MAS 777 Emergency
Evertonian
MH124 with 177 passengers was 25 minutes into a flight
The plane was cruising at a speed of about 850 kmph, over the tip of the northern Australian coastline, when the incident occurred
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Several of the 177 passengers on board panicked after one steward dropped a tray of drinks and another began praying.
AAAAAhhhhhhhh the Satay Express. I believe that the reason for the 'jet upset' was that the worlds best satay's had been incorrectly loaded and the sudden change of C of G by the aforementioned steward relocating the cart of peanut sauce was the real reason behind the days drama.
World's best cabin service award looking a bit shakey this year MAS.
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Captain nervous wreck
I can say for certain the captain was not at all calm and collected, the first officer was definately in more control of himself. The aircraft suffered an ADIRU failure which caused the minimum manouvre and overspeed margins on the speed tape to converge (like a coffin corner indication - only at FL380) the indicated airspeed was rock steady but when the minimum speed indication rose up the speed tape it caused the auto throttle to think the aircraft was flying to slow and constantly tried to increase power. There was nothing wrong with the engines at all! The aircraft was basically grounded due to no ADIRU spare, but the ATSB got involved and took the FDR and CVR - so the aircraft wasnt going anywhere anyway.
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Oh, is that what it was.
I thought the 'coffin corner' widened with decreased height / increased air density, therefore meaning that all that was needed was a descent...(?)
Surely there must be more to it than that.....
520.
Surely there must be more to it than that.....
520.
520,
The problem was with the indications, not the speeds. The ADIRU fault caused the wrong high and low speed limits to be displayed on the PFD. The actual limits remain the same. But because of the fault, in this case, it appeared that MMO and VLS were coming together on the PFD speed indication, when in actual fact they were not.
It was one of those cases where you can not always believe what you see.
Don.
The problem was with the indications, not the speeds. The ADIRU fault caused the wrong high and low speed limits to be displayed on the PFD. The actual limits remain the same. But because of the fault, in this case, it appeared that MMO and VLS were coming together on the PFD speed indication, when in actual fact they were not.
It was one of those cases where you can not always believe what you see.
Don.
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The following was released by Boeing not so long ago. It seems to relate to the incident being discussed in this thread.
Hope that clarifies things for some people.
SUMMARY:
A 777-200ER operator experienced a significant nose-up pitch event while climbing through FL360 accompanied by indication, warning, autopilot, autothrottle, and flight control anomalies. The flight crew disconnected the autopilot and stabilized the airplane, during which time the airplane climbed above 41000 feet, decelerated to a minimum airspeed of 158 knots and activated the stick shaker. The flight returned to the origin airport. There were no injuries reported. The event is under investigation by the Australian Transportation Safety Bureau (ATSB). This message is being sent to advise 777 operators of the reported condition and to provide recommended operator actions.
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DESCRIPTION:
A review of the Flight Data Recorder (FDR) data for this event shows that abrupt and persistent offsets in the acceleration outputs of the Air Data Inertial Reference Unit (ADIRU) are the suspected cause of the event and reported system anomalies. The design of the fault-tolerant ADIRU is intended to suppress such erroneous outputs. Erroneous accelerations will affect the Primary Flight Computer (PFC) control laws during manual and automatic flight. The PFC's compare the outputs of the ADIRU with the outputs of the Standby Air Data and Attitude Reference Unit (SAARU). During the event, this comparison of ADIRU and SAARU data by the PFC reduced the severity of the pitch-up resulting from the erroneous ADIRU data. The comparison function requires that an operating SAARU be present.
Therefore, until the ADIRU anomaly is better understood, Boeing recommends that operators no longer dispatch with an inoperative SAARU as is currently permitted by the master minimum equipment list (MMEL). OPERATOR ACTION:
Boeing recommends that operators not utilize the SAARU dispatch relief provided in MMEL item 34-21-7 until such time as root cause and corrective action are identified and implemented. Boeing is coordinating with the FAA and changes to the MMEL are being considered relative to SAARU dispatch relief. Boeing will advise the 777 fleet of any significant developments based on the investigation results.
