Is this interpretation right? There are parallel runways, and the plane departing on the runway on the right turned left, into the path of the plane departing parallel on the left?
Yes that's what happened. And this is a very common mistake.
A bit simplified, but what happens is that each flight is assigned a departure procedure during startup. That procedure is runway specific and designed to keep traffic clear of other runways so they can have traffic departing from multiple runways at the same time.
Imagine a runway on the left and one on the right, the left runway departure procedures would have an early left turn and the right runway departure procedures would be straight ahead until some altitude and then a right turn.
Now if you depart from the right runway but accidentally select the departure procedure for the left runway, the instruments (and autopilot) would indicate a left turn at about 500ft, right into the path of traffic from the left runway.
This mistake is common when for example a plane is first assigned the left runway and then during taxi changes to the right runway. Or the preflight paperwork includes the left runway departure procedure, but the actual assignment from ATC is the right runway (this was a source of incidents in Amsterdam for a while with some airlines)
This is exactly why the takeoff clearances say “RNAV xxx, cleared for takeoff”. It’s a last confirmation, right before takeoff, of which departure procedure to use.
Yes exactly. They were within 1000 yards of each other and less than 5 seconds from colliding according to some videos analyzing the GPS data. If you listen to the ATC chat, the American Airlines pilot noticed the other plane going the wrong way himself and made a proactive change to avoid collision without waiting for ATC. Although the traffic controllers did notice and quickly gave out new directions, it may have been too late if the pilot didn’t act.
Edit: They were handed off to departures before tower’s traffic warning. The near-collision occurred in the middle of tower-departures handoff. Tower was warning them of traffic in hopes they were still on the frequency but they probably weren’t, and they noticed traffic just before they contacted departures.
On ATC side, maybe departures could have been more proactive and warn AA of traffic together with tower. On AA side, maybe they could have been listening to tower for a while as they are tuning in to departures (there were 10–20 seconds where AA was not listening to tower anymore and did not come in on departures yet). Seems hard to blame either of them in particular.
Original comment as is:
If the video is to be believed, the tower did tell American right away (at 1:36 in the video, way before any visible corrections by either plane were made) that there is traffic and to stop the climb. It’s unclear whether American paid attention to tower, because seconds later they came in on another frequency saying they have traffic in sight. When asked afterwards whether tower gave them a heads-up they denied it.
Of course, ITA paid even less attention, considering how they were the original cause of this all and how for 30 seconds they ignored ATC’s request to turn right immediately (issued at about the same time that AA was warned about traffic).
This doesn’t contradict that what AA did was proactive and possibly life-saving, but I have a suspicion that the initial deviation by ITA could have been benign if both crews paid their full attention to comms: what if ITA started to turn 270 immediately as they are told to (while continuing to climb up from 1500), and American simply stopped their climb at 1500? I am not 100% confident.
That said, I would also agree ATC could have been more proactive, harder on ITA (instead of just telling them to turn again 30 seconds later). Presumably they are strapped for resources right now.
(There could be errors in the above in case the chart and different radio communication tracks in the video are out of sync with each other, which is possible.)
If “in response” means replying back to tower on tower’s frequency, then no. After the lady on tower frequency told them about traffic (twice), they came in on departures frequency (it was a fresh contact, they started with “good afternoon, American 4 with you”) and said they have traffic in sight.
Edited after I rewatched the video:
1. Tower handed them off to departures.
2. They said bye and stopped listening to tower.
3. ITA veered left.
4. Tower noticed it and warned them, hoping they are still listening.
5. They were evidently not listening to tower anymore, and did not contact departures yet, when they noticed traffic themselves.
6. They greeted departures saying they see traffic, and veered left.
Later at 2:45 American said tower didn’t give them a heads-up. The fact that departures asked them about it could mean that departures thought they were still listening to tower.
Pretty sure the pilots have a second radio and could be listening to both departures and tower during handoff, but it’s unclear whether that’s routine. If they did it, they would have heard tower’s original warning.
> I believe their avoidance maneuver was a climb change.
According to the chart in the video, AA veered to the left. This maneuver started around 1:51 in the video, which is at least 10 seconds after tower warned them of traffic and instructed to stop the climb for the first time around 1:38.
