Secret Squirrel Considers Alarming Aircraft Problems.

Secret Squirrel has noticed the Airbus A380 has almost repeated what it did in Brazil, this time out of Venezuela when it encountered extreme turbulence as did the Brazilian crash A380.........and...the same thing happened.........almost.But Secret Squirrel has discovered a link between the two, and also a link involving yet many other airliner problems with speed,autopilots, and automated flight controls and instrumentation.Strangely,as things will be expounded on, they're actually not uncommon, but alarmingly common. But firstly let's have a look at the Brazilian crash.Some experts have blamed the speed monitors – called Pitot tubes – for fatally misleading the crew of Flight 447 that crashed in the ocean off the coast of Brazil on May 31, killing all 228 people on board.

http://www.dailymail.co.uk/news/article-1191929/Air-France-rushes-refit-speed-sensors-caused-crash-Flight-447.html

"Air France pledged to immediately re-fit the entire fleet of 35 long-haul Air France Airbus jets came after unions urged pilots not to fly them until the key sensors were updated. Investigators believe the sensors may have iced over during a fierce thunderstorm and delivered dangerously false information to the plane’s computers which caused the pilot to slow down so much the plane stalled and pitched into a
deadly tailspin.There was pondering that the the tail section of the plane, which includes the rudder and the vertical stabilizer - which keeps the nose from swinging back and forth – was sheared off by turbulence.The Airbus 330 has a ‘rudder-limiter' which constricts how much the rudder can move at high speeds. If it were to move too far while travelling fast, it could break off and take the tail section with it, said flight safety analysts.Asked if the rudder or stabilizer being sheared off could have brought the jet down, he said: ‘Absolutely. You need a rudder. And you need the rudder limiter on there to make sure the rudder doesn't get torn off or cause havoc with the plane's aerodynamics.’ ‘If you had a wrong speed being fed to the computer by the Pitot tube, it might allow the rudder to over travel,’ said Peter Goelz, a former managing director of the National Transportation Safety Board in Brazil.
The speed sensors need to be ultra-sensitive because the safety margin for a plane's speed at high altitude is so narrow that pilots call it 'coffin corner'. Either 70mph too fast or too slow and a jet can either stall or nosedive.One Air France pilot wrote on an Internet forum for airline professionals:
‘If the pitot tube is unreliable in bad weather and at high altitude, the plane becomes an airborne death trap. We need to know exactly how fast we are going or the plane will simply fall out of the sky.
'Another Airbus captain wrote: 'I have never been taught unusual altitude recovery in the simulator because I was told the plane has so many
in built protections. This sounds like very similar reasoning to what happened with the Titanic.'

Erick Derivry, spokesman of the main SNPL pilots union, said a threat to ask all pilots to stop flying the Airbus A330 and A340 jets elicited a 'very swift and positive' response from Air France.He said: 'Air France has provided us with an extremely pro-active and very accelerated replacement programme. From today, all Air France A330 and A340 flights will use planes equipped with at least two new sensors out of three on board.'"

Here from...
http://www.technologyreview.com/blog/editors/26821/

"What causes a passenger jet to suddenly plunge intact--with engines and wing surfaces working just fine--from cruising altitude into the middle of the Atlantic Ocean, killing everyone aboard?The full report on Air France Flight 447 in 2009, in which 228 people died, is still in the works. But one expert told me that preliminary
data suggest a role for human confusion, and a failure to focus on the plane's "attitude" or position in the sky: nose up or down, wings tilting left or right.
"You have a perfectly good airplane, other than not having airspeed data," R. John Hansman, aeronautics professor at MIT, mentioned to me today after we discussed the release of preliminary data on the accident, recovered from "black boxes" fetched from 12,000 feet below the surface of the ocean. "They clearly lost situational awareness. If they'd had it, they would have been able to regain control of the airplane."French investigators have said that the plane was entering an area of turbulence, possibly severe. They've also said the plane suffered a failure of its airspeed indicators, possibly because of icing on a sensors known as a pitot tubes.The aircraft climbed from 37,500 feet to 38,000 feet, and "stall warning" was triggered.This meant they were in danger of losing "lift." Why those warnings were sounding---whether they were valid, or based on inaccurate speed data--or whether the pilots ignored the stall warning because they saw high speeds that were inaccurate, is unclear.
It was late at night, more than four hours into the flight. Stall warnings were sounding. Speed indicators were going haywire. The captain had been called to the cockpit by an alarmed co-pilot. It took only about three minutes for the plane to plunge 38,000 feet to crash, belly first, on the surface of the ocean."
Air France Flight 447 slammed into the Atlantic Ocean, intact and belly first, at such a high speed that the 228 people aboard probably had no time to even inflate their life jackets, French investigators said Thursday in their first report into the June 1 accident."
More comes from......
http://www.nypost.com/p/news/international/item_MNTYiMvhUX0vyhMe8ZTb7N#ixzz1XJUslNuh

