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Mid air collision of two aircrafts taking off simultaneously averted in India (thehindu.com)
68 points by reacharavindh 10 months ago | hide | past | favorite | 45 comments

Not only was this a serious lapse in critical infrastructure, they did not even bother to report it! > “None of the entities involved shared the information. It was during our surveillance that we discovered that this had happened,” the DGCA source said.

This industry relies on self-reporting, there's no sky police, so if there's a deviation a report needs to be voluntarily written up and submitted either by the controller or by the pilot. It's customary for pilots to self-report on their deviations whether or not they were requested to do so and I'd assume controllers are supposed to do that as well. I'm guessing this trust is broken every now and then.

The pilots probably weren't aware of the close call so it's not like they're going to tell the controller to write a number down. The controller would probably be the only one that knew and should have written a report about it. But the article is talking about going after the airport authority and the airline, as if the pilots or controllers (the only ones responsible for writing the report) actually did their report but it was ignored and was never escalated properly to the higher authority?

>I'm guessing this trust is broken every now and then.

I'm guessing who you work for has a big influence on how much trust there was in the first place.

The reports don't go to your employer, at least in the US. ASRS reports[0] go right to the FAA and pilots are incentivized to submit them - it's not a get out of jail free card, but if you're contacted for enforcement/education later, it's a huge mark in your favor to be able to pull up an ASRS number (that you get when you submit) and say that you submitted one thirty minutes after the incident. I've spoken to one or two pilots who have had the FAA drop an enforcement action after providing them the number.

[0] https://asrs.arc.nasa.gov/

I don't recall if I've heard directly from pilots who have had enforcements dropped when self-reporting to the FAA - my brief time as a student pilot was 20 years ago.

But what I do recall is a culture of risk reduction, working the problem, an "If you see something, say something" mentality.

Then again, everyone has stories of encountering errors that had become part of someone's routine. You don't run to the FAA, you ask questions. There are tough calls, sometimes.

Every pilot has made potentially fatal mistakes. Every living pilot has caught a mistake before it caused an uncontrollable situation, or got lucky. Usually a bit of both... but the luck runs out.

This includes the airliner as well, IndiGo, the largest in India, run by a publicly-traded company.

The pilots of the aircraft involved don't have the situational awareness to understand this kind of issue - I would guess all they know is that they took off and suddenly got expedited vectors away from their original clearances.

The thing that’s unique about this airport is that it has parallel runways, which is very common, but the R runways (right side on approach) do not have right traffic. They also have a left traffic pattern. So two planes taking off at the same time will both make a left turn. Very unusual and very dangerous if you happen to have that situation.

Thank you. Looking at the satellite picture, the runways seem to be sufficiently separated for simultaneous departures and the article did not have a lot of detail. It seemed to be implied that the aircraft were at risk of colliding, but I was unable to see how that was likely. If both runways make left traffic (why?!), that certainly explains it.

It’s really odd. If they use the 09 runways and the 27 runways (depending on wind on any given day) then you have left traffic in the pattern on the north or south side. It could be some weird compromise with the neighbors about only having traffic on one side at a time. I really have no idea. But noise abatement in urban areas is a big deal so if it’s not geography the I’d guess it’s noise. I’m just a private pilot so maybe an ATP here can weigh in. I’ll ask around.

For a counter example look at Centennial in Colorado (KAPA) which had a similar setup and is my home field. They always have right traffic on one of the runways.

The airport in Bangalore is 30miles from the city. It is literally in the middle of nowhere.

There are few settlements nearby ofcourse, however no high density or large group of people or high rise buildings etc.

There shouldn't be any need for noise abatement

My guess is there is something in right traffic that they aren't allowed to fly over, or there is terrain/tall buildings potentially making it dangerous in inclement weather

I had a quick look at the departure charts and they seem to be avoiding an airforce base.

Thanks for that, I was wondering what the layout was since the description seemed incomplete. These sound like minor things, but they are really critical and require coordination.

The article doesn't mention why there can't be parallel takeoffs. Does anyone know why? Looking at the airport on Google Maps it appears there's quite some space between the runways. Perhaps the required flight paths after takeoff intersect?

According to the International Civil Aviation Organization, parallel simultaneous takeoffs are allowed only when the distance between the runways is at least 760 m, a suitable radar is available and the flight paths diverge at least by 15° after departure.[0] Probably at least one of these requisites was not fulfilled in this case.

[0] https://www.icao.int/Meetings/AMC/MA/Eleventh%20Air%20Naviga... pp. A-24 and A-25.

From what I have read, the problem here was that there are two separate tower controllers for the north and south runways; there was a shift change and some kind of confusion over which of the runways was actually operational. The result was that the two tower controllers were not coordinating traffic at all.

EDIT: Kempegowda International Airport is the main airport serving Bangalore, by the way - I noticed the article assumed the reader knows that, and it's probably not general knowledge for the HN audience.

>> The article doesn't mention why there can't be parallel takeoffs.

Another commenter here said both runways use a left traffic pattern, so both aircraft will turn left after takeoff rather than each turning away from the other. That was curious to me as well, but it's also not pertinent to the incident because one was closed at the time.

See my comment about parallel runway traffic patterns at this airport.

I am still surprised that air traffic control is mostly managed by human operators. Seems odd that this cannot be fully automatised and managed through an algorithm.

Like so many things in the world, it's a legacy system that "works", therefore it's extremely difficult to dislodge.

It's pretty clear that ATC at all levels would work far better if fully automated, with staff around to manage emergencies and older aircraft. It's one of those tasks which is very stressful for humans but basically trivial for a computer given the correct parameters (including weather, etc).

