Canada to Minneapolis/Saint Paul, Minnesota (LitBat Fire TransCanada October 2011). While at 28,000ft, a passenger’s personal electronic device (an air purifier) caught fire.

During the in-flight service, the flight attendant noted that the device was on fire on the floor; its battery was burning several feet from the device. Using water from the  service cart, the flight attendant put out the fire using wet paper towels. She then submerged the battery in a cup of water because the battery was still smouldering.
On the flight deck, the Captain sensed very strong burning electrical odour coming from the cabin. An emergency was declared and the flight diverted and landed safety at Traverse City, Michigan (Avherald). Li-Ion batteries such as the one described in the incident above do not need to be operating in an active circuit to catch fire and do not require a short to overheat. Incidents like this one are becoming more common as the number of personal electronic devices increase as shown in the FAA office of Security and Hazardous Materials Safety data. It is not uncommon for a passenger to carry several devices with lithium batteries.

Devices include, but are not limited to, laptop computers, tablet computers, mobile phones, electronic watches, flashlights, EFBs, and e-readers.
On a typical flight, a single aisle jet carrying 100 passengers could have over 500 lithium batteries on board. These devices are not tested or certified nor are they necessarily maintained to manufacture’s recommendations. Replacement batteries from questionable sources (‘grey’ market) can be contained within devices.

‘Grey’ market batteries may not be manufactured in accordance with international standards. It is possible that they have a greater probability than original equipment to overheat and cause a fire. Aircraft crew have no means to determine the presence of ‘grey’ market batteries or the physical condition of batteries on board.
The FAA Fire Safety Branch through cooperation with the International Aircraft Systems Fire Protection Working Group conducted several tests using standard Lithium-Ion batteries.
The tests used a standard air exchange rate of one cabin air exchange every 60 seconds using one air conditioning pack (system) with the gasper fans operating; the flight deck door was closed for all tests. The results for the first test showed that there was no visible smoke or audible warning prior to the battery event. After the battery went into thermal runaway the smoke percentage was greater than 10% light obscuration per foot for a period of approximately 90 seconds (Summer, 2012). The second test performed outlined similar results. In conclusion, the outcome of the tests prove that even in a high ventilation rate a typical COTS Li-Ion battery could pose a “significant hazard within the flight deck environment and could potentially present a catastrophic risk” (Summer, 2012).



 Lavatory fire protection

Lavatories include systems to both detect and extinguish fires

One type of electronic device that is rapidly gaining use in all forms of aviation is the EFB. These devices are used by pilots to replace paper materials found inside the flight deck. EFBs can be divided into groups by Classes:

·         Class I: Portable electronic devices (PEDs), Commercial off the shelfequipment (COTS), used as loose equipment and stowed during portions of flight.
·         Class II: PED can be COTS equipment, mounted and connected via aeroplane power supply for use in flight and for charging.
·         Class III: Not PEDs or COTS. Class 3 is considered installed aeroplane equipment. These are built and tested specifically for aeroplane EFB use (Summer, 2012) Class I and II are not subject to FAA airworthiness standards. However, Class II mounting and charging connections are. Class III is subject to airworthiness standards for all aspects of their operation. Because Class I and II are not subject to FAA airworthiness standards, they bring potential hazards when used as EFBs. All classes of EFBs utilize lithium-ion batteries as their primary power source.

As the number of Class I and II devices increase in their use inside the flight deck, the number of potential hazards also increases.

The FAA Technical Center conducted research on all classes of EFBs. They cited the primary concern as thermal runway of lithium batteries.

“The primary concern is the resulting fire/smoke hazards should one of the lithium-ion (Li-ion) batteries installed in these units fail and experience thermal runaway, a failure causing rapid increases in temperature, significant smoke production and at times, explosion and/or rocketing of the battery cell.”

Furthermore, the FAA tests found that:

The testing showed that even with a very high ventilation rate of one air exchange per minute within the cockpit, a typical COTS Li-ion battery could pose a significant smoke hazard within the flight deck environment. . The initial battery event occurred, at times, without warning (i.e. no visible smoke or audible event prior to failure). The battery cells failed in a very vigorous manner, at one point with enough pressure to forcefully push open the unlatched cockpit door. The most striking safety hazard however, was the volume and density of smoke that emanated from the failed battery cells.
During one test in which only four of the nine battery cells went into thermal runaway, the installed smoke meter recorded greater than 10% light obscuration/ft for a period of greater than 5 minutes and a peak value of greater than 50% light obscuration/ft, resulting in severe lack of visibility within the flight deck. (Federal Aviation Administration, 2012)

As portable electronic devices become more powerful, so will their batteries. The increasing energy densities of the batteries will also increase the likelihood of producing an uncontrollable in-flight fire. The proliferation of portable electronic devices will also increase the risk of battery failure incidents (Keegan, 2001).


Technologies are available to lessen the spread of lithium battery-fuelled fires. The FAA has requested that ISO develop a standard for Fire Containment Covers. They have also conducted testing of intumescent paint, which acts as a thermal barrier, when used in the packaging of lithium batteries. (Pennetta, 2012).

Ceiling-mounted smoke detectors
Typical faceplate of a ceiling-mounted ionization smoke detector (left) and a photoelectric smoke detector (right)

sábado, 11 de junho de 2016

Why no PTLU on Airbus 340-500/600 or Reason for a PTLU on Airbus 330/340


Yaw Maneuver Criteria

• “Sudden Pedal Input till pedal stop” (one way) must be structurally possible from VMCA to VD



• “Sudden pedal release from full pedal input” once in steady side slip state, must be structurally possible from VMCA to VD.