In the event that the conditions reported should occur, flight crews are advised to follow procedures in the Flight Crew Training Manual. Specifically, flight crews should take the following actions if the autoflight systems produce undesired results:
The flight crew should disconnect the autopilot and manually fly the airplane. Although initial manual control forces may be high, the affects of the ADIRU anomaly on manual control forces are expected to diminish within 10 seconds and should be back to near nominal within 2 minutes.
The flight crew should also disconnect and disarm the autothrottle via the arm switches on the MCP if there is any undesired behavior.
The flight crew should cross check the standby instruments if there is any doubt as to the accuracy of the primary airspeed, altitude and attitude.
The event airplane was dispatched with maintenance message (MM) 34-20010 present (ADIRU Internal Fault) and the "ADIRU" Status message was subsequently displayed during flight.
ADIRU's with MM 34-20010 have sufficient resources to meet the reliability requirements of the ADIRU. There are no MMEL restrictions on dispatch with MM 34-20010 present. If a second like fault occurs within the ADIRU, the ADIRU Status message is displayed and the ADIRU continues to output its voted solutions for Air Data and Inertial parameters. There is 777 MMEL dispatch relief to operate with an ADIRU Status message for 3 days.
At this time, no relationship has been established between the presence of the "ADIRU" Status message and the erroneous ADIRU data event. If a relationship is established, operators will be notified. There is no change to Boeing's recommendation that dispatch with an "ADIRU" Status message present is acceptable in accordance with the MMEL.
Boeing and Honeywell (ADIRU supplier) are supporting the ATSB investigation and are addressing the issues raised by this event with the highest priority. If the investigation shows that additional actions are necessary, operators will be notified.
The Boeing Company
A 777-200ER operator experienced a significant nose-up pitch event while climbing through FL360 accompanied by indication, warning, autopilot, autothrottle, and flight control anomalies. The flight crew disconnected the autopilot and stabilized the airplane, during which time the airplane climbed above 41000 feet, decelerated to a minimum airspeed of 158 knots and activated the stick shaker. The flight returned to the origin airport. There were no injuries reported. The event is under investigation by the Australian Transportation Safety Bureau (ATSB). This message is being sent to advise 777 operators of the reported condition and to provide recommended operator actions.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
DESCRIPTION:
A review of the Flight Data Recorder (FDR) data for this event shows that abrupt and persistent offsets in the acceleration outputs of the Air Data Inertial Reference Unit (ADIRU) are the suspected cause of the event and reported system anomalies. The design of the fault-tolerant ADIRU is intended to suppress such erroneous outputs. Erroneous accelerations will affect the Primary Flight Computer (PFC) control laws during manual and automatic flight. The PFC's compare the outputs of the ADIRU with the outputs of the Standby Air Data and Attitude Reference Unit (SAARU). During the event, this comparison of ADIRU and SAARU data by the PFC reduced the severity of the pitch-up resulting from the erroneous ADIRU data. The comparison function requires that an operating SAARU be present.
Therefore, until the ADIRU anomaly is better understood, Boeing recommends that operators no longer dispatch with an inoperative SAARU as is currently permitted by the master minimum equipment list (MMEL). OPERATOR ACTION:
Boeing recommends that operators not utilize the SAARU dispatch relief provided in MMEL item 34-21-7 until such time as root cause and corrective action are identified and implemented. Boeing is coordinating with the FAA and changes to the MMEL are being considered relative to SAARU dispatch relief. Boeing will advise the 777 fleet of any significant developments based on the investigation results.
In the event that the conditions reported should occur, flight crews are advised to follow procedures in the Flight Crew Training Manual. Specifically, flight crews should take the following actions if the autoflight systems produce undesired results:
The flight crew should disconnect the autopilot and manually fly the airplane. Although initial manual control forces may be high, the affects of the ADIRU anomaly on manual control forces are expected to diminish within 10 seconds and should be back to near nominal within 2 minutes.
The flight crew should also disconnect and disarm the autothrottle via the arm switches on the MCP if there is any undesired behavior.
The flight crew should cross check the standby instruments if there is any doubt as to the accuracy of the primary airspeed, altitude and attitude.
The event airplane was dispatched with maintenance message (MM) 34-20010 present (ADIRU Internal Fault) and the "ADIRU" Status message was subsequently displayed during flight.