I don’t know if they stopped the climb around 1:38. If we know for sure that they stopped the climb around 1:38 when tower told them so, then there is a good chance they were indeed still listening to tower and heard the traffic warning. If that’s the case, maybe they thought that stopping the climb 10 seconds earlier was insufficient (and tower was wrong about it).
Note that VASAviation's visualisations are not always 100% synched with ATC radio recordings, and the radio usually has gaps removed. It's a useful overview to see the tracks, but take the video's timing with a grain of salt.
Unless it is out of sync by tens of seconds, however, it is clear that they were handed off to departures and were neither responding nor even listening to tower.
One theory in the comments was that ITA loaded the wrong departure in their computer and just flew it without noticing that they were on the wrong side of the airport and/or ATC's prior instructions contradicted the electronic plan.
ITY621 does a readback: "...climb DLREY," meaning they confirmed the departure path for 24L extends forward before heading left; which is different for 25R, which heads left shortly after takeoff: "...RNAV DOCKR."
Is this significantly different from the near mid-air collisions that happen on a regular basis?
The audio does an excellent job of showing a layperson how difficult it is to interpret and who's going wear based on sound, and then I had to go back through the video to see the turn.
These people aren't being paid to do this right now? Is that right? I'm not American, but that's what I've heard.
Because they will be back-paid when the government reopens and if they stop showing up then they will be fired. Now, you could ask: won't they be able to get a job back later, who knows.
I guess the people in this instance realise they're an essential service for the economy and that without them, a lot of people could actually die. So they probably see their role as being more than simply working for the people of low integrity.
In which case it’s their duty to end it. But I don’t see a million people marching in Washington, I don’t see food deliveries failing to reach the White House. I don’t see airports simply close down.
Yeah. It's a super stressful job that doesn't pay well normally and now these people are having to drive Uber on the side to pay their mortgages and put food on the table. I'm definitely not flying until this is sorted out.
Yes, TCAS II warns all the way down to 100m AGL (around 320ft above the ground), and they were already between 1000ft and 1500ft (~400m).
It may or may not have advised what to do (to climb/descent/etc.) because that is turned off below 1000ft, and they were approximately at that altitude at the time.
No, TCAS alerts are inhibited at low altitude. It goes in steps by altitude (above ground) from no alerts at all, to only traffic warning but no resolutions, to resolution but no descends, to normal full operation.
I was watching KBOS https://www.flightaware.com/live/airport/KBOS on Thursday morning and saw a couple of Cape Air flights that looked like they were within 500 feet of each other. I suspect we'll be hearing more of these stories soon.
Kind of blows my mind how primitive this whole system still is. Audio quality is really bad. They're sending instructions by voice. The way they know who is speaking is by just saying their callsign with every message.
I want you to very carefully consider the better options.
Perhaps they type instructions? And hope someone reads them?
Perhaps they drag and drop vectors? Then what, a radial menu with emergency modal screens?
Or maybe they click some buttons, forcing the occasional look away from the screen?
Maybe AI could do it all?
For this, voice is perfect. We have been following instructions by voice since humans could grunt. We do not require anyone to look away from the screen (ATC) or look down from the window outside (pilot) for any reason.
We do not require rebroadcast because everyone can hear and take initiative if required.
By what interface, specifically, should someone required to fly an airplane interact with ATC while flying that airplane? By what interface should someone who needs to see where everyone is all the time be able to contact that pilot that cannot look away from the world outside ever and cannot use their hands for anything but flying at a critical time?
As a commercial pilot, your response is a little glib and kind of ignores the meaningful advances that have been made with D-ATIS, ADS-B In, CPDLC, DUATS, XM weather, etc. Voice is absolutely not perfect, analog FM audio often comes through garbled, pilots have to wait their turn on a busy single-user channel for timely information, etc.
This doesn't even begin to touch on the complexities that will come from full integration of drones and eVTOL into the national airspace, which will absolutely swamp a one-speaker-at-a-time analog FM comms system.
Just a nit, but aircraft/airport communications use AM not FM. This is deliberate, because FM's "capture effect" would mask other transmissions that inevitably occur when two parties randomly press PTT at the same time. With AM, you'll hear a tone, which is the difference frequency between the two transmitters, so you'll know that somebody missed something, and it will probably be repeated. If it were FM only, it would be less obvious that some communications were missed.
Yeah I probably over reacted. But the knee jerk reactions I've seen to some perfectly reasonable systems just wear you down.