Yaw Maneuver Criteria

• In case of an engine failure, the pedal deflection required for the corrective action from the pilot after 2 sec recognition time must be possible.




Loads and Rudder Travel Limitation Unit

• In other words, the structure and the load limits are dimensioned so as to match the yaw maneuver criteria with adequate rudder deflection limited by a judicious RTLU.



• However, the RTLU is not designed to protect the Rudder Structure for any “unrealistic” action of the pilot on the rudder pedals.



• Finally, the Certification Criteria do not address “all” possible asymmetry cases for load considerations (typically 2 same side engine out configuration on a quad, sharp roll maneuvers with rudder deflected …)



Typical Cases including high loads

• Engine failure case:

If, once the pilot has centered the ß target, he then commands a sharp turn unto the live engine, the side slip increases rapidly.

Thus the Yaw Damper abruptly reacts, which induces high loads.



Typical Cases including high loads

• Engine failure case

– Be aware that there is no restriction to roll the aircraft with an engine failure (no additional rudder input required)



– Furthermore with an engine failed, the maximum roll rate is limited to 7.5 o / sec (on FBW A/C at low speed, typically 160 knots).



– At VMCA and V2 min, the certification requires to demonstrate adequate roll capability, with full roll input; the maximum ß reached is around 10 o and loads are Ok.



Reason for a PTLU on A330/A340

• The “Yaw Damper” has a great authority in terms of rudder deflection and rudder deflection rate, on A330/A340 as compared to A310/A320.



• Thus, in case of a steady state side slip maneuver, the Yaw Damper decreases the initial rudder deflection so as to minimize the Side Slip.



• The PTLU is the Pedal Travel Limit Unit which limits the pedal deflection as a function of the A/C CAS.


Reason for a PTLU on A330/A340

When the pilot releases the rudder pedals suddenly to neutral, as requested by certification criteria, a peak of high loads can be reached (since the rudder pedal release is equivalent to a mechanical rudder movement of same amplitude) leading to a rudder deflection on opposite side.


Why no PTLU on A340-500/600
• The rudder channel is fully electric on the A3456

• Thus the rudder pedal directly commands the amount of rudder as a function of the IAS and pedal deflection

• At a given IAS, the rudder pedals are able to command a maximum rudder deflection, as per TLU. Any additional pedal input has no effect on the rudder (PTLU and RTLU built in the lateral law).


terça-feira, 19 de janeiro de 2016

Citation XLS+ PR-AFA - Holding Pattern Entry Is NOT Mandatory


SCROLL DOWN FOR ENGLISH TEXT

AVIAÇÃO NO SÉCULO XXI

Os recursos instalados nas modernas aeronaves estão lá no cockpit como complemento para a segurança da NAVEGAÇÃO AÉREA. Esta minha afirmação é por demais, verdadeira, pois está escrito em TODOS os manuais de operação de todas as aeronaves neste planeta, que “no evento de falha dos instrumentos “SOFISTICADOS”, o piloto somente DEVE confiar nos simplíssimos instrumentos BÁSICOS”:

1.    Bússola

2.    Velocímetro

3.    Altímetro

A aeronave mais moderna do planeta possui OBRIGATORIAMENTE esses instrumentos acima no seu painel sofisticado, e isso para ser usado no evento de falha total na sofisticação.

Teoricamente um piloto detentor de certificações em determinada aeronave, está apto para conduzir uma aeronave de grande porte que eventualmente tenha ficado com apenas os 3 (três) instrumentos acima funcionando,  a pousar em um aeroporto nas proximidades do evento da emergência.

É mera especulação dos investigadores do CENIPA, órgão da Força Aérea Brasileira, encarregado de executar as investigações de acidentes aéreos. As conclusões são medíocres. As alusões são insidiosas. Muita falácia militar.

A avaliação dos investigadores beira a IRRACIONALIDADE quando aventam que a voz do piloto comandante da aeronave no voo produziu indícios de ESTAFA.

Ora, qualquer piloto não emitirá um timbre de voz de CONTENTAMENTO ao iniciar um Procedimento de Arremetida. A sensação é recalcitrante, é de desperdício de tempo, combustível e insatisfação pelo objetivo não cumprido.

O traçado dos perfis de procedimento de aproximação de voo para pouso por instrumentos é MANDATÓRIO para aquelas aeronaves e tripulação que estão limitadas aos parâmetros aquém da era contemporânea de auxílios à navegação aérea.

O “atalho” tão condenado pelos investigadores do CENIPA é um recurso LEGAL e LÓGICO, além de sua utilização por tripulação INTELIGENTE.

Para o familiar de vítima de acidente aéreo quando um investigador PLANTA a notícia de que houve um ATALHO, esse familiar LEIGO em aviação pensará de imediato que foi feito algo ILÍCITO, quando na realidade foi executada uma manobra LÓGICA e fundamentada nos recursos instrumentais de altíssima performance no auxílio para os pilotos assegurarem o pouso com máxima segurança.

Pilotos de aeronave,  tais como do avião Cessna Citation XLS+ 560-6066, matrícula PR-AFA, não devem ficar restritos à utilização BÁSICA dos instrumentos. Esse instrumental sofisticado é para ser DOMINADO pelo tripulante em todas as fases do voo.  

