View Full Version : MAS 777 Emergency

Gyro drifter
1st Aug 2005, 15:12
Hey guys,

Anyone catch the news this evening regarding the grounded MAS 777 at YPPH. They said it was due to a fault in the flight instrument system.

By chance a good mate was onbaord and was told and is 100% sure it was engine failure. Captain lied at first and claimed it was instrument error. Later F/As confirmed my mates thoughts that it was an engine failure. The failure and subsequent turn around happened during the cruise at FL380 just south of YGEL. He said the aircraft pitched up and turned around at same time as begining decent. He was watching the speed decay on the TV display.

Aircraft is grounded over night at YPPH. All pax have been put in hotels and told another aircraft is due to depart again tomorow at 1630.

Very interesting. Would you tell pax it was eng failure or would you make a lie up???

Suppose whenever "eng failure" is said to pax they tend to overreact and are unaware of how bad one really is.


Just another point to look at....

Would you normally expect some kind of a noise as a pax to tell you that the engine has failed before the pilot has cut the fuel feed and subsequently shut her down?

In this case there was no noise. But yet the plane was check after it arrived and has been grounded by engineers.


1st Aug 2005, 15:21
Well, I heard it was a loss of instruments. If that was so, being glass cockpit, then the aircraft could have also lost engine instruments, and would have to fly the aircraft, and set throttles by feel or ear. That could account for change in engine noise and airspeed.

And, if I was a passenger on a 777, I think I would rather hear that one engine failed, than hear that all the instruments failed!!

Also, footage that I saw of the aircraft at the terminal, didnt show any engine cowls open..

However, will find out more when back at work at the tower tomorrow ;-)

1st Aug 2005, 16:05
A reputable airline would never tell the passengers that an engine has 'failed', standard procedure is to say that 'we have had to shut down an angine'.

It could well have been something along the lines of 'instruments on the flight deck indicated that we should shut down the engine, so thats what we have carried out'. This could explain the connection between 'instruments and engines'.

1st Aug 2005, 21:35
Is your good mate a pilot or LAME?

Wouldn't the aircraft pitch DOWN and yaw with an engine failure? I think you would have known about an unexpected failure much more than a checklist shutdown.

But that's just me, and I'm neither of the above ... just working on it. :ok:

Buster Hyman
1st Aug 2005, 21:44
As for telling the pax, well, they were never in danger. Especially if there wasn't a singing Nun, an alcoholic, a sick child on it's way to a life saving operation, a......

1st Aug 2005, 23:54
We were told on descent to Perth that the said acft had control problems. Radio comms also picked up that possible Auto throttle was U/S and the F/O IVSI was not working. They were given Groundspeed cjeck down final by tower.

All dealt with, no big deal....still, didn't stop tv helicopters flying over to broadcast the possible fiery end.

Gyro drifter
1st Aug 2005, 23:55
The mate is a CPL holder. Im sure what he says is correct with what happened. Ie. it deffinetly pitched up before banking.



I think we need some info from someone in the know....



2nd Aug 2005, 00:47
No way one could set thrust by the ears in a 777!!! The cockpit is almost 100 ft from the motors.Only time one can hear the motors is at takeoff thrust and setting climb thrust which give a unique grind. A/T can set thrust in tendem with EEC to give the right speed.

It is possible to decent even just an instrument failure as to get out of RVSM airspace asap.As a result,the reduction in thrust couple with the turn and pitch down would seems like an engine failure. However, in a modern a/c like 777, pax may not even be able to feel a engine failure given amount of technology fitted in the a/c.

Ron & Edna Johns
2nd Aug 2005, 01:28
4 "P"'s in one headline.....! :yuk:

Plane Plunge Panics Passengers (http://www.news.com.au/story/0,10117,16126345-29277,00.html)

2nd Aug 2005, 01:38
wishtobe flying

flt leader is correct. In 777 there should be no immediate, appreciable pitch or yaw. The FBW pitch channel will look after the pitch and the TAC will look after the yaw.