ADIRU's with MM 34-20010 have sufficient resources to meet the reliability requirements of the ADIRU. There are no MMEL restrictions on dispatch with MM 34-20010 present. If a second like fault occurs within the ADIRU, the ADIRU Status message is displayed and the ADIRU continues to output its voted solutions for Air Data and Inertial parameters. There is 777 MMEL dispatch relief to operate with an ADIRU Status message for 3 days.
At this time, no relationship has been established between the presence of the "ADIRU" Status message and the erroneous ADIRU data event. If a relationship is established, operators will be notified. There is no change to Boeing's recommendation that dispatch with an "ADIRU" Status message present is acceptable in accordance with the MMEL.
Boeing and Honeywell (ADIRU supplier) are supporting the ATSB investigation and are addressing the issues raised by this event with the highest priority. If the investigation shows that additional actions are necessary, operators will be notified.
The Boeing Company
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Armchair Critics
Thanks Gigabitz, just saw the release by Boeing too.Guess that will shut up those armchair experts who claims to know better with just a smidgen of ATPL & Big Jet Theory & immediately accuse the poor skipper of lying 
Btw, here's what the local rag published recently:
The Malay Mail
Nerves of steel in mid-air save 193 lives
EDDIE CHUA
Aug 14
--------------------------------------------------------------------------------
A RECORDED radio conversation between the two pilots of flight MH124, which plunged 200 metres shortly after take-off from Perth recently, and Perth air-traffic controllers showed remarkable calmness on the part of the pilots as they battled to recover control of their 777-200 plane.
The August 1 recording, which was made available to the Sunday Mail, showed that pilot Capt Norhisham Kassim and first officer Caleb Foong did not panic as they manually piloted the aircraft to prevent the engine from stalling.
Their action saved the lives of all the 193 passengers – some of whom were crying and praying as the plane plunged – and crew members.
Following the incident at 30,000 feet, the pilots had alerted the Perth control tower and decided to return to the airport. However, they did not declare an emergency but merely requested for priority landing.
The following are excerpts from the recording of the mid-air crisis:
Some 20 minutes into the flight, Perth control tower asked about the condition of flight MH124 to Kuala Lumpur. The plane, which took off from Perth at 4.45pm, was flying above the northern Australian coastline at the time at a cruising speed of about 850kmph.
Foong: “Operating was normal.”
But a few minutes later, Norhisham and Foong was forced to take over the yoke (control column) manually when they found that the flight-control computers, which was piloting the aircraft automatically, had failed to respond accurately, providing wrong flight readings and commanding the plane to generate extra thrust to its engines. This caused the plane to nosedive.
At the same time, the plane, plunged some 200 metres as it ploughed into turbulent winds, including a ‘wind shear’ (localised change in wind speed and, or direction over a short distance) which caused the plane to wobble violently.
Panic broke out in the cabin, with passengers hanging onto their seats, some crying and saying their prayers.
The two pilots, meanwhile, made a split-second decision and quickly steered the flight back into position and prevented it from stalling.
“It was a crucial decision by the pilots. They made the decision almost spontaneously. That probably prevented a disaster,” an aviation source told Sunday Mail.
The control tower, however, had yet to realise the drama in mid-air.
The first sign that the plane was in trouble came when Foong calmly reported to the control tower.
Foong: “(Asking permission to) hold the flight course due to technical problem...”
He had also asked to maintain the flight at 370 degrees.
The air-traffic controller took note of the call and allowed the flight to maintain its course.
Air-traffic controller: “Are you proceeding to destination or returning to Perth?”
Foong (after a few moments): “Standby, Sir, standby...”
There was no radio contact for almost two minutes before Foong returned.
Foong: “There is an instrument problem... trying to arrest the uncontrollable flight control.”
The air-traffic controller then permitted him to turn around to Perth, providing him the bearings.
Preparing the plane to land, the air-traffic controller guided the pilots, allocating them their approaching runway and informing them of the wind speed and temperature reading at the airport.
Foong, again calmly returning to the radio, asked the control tower to allow the plane to make unrestricted descend.
Foong: “Be advised, we have problem with the auto throttle... auto throttle is at uncontrollable position... request for unrestricted descend for pilot approach flight.”
Air-traffic controller: “Request approved...”
After getting this approval, Foong addressed the passengers about the situation and told them the plane was returning to Perth. The radio in the cockpit crackled.