O que se depreende da ALUSÃO dos investigadores para a decisão do Pilot-Flying (PIC) é que todo o esforço dos engenheiros de Software para navegação aérea, tal ‘coletânea de recursos moderníssimos e precisos’ de navegação horizontal e vertical, seja abandonada e os pilotos fiquem escravizados pelas sugestões dos NÃO FAMILIARIZADOS investigadores de acidentes aéreos com a prática, os quais estão apenas deduzindo a partir dos manuais.

Os investigadores do CENIPA querem a todo custo incutir na mente de brasileiros LEIGOS em aviação, um estado mental de brasileiros CULPAREM os pilotos por terem sido extremamente LÓGICOS e usarem o recurso adequadamente, e por que não dizer, brilhantemente. Esses mesmos investigadores portam-se com total incoerência, pois afirmam que o objetivo da investigação NÃO é apontar culpados e responsabilidades, mas intrinsicamente eles APONTAM com todas as letras e INSÍDIA, que o procedimento do piloto em eliminar algumas fases do procedimento de aproximação por instrumentos, chamado vulgarmente de ‘atalho’, seria uma falta de cumprimento de normas. E até mesmo o Procurador da República, Thiago Lacerda Nobre, aventa de que houve violação de regras de tráfego aéreo.

JAMAIS, tão alusão tem valor jurídico ou técnico operacional, quer partindo dos investigadores quer do Procurador ou Promotor Público. Não existe na regulamentação qualquer alusão de que um piloto de aeronave possuidora de recursos de última geração para navegação aérea NÃO poderá eliminar certas etapas do Procedimento de Aproximação para Pouso por Instrumentos.

Afirmo ainda que cientificamente, as etapas do voo desde o instante do desvio para a esquerda, descendo sobre o mar até a altitude de 2200 pés e voando depois no prolongamento do eixo da pista até o instante da declaração do piloto acerca de efetivar a arremetida, tenha prejudicado a lógica do voo ou sua segurança. Muito pelo contrário, pois as várias curvas que foram evitadas ao eliminar certas etapas, elas sim, tinham o potencial de desorientar espacialmente os tripulantes.

O acidente em nada se relaciona à fase chamada INSIDIOSAMENTE de ‘atalho’, pois a aeronave foi conduzida até o ponto da arremetida sem aparentes problemas. O que ocorreu causando fatalidade, está física e temporalmente associado ao percurso após a arremetida, e muito mais precisamente, após o anúncio verbalizado do comandante da aeronave de que ele estava iniciando uma ARREMETIDA.

Não existe uma única razão para esses investigadores aventarem que o tão propalado ‘atalho’ esteve relacionado com a falta de controle aerodinâmico da aeronave.

ENGLISH

XXI CENTURY AVIATION


The high-tech instruments installed on modern aircraft are there on the ‘flight deck’  in addition to the safety of air navigation. This statement is entirely true, since it is written in all flight crew operation manuals on this planet, that "in the event of all sophisticated instruments failure”, the pilot only must rely on the simplest basic instruments" listed below:


1.         Compass


2.         Aerodynamic Speed Indicator


3.         Altimeter


The most modern aircraft on the planet COMPULSORILY has installed these instruments listed above in its sophisticated panel, and that to be used in the event of total failure on high-tech instrumental.


Theoretically, a pilot holding his/her certifications for given aircraft, he/she is fit to pilot a large aircraft that eventually got only those above three working instruments, and he/she is capable of landing at an airport in vicinity of emergency point.


It is mere speculation of CENIPA’s officials, which is a military unit of the Brazilian Air Force, responsible for carrying out the investigations of air accidents. Mediocre investigation conclusions. Insidious concepts to the pilots. Military fallacy as own marketing.


The assessment of investigators edges irrationality as they presume the co-pilot voice radio transmitted during that flight had produced evidence of fatigue. That is very funny if it weren’t so tragic.


Let’s think seriously, any pilot on this planet will not emit a happy voice tone just after he/she has started a Go-Around Procedure. The feeling is recalcitrant, for waste of time and waste of fuel, and dissatisfaction by unmet goal.


The drawing of the instruments landing approach flight procedure profiles is COMPULSORY for better understanding by  the flight crew but  that strokes are limited to short of the modern era of air navigation aid.


The "shortcut" as doomed by CENIPA’s investigators is a LEGAL and LOGICAL procedure, in addition to its use by smart flight crew.


As a relative of an aircraft accident fatal victim hears some news from an investigator that there was a flight “shortcut”, that relative, which is a LAYMAN in aviation immediately will imagine something illicit has been done by the pilots, when in reality, it was performed a LEGAL maneuver within flight LOGIC based on high-tech instrumental resources on board further helping to ensure pilots landing with maximum safety.


Pilots of aircraft such as Cessna Citation XLS+ 560-6066, registration PR-AFA, should not be restricted to the basic use of the standard instruments. That sophisticated instrumental, highly precise, is to be DOMINATED and put it in good practice by the crew in all phases of flight.


What we can see from the investigators reference to the Pilot-Flying (PIC) decision on eliminate some phases depicted on the Instruments Approach Landing Chart is that all endeavors by Software engineers in navigation, such as  ' high-end resource software routines for accurate horizontal and vertical air navigation should be given up and the pilots stood enslaved by the mind of the air accident investigator guesser. As a general rule, a person not familiar with the operation of those flight high-tech instruments.


