AirAsia flies to Melb instead of KL . Navigation error

[compressor stall]

No but if we ban them they ban us. And we need their airspace to get anywhere more than they need ours. Same for Indo.

[gazumped]

Wow! And this happened 15 March last year. This should be being shouted from the tree tops by our press. How do the paying public get on these aircraft?

It seems the over-riding modus operandi of some airlines is: IF THE AUTOMATICS FAIL THE AIRCRAFT CANT OPERATE.

Let alone all the warnings this crew overlooked to get airborne in the first place. the operational decision by this airline to allow the same crew to continue to their original destination, beggars belief!

How can anyone describe Raw Data as a "dire emergency"?

I say again Wow!

[BuzzBox]

Ben Sandilands is on to it, although I doubt that very many of the 'paying public' read his blog:

ATSB reports on cockpit cockup in AirAsiaX flight to KL

[flash8]

It could have been worse... put them in a clockwork airplane and they would have ended up in London..

attempt to realign the IRS's in the air.

wtf.

[deadheader]

Dodgy earmuffs => u/s GPWS

Could easily have led to more than just tea & biscuits, e.g. mountainous terrain IMC etc

[n5296s]

Sad story. But why were they entering coordinates in the first place, rather than airport designators and waypoints? (Not to mention the bit about them reading them from a piece of card held in front of the aircraft - reminiscent of Three Men in a Boat).

And why did entering the wrong coords cause a terrain alert?

Luckily this just turned into an amusing story. But I wouldn't be in a big hurry to fly with Air Asia.

[wiggy]

why did entering the wrong coords cause a terrain alert?

Unless the EGPWS was solely using GPS data I wonder if it was a predictive warning, based on the corrupt position?

Edit to add, having just dug into the report:

"An EGPWS alert activated at approximately 600 ft during the initial approach at Melbourne,
seconds prior to the commencement of the go-around. An assessment of recorded parameters
indicated that, as with the EGPWS alert departing Sydney, this was also a spurious warning
associated with the aircraft’s incorrect position information."

[Herod]

I think the EGPWS thought they were heading for Table Mountain. Without looking at it, I would suggest KL is a track in the region of 320 degrees. Actually about 298, but my guess would have had the aircraft going in the right direction. Set heading on the a/p, continue climbing, and sort it out when time permits. Or have ALL the old, basic skills gone?

[GordonR_Cape]

Cape Town is 18.5E, 15E is far out in the Atlantic Ocean, and flying SW goes even further offshore (nowhere near Table Mt). The lack of airports matching that location in the database would be more likely to trigger a warning (with gear down).

A rather similar navigation error (insufficient decimal digits) in Brazil in 1989 led to a much less happy outcome: https://en.wikipedia.org/wiki/Varig_Flight_254

[PAXboy]

The ATSB said “even experienced flight crew are not immune from data entry errors” and advised AirAsia to upgrade its flight systems to assist in preventing or detecting such errors in future.

Does this indicate that the ATSB think it better to make the machine smarter - rather than attempt to make the crew smarter ...? Had it have been QF/or other, might they have said something different?

[springbok449]

Faulty earmuffs? Seriously is that the only excuse they could come up with? Sounds more to me like the skipper didn't fancy doing the walk around in SYD because of the bad weather...

[peekay4]

Does this indicate that the ATSB think it better to make the machine smarter - rather than attempt to make the crew smarter ...? Had it have been QF/or other, might they have said something different?

ATSB is saying that it's impossible to 100% eliminate human error.

The Captain who made the initial data entry mistake had over 22,500 hrs. No matter how experienced you are, people must be expected to make mistakes at some point. There must be cross-checks, and in this case human & automated cross-checks / procedures all failed.

While both pilots' performances were inadequate, there were also numerous issues with the Airbus system:

• When there's GPS and IRS disagreement, the GPS position is supposed to be invalidated and a GPS NAV FAULT warning should have appeared on ECAM. But this warning was never displayed.
• Similarly, upon entering the wrong IRS coordinates, a separate FMS/GPS POSITION DISAGREE warning should have activated. No evidence that it did.
• When takeoff thrust is applied and GPS PRIMARY is not active, the aircraft coordinate is supposed to auto-update based on the entered runway location. But this didn't happen either; the update just silently failed.
• And instead of flagging the bad data, the system displayed the wrong magnetic heading to the crew on the ND and PFD. After takeoff the displayed heading was 193 degrees when the actual heading was 155 degrees. So they turned left to intercept the SID instead of turning right like they were supposed to.
• On a couple of occasions there were warning chimes, but without any ECAM messages or indication of what (if anything) was actually in error

I'm sure software updates are being made...