It only seems trivial to ignorant, arrogant software developers who don't know anything about aviation.

Thank you. The parent comment screamed of software engineer elitism. Situations change ALL the time in aviation, sometimes in seconds, there are so many externalities. Language is by far the best way to handle them (something computers are terrible at). You don't want the pilot having to read a text output in the middle of a landing approach in bad weather, much less have to type to ask for clarification from ATC or ground.

I saw a video the other day of a student pilot that had very light experience (I think this was his second lesson or something like that) and had to perform an emergency landing on his own because his instructor passed out. He would’ve not been able to do a guided landing without ATC. Really short sighted to think that a software based automated system could replace controllers.

There is the question of liability management. If something bad happens due to an edge case in an algorithm, and people die, who is responsible?

With an algorithm, you are placing responsibility on something you cannot blame.

Not popular in situations where human lives are at stake.

A human operator, with such a responsibility, will develop and sustain skills to handle any edge case.

Sorry to be pedantic but for non-native speakers interested in correct use of the language I just want to point out that the correct plural of aircraft is aircraft. It is an uncountable noun. "Aircrafts" is not traditionally considered a valid word and is guaranteed to raise eyebrows from educated native speakers. Wiktionary (the most permissive and holistic dictionary available) lists it, rather politely, as a (nonstandard) plural of aircraft. Cambridge denies it exists: https://dictionary.cambridge.org/dictionary/english/aircraft...

@dang can we drop the "s" please.

I think these kind of incidents are "averted" on a daily basis. It's just that air traffic controllers don't share that information every time. There's a great deal of near-miss incident at many airports around the world. But we don't hear about it.

I'm going to argue against you. The airline industry does have a culture that encourages even the slightest incidents to be reported, analysed, and protected against in the future. There are multiple youtube channels (Mentour, VAS aviation for example) that collect large numbers of these and present/explain them very well. That this particular incident was swept under the carpet until someone else noticed it would be shocking to a western pilot or controller. In fact, it seems from the article that it was shocking to the person who did discover it.

> I'm going to argue against you. The airline industry does have a culture that encourages even the slightest incidents to be reported, analysed, and protected against in the future.

The airline industry in some countries may have that culture. In some countries it may not.

The societal culture may 'override' the workplace/industry culture:

> Executives of South Korea’s Asiana Airlines say they’re altering its pilot training program to encourage communication among senior managers and subordinates, after a July plane crash in San Francisco that killed three people and injured dozens.

> A U.S. hearing into the crash revealed one of the pilots said he did not feel he had the authority to abort a low-speed landing as individuals at a “higher level” had to make that decision.

* https://www.cnbc.com/2014/02/10/asiana-airlines-to-pursue-co...

* https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214

> A culture that frowns upon crew resource management: the pilot flying the airplane was senior in rank and stature to both the instructor pilot and copilot who would have been reluctant to speak up. This isn't an Asian thing at all, the Japanese have fully embraced CRM. The Koreans and Russians have not.

* https://code7700.com/case_study_asiana_airlines_214.htm

> The airline industry in some countries may have that culture. In some countries it may not.

Sure, there is variation. One fairly good indication of countries that have a bad incident investigation culture are those that have airlines banned from flying in the EU.

I'd like to point out a difference in your example though. South Korea did have some problems with crew resource management, because of the culture of seniority. A lot of effort has been spent on solving that problem. However, that is a separate issue to the idea that incidents are brushed under the carpet. That's a different culture problem. Both are bad.

Notably the article says "The DGCA is investigating the matter and said that it would take the strictest action against those responsible for the incident."

This sounds like regular Indian culture and the statement may be there just for the ears of the general public. But applied to aviation, "taking the strictest action against those responsible" is basically the opposite of Just Culture (https://en.wikipedia.org/wiki/Just_culture).

Disagree. As per your link, "in a system of just culture, discipline is linked to inappropriate behavior, rather than harm". Failing to disclose such an incident would lead to disciplinary action in most countries, including the US I suspect.

Note that the statement seems to be referring to disciplinary action to those responsible for the incident itself, rather than anything to do with failure to disclose.

Yeah as far as I’m aware there is no public reporting of conflicts. (Loss of separation minima, also called a “deal” in ATC speak)

It’s feasible to build this using ADS-B data.

Incidents like this happen all the time, the latest that comes to mind was in Paris CDG [0].


This happened last week.

> A collision between two India-bound Emirates planes was averted at Dubai airport on Sunday. Reports said that the Hyderabad-bound plane was accelerating for take-off from runway 30R when the crew saw another aircraft coming in the same direction at high speed. Take-off was immediately instructed to be aborted by the ATC. The aircraft slowed down safely and cleared the runway via taxiway N4.


Being that was 2 years ago, we may have different definitions for all the time.

Fatal airline crashes are forever popular as news stories, yet are now essentially non-existent in the US, and very rare worldwide, despite the ever expanding number of passenger-miles flown per year. The news industry's solution, I guess, is to serve up reports of near misses.

Not sure why you'd expect crashes to remain rare if journalist stop reporting on situations where things almost went wrong.

I wouldn't.

The airline industry is getting unravaled bit by bit. First it was the Boeing with the MCAS(May Crash Any Second) and now this.

What a deceptive headline! It puts the most horrifying sounding facts first, and negates it all at the end of the sentence, using the most obscure negation they could think of: “averted”.

I have a headline:

“Murder of millions of people alone in their homes obviated by police”

Millions? Over what timeline? Or are we assuming that society collapses without police?

It’s just a made-up headline following the same pattern, for illustration purposes. Don’t take it literally.

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