Working properly the A/P will allow the speed to wash off while the crew activate the drift down. When driftdown speed is reached a gentle descent will be initiated. Should the crew fail to execute the drift down, speed will wash off to a preset margin above the stall (about 1.2 VS from memory) and will then descend at that speed until level flt is achievable.

Flt ldr..... they are engines, not motors.


2nd Aug 2005, 02:03
it says in the press release that it was a 74?


Dagger Dirk
2nd Aug 2005, 04:32
A search on Expedia.com shows Malaysian as flying a 727-200 (???) on that route (Perth to KL) as flight 124.

Haven't seen any 727's at Perth in many a year whenever I've passed through.

Ron & Edna Johns
2nd Aug 2005, 05:14
Well, a look at Malaysia Airlines (http://www.malaysiaairlines.com/) shows that they have a daily 772 service and a weekly 330 service between PER and KUL. And I personally have only seen ML 777s and 330s in PER in recent years. Certainly not 747s, and, blimey, 727's....?

"Expedia" rhymes with "media".... and they're both wrong!

Cessna Capt
2nd Aug 2005, 05:21
Ron & Edna Johns

777 and 330 are pretty common down to perth however they were running the 747-400 for a little while instead of the 777 earlier this year and possibly late last year with the 777 comming back recently

CC :ok:

2nd Aug 2005, 07:15
we actually have several 727's a day at perth, though they are the AAE freighters. They are a pleasure to hear taking off though.

I thought someone must have got it wrong in the press release cause most of the international flights through here are the larger twins

2nd Aug 2005, 09:59
Kim Holst, who had never flown before, said the plane began shuddering violently and dropping more than 100m at a time over about 90 seconds.

He must be an ATC radar controller and just happened to have an IVSI, Altimeter and stopwatch in his carry on.:rolleyes:

2nd Aug 2005, 10:13
I wonder if the fella who invented all this IFE stuff would have ever guessed that some spotter would use it to determine rates of climb, or in this case plumet!!!!

Hmm 300 feet in 90secs....might have been my straight and level!!

Have been told by the TVL refueler that you have to get pretty darn low to land a 777.


2nd Aug 2005, 11:00
It was an ADIRU failure and the ATSB currently have in their possession the DFDR and CVR

2nd Aug 2005, 11:56
Certainly seems that way:

=http://perthacars.no-ip.org:8050/acars/search_indiv.asp?r=9M-MRG&d=1/8/2005]Perth ACARS


2nd Aug 2005, 13:38
The mate is a CPL holder. Im sure what he says is correct with what happened. Ie. it deffinetly pitched up before banking.

There is a difference between a mere CPL holder & an ATPL holder with a high performance Jet rating.The main thing is we don't jump to conclusions & slag off another professional.Accusing them of lying is unthinkable too. :mad:

Cool demeanour & calm thinking is a main critirea in this high risk job.This is when we earn the big bucks that we get (not big enough though)

At the end of the day congratulations are in order for a job well done to the crew.Heard through the grapevine that an ADIRU failure occured (which is quite a major problem) & it was handled well by the crew.Kudos guys.

Gyro drifter
2nd Aug 2005, 15:23
Yeh i think you guys are right hey. Looks like it wasnt an engine failure. Ive told my mate he shouldnt trust those damn F/A's.


Not that i give a %&^* but the guy has frozen atpl and a degree in aviation. Knows his stuff for heavy metal.


2nd Aug 2005, 17:54
By chance a good mate was onbaord and was told and is 100% sure it was engine failure. Captain lied at first and claimed it was instrument error.

Not that i give a %&^* but the guy has frozen atpl and a degree in aviation. Knows his stuff for heavy metal.