[peekay4]

How can anyone describe Raw Data as a "dire emergency"?

Nothing to do with raw data. They had the wrong heading displayed on both ND & PFD due to incorrect magnetic variation being applied, so they were unknowingly flying the wrong way even when they tried to follow ATC instructions. That could have been disastrous.

But why were they entering coordinates in the first place, rather than airport designators and waypoints?

We're talking about two different things here. Airport designators & waypoints are entered into the flight plan in the FMGS. The crew did this part correctly. The coordinates are needed to update the IRS and require greater precision. The crew did this part incorrectly.

[Herod]

The lack of airports matching that location in the database would be more likely to trigger a warning (with gear down).

GordonR. Yes you're right, I hadn't thought it through properly. I had just that when flying into a new airfield in Africa. Night-time, perfect vis, runway lights in sight. EGPWS started blaring, because it thought we were trying to land in the desert. SOP at night? Go-around. That would have gone down well with management.

[Enos]

Didn't Polish LOT do something very similar in an old generation 737 possibly a 400 out of LHR.

Entered East into the FMC because that's where they mostly do all their flying on the 737, instead of West and with the IRSs not working correctly your down to STBY instrumentation.

ATC talked them down with turn right 5' left 10' etc.

We are all sky gods at home on the couch but are all just one flight away from a Disaster at work!

Correct me if I'm wrong gents.

Cheers Enos

[peekay4]

Yup: http://www.pprune.org/rumours-news/3...sh-blamed.html

[atlas12]

Did the FO even check the FMC entries before departure I wonder? And why did the skipper manually enter the lat/long into the FMC from the sign at the gate? At my company we just copy the GPS coordinates and verify them against the airport/gate reference from the database or JEPS if required. I have stuffed up lat/long waypoint entry before on a long sector with about 10 manual waypoints to enter because ACARS didn't download them, but this is why the second crew member checks the FMC. The error was detected during the LEGS check and it turns out I had some finger trouble during entry and the waypoint was about 50 miles off track very stupid on my behalf and I learned a valuable lesson that day, now I go over my own work with a fine tooth comb before passing it over to the other guy. Having said that, departing with an incorrect alignment in this day and age should be impossible and ignoring all of the warnings is just insanity

[ImbracableCrunk]

Originally Posted by RAT 5

Not to mention that the view out of the side window after 400' is not what was expected.

In my experience in Awesome Asian Aviation Excursion, the ground doesn't exist above 400' AGL.

[NSEU]

They had full VOR and ILS capability and could easily have flown the approach back to Sydney. I guess not having a magenta line scared them.

Sydney now has no VOR. Also, the magnetic heading data fed into the VOR systems is based on IRU present position (which appears to have been wrong). I'm surprised the aircraft reached Melbourne with vectors (unless they were using their whiskey compass).

Turning off intertial reference systems at the wrong time hasn't only happened to budget airlines.

[CurtainTwitcher]

One very subtle point that I've found is that alignment of the IRS on my aircraft calculates its own latitude as a reasonableness check, but not it's own longitude. The manufacturer FCOM is very hazy on alignment and error codes (none are listed any more).

However, a well known third party publication states:

Reasonableness tests
- The IRU compares entered long with the last LAST POS stored in non-volatile memory
-The IRU does not calculate its own longitude
-If the the difference you enter is greater than 1°, the ALIGN annunciation flashes, status code 4 shows and ENTER IRS POSITION displays on the CDU
-This could legitimately occur (i.e the entry is correct if the IRU was newly installed
...

The IRU also compares entered latitude with the LAST POS latitude
-The IRU calculates its own latitude
-If the difference is greater than 1°, the ALIGN annunciation flashes

This failure mode (for us humans) is very subtle.

however

I was unaware of this subtleties until this thread forced me to have a greater look at my own system knowledge and defences. The FCOM would not lead you to this understanding, and that is quite a large hole in the Swiss cheese.