You raise good points but I would be very surprised to see digital data streams ever replace voice, and drone control is just a completely different problem. But as you say we'll see.
You make a strong case for voice, but that doesn’t necessarily invalidate their argument, they never said voice should be replaced.
Here’s some ideas:
1. A data side channel
2. Use it to send originator for each message, have unique note on other end per sender so they don’t need to check visually, but also show on their display so corrupted or suspicious sender can be verified, in desperate circumstances (rather than the current case of “that cannot be done at all”).
3. Digital audio, allowing actual high quality audio, which we know does improve comprehension, which should not be optional in this context.
4. Take some lessons from modern coms systems on how to handle overlapping coms, plus the extra bandwidth from digital, so overlapping coms is handled gracefully (I realise the realtime nature prevents being too clever, but perhaps blocking all but the first to speak and playing a tone if you’re being blocked), perhaps with some sensible overrides like atc and anyone declaring an emergency getting priority. Currently overlap obliterates both messages and it’s possible for senders to not even know their message was lost. This has contributed to accidents, whilst basic direct radio transmissions cannot avoid this, smart algorithms with some networking could definitely reduce the failure cases to very rare and extreme scenarios
5. Let atc interact with flight planners on aircraft, show the aircraft’s actual locally programmed flight plan to atc, with clear icons if it differs from the filed plan atc has, and perhaps as an emergency only measure, allow atc to submit a flight plan to the aircraft (not replacing the active plan of course, just as a suggestion/support for struggling pilots, “since you have not understood my instructions 3 times, please review the submitted plan on your flight computer, note how it differs from what you programmed”)
6. Aircraft usually know where they are, and which atc they’re meant to be communicating with, have the data channels talk even when the audio channel is not set correctly. If incompetent pilots forget to switch channel, you can force an alarm instead of launching a fighter jet, or just have a button for “connect to correct atc” and a red light when you’re not on the correct one.
That’s just the ideas I’ve come up with just now. 4. Is probably quite hard to get right, and 5 could add load, so should be done carefully.
But hard to believe the current system is technically optimal, or even vaguely close to optimal.
Admittedly, I know the real reason is that having 1 working system for everyone is better than a theoretically great system that is barely implemented and a complicated mess of handoffs between the 2. But with care they can absolutely improve things, but feels like things are moving a few decades slower than they should be.
> I want you to very carefully consider the better options.
How about digital HD audio at least? In parallel with legacy analog audio.
The next step is visual alerts for pilots if the ATC tries to call _them_. You know, like our phones can do for nearly 150 years.
Edit: I'm studying for a private pilot license, and the difficulties in just understanding what the ATC and the other pilots are talking about is really a major stumbling block for me.
> Edit: I'm studying for a private pilot license, and the difficulties in just understanding what the ATC and the other pilots are talking about is really a major stumbling block for me.
FWIW (and this may not be applicable to you, or you may already be doing it) I found that listening to ATC via LiveATC for my home airport during my car commutes really helped me with radio skills.
If you don't commute, I'd still suggest just listening when you're not in a cockpit and don't have to worry about flying.
Listening to specific airports I was familiar with really helped.
I think that the audio we are listening too is from some ground recording station that isn't necessarily near the airport. We aren't listening to a recording of what the pilots heard or what air traffic control hears.
Yup. Audio is sourced from volunteers with home radios & antennas. Quality will be dependant on how far the nearest one was from LAX and their personal setup. Not necessarily representative of quality that the controller/pilot was hearing.
Technically correct...and yet let's not kid ourselves that even with a nice radio and a pair of Bose A30's, it can be hard to tease out exactly what's being said when in a congested airspace.
Right? Just in a car, we know that talking to someone in the car itself has adverse effects on situational awareness, and talking to someone on a phone is much worse than that. But even after all the research and training that goes into human factors in aviation ... we can't do better than confusing, poor quality, AM band party lines during critical phases of flight?
Keep in mind that the person talking and listening to the radio is not the pilot flying the airplane. Pilot and Copilot alternate which job they are doing. It's not the same as the driver of a car talking on a phone.
CPDLC is text messaging between controllers and pilots. It is widely used amongst most carriers. It does not work for time critical situations. Voice and radio is the only solution that will work when you don't have time to type a message.
Talking to someone on the phone who has a birds eye view of the road, other drivers, and the map, and only addresses you to help you drive? in no way possible reduces your situational awareness. I refuse to believe that.