Gyro drifter, I am just making a point here that if you are unqualified (or in this case unfamiliar with the a/c tech specs), you shouldn't hang a man who happens to be professionally qualified on the said a/c & claimed he lied & you know better.It's just like being a monday morning quaterback & claim you can throw the pigskin better.Having a Frozen ATPL is well & good & knowledge of heavy metal is a plus too.....but is he rated,qualified & flew the a/c that he was travelling in?It's bad enough that journo's get their facts wrong but it's even worse when it comes from a so called 'qualified expert' :confused:

Again, if I made a remark that offended you or your friend, think what it would it be like if you were the skipper & accused of lying.I presume you would be mad too right?

2nd Aug 2005, 19:07
Besides the numerous other things the ADIRU information is used for, isn't it also used by the engine EECs to determine some fundamental operating criteria like fuel flow? Despite the engines having their own ambient sensors, these lie dormant.


Cessna Capt
3rd Aug 2005, 03:55
The following is taken from the 777 flight manual about the ADIRU:

Air Data Inertial Reference System (ADIRS)
The ADIRS provides:
· Primary, secondary and standby air data
· Inertial reference information.
The major components of the ADIRS are:
· One Air Data Inertial Reference
Unit (ADIRU)
· One Secondary Attitude Air Data
Reference Unit (SAARU)
· Eight air data modules
· Six static ports
· Three pitot probes
· Two angle-of-attack vanes
· One total air temperature probe.
Air Data Inertial Reference Unit (ADIRU)
The ADIRU is the primary source for speed, altitude, attitude and inertial navigation position information. The ADIRU processes information measured by its internal gyros and accelerometers, and from air data module inputs, angle-of-attack vanes and other systems. The ADIRU is described in Section 6.11, Flight Management, Navigation.

Secondary Attitude Air Data Reference Unit (SAARU)

The SAARU is the secondary source for speed, altitude, and attitude information. The SAARU processes information measured by its internal gyros and accelerometers, and from air data module inputs, angle-of-attack vanes, and other systems.
The SAARU also transmits roll and pitch attitude information to the standby attitude display.
The SAARU does not provide navigational position data. The SAARU is described in Section 6.11, Flight Management, Navigation.

3rd Aug 2005, 17:02
And I personally have only seen ML 777s and 330s in PER in recent years. Certainly not 747s, and, blimey, 727's....?

whoever made the comment about the 744s, yep, have seen one myself as late as Feb (poss march) this year in YPPH, also on the odd occasion where I've assumed it's a scheduling or maintenance thing requiring them to use a 744...

God, gotta love the 7 network and their reporting of a "747" while showing footage of the 777.. I mean, c'mon, take the 10 seconds to Google it at least.... :rolleyes:

also the pax that was quoted in the West Australian, they headlined something about 'horror flight' etc etc... then the guy says "Some guy (bloding mine) told me the plane plunged over 200ft." someone already asked if the guy had an alitimeter on him (rofl...!) exactly! also they pax assume that the drop had something to do with the problem (likely, but not 100% - it could have been some random CAT or similar....) from all appearances, the aircraft seemed fairly steady and in controlled flight coming in to land... seems as though it's all been blown out of proportion if you ask me....... then again that's not unusual is it? :E

we actually have several 727's a day at perth, though they are the AAE freighters. They are a pleasure to hear taking off though.

4SPOOLED, gotta agree with you there mate! :ok: Especially nice on the early morning departure on one of those crisp mornings where you hear her for ages afterwards! :}

It'll be a pity when they trade 'em in for the 737F's.... then it'll be all twins and little buggers for Perth!!! :p

3rd Aug 2005, 19:08
I was kinda shocked when i read the papers to find out that mas 772 had somesort of emergency and had to return to perth
passengers did say that they felt a sudden drop.

Maybe the aircraft did stalled. if that was the case this is probably what happened.
they took off 40 minutes from perth and cruising at 0.84 mach at fl380.
they had one engine out and engine didn't relight. so they had to shut down one engine and they were at cruise power. Autopilot had to maintain fl380 so it kept raising the attitude and speed is going to bleed of fast if they didn't select mct, aircraft stalls and that's when it alerted all the passengers.
you're at flight lvl 380 and 0.84 mach and ias is probably about 230 knots and aircraft stalls at say about 150 knots clean.

