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Thanks searchingheaven for creating this thread, IMO this is undoubtedly one of the best threads out here in the recent past.

Since there are quite a few aviation experts here, can someone explain how this happened? Looks like this is an incident from last year but the official report was out this week. The headline used is clickbait as they couldn't land in SYD because of bad weather, but how severe and frequent is this incident of the pilot keying in the 'wrong longitudinal position' and not realising it until later?

If this thread isn't apt for non-777 queries, please guide me to the relevant topic.

P.S.- Flying on the 777 with TK two weeks later :)

I Would say it is very rare indeed. Im not even sure what happened here, but then Im not really that familiar with Airbus systems.

Planes do occasionally land on the wrong airport. But usually thats because two airports are close together, similar runway orientation etc.

These guys got it wrong more than 10-11.000 km.
What i cant even begin to understand is how they managed this flight without ATC telling them what to do!

On the 747-400 (probably the 777 as well) when you hit the TOGA button for the take off, the flight management system gets updated with the actual geographical position, based on runway threshold and GPS position.

Jeroen

Jeroen

Same is true for A330/340. Apart from the Qantas flight 72 incident, none of the accidents/incidents is attributed to a fault with the aircraft itself.

777's contemporaries, the A330/340 cousins also have a stellar safety record. Most of the modern airliners are much safer than their predecessors and every accident has been a lesson learned in aviation.

https://www.quora.com/Which-one-is-s...Boeing-777-200
http://www.fearofflying.com/resource...e-safety.shtml
https://en.wikipedia.org/wiki/List_o...he_Airbus_A330

Here the report on the AirAsia flight that landed at the wrong airport

https://www.atsb.gov.au/publications...r/ao-2015-029/

Looks like they made a data entry (position) entry error and did not realise it, until airborne. Whilst trouble shooting things became even worse. As the weather had worsened they could not return to Sydney and decided to divert to Melbourne.

ATC was on top of it from the moment they left the ground. (which would have been extremely odd if they hadn’t )

The normal Airbus procedure for initialising the position of the Flight Management system is to enter the relevant gate. (Similar to the Honeywell system on Boeing)

I thought, I might be wrong, that the above is to give the Inertial Reference System its reference? You would still have your various (three) GPS systems too. If GPS and IRS don’t agree you would expect some sort of notification?

How come their ND did not present them with some clues as to where they were going, their flight path etc.

Maybe one of our residential Airbus drivers can shed some light on this?

Jeroen

Surprising indeed! In this age of technology where even car GPS systems are getting accurate location information and guiding the driver to the destination, why would a pilot be required to manually input the present location, that too on the ground?

Its a bit more complicated then that. On these sort of planes there three independent means of navigating. GPS, IRS (inertial reference system) and by means of ground based radio stations such as VORs.

There are usually three GPS and three IRUs. Inertial reference unit. Each GPS is capable of providing you with a geographical position. IRS is different. You need to tell it where it is. From then on it measure de- acceleration and can calculate your position. It is very reliable, not as accurate as GPS, it has drift, but it doesn't rely on external sources at all.

All these different systems and their subsequent measures are thrown together and some clever logic figures out what the most reliable reading is. (Obviously, i am simplifying a bit)

That final outcome is presented to the pilots, drives various displays and annunciation. It looks like they made an error in the entry for the reference position for the IRS.

We take if for granted that planes fly//navigate by means of GPS these days. That is only partially true. Also, GPS for many years wasn't allowed as means of primary navigation on commercial planes whereas it was used for many other applications around the world. On the little planes I fly, GPS was allowed as primary navigation source years before it kicked in for commercial aviation.

Most pilots will tell you that the logic as I described above is more or less a series of binary steps. E.g.if GPS is the most accurate use that one. If GPS fails, check IRS and VOR, determine most accurate and switch etc.

Again, I'm not familiar with the Airbus system. But some 10 years ago I studied this logic in great detail on the Boeing 747-400 helped by a KLM technician friend of mine.

In fact the system never flies/uses only GPS. It is a GPS position complimented with information from IRS and other sources. Probably as GPS technology has advanced a lot as well, it might be a hundred percent these days on modern systems.

If you click on the link I provided in my previous post and then look under context you will find am interesting technical,overview of these various navigation systems on an Airbus
Jeroen

The TOGA position update is only available when GPS updating is "Off", else TOGA updating is ignored. It is GPS that provides the position on ground. In flight, the system has a internal logic for position update between GPS, IRS and ground radio aids depending on many factors.

It is very rare indeed!! The system has many internal comparison tests that needs to be passed in order for the system to accept the position you enter. It gives error messages if the self tests fail. It is hard to ignore as,in many cases the Inertial system will not all align in case of fail in the self test. However, if the same ( incorrect)position is reentered, then the system may accept it and continue with the alignment. The reason that I say "may accept it" is because the second test compares different set of parameters like just the latitude, for eg and if that test is passed then the system continues with the alignment. Having said all that, enough warnings are presented to the pilot indicating that the system believes that there are inaccuracies in the position. Please note that these error and fault alerting are airplane specific and it may be different in the A330.

You are correct. I was looking into one of my old KLM 747-400 AOMs. It was pre GPS. So I guess then it would always do an position update when you push TOGA.
I hadn't realised some of my manuals are that old! Pre-GPS

Jeroen

For the accident at Dubai, I think the final report would lay most of the blame on the pilots.

Nowadays , in the Middle East the weather on the ground is very hot. The ISA deviation is +30. At such high temperatures , the air density is low.