"The aircraft sent out automated messages starting At 11:10 p.m., a cascade of horrific problems began.Automatic messages relayed by the jetliner indicate the autopilot had disengaged, suggesting Dubois and his two co-pilots were trying to
thread their way through the dangerous clouds manually.A key computer system had switched to alternative power and controls needed to keep the plane stable had been damaged.An alarm sounded, indicating the deterioration of flight systems.
At 11:13 p.m., more automatic messages reported the failure of systems to monitor air speed, altitude and direction. Control of the main flight computer and wing spoilers also failed.The last automatic message, at 11:14 p.m., indicated complete electrical failure and a massive loss of cabin pressure -- catastrophic events, indicating that the plane was breaking apart and plunging toward the ocean."
Now,what happened to another Air France A380 when it encountered extreme turbalance on a flight from Venezuela to Paris?'When it encountered extreme turbulence, the Air France jet almost stalled and went into a nose-dive after hitting a storm.In the latest drama, the autopilot shut down as the plane hit a storm at 35,000 feet while flying from Venezuelan capital Caracas to Paris.The high-altitude alert in July chillingly echoed the cockpit chaos that preceded the fatal crash of an Air France Rio-Paris flight two years earlier, in which all 228 passengers died.

French daily Le Figaro said it had seen a report into the alert and Air France had launched a full investigation into the cause of the malfunction.The paper said the drama was 'comparable in every way' with the crash of doomed flight AF447 on June 1, 2009.It added: 'Only this time there were no victims, only two of the crew who were slightly hurt.'According to the report, the A340 Airbus was at its cruising altitude of 35,000ft, just as flight AF447 was before the accident, when it
hit extreme turbulence.'The plane hit a strong variation in wind speed and found itself going too fast - a situation which set off the "overspeed alarm".(With the ill fated A380 the incorrect airspeed data was the apparent cause of the disengagement of the autopilot, the reason the pilots lost control of the aircraft remains a mystery, in particular because pilots would normally try to lower the nose in case of a stall.)'At this point, the autopilot disconnected. It went into a steep climb and began losing speed.'The plane then slowed drastically to just 205
knots, with an Air France pilot telling Le Figaro: 'This was just three knots away from stalling and from probable catastrophe.'"

Now we're getting somewhere.What happened...."false" speed readings? The autopilot disconnects,perhaps, yes it did, it is indicated it did, the pilots had to fly the aircraft, but not the speed loss, the attitude of the aircraft.Clearly there is a problem, turbulance encountered, auto pilot disconnects but aircraft doesn't fly straight and level, and at speed, instead it goes in to a steep climb, begins to loose speed,the engines don't power up to compensate....clearly then there is a major problem, it centers about the autopilot AND flight computer problems (Airbus A380 is HEAVILY automated, and it makes it difficult for the pilots to fly manually, there is a joystick on either side for them to use when flying manually, a joystick.Here we can see the actula flight deck itself......

http://www.futurastudios.com/airbus-380-flight-deck/airbus-380-flight-deck-front.jpg

The Flight 447 accident may have some relevant similarities to other A330 incidents with other carriers. Three similar reports are on file at the Australian Transport Safety Bureau (ATSB), with two incidents relating to Airbus A330s with flight computer problems, plus one which involved a Boeing 777. In the October 2008 accident, this fault caused injuries to passengers and damage to the aircraft on Qantas Flight 72, en route from Singapore to Perth, Western Australia, which was forced into a dive by a malfunctioning ADIRU. These incidents often started with the automatic pilot's disengaging and sending out ADIRU failure messages. Incorrect speed indications were also observed.The airframe and ADIRU involved in the Qantas Flight 72 accident were also previously involved in another incident on Qantas Flight 68, 2006. The Qantas aircraft were equipped with ADIRUs manufactured by Northrop Grumman, while Flight 447 was equipped with an ADIRU manufactured by Honeywell. A memo leaked from Airbus suggests that there was no evidence that the Flight 447 ADIRU malfunction was similar to the failure in
the Qantas incidents.

An Air Data Inertial Reference Unit (ADIRU) is a key component of the integrated Air Data Inertial Reference System (ADIRS), that supplies air data (airspeed, angle of attack and altitude) and inertial reference (position and attitude) information to the pilots' Electronic Flight Instrument System displays as well as other systems on the aircraft such as the engines, autopilot, flight control and landing gear
systems. An ADIRU acts as a single, fault tolerant source of navigational data for both pilots of an aircraft.The ADR component of an ADIRU provides airspeed, Mach, angle of attack, temperature and barometric altitude data. Ram air pressure and static pressures used in calculating airspeed are measured by small Air data modules (ADM) located as close as possible to the respective pitot and static pressure sensors. The ADMs transmit their pressures to the ADIRUs through ARINC 429 data buses.The IR component of an ADIRU gives attitude, flight path vector, ground speed and positional data.The ring laser gyroscope is a core enabling technology in the system, and is used together with accelerometers, GPS and other sensors to provide raw data. The primary benefits of a ring laser over older mechanical gyroscopes are that there are no moving parts, it is rugged and lightweight, frictionless and does not resist a change in precession.