I've never flown a 772 nor have i been up to fl380. the figures i've given is just a logic estimate

3rd Aug 2005, 20:05
caesarlwk, please read my earlier posting about being a monday morning quaterback :}

Modern FBW airliners don't fall out from the sky with an engine failure.There are enough redundancies & some more built in (especially with ETOPS certified a/c) to make sure those catastrophic failures don't occur, let alone a stall condition.

As it is ATSB are on top of things,let's wait for a preliminary report before resorting to second guessing.

3rd Aug 2005, 22:14
Some suggestion going around that it was a result of interference from electronic equipment onboard the aircraft causing problems with instruments and autopilot.

The crew did mention in his radio calls to ATC that they had difficulty controlling the aircraft associated with instrument indication errors.

Been reports that cabin crew went through the cabin to get all passengers to turn off electrical equipment and mobile phones after this occurred.

Well done tot the crew, professionally handled.


4th Aug 2005, 01:32

A pig at the flight control would have reponded to an speed decay from .84 to 150kts!! No airline pilots would stall a jet,especailly a 777.

The pilot would have done a driftdown( high speed descent is more likely in this case) if the engine failed. And the a/c actually would yell out ' ENGINE FAIL' at the crew if the engine R
PM drops below idle.

They may have slight over control the a/c using 3" LCD standbyinstruments instead of the usual big screen PFD/ND.
But the standby intruments are bettter than alot of the AH of other a/cs.

4th Aug 2005, 02:00
Sorry flight leader not quite correct on the eng fail bit.

The eng fail aural and visual message only occurs on the ground below 65 kts, mind you I always get an aural eng fail message from the guy sitting next to me in the sim at any alt:hmm:

4th Aug 2005, 02:39

I see your logic to thinking how the A/C stalled, may be true in a lighter cousin, but not in a 777 of all things.

a engine failure wouldnt even bother the thing, but an electronic failure might. hmmm tape on the static vents?

4th Aug 2005, 04:56
About two [alright, three] words into caesarlwk's post and I decided he was taking the piss!:D

He still got a few bites!:8

4th Aug 2005, 05:40
Just to give you guys a perspective of the local Malaysian rags :

The Malay Mail:

High anxiety 30,000 feet in the sky: Top flight heroes
Eddie Chua
KUALA LUMPUR , August 4:

They are the heroes. The pilots of Malaysia Airlines flight MH124.
Capt Norhisham Kassim and first officer Caleb Foong took over the yoke (control column) to fly the Boeing 777-200 manually after a glitch in the flight control computers.

MH124 with 177 passengers was 25 minutes into a flight from Perth to Kuala Lumpur when the computer glitch deprived the pilots control of the plane.

“At 30,000 ft, quick response was needed. The pilots had the guts and skill to take control immediately,” said an aviation source. Australian aviation authorities are investigating the incident.

“By taking control of the flight manually, the pilots prevented the plane from stalling and averted a disaster,” the source told The Malay Mail last night.

The two pilots who manned the Boeing 777-200 cockpit “had to wrestle the switches and gears on the control panels to steer the aircraft back to position in split-second decisions and they successfully stabilised the situation,” added the source.

The plane was cruising at a speed of about 850 kmph, over the tip of the northern Australian coastline, when the incident occurred. Up to this point, the passengers were blissfully unaware of the problem. Even when Norhisham announced that they were returning to Perth, most thought it was just “one of those things”.

The high drama at 30,000 feet got more intense when the plane ploughed into turbulent winds, including a ‘wind shear’ (localised change in wind speed and, or direction over a short distance). This caused the plane to wobble and plunge some 200 metres.

Panic broke out in the cabin, with passengers hanging onto their seats, some crying and saying their prayers.

“The pilots had to use all their skills to guide the plane through the turbulence,” said the source.