CENIPA’s investigators want at all costs to instill in Brazilian LAYMEN mind a feeling state that all Brazilians must BLAME the pilots. The Brazilian air crash investigators NEVER point their fingers to the manufacturer, even though there is a roll of evidence of manufacturer failure.


The Flight Crew Operation Manual for this plane brings some remarks to the pilots about the plane misbehavior after go-around procedure or even during a take-off as the plane speeds up to 215 (± 10) KIAS and the Flaps lever is out of ZERO position. A speed sensor for stabilizer signals to a logic circuitry to freeze the stabilizer on NOSE DOWN position till the speed to be decreased below 200 Knots. The flaps must NOT be retracted during this speed of 215 (± 10) KIAS.

The issue is the alert for calling flight crew attention but it only occurs very later. When the current alerts come on the MFDU, the Stabilizer is AUTOMATICALLY already frozen  on NOSE DOWN pitch setting. The aircraft nose instantaneously and abruptly, in milliseconds, falls down without any chance for the flight crew to raise the aircraft nose as in very low altitude, mainly on the MDA altitude. Unfortunately, the aircraft will get into the terrain almost vertically in vicinity upon very high speed.

In my opinion, the aircraft manufacturer MUST install another alert (aural) like those on EGPWS, to alert the flight crew as soon as the speed reaches  215 (± 10) KIAS, and the flaps lever is out of retracted position (0° FLAPS), and the landing gears aren’t fully retracted (INTRANSIT light ON).

The aural alert I supposed it could be like that:

SPEED …STABILIZER…SPEED…STABILIZER…SPEED …STABILIZER

That will alert the flight crew to immediately decrease the airplane speed to 200 Knots.

The pilot in command was extremely logical and he used the resource on board properly, and why not say, brilliant.

These same CENIPA’s investigators behave in complete incoherence, since they claim that the purpose of their investigation is not pointing fingers to anyone or announce responsibilities, but intrinsically they point out with all the Final Report letters and their WILL, that pilot procedure in eliminating some stages of the instrument approach procedure, said by them a 'shortcut', would be a lack of compliance to the air traffic rules. And even the State Prosecutor, Thiago Lacerda Nobre, suggested to the Press there was violation of air traffic rules. He doesn’t know Air Traffic Rules so deeply to state that. All of them in this case are guessers.

NEVER such allusion will have legal or technical value, neither CENIPA’s investigators nor the Prosecutor or District Attorney are well-founded to state that. There is no mention of flight rules forbidding a pilot flying with next-generation capabilities for air navigation to eliminate certain steps of the Flight Approach profile, providing that he/she keeps restraining the plane above minimum altitudes as flying over sea. That is not intended for flight over obstacles.

Scientifically, the flight stages from the moment of the detour to the left, going down over the sea up to the altitude of 2200 feet and after flying along the extension of the runway centerline till the moment Pilot-Flying’s  announcement  for go-around, there was no any  undermined logic or encroach to the air traffic rules. On the contrary, various turns avoided by eliminating certain stages (for those turns had potential to disorient spatially the crewmembers), the plane flew without issues till the go-around beginning.

LOGICAL CONCLUSION.

The accident in nothing relates to the phase called INSIDIOUSLY of ' shortcut ', because the aircraft was flown to the go-around point (MAPt) without apparent issues. What have occurred causing fatality, is physically and temporally associated with the route flown just after the go-around, and more precisely, following the Pilot announcement verbalizing he is starting the go-around. The investigation only should  have concerns after the pilot has stated “I will wait for better weather”, that meaning he would fly the plane ascending to 4000 feet heading 375 NDB SAT, and keep flying on holding pattern, nothing more than that.
A seguir está um exemplo do que ocorreu comigo:





A atitude de um piloto decidir por eliminar a entrada em órbita e até mesmo eliminar a fase de afastamento, optando por voar direto para um ponto de interceptação na reta final da pista de pouso em uso é LÓGICO e perfeitamente aceitável e não estará o piloto infringindo a regulamentação.


E para provar a eficiência desse recurso utilizando os computadores de bordo, eu executei tal procedimento com total sucesso em Saint Croix, Ilhas Virgens Americanas, no Caribe.


Decolei de Fort Lauderdale à noite e ao chegar em Saint Croix o mundo estava desabando com chuva.


Desde a minha descida do nível de cruzeiro programei o FMS para interceptar a reta final sobre o mar caribenho, criando o ponto de interceptação (PBD) adiante da órbita, assim eliminei todas as curvas desnecessárias do procedimento de entrada em órbita. Prossegui na aproximação final e quando percebi que não havia iluminação de pista, não hesitei, continuei para o pouso e pousei suavemente. Taxiei para o pátio de estacionamento e tivemos que ficar dentro da aeronave por mais de 90 minutos devido à forte chuva.


É para isso que servem os recursos de bordo.



IPSIS LITTERIS

(FLYING TRAINING, Instrument Flying, USAF, by colonel E. J. BAKER)



g. Restrictions. The procedure turn will not be flown in the following instances:

(1) When issued an ATC clearance for a "straight-in" approach.

(2) When the initial approach is via a no procedure turn required (NoPT) course.

(3) When ATC radar vectors the aircraft to final approach course.

(4) When established in a published or assigned holding pattern, subsequently cleared for approaching and the following two conditions are met:

(a)    The holding course and procedure turn course are the same.

(b)   The aircraft is on the maneuvering side of the procedure turn.