Air-traffic controller: “MH124, do you request any assistance at approaching on normal landing?”
For the first time, Norhisham, came on the radio.
Norhisham: “Instrument problem... indication problem... also having difficulties in maintaining the flight control... request assistance on landing... requesting assistance on landing.”
The air-traffic controller responded and told him the plane was 64 miles from the airport and should approach runaway 03 for landing.
He also reconfirmed the plane’s bearings with the pilot.
As Perth airport was making the preparation for a landing, the tower radioed MH124, to confirm the number of passengers aboard and if the plane was carrying any dangerous cargo.
Unknown to MH124, the tower was already preparing for a full emergency landing and the other planes were put on hold for about four minutes.
At this point, MH124 was 10 miles away from the airport.
A last check between the control tower and the fire and emergency team was quickly made to confirm the approach.
When Foong radioed the tower for the last time before preparing to land, a woman air-traffic controller took charge and quickly ran through a final checklist, including MH124’s bearings. She then guided the plane into the airport.
Air-traffic controller: You can land now.”
Foong: “Good to land.”
The Malay Mail had reported that the Australian Transport Safety Bureau were full of praises for both the pilots for their bravery during the crisis and for averting a disaster.
==============================================
Very dramatic reporting indeed, unfortunately the reporter didn't check his facts again ......didn't know whether to laugh or cry.....
Btw, here's what the local rag published recently:
The Malay Mail
Nerves of steel in mid-air save 193 lives
EDDIE CHUA
Aug 14
--------------------------------------------------------------------------------
A RECORDED radio conversation between the two pilots of flight MH124, which plunged 200 metres shortly after take-off from Perth recently, and Perth air-traffic controllers showed remarkable calmness on the part of the pilots as they battled to recover control of their 777-200 plane.
The August 1 recording, which was made available to the Sunday Mail, showed that pilot Capt Norhisham Kassim and first officer Caleb Foong did not panic as they manually piloted the aircraft to prevent the engine from stalling.
Their action saved the lives of all the 193 passengers – some of whom were crying and praying as the plane plunged – and crew members.
Following the incident at 30,000 feet, the pilots had alerted the Perth control tower and decided to return to the airport. However, they did not declare an emergency but merely requested for priority landing.
The following are excerpts from the recording of the mid-air crisis:
Some 20 minutes into the flight, Perth control tower asked about the condition of flight MH124 to Kuala Lumpur. The plane, which took off from Perth at 4.45pm, was flying above the northern Australian coastline at the time at a cruising speed of about 850kmph.
Foong: “Operating was normal.”
But a few minutes later, Norhisham and Foong was forced to take over the yoke (control column) manually when they found that the flight-control computers, which was piloting the aircraft automatically, had failed to respond accurately, providing wrong flight readings and commanding the plane to generate extra thrust to its engines. This caused the plane to nosedive.
At the same time, the plane, plunged some 200 metres as it ploughed into turbulent winds, including a ‘wind shear’ (localised change in wind speed and, or direction over a short distance) which caused the plane to wobble violently.
Panic broke out in the cabin, with passengers hanging onto their seats, some crying and saying their prayers.
The two pilots, meanwhile, made a split-second decision and quickly steered the flight back into position and prevented it from stalling.
“It was a crucial decision by the pilots. They made the decision almost spontaneously. That probably prevented a disaster,” an aviation source told Sunday Mail.
The control tower, however, had yet to realise the drama in mid-air.
The first sign that the plane was in trouble came when Foong calmly reported to the control tower.
Foong: “(Asking permission to) hold the flight course due to technical problem...”
He had also asked to maintain the flight at 370 degrees.
The air-traffic controller took note of the call and allowed the flight to maintain its course.
Air-traffic controller: “Are you proceeding to destination or returning to Perth?”
Foong (after a few moments): “Standby, Sir, standby...”
There was no radio contact for almost two minutes before Foong returned.
Foong: “There is an instrument problem... trying to arrest the uncontrollable flight control.”
The air-traffic controller then permitted him to turn around to Perth, providing him the bearings.
Preparing the plane to land, the air-traffic controller guided the pilots, allocating them their approaching runway and informing them of the wind speed and temperature reading at the airport.