It is learnt that Norhisham has more than 20 years of flying experience. He has been piloting Boeing 777-200 for more than five years.

The source said the pilots radioed Perth airport and requested for priority landing.

“The air traffic controllers were constantly in contact with the pilots, monitoring their flight path on the radar screen and verifying their positions, every now and then, to guide them back to the airport,” the source said.

The pilots landed the plane at 5.38pm — 51 minutes after leaving the airport.

The pilots, said the source, filed a report with the Australian Transport Safety Bureau (ATSB). ATSB officials have interviewed Norhisham and Foong.

The plane’s black box was also removed for examination. The black box will provide an insight into how the incident occurred and what transpired in the cockpit during the glitch.

The source declined to say if Norhisham and Foong have returned to Kuala Lumpur or are still in Perth to assist in the investigation.

The News Straits Times:

Passengers cause of plunge?
Tony Emmanuel


Passengers using electronic gadgets could have been behind the technical glitch that caused a Malaysia Airlines aircraft to plunge 200 metres on Monday.
The New Straits Times has learnt that shortly after take-off from Perth, there was interference in the cockpit display and failure of the wing flaps.

Suddenly the aircraft started losing altitude and cabin crew made several appeals to passengers to ensure electronic equipment was switched off.

The Boeing 777 plane began shuddering violently and dropped about 200 metres over a period of 90 seconds.

Several of the 177 passengers on board panicked after one steward dropped a tray of drinks and another began praying.

Aviation engineers from aircraft manufacturers Boeing and Australia’s Civil Aviation Safety Authority were studying the flight data recorder of MH124 to know what transpired prior to the incident.

"At this moment, what has been concluded from the flight data recorder is there were discrepancies which seem to be electronic in nature," aviation sources said.

So far, it is highly probable that there was an electronic magnetic interference.

A Malaysia Airlines Pilots Association official said today:

"While it may be premature to conclude what transpired after the Perth take-off, our repeated announcements before take-off were not without reason.

"The aircraft’s control interior is a glass cockpit... all electronic flight instrumentation system is displayed on a monitor like a television screen."

International aviation regulations make it mandatory for cellular phones to be switched off when passengers board aircraft.

"What many fail to realise is that there are portable compact disc players, computer notebooks and portable games that can cause electronic magnetic interference," the association official said in a statement.

The Star

MAS plane in Perth drama grounded


PUTRAJAYA: Grounded. The Malaysian Airline plane that sent 177 passengers reeling in panic during a flight out of Perth on Monday will not fly for the time being.

“I must say MAS has done the right thing to ground the aircraft and to seek assistance from the Australian authorities to run thorough checks on the plane,” Transport Minister Datuk Seri Chan Kong Choy said.

“We will not fly the aircraft until it is certified safe. We need to ascertain the reasons (for the incident),” he told reporters after a post-Cabinet meeting here yesterday.

The Boeing 777-200 craft plunged some 200m in the air just 40 minutes after taking off from Perth international airport at 4.47pm.

The pilot of the Kuala Lumpur-bound MH124 flight detected an engine malfunction during the initial cruise and turned back. He landed the aircraft safely at 5.38pm.

Capt Norhisham Kassim, who earned praises from the passengers and crew for his handling of the plane when it was in trouble, has since given a report on the incident to the Australian Transport Safety Bureau.

Chan said he had received a preliminary report on the incident and praised MAS for “taking the right step”.

He said that until the aircraft was certified safe, MAS would ground the aircraft in Perth.

On the ill-fated helicopter crash on July 25 that killed three people in the hilly jungles of Kapit, Sarawak, Chan said he had also received a preliminary report on the accident.

“We still can’t establish the main reason for the crash,” he said, adding that the Cabinet discussed the matter during its meeting.

Survey and Mapping department technician Razali Hassan survived the Hornbill Skyways Bell 206 crash but his colleague Ramli Jamal, pilot Capt Razali Sani and army corporal Empeni Karong died.