(5) When conducting "timed approaches" from a holding fix. Timed approaches are in progress when you are established in a holding pattern and given a time to depart the FAF inbound.



NOTE: In any of the situations in g above, proceed over the FAF at the published altitude and continue inbound on the final approach course without making a procedure turn, holding pattern, or any other aligning maneuver before the FAF unless otherwise cleared by ATC. When cleared for the approach in any of the above situations, if the pilot desires to fly the procedure turn or to make additional circuits in a published or assigned holding pattern to lose excessive altitude or to become better established on course before departing the FAP, it is his or her responsibility to request such maneuvering from ATC.



No caso em estudo Cessna Ciatation XLS+ 560-6066 (PR-AFA), em virtude da não existência de Controle de Tráfego Aéreo para pouso na pista da Base Aérea de Santos, o piloto em comando apenas deveria declarar a intenção de interceptar a reta da aproximação final, informando a distância em milhas náuticas e a altitude deste ponto de interceptação (mesma altitude do final da curva de afastamento) até a cabeceira da pista.

 Exemplo:

“Rádio Santos, PAPA, ROMEU, ALPHA, FOXTROT, ALPHA, chamará estabilizado no curso da aproximação final, 10 NM, 2200 pés, por NAVEGAÇÃO PRÓPRIA”.

Esta declaração por si, já significa que tanto o bloqueio, entrada em órbita (holding) quanto o afastamento estão eliminados.



terça-feira, 29 de dezembro de 2015

Crash Flight QZ8501 Under Individual or Collective Maintenance Responsibility



On 28 December 2014, an Airbus A320-216 aircraft registered as PK-AXC was being operated by PT. Indonesia Air Asia on a scheduled flight from Juanda International Airport Surabaya, Indonesia to Changi International Airport, Singapore. The aircraft departed at 0535 LT (2235 UTC, 27 December 2014) and was cruising at 32,000 feet (FL320) via ATS (Air Traffic Services) route Mike 635 (M635) with total occupants of 162 persons. The Pilot in Command (PIC) acted as Pilot Monitoring (PM) and the Second in Command (SIC) acted as Pilot Flying (PF).

Em 28 de dezembro de 2014, uma aeronave Airbus A320-216 registrada como PK-AXC estava sendo operada pela empresa privada Indonesia Air Asia num voo regular a partir do Aeroporto Internacional de Juanda, Surubaya, Indonésia para o aeroporto Internacional de Changi, Singapore. A aeronave partiu às 05:35 Local Time (22:35 UTC, em 27 DEZ 2014) e estava cruzando a 32.000 pés (Flight Level 320) na rota ATS (Serviços de Tráfego Aéreo) Mike 635 (M635) com o total de 162 pessoas a bordo. O Piloto em Comando (PIC) atuava como Pilot Monitoring (PM) e o Segundo Piloto em Comando (SIC) atuava como Pilot Flying (PF).
The totals of 162 persons were on board this flight consisted of two pilots, four flight attendants and 156 passengers including one company engineer.
O total de 162 pessoas que estavam a bordo deste voo consistia de dois pilotos e quatro comissários de bordo e 156 passageiros, incluindo um engenheiro de empresa.
The sequence of events was retrieved from both of Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR).
A sequência de eventos foi recuperada de ambos os gravadores, Flight Data Recorder (FDR) e  Cockpit Voice  Recorder (CVR).



The way pilots responded to a technical malfunction resulted in the crash of Air Asia Flight QZ8501, investigators said Tuesday [DEC 29, 2015]. The ill-fated plane was en route to Singapore from the Indonesian city of Surabaya on December 28 last year when it crashed into the Java Sea, killing all 162 people on board.

A maneira que os pilotos responderam a um mau funcionamento técnico resultou no acidente da Air Asia Voo QZ8501, os investigadores disseram na Terça-feira [29 DEZ 2015]. O malfadado avião estava em rota para Singapura a partir da cidade Indonésia de Surabaia, em 28 de Dezembro no ano passado quando ele caiu no Mar de Java, matando todas as 162 pessoas a bordo.
The plane’s flight control computer had a cracked solder joint that kept malfunctioning. Aircraft maintenance records found it had malfunctioned 23 times in the year before the crash, and the interval of those became shorter in the three months prior to the crash.
“Subsequent flight crew action resulted in inability to control the aircraft… causing the aircraft to depart from the normal flight envelope and enter a prolonged stall condition that was beyond the capability of the flight crew to recover,” Indonesia’s National Transport Safety Committee said in a report.

O computador de controle de voo do avião que o mantinha funcionando teve uma junta de solda rachada. Nos registros da manutenção da aeronave descobriu-se que ela [aeronave] tinha sofrido mau funcionamento 23 vezes no ano antes do acidente, e o intervalo desses maus funcionamentos tornou-se mais curto nos três meses antes do acidente. "A ação subsequente da  tripulação de voo resultou na incapacidade de controlar a aeronave... causando à aeronave afastar-se do envelope de voo normal e entrar em uma condição prolongada de estol que foi além da capacidade da tripulação de voo para recuperar [o voo normal]," O Comitê Nacional de Segurança de Transporte da Indonésia disse em um relatório.