Now idle chatting with coworker Wendy about dinner will take you out of that situation and make you more dangerous.
Is your problem a trust issue with always-updating AWS-hosted randomly-banned silently-breaking framework-rotating modern web apps, or something fundamental with GUI based systems?
I mean, I wouldn’t trust a literal iPad, but I’m not sure if I distrust an entirely figurative iPad.
The problem is fundamentally the fact that it is a visual based system.
It is generally faster to communicate orally and process communication aurally than by text message when the message is short enough and requires immediate attention. This is also why urgent alarms (such as those provided by the Gound Proximity Warning System (GPWS) or Traffic Collision Avoidance System[1] (TCAS) have such a component). Some stall prevention systems are even partially tactile based (making a pretty unmistakable shaking feeling (it is loud as well)).
It is incredibly slow to type and then process that visual information. In addition, it's also just much more reliable.
For time critical situations, it's not a viable option.
[1]: Yes, TCAS has a visual component and many alarms do too, but the RAs are auditory and give specific, to the point, instructions on what to do ("climb", "descend").
Open to suggestions. Keep in mind I've worked on Aircraft control systems and have a very strong opinion on reliability and crew management.
I also note that the budget isn't infinite nor do these aircraft like running electron apps.
Also note that not all (if not most) aircraft are not brand new and so would need all to be retrofitted and re-rerated w/ any new system and every single pilot retrained.
This requirement also includes systems for general aviation pilots and both to be able to sync with each other.
> Also note that not all (if not most) aircraft are not brand new and so would need all to be retrofitted and re-rerated w/ any new system and every single pilot retrained
Ah yes, I forgot, we never introduce new aircraft technology because it's too hard. Too bad we don't, it would be great to fit aircraft, with, say, anti-collision transponders and advanced ground proximity systems. Oh well, my mistake for even bringing it up.
as the video says at the beginning, the audio is sourced from LiveATC, which is a network of volunteers with their own radio equipment [0] who tune in to ATC frequencies and then livestream them.
those volunteers are by necessity not at the airport itself, but some distance away. and the audio is compressed to 16kbps MP3 for livestreaming purposes.
this means the sound quality we're hearing is going to be worse (significantly worse, in some cases) than what the pilots and controllers actually hear.
> They're sending instructions by voice.
I get that it's 2025 and it's tempting to say "everything should be a text message". but remember that there's 2 pilots in the aircraft, the Pilot Flying and the Pilot Monitoring [1].
under normal circumstances, the PM handles talking to ATC (among other duties). but both pilots have headsets that allow them to hear transmissions from ATC. and crucially for the Pilot Flying, they hear those messages without taking their eyes away from actually flying.
modern aircraft do have a text message system of sorts [2] but there is a very good reason why the crucial ATC instruction in this case ("turn right heading 270 immediately") happens via voice and not an ACARS message.
also, it's important to remember that airline pilots in the US have a minimum of 1500 hours of flying time, and pilots flying an A330 on an LAX-Rome route probably have significantly more than that. we're watching a 5-minute video and going "oh it's a bit hard for me to follow this" but for actual commercial pilots this radio chatter is routine and something they have been practicing for years.
It has to do with how ATC needs to be able to communicate with all planes in the air, even ones built 100 years ago. They have to use radio so everyone can hear everyone else. There’s no other technology that is as ubiquitous as radio, so they have to work with what they’ve got. Upgrading to other stuff would be an absolute nightmare, though they are making progress on less critical fronts.
Couldn't comms broadcast in multiple parallel modes, like cell phone traffic?: More clear (probably digital) transmissions in on band, and for backward compatibility, old radio transmissions in another.
I think one of the best things they could add would be an electronic drawing tablet for ATC to draw a flight path on a map and pipe it directly into the pilots EFIS or HUD. It's not fool-proof, but in high density airspace, it seems more efficient to be able to draw a curve and press a button than try to verbally describe it. Of course one major pitfall is you cannot draw in 3D.
They already have something better than that. It's called a published departure procedure that pilots are supposed to follow. In this case, one of the pilots failed to follow the published departure procedure and came close to being on the next season of Mayday: Air Disaster.
Like with all voice communications, context is important. There are only a limited number of things normally said and most transmissions are about things that were decided before the flight. Everyone involved is used to the bandwidth limited audio used here. Non-pilots have none of this context and normally have a hard time understanding these transmissions.