Analysis of complex systems is itself so difficult as to be subject to errors in the certification process. Complex interactions between flight computers and ADIRU's can lead to counter-intuitive behaviour for the crew in the event of a failure. In the case of Qantas Flight 72, the captain switched the source of IR data from ADIRU1 to ADIRU3 following a failure of ADIRU1; however ADIRU1 continued to supply ADR data to the captain's primary flight display. In addition, the master flight control computer (PRIM1) was switched from PRIM1 to PRIM2, then PRIM2 back to PRIM1, thereby creating a situation of uncertainty for the crew who did not know which redundant systems they were relying upon.

Take note of this......

http://www.routesonline.com/news/24/atw/6975/qantas-suffers-second-a330-adiru-failure/

Qantas suffers second A330 ADIRU failure
by Geoffrey Thomas

The Australian Transport Safety Bureau said it was advised on Dec. 27 of an occurrence that day involving a QF A330-300 cruising at 36,000 ft. on its way from Perth to Singapore. Some 260 nm. northwest of Perth the autopilot disconnected and the crew received an Electronic Centralized Aircraft Monitor message (NAV IR 1 fault) indicating a problem with ADIRU No. 1.The crew implemented the new Airbus Operations Engineering Bulletin procedure by selecting the IR 1 and ADR 1 pushbuttons to off (ATWOnline, Oct. 15, 2008). The aircraft returned to Perth.
ATSB said the incident "appears to be a similar event to a previous event involving an A330 aircraft." In the October incident, 70 of the 313 people onboard the A330 flying from SIN to PER were injured when the aircraft pitched up and then dove twice after a failure of ADIRU 1. An ATSB preliminary report issued in November suggested the possibility that transmissions from a naval communications station interfered with onboard systems.

Now note this also, involving ADIRU and autopilot, and note what happened.........

http://www.airlinesafety.com/faq/777DataFailure.htm

On August 1, 2005, a Boeing 777-200, which had departed from Perth, received an EICAS (Engine Indication and Crew Alerting System) warning of  low airspeed, as the plane was climbing through FL (flight level) 380.  Simultaneously, the aircraft's slip/skid indication moved full right, on the PFD (Primary Flight Display). The PFD speed tape also displayed contradictory information: that the plane was approaching both the high speed limit and the low speed (stall) limit. The aircraft, still connected to the autopilot, pitched up and climbed to approximately FL410 as the airspeed decreased from 270 kts to 158 kts. The stall warning devices also activated.The PIC (pilot in command) "disconnected the autopilot and lowered the nose of the aircraft. The autothrottle commanded an increase in thrust which the PIC countered by manually moving the thrust levers to the idle position. The aircraft pitched up again and climbed 2,000 ft." The PIC advised ATC "that they could not maintain altitude and requested a descent and radar assistance. The crew was able to verify with ATC the aircraft speed and altitude."The PFD indications became accurate again as they were descending through FL200. The PIC attempted to use both the left and right autopilots, but had to turn them off after each one produced undesired command responses.  "There were no control difficulties experienced when the aircraft was flown manually, but the autothrottle 'arm' switches remained in the 'armed' position."ATC radar vectors put the plane in position to conduct an ILS to R 03 at Perth. When they reached 3,000 ft, the PFD again began indicating erroneous low airspeed information. The autothrottle again responded by advancing the thrust levers. Since the pilot can override that
command, simply by manually adjusting those thrust levers, the plane was able to land safely at Perth.  The FDR (flight data recorder), the CVR (cockpit voice recorder) and the ADIRU (air data inertial reference unit) were removed from the
plane, for a detailed examination. Under the supervision of the American NTSB, the ADIRU was shipped to its manufacturer for detailed analysis.The FDR data confirmed the erroneous acceleration values had been displayed on the PFDs, as the pilots reported.   The ADIRU produced those erroneous acceleration values and they were used by the PFC (primary flight computer). As it was designed to do, the PFC compared the information from the ADIRU, to the information coming from the SAARU (Standby Air Data and Attitude Reference Unit). That comparison ability
enabled the PFC to reduce the severity of the initial pitching motion of the aircraft.