The investigation concluded that contributing factors to this accident were:
·      
A investigação concluiu que os fatores contribuintes para este acidente foram:
·         The cracking of a solder joint of both channel A and B resulted in loss of electrical continuity and led to RTLU failure.
·         A quebra de uma junta de solda de ambos os canais, A e B, resultado da perda de continuidade elétrica e que conduziu à falha da RTLU. [Rudder Travel Limiter Unit = Unidade Limitadora do Percurso do Leme].
·         The existing maintenance data analysis led to unresolved repetitive faults occurring with shorter intervals. The same fault occurred 4 times during the flight.

·         A análise de dados de manutenção existentes conduziu para as falhas repetitivas não solucionadas ocorrendo em intervalos mais curtos. A mesma falha ocorreu 4 vezes durante o voo.
·         The flight crew action to the first 3 faults in accordance with the ECAM messages. Following the fourth fault, the FDR recorded different signatures that were similar to the FAC CB‟s being reset resulting in electrical interruption to the FAC‟s.
·         A ação da tripulação de voo para as 3 primeiras falhas em conformidade com as mensagens do ECAM [Electronic Centralized Aircraft Monitoring]. Após a quarta falha, o FDR [Flight Data Recorder] gravou sinais diferentes que eram semelhantes aos [sinais] do  FAC CB‟s [Flight Augmentation Computer circuit brakes = fusíveis elétricos] reposicionados resultando em interrupção elétrica para os FAC‟s.
·         The electrical interruption to the FAC caused the autopilot to disengage and the flight control logic to change from Normal Law to Alternate Law, the rudder deflecting 2° to the left resulting the aircraft rolling up to 54° angle of bank.
·         A interrupção elétrica do FAC causou ao piloto automático desengajar e à lógica de controle de voo para mudar de Normal Law para Alternate Law, [e  ainda causou] a deflexão do leme 2° para a esquerda, resultando a aeronave rolar até o ângulo de 54° de inclinação lateral.
·         Subsequent flight crew action leading to inability to control the aircraft in the Alternate Law resulted in the aircraft departing from the normal flight envelope and entering prolonged stall condition that was beyond the capability of the flight crew to recover.

·         A ação subsequente da tripulação de voo conduziu à incapacidade para controlar a aeronave [no modo] Alternate Law o que resultou na aeronave saindo do envelope de voo Normal e entrando na condição  prolongada de stall que foi além da capacidade da tripulação de voo para recuperar.


RUDDER and YAW DAMPER

RUDDER and LOADS



CONSIDERATIONS



• The rudder deflection is the sum of:

– the order from the pedal input

– the order from the “Yaw Damper” function.

• This deflection is limited by the RTLU (Rudder Travel Limit Unit) for structural considerations.

• The Rudder trim merely moves the pedals.



Role of the “Yaw Damper” on FBW aircraft: A320



• The “Yaw Damper functions are achieved by the ELAC when handflying the Aircraft:

– Dutch Roll Damping and Turn Coordination

– Lateral Control Law objectives (eg: ß = f(rudder pedal), engine out …)



• The FAC transmits the ELAC rudder deflection orders to the Y/D actuator and achieves the Rudder Travel Limit function.



Operational Consequences

• On most commercial A/C, the rudder

MUST NOT BE USED:

– to induce Roll,

– to counter Roll induced by any type of turbulence,

– for turn coordination (exceptionally in Direct Law, with a double hydraulic failure where YD is lost).




• On most commercial A/C, the rudder

IS ACTUALLY USED ONLY:

– during T/O and LANDING Roll,

– in case of Engine Out, as a yaw corrective action,

– during the last phase of a flare with crosswind for decrab purpose.

  

• On most commercial A/C:

– there is no need to act on the rudder abruptly,

– in case of failure leading to a loss of TLU, the rudder is to be used with   care, as per ECAM,

– there is no roll control restriction with an engine failed.


Aircraft Airbus 320-216 Flight Controls Laws

AIRBUS FLIGHT CONTROL LAWS
High AOA Protection
Load Factor Limitation
Pitch Attitude Protection
NORMAL LAW
High Speed Protection
Flight Augmentation (Yaw)
Bank Angle Protection