For ATC environments the voice data is a series of pre-expected prompts. You could do something different but you would pretty much have to redesign the whole system from scratch without making things significantly more complex. Complexity is the enemy of reliability.
Other than voice how would you send instructions that don't really on changing your focus? I can listen while doing other things. What else would you do?
One of the YouTube commenters contributed some much-needed nuance. JFK Ground added to the confusion by repeatedly refusing to use standard phraseology, and failed to maintain professionalism, getting audibly angry and impatient. Both sides of the radio conversation had problems.
Primitive but has been working well enough for decades is so much better than the prospect of Accenture coming in with their absolutely incompetent bullshit.
Most Americans have zero agency in the matter. We vote once a year or two, most of our states or districts aren’t competitive, and the candidates we do elect can ignore their constituents easily.
Who are you yelling at? Do you think the Trump administration reads Hacker News? What do you expect the average American taxpayer to do to fix a government shutdown?
This happened on 10/31/25 https://avherald.com/h?article=52f72b6c&opt=0
Is this interpretation right? There are parallel runways, and the plane departing on the runway on the right turned left, into the path of the plane departing parallel on the left?
Yes that's what happened. And this is a very common mistake.
A bit simplified, but what happens is that each flight is assigned a departure procedure during startup. That procedure is runway specific and designed to keep traffic clear of other runways so they can have traffic departing from multiple runways at the same time.
Imagine a runway on the left and one on the right, the left runway departure procedures would have an early left turn and the right runway departure procedures would be straight ahead until some altitude and then a right turn.
Now if you depart from the right runway but accidentally select the departure procedure for the left runway, the instruments (and autopilot) would indicate a left turn at about 500ft, right into the path of traffic from the left runway.
This mistake is common when for example a plane is first assigned the left runway and then during taxi changes to the right runway. Or the preflight paperwork includes the left runway departure procedure, but the actual assignment from ATC is the right runway (this was a source of incidents in Amsterdam for a while with some airlines)
If you're really interested, read this incident report via Google Translate, it describes exactly how this type of incident happens: https://www.lvnl.nl/voorvallen/20220415-verlies-van-afstand-...
This is exactly why the takeoff clearances say “RNAV xxx, cleared for takeoff”. It’s a last confirmation, right before takeoff, of which departure procedure to use.
Yes exactly. They were within 1000 yards of each other and less than 5 seconds from colliding according to some videos analyzing the GPS data. If you listen to the ATC chat, the American Airlines pilot noticed the other plane going the wrong way himself and made a proactive change to avoid collision without waiting for ATC. Although the traffic controllers did notice and quickly gave out new directions, it may have been too late if the pilot didn’t act.
Edit: They were handed off to departures before tower’s traffic warning. The near-collision occurred in the middle of tower-departures handoff. Tower was warning them of traffic in hopes they were still on the frequency but they probably weren’t, and they noticed traffic just before they contacted departures.
On ATC side, maybe departures could have been more proactive and warn AA of traffic together with tower. On AA side, maybe they could have been listening to tower for a while as they are tuning in to departures (there were 10–20 seconds where AA was not listening to tower anymore and did not come in on departures yet). Seems hard to blame either of them in particular.
Original comment as is:
If the video is to be believed, the tower did tell American right away (at 1:36 in the video, way before any visible corrections by either plane were made) that there is traffic and to stop the climb. It’s unclear whether American paid attention to tower, because seconds later they came in on another frequency saying they have traffic in sight. When asked afterwards whether tower gave them a heads-up they denied it.
Of course, ITA paid even less attention, considering how they were the original cause of this all and how for 30 seconds they ignored ATC’s request to turn right immediately (issued at about the same time that AA was warned about traffic).
This doesn’t contradict that what AA did was proactive and possibly life-saving, but I have a suspicion that the initial deviation by ITA could have been benign if both crews paid their full attention to comms: what if ITA started to turn 270 immediately as they are told to (while continuing to climb up from 1500), and American simply stopped their climb at 1500? I am not 100% confident.
That said, I would also agree ATC could have been more proactive, harder on ITA (instead of just telling them to turn again 30 seconds later). Presumably they are strapped for resources right now.
(There could be errors in the above in case the chart and different radio communication tracks in the video are out of sync with each other, which is possible.)