Have a look at this,or rather ALL OF THESE..........

http://en.wikipedia.org/wiki/Air_Data_Inertial_Reference_Unit#Malaysia_Airlines_Flight_124

Alitalia A-320

On 25 June 2005, an Alitalia Airbus A320-200 registered as I-BIKE departed Milan with a defective ADIRU as permitted by the Minimum Equipment List. While approaching London Heathrow Airport during deteriorating weather another ADIRU failed, leaving only one operable. In the subsequent confusion the third was inadvertently reset, losing its reference heading and disabling several automatic functions. The crew was able to effect a safe landing after declaring a Pan-pan.

Malaysia Airlines Flight 124

On 1 August 2005 a serious incident involving Malaysia Airlines Flight 124, occurred when a Boeing 777-2H6ER (9M-MRG) flying from Perth to Kuala Lumpur also involved an ADIRU fault resulting in uncommanded manoeuvres by the aircraft acting on false indications. In that incident the incorrect data impacted all planes of movement while the aircraft was climbing through 38,000 feet (11,600 m). The aircraft pitched up and climbed to around 41,000 feet (12,500 m), with the stall warning activated. The pilots recovered the aircraft with the autopilot disengaged and requested a return to Perth. During the return to Perth, both the left and right autopilots were briefly activated by the crew, but in both instances the aircraft pitched down and banked to the right. The aircraft was flown manually for the remainder of the flight and landed safely in Perth.

Qantas Flight 68

On 12 September 2006, Qantas Flight 68, Airbus A330 registration VH-QPA, from Hong Kong to Perth exhibited ADIRU problems but without causing any disruption to the flight. At 41,000 feet (12,000 m) and estimated position 530 nautical miles (980 km) north of Learmonth, Western Australia, NAV IR1 FAULT then, 30 minutes later, NAV ADR 1 FAULT notifications were received on the ECAM identifying navigation system faults in Inertial Reference Unit 1, then in ADR 1 respectively. The crew reported to the later Qantas Flight 72 investigation involving the same airframe and ADIRU that they had received numerous warning and caution messages which changed too quickly to be dealt with. While investigating the problem, the crew noticed a weak and intermittent ADR 1 FAULT light and elected to switch off ADR 1, after which they experienced no further problems. There was no impact on the flight controls throughout the event. The ADIRU manufacturer's
recommended maintenance procedures were carried out after the flight and system testing found no further fault.

 Jetstar Flight 7

On 7 February 2008, a similar aircraft (VH-EBC) operated by Qantas subsidiary Jetstar Airways was involved in a similar occurrence while conducting the JQ7 service from Sydney to Ho Chi Minh City, Vietnam. In this event - which occurred 1,760 nautical miles (3,260 km) east of Learmonth - many of the same errors occurred in the ADIRU unit. The crew followed the relevant procedure applicable at the time and the flight continued without problems.

 Qantas Flight 72

On 7 October 2008, Qantas Flight 72, an Airbus A330, departed Singapore for Perth. Some time into the flight, while cruising at 37,000 ft, a failure in the No.1 ADIRU led to the autopilot automatically disengaging followed by two sudden uncommanded pitch down manoeuvres, according to the Australian Transport Safety Bureau (ATSB). The accident injured up to 74 passengers and crew, ranging from minor to serious injuries. The aircraft was able to make an emergency landing without further injuries. The aircraft was equipped with a Northrop Grumman made ADIRS, which investigators sent to the manufacturer for further testing.

 Qantas Flight 71

On 27 December 2008, Qantas Flight 71 from Perth to Singapore, the same A330-300 registration VH-QPA and the same ADIRU as involved in the Qantas Flight 68 incident, was involved in an incident at 36,000 feet approximately 260 nautical miles (480 km) north-west of Perth and 350 nautical miles (650 km) south of Learmonth Airport at 1729 WST. The autopilot disconnected and the crew received an alert indicating a problem with ADIRU Number 1.

 Air France Flight 447

On 1 June 2009, Air France Flight 447, an Airbus A330 en route from Rio de Janeiro to Paris, disappeared over the Atlantic Ocean after transmitting automated messages indicating faults with various equipment, including the ADIRU. While examining possibly related events of weather-related loss of ADIRS, the NTSB decided to investigate two similar cases on cruising A330s.
TAM Flight 8091
On a 21 May 2009 Miami-Sao Paulo TAM Flight 8091 registered as PT-MVB, and on a 23 June 2009 Hong Kong-Tokyo Northwest Airlines Flight 8 registered as N805NW each saw sudden loss of airspeed data at cruise altitude and consequent loss of ADIRS control.

Now isn't it wonderful with the degree of automation we have,with the technical skill of the systems designers,the computer programmers,remember!Remember when you board your ADIRU/Autopilot equipped aircraft,and you hear your welcoming announcement, "Welcome aboard your flight where nothing can go wrong,can go wrong,can go wrong,can go wrong........"