Low Speed Stability
Load Factor Limitation

ALTERNATE LAW
High Speed Stability
Yaw Damping Only





Load Factor Limitation

ABNORMAL ALTERNATE LAW w/o Speed Stability

Yaw Damping Only







DIRECT LAW










FLIGHT CONTROL LAWS SUMMARY
NORMAL LAW
Normal operating configuration of the system. Failure of any single computer does not affect normal law.
Covers 3-axis control, flight envelope protection, and load alleviation. Has 3 modes according to phase of flight.
Ground
Mode
  • Active when aircraft is on the ground.
  • Direct proportional relationship between the sidestick deflection and deflection of the flight controls.
  • Is active until shortly after liftoff.
  • After touchdown, ground mode is reactivated and resets the stabilizer trim to zero.
Flight
Mode
  • Becomes active shortly after takeoff and remains active until shortly before touchdown.
  • Sidestick deflection and load factor imposed on the aircraft are directly proportional, regardless of airspeed.
  • With sidestick neutral and wings level, system maintains a 1 g load in pitch.
  • No requirement to change pitch trim for changes in airspeed, configuration, or bank up to 33 degrees.
  • At full aft/fwd sidestick deflection system maintains maximum load factor for flap position.
  • Sidestick roll input commands a roll rate request.
  • Roll rate is independent of airspeed.
  • A given sidestick deflection always results in the same roll rate response.
  • Turn coordination and yaw damping are computed by the ELACs and transmitted to the FACs.
  • No rudder pedal feedback for the yaw damping and turn coordination functions.
Flare
Mode
  • Transition to flare mode occurs at 50' RA during landing.
  • System memorizes pitch attitude at 50' and begins to progressively reduce pitch, forcing pilot to flare the aircraft
  • In the event of a go-around, transition to flight mode occurs again at 50' RA.
Protections
Load factor Limitation
  • Prevents pilot from overstressing the aircraft even if full sidestick deflections are applied.
Attitude Protection
  • Pitch limited to 30 deg up, 15 deg down, and 67 deg of bank.
  • These limits are indicated by green = signs on the PFD.
  • Bank angles in excess of 33 deg require constant sidestick input.
  • If input is released the aircraft returns to and maintains 33 deg of bank.
High Angle of Attack Protection (alpha):
  • When alpha exceeds alpha prot, elevator control switches to alpha protection mode in which angle of attack is proportional to sidestick deflection.
  • Alpha max will not be exceeded even if the pilot applies full aft deflection
High Speed Protection:
  • Prevents exceeding VMO or MMO by introducing a pitch up load factor demand.
  • The pilot can NOT override the pitch up command.
Low Energy Warning:
  • Available in CONF 2,3, or FULL between 100' and 2,000' RA when TOGA not selected.
  • Produces aural "SPEED SPEED SPEED" when change in flight path alone is insufficient to regain a positive flight path (Thrust must be increased).



UTC (Universal Time Coordinate) is the primary time standard by which the world regulates clocks and time. It is, within about 1 second, mean solar time at 0° longitude; it does not observe daylight saving time. It is one of several closely related successors to Greenwich Mean Time (GMT). Local time of the point of departure and the accident site was UTC + 7.  



The sequence of events retrieved from both of Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) were as follows:


2231 UTC, the aircraft started to taxi.


2235 UTC, the aircraft took off.


2249 UTC, the flight reached cruising altitude of 32000 feet (Flight Level 320).


At 2257 UTC, the PF asked for anti-ice ON and the flight attendant announced to the passengers to return to their seat and fasten the seat belt due to weather condition and possibility of turbulence.

At 2300 UTC, the Electronic Centralized Aircraft Monitoring (ECAM) amber advisory AUTO FLT RUD TRV LIM 1 appeared. The PF asked “ECAM action”.

At 2301 UTC, FDR recorded failure on both Rudder Travel Limiter Units and triggered a chime and master caution light. The ECAM message showed “AUTO FLT RUD TRV LIM SYS” (Auto Flight Rudder Travel Limiter System). The PIC read and performed the ECAM action of AUTO FLT RUD TRV LIM SYS to set Flight Augmentation Computer (FAC) 1 and 2 push-buttons on the overhead panel to OFF then to ON one by one. Both Rudder Travel Limiter Units returned to function normally.

At 2304 UTC, the PM requested to the Ujung Pandang Upper West2 controller to deviate 15 miles left of track for weather avoidance and was approved by the controller. The aircraft then flew on a heading of 310°.

At 2306UTC, the SIC conducted cruise crew briefing including in the case of one engine inoperative or emergency descent and that Semarang Airport would be the alternate airport.

At 2309 UTC, the FDR recorded the second failure on both Rudder Travel Limiter Units and triggered a chime and master caution light. The pilots repeated the ECAM action and both Rudder Travel Limiter Units returned to function normally.

At 2311 UTC, the pilot contacted the Jakarta Upper Control3 controller and informed that the flight turned to the left off the M635 to avoid weather. The information was acknowledged and identified on the radar screen by the Jakarta Radar controller. The Jakarta Radar controller instructed the pilot to report when clear of the weather.

At 2312 UTC, the pilot requested for a higher level to FL 380 when possible and the Jakarta Radar controller asked the pilot to standby.

At 2313:41 UTC, the single chime sounded and the amber ECAM message “AUTO FLT RUD TRV LIM SYS” was displayed. This was the third failure on both Rudder Travel Limiter Units on this flight. The pilots performed the ECAM actions and the system returned to function normally.

At 2315:36 UTC, the fourth failure on both Rudder Travel Limiter Units and triggered ECAM message “AUTO FLT RUD TRV LIM SYS”, chime and master caution light.

At 2316 UTC, the Jakarta Radar controller issued a clearance to the pilot to climb to FL 340 but was not replied by the pilot. The Jakarta Radar controller then called the pilot for several times but was not replied.

At 2316:27 UTC, the fifth Master Caution which was triggered by FAC 1 FAULT followed by FDR signature of alteration 4of parameters of components controlled by FAC 1 such as RTLU 1, Windshear Detection 1 and Rudder Travel Limiter Actuator 1.

At 2316:44 UTC, the sixth Master Caution triggered by AUTO FLT FAC 1 + 2 FAULT and followed by FDR signature of alteration of parameters of components controlled by FAC 2 such as RTLU 2, Windshear Detection 2 and Rudder Travel Limiter Actuator 2. The Auto Pilot (A/P) and the Auto-thrust (A/THR) disengaged. Flight control law reverted from Normal Law to Alternate Law. The aircraft started to roll to the left up to 54° angle of bank.

Nine seconds after the autopilot disengaged, the right side-stick activated. The aircraft roll angle reduced to 9° left and then rolled back to 53° left. The input on the right side-stick was mostly pitch up and the aircraft climbed up to approximately 38,000 feet with a climb rate of up to 11,000 feet per minute.