“The sole survivor will help us in the investigation but on the mechanical side, it will take some time as we need to seek assistance from experts,” said Chan.

He said officials from his ministry and the Department of Civil Aviation would meet the state government and relevant authorities to find out the best way to avoid such accidents.

“One reason, I think, is the high terrain and mountainous range as well as the strong winds throughout the year.”

Asked about the haze, he said all airports were being closely monitored but, so far, visibility was still good.

king oath
4th Aug 2005, 06:00
The Malay Mail no less.

I wonder if these imaginitive journos ever worked for the NT News. If not there may be a job opening for them in Darwin.

4th Aug 2005, 07:49
Seems they are just a bad over there. Maybe worse.

Why don't we all make a protest and don't buy a newspaper for a week! Better still 'ever'. I don't. Donate the money to a worthy charity like the RFDS instead.

Mind you they do provide some sheap humour!!:}


Gyro drifter
4th Aug 2005, 08:59
Yes all very interesting....

Got some more news on the incident. This time its straight from pilots themselves.

Seems they simply had a problem with the autothrottle and had to disengage and hand fly all way back down to YPPH.

Dont know where you guys are getting this ADIRS failure from. The engineers are still looking at the problem as far as I know.

Happens this friend went back the next day to fly MAS and was seated 1 row behind the pilots from the incident. A quick 10min chat revieled this info.

4th Aug 2005, 14:01
The mystery is solved. So the pilots were forced to fly the aircraft manually sans autothrottle. Jesus wept! that must have been a real Mayday situation having to fly maybe even raw data. No wonder the pax were relieved when they landed - it must have been absolutely frightening for the poor possums. Award the captain an immediate AFC.

4th Aug 2005, 21:48
My Auto throttle never works either!!!


5th Aug 2005, 12:24
Gyro, Have a look at Pungents posting, I think he is more in the know than your mate in row 2A.

7th Aug 2005, 17:18

The pilots are not at liberty to discussing it with anyone so they have played it down for your friends benefit. A/T u/s would not have warranted any air turnback.
Lets just leave it for the official findings before making any more assumptions and guesses before that.FYI so far all your sources have been wrong...whatever degree they have or seat they are in.The truth will be out soon...and the posts on instruments failure(ADIRU) is more accurate.


Buster Hyman
8th Aug 2005, 04:48
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
Crikey! Those things are like lightening!

9th Aug 2005, 06:56
You beat me to it Buster! :rolleyes:

9th Aug 2005, 18:15
Several of the 177 passengers on board panicked after one steward dropped a tray of drinks and another began praying.
I'd be praying too if the steward had just dropped my Johnny Black and Dry!
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. :O

10th Aug 2005, 09:03
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.

11th Aug 2005, 12:28
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.....


11th Aug 2005, 12:43

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.


12th Aug 2005, 00:11
The following was released by Boeing not so long ago. It seems to relate to the incident being discussed in this thread.


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.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


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

Hope that clarifies things for some people.

14th Aug 2005, 07:14
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 :mad:

Btw, here's what the local rag published recently:

The Malay Mail

Nerves of steel in mid-air save 193 lives
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..... :p

Capn Bloggs
14th Aug 2005, 07:24
SAARU data by the PFC reduced the severity of the pitch-up resulting from the erroneous ADIRU data.
Without the SAARU, it would've been loop-the-loop, I suppose! :eek:

31st Aug 2005, 06:23
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.

Don Esson
31st Aug 2005, 06:32
"He had also asked to maintain the flight at 370 degrees."

Intersting compasses used by Malaysian??

31st Aug 2005, 06:35
Same as the $20 Rolexs Don.

An engineer colleague of mine was on the flght. He states that the engines were 'cycling' before take-off - pitching up and down.

Yup..Thronomister again.:hmm:

31st Aug 2005, 07:00
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.

31st Aug 2005, 10:34
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.:ugh:

(TKS 'Tin' ... )