When, you are coming in to land, the thrust settings are low. When the wind is a headwind( the good wind for take off and landing), it increases the performance of the aircraft. As an example if the aircraft has a approach speed of 150 KIAS( knots indicated air speed), the headwind reduces your ground speed ( reduces your landing roll, i.e. distance required to stop). The aircraft has to fly at certain speeds w.r.t the air around it to be stable. The headwind acts as if the aircraft is flying faster( at the same Indicated Airspeed if the wind is a headwind the True airspeed of the aircraft is slower which is good for both take off and landing). If this headwind quickly changes to a tailwind it becomes what is called as windshear. Now , instead of helping with the aircrafts performance on the contrary the tailwind is degrading the aircrafts performance. To achieve the same indicated airspeed the aircraft has to suddenly fly faster to negate the negative effects of the tailwinds.

Now, if all this happens at low altitudes when the airplane is already in a low momentum state, with thrust settings on the lower side, the time for the pilot to act is very little. An undesirable situation could quickly lead to a critical situation unless counteracted immediately by the pilot. In this case the only option was to apply maximum thrust and abort the landing. On Boeing aircraft there is a button on each thrust lever which is called TO/GA ( Take Off/ Go Around). This button is pressed during the Take Off and the Auto Throttle moves both the thrust levers to the desired thrust settings. The same button is pressed during an aborted landing( also called Go- Around or missed approach), which again moves the thrust levers to the desired thrust settings. Notwithstanding , when you press this button, it is imperative that you check that the auto throttle has actually moved the thrust levers , if not then you can manually advance the thrust levers to the desired setting. We use auto landing in Delhi during the winters when the visibility is low.( upto 50 metres CAT 3B). One of the common exercises in the simulator is practising the TOGA failure during a critical time. This failure is of two types. One in which the entire TOGA system fails and the more tricky one in which you press the TOGA switches and the Flight Directors command a certain pitch attitude but the motor running the TOGA switches has failed. In both cases you are expected to manually advance the thrust levers. So, in the case of the Emirates aircraft even a TOGA failure of the aircraft at a critical juncture should have been handled by the pilots, as all the pilots are trained to do so.

I have flown in to Dubai and other cities nearby many times after that accident. You just have to be very careful of the environmental factors at play. The good thing is that the aircrafts are fully capable of handling any and most kind of scenarios if handled correctly and timely by the pilots.

I just held an AMA(Ask me anything) session on Reddit r/India (Link to thread). You will find some interesting questions and answers over there. This session will continue over the next day as well. So you can ask questions which you think may not be appropriate on T-Bhp.

PS: Lurkers on this thread, I have copied some info/answers from this thread directly over to reddit as well.

Going by the sentiment, the "blame" would rest on the pilots then?

In such cases where there has been an accident mainly due to pilot error, what kind of consequences would this have on the pilot/co-pilot? Would it be just the pilot commandeering the landing or both?

How much do total-loss/repairable damage, loss/no-loss of life play a hand in the consequences? And are these consequences at the discretion of the airline/investigating bureau or is there an industry standard (the way we have Sections under the law)?

Thank you for being so patient and forthcoming! :)

What is the procedure if your roster says you need to land at an airport where you've never landed before? Do you undergo simulator tests for those airports?

Interesting question and I'll be interested to hear from the Pro's.

Purely from a legal point of view, unless there are very specific airport specific requirements (E.g. Leh?), pilots are typically qualified to land on any airport. There might be additional requirements around landing with limited visibillity etc. (ie. CAT landings)

I also think it might differ from carrier to carrier. I know KLM used to ensure that always one of the two pilots was very familiar with the airport. Especially very busy airports. AA and United used to have (might still do) special courses for airports such as Atlanta and Chicago.

Or the old HongKong airport. Pilots used to train for that on the simulator and one of the cockpit crew would always have lots of experience.

I can land my single engine plane on any airport I want as long as I'm able to comply with local airport regulations, which I always can.

Whether it's very clever and or safe to do so, is something different. I have landed at very busy and very complex Chicago in one of my little planes.

But I had a friend with me, who was a retired AA Captain who used to have Chicago as his home base. We spend a whole Saturday going throught all the specifics around Chicago airports, procedures (using the AA trainings materials!) and then on Sunday morning we went there. My old flight instructor and another pilot friend came along. Because it is hugely interesting to land at a busy complex airport.

Even something getting a taxi clearance is very different from any other airport I have ever been.

Part of your flight planning will always be to go through the particulars of the destination airports and possible alternates you have.

One of my routines used to be to check on google maps using the satelite view to get some sense of how it looked, in particular looking for forced landing spots (i.e. if the engine stopped unexpectedly). Also Microsoft Simulator used to come in handy to familiarize yourself as a private pilot with an unfamiliar airfield.

It can be very challenging, but very rewarding! Loved it!

It's not just the airfield but also the whole of the airspace in that particular area which can be a huge challenge. Probably more so for Private Pilots than the Commercial Pilots. Especially flying VFR (Visual Flight Rules) compared to IFR (Instrument Flight Rules). Flying around the Washington DC area is really complex with endless restrictions and rules and regulations where you can and not can go. Requires very carefull planning and I for one would never fly there by myself without having somebody with me, who is very familiar with the airspace and has flown there repeatedly. (But legally there is nothing that would stop me flying into Washington DC, no formal training or certification required other then my Private Pilot License and the ususal regular paperwork in order)

Jeroen

Sorry for the delay guys. In general, most commercial pilots are familiar with the airports they fly to. In case the airport is unfamiliar, we use simulation software and company's videos to get an idea of the terrain and the approach. Personally, company simulation time on level D simulators is very hard to come by. So I use generic simulators to get an idea of the airport before I actually fly them.

Some specific airports require specific landing certifications clearance, eg. Paro, Bhutan. Apart from airports, some areas require you to go through specific training in case you are VFR, for eg. Washington DC has something called Special Awareness Training.

Even from a legal POV, VFR pilots require ALC-405 course completion certificate to fly in the restricted area of Washington DC.