At 2317:18 UTC, the stall warning activated and at 2317:22 UTC stopped for 1 second then continued until the end of recording.

The first left side stick input was at 2317:03 UTC for 2 seconds and at 2317:15 UTC another input for 2 seconds, then since 2317:29 UTC the input continued until the end of the recording.

The right side stick input was mostly at maximum pitch up until the end of recording.

The lowest ISIS speed recorded was 55 knots. The ISIS speed recorded fluctuated at an average of 140 knots until the end of the recording.

At 2317:41 UTC the aircraft reached the highest ISIS altitude of 38,500 feet and the largest roll angle of 104° to the left. The aircraft then lost altitude with a descent rate of up to 20,000 feet per minute.



At approximately 29,000 feet the aircraft attitude was wings level with pitch and roll angles of approximately zero with the airspeed varied between 100 and 160 knots. The Angle of Attack (AOA)5 was almost constant at approximately 40° up and the stall warning continued until the end of recording. The aircraft then lost altitude with an average rate of 12,000 feet per minute until the end of the recording.

At 2318 UTC, the aircraft disappeared from the Jakarta Radar controller screen. The aircraft last position according to the Automatic Dependent Surveillance- Broadcasting (ADS-B) radar was on coordinate 3°36‟48.36”S - 109°41‟50.47”E and the aircraft altitude was approximately 24,000 feet.

The last data recorded by FDR was at 2320:35 UTC with ISIS airspeed of 132 kts, pitch 20° up, AOA 50° up, roll 8° to left, the rate of descent 8400 ft/minute and the radio altitude was 118 feet. No emergency message was transmitted by the crew.

Characteristic of pitch and lateral

Pitch Control

When the PF performs sidestick inputs, a constant G-load maneuver is ordered, and the aircraft responds with a G-Load/Pitch rate. Therefore, the PF‟s order is consistent with the response that is "naturally" expected from the aircraft: Pitch rate at low speed; Flight Path Rate or G, at high speed.

So, if there is no input on the stick:

• The aircraft maintains the flight path, even in case of speed changes

• In case of configuration changes or thrust variations, the aircraft compensates for the pitching moment effects

• In turbulence, small deviations occur on the flight path. However, the aircraft tends to regain a steady condition.

Airbus Pitch Characteristic



Sidestick Pitch (P) input Positive (+) value means nose down input
Sidestick Roll (R) input Positive (+) value means aircraft rolls to the left
Rudder Position Positive (+) means left rudder input (left yaw)
Elevator Position Positive (+) means TE down (nose-down)
Trimmable Stabilizer (THS) Position Range: -13.5° to +4° Positive: trailing edge (TE) up (nose-down)
Aileron Position Positive (+) means trailing edge (TE) down (nose up).


Operational Recommendation:

From the moment the aircraft is stable and auto-trimmed, the PF needs to perform minor corrections on the sidestick, if the aircraft deviates from its intended flight path. The PF should not force the sidestick, or over control it. If the PF suspects an over control, they should release the sidestick.

Lateral Control

When the PF performs a lateral input on the sidestick, a roll rate is ordered and naturally obtained.

Therefore, at a bank angle of less than 33°, with no input on the sidestick, a zero roll rate is ordered, and the current bank angle is maintained. Consequently, the aircraft is laterally stable, and no aileron trim is required.

However, lateral law is also a mixture of roll and yaw demand with:

Automatic turn coordination

Automatic yaw damping

Initial yaw damper response to a major aircraft asymmetry.

In addition, if the bank angle is less than 33°, pitch compensation is provided. If the bank angle is greater than 33°, spiral stability is reintroduced and pitch compensation is no longer available. This is because, in normal situations, there is no operational reason to fly with such high bank angles for a long period of time.


Airbus Lateral Characteristic



Operational Recommendation:

During a normal turn (bank angle less than 33°), in level flight:

• The PF moves the sidestick laterally (the more the sidestick is moved laterally, the greater the resulting roll rate - e.g. 15°/s at max deflection)

• It is not necessary to make a pitch correction

• It is not necessary to use the rudder.

In the case of steep turns (bank angle greater than 33°), the PF must apply:

• Lateral pressure on the sidestick to maintain bank

• Aft pressure on the sidestick to maintain level flight.

Rudder Travel Limitation

This function limits rudder deflection based on speed in order to avoid high structural loads. It is governed by the following law:



If both FACs lose the rudder travel limitation function, the value of the rudder deflection limit is locked at the time of the second failure.

When the slats are extended, the FACs automatically set the rudder deflection limit at the low-speed setting (maximum authorized deflection).


The CVR contained 2 hours and 4 minutes of good quality recording data. The significant excerpts from the CVR are as follow:





Airplane Upset: An airplane in flight unintentionally exceeding the parameters normally experienced in line operations or training:

• Pitch attitude greater than 25 degree, nose up.

• Pitch attitude greater than 10 degree, nose down.

• Bank angle greater than 45 degree.

• Within the above parameters, but flying at airspeeds inappropriate for the conditions.  




The summary of the examination found the electronic cards shows the evidence of cracking of soldering of both channel A and channel B. Those cracks could generate loss of electrical continuity and lead to a TLU failure.

Thermal cycles associated to powered/not-powered conditions and ground/flight conditions, generate fatigue phenomenon of the soldering, and may result in soldering cracking. Soldering cracking could induce a disconnection of components from the circuit. The disconnections could create a loss of the affected RTLU channel.

The electronic module pictures are shown above.