Foong, again calmly returning to the radio, asked the control tower to allow the plane to make unrestricted descend.
Foong: “Be advised, we have problem with the auto throttle... auto throttle is at uncontrollable position... request for unrestricted descend for pilot approach flight.”
Air-traffic controller: “Request approved...”
After getting this approval, Foong addressed the passengers about the situation and told them the plane was returning to Perth. The radio in the cockpit crackled.
Air-traffic controller: “MH124, do you request any assistance at approaching on normal landing?”
For the first time, Norhisham, came on the radio.
Norhisham: “Instrument problem... indication problem... also having difficulties in maintaining the flight control... request assistance on landing... requesting assistance on landing.”
The air-traffic controller responded and told him the plane was 64 miles from the airport and should approach runaway 03 for landing.
He also reconfirmed the plane’s bearings with the pilot.
As Perth airport was making the preparation for a landing, the tower radioed MH124, to confirm the number of passengers aboard and if the plane was carrying any dangerous cargo.
Unknown to MH124, the tower was already preparing for a full emergency landing and the other planes were put on hold for about four minutes.
At this point, MH124 was 10 miles away from the airport.
A last check between the control tower and the fire and emergency team was quickly made to confirm the approach.
When Foong radioed the tower for the last time before preparing to land, a woman air-traffic controller took charge and quickly ran through a final checklist, including MH124’s bearings. She then guided the plane into the airport.
Air-traffic controller: You can land now.”
Foong: “Good to land.”
The Malay Mail had reported that the Australian Transport Safety Bureau were full of praises for both the pilots for their bravery during the crisis and for averting a disaster.
==============================================
Very dramatic reporting indeed, unfortunately the reporter didn't check his facts again ......didn't know whether to laugh or cry.....
SAARU data by the PFC reduced the severity of the pitch-up resulting from the erroneous ADIRU data.
An engineer colleague of mine was on the flght. He states that the engines were 'cycling' before take-off - pitching up and down.
The take-off itself was 'thrust and drop' and that coming in to land was similar. One of the stewardesses dropped to the floor to pray and when the captain descended, he was in tears.
One of the scary things is that it was blamed on a mobile phone interfering with instrumentation.
The take-off itself was 'thrust and drop' and that coming in to land was similar. One of the stewardesses dropped to the floor to pray and when the captain descended, he was in tears.
One of the scary things is that it was blamed on a mobile phone interfering with instrumentation.
Silly Old Git
Same as the $20 Rolexs Don.
Yup..Thronomister again.
An engineer colleague of mine was on the flght. He states that the engines were 'cycling' before take-off - pitching up and down.
The FAA issued an AD in June 2005 based on Boeing Service Bulletin 777-34-0094 (dated June 10 2004), as they had previously had a report of the display of erroneous heading information to the pilot due to a defect in the OPS (operational program software) of the ADIRU (air data inertial reference unit).
Subsequent to the MAS incident, the FAA has now issued an Emergency airworthiness directive (AD) 2005-18-51 based on the Boeing Alert Service Bulletin 777-34A0137 (dated August 26 2005).
Taken 14 months since the original Service Bulletin to get people to take notice and fix the problem ASAP.
The joke is, this software upgrade is estimated by the FAA to be worth US$65 per aircraft.
Hope this software upgrade in the OPS of the ADIRU fixes the problem.
Subsequent to the MAS incident, the FAA has now issued an Emergency airworthiness directive (AD) 2005-18-51 based on the Boeing Alert Service Bulletin 777-34A0137 (dated August 26 2005).
Taken 14 months since the original Service Bulletin to get people to take notice and fix the problem ASAP.
The joke is, this software upgrade is estimated by the FAA to be worth US$65 per aircraft.
Hope this software upgrade in the OPS of the ADIRU fixes the problem.
Thanks 'Tin'...
I have been told that 1 Thronomister can cope with only 360 deg...
It takes 2 Thronomisters - in series - to cope with 720 deg - so, 370 deg is NO PROBLEM!
NO Thronomisters is a 'NO Go' item I believe.
(TKS 'Tin' ... )
It takes 2 Thronomisters - in series - to cope with 720 deg - so, 370 deg is NO PROBLEM!
NO Thronomisters is a 'NO Go' item I believe.
(TKS 'Tin' ... )