They said they had traffic in sight in response. As in "yes I see them". I believe their avoidance maneuver was a climb change.
If “in response” means replying back to tower on tower’s frequency, then no. After the lady on tower frequency told them about traffic (twice), they came in on departures frequency (it was a fresh contact, they started with “good afternoon, American 4 with you”) and said they have traffic in sight.
Edited after I rewatched the video:
1. Tower handed them off to departures.
2. They said bye and stopped listening to tower.
3. ITA veered left.
4. Tower noticed it and warned them, hoping they are still listening.
5. They were evidently not listening to tower anymore, and did not contact departures yet, when they noticed traffic themselves.
6. They greeted departures saying they see traffic, and veered left.
Later at 2:45 American said tower didn’t give them a heads-up. The fact that departures asked them about it could mean that departures thought they were still listening to tower.
Pretty sure the pilots have a second radio and could be listening to both departures and tower during handoff, but it’s unclear whether that’s routine. If they did it, they would have heard tower’s original warning.
> I believe their avoidance maneuver was a climb change.
According to the chart in the video, AA veered to the left. This maneuver started around 1:51 in the video, which is at least 10 seconds after tower warned them of traffic and instructed to stop the climb for the first time around 1:38.
I don’t know if they stopped the climb around 1:38. If we know for sure that they stopped the climb around 1:38 when tower told them so, then there is a good chance they were indeed still listening to tower and heard the traffic warning. If that’s the case, maybe they thought that stopping the climb 10 seconds earlier was insufficient (and tower was wrong about it).
Note that VASAviation's visualisations are not always 100% synched with ATC radio recordings, and the radio usually has gaps removed. It's a useful overview to see the tracks, but take the video's timing with a grain of salt.
I mentioned that in my original comment.
Unless it is out of sync by tens of seconds, however, it is clear that they were handed off to departures and were neither responding nor even listening to tower.
One theory in the comments was that ITA loaded the wrong departure in their computer and just flew it without noticing that they were on the wrong side of the airport and/or ATC's prior instructions contradicted the electronic plan.
They had the correct SID, but the wrong runway.
ITY621 does a readback: "...climb DLREY," meaning they confirmed the departure path for 24L extends forward before heading left; which is different for 25R, which heads left shortly after takeoff: "...RNAV DOCKR."
Is this significantly different from the near mid-air collisions that happen on a regular basis?
The audio does an excellent job of showing a layperson how difficult it is to interpret and who's going wear based on sound, and then I had to go back through the video to see the turn.
These people aren't being paid to do this right now? Is that right? I'm not American, but that's what I've heard.
I can't speak to the first question, but as to the second, correct, US air traffic controllers are not currently being paid.
[1]: https://www.nytimes.com/2025/11/07/travel/shutdown-air-traff....
[2]: https://www.nytimes.com/2025/10/20/us/politics/shutdown-air-....
[3]: https://www.theguardian.com/us-news/2025/oct/28/air-traffic-...
Why are they turning up for work?
Because they will be back-paid when the government reopens and if they stop showing up then they will be fired. Now, you could ask: won't they be able to get a job back later, who knows.
Actually, the administration has cast doubt on if they will actually provide backpay. It's now anybody's guess.
People of high integrity generally hold these jobs.
Not Googlers threatening a general strike because they took onion bagels off the cafeteria menu.
People of high integrity don’t work without paying wages.
People of high integrity don’t work for people of low integrity.
Maybe you want to rephrase your last sentence because right now it reads as an insult to all federal workers.
If you’re meekly doing your job rather than actually using your power to end this then yes.
I guess the people in this instance realise they're an essential service for the economy and that without them, a lot of people could actually die. So they probably see their role as being more than simply working for the people of low integrity.
In which case it’s their duty to end it. But I don’t see a million people marching in Washington, I don’t see food deliveries failing to reach the White House. I don’t see airports simply close down.
Yeah. It's a super stressful job that doesn't pay well normally and now these people are having to drive Uber on the side to pay their mortgages and put food on the table. I'm definitely not flying until this is sorted out.
And maybe some time to ramp back up to pre-shit-show skill levels.
Question for any aviation expert: Would TCAS be triggered at such a low altitude on departure?
Yes, TCAS II warns all the way down to 100m AGL (around 320ft above the ground), and they were already between 1000ft and 1500ft (~400m).
It may or may not have advised what to do (to climb/descent/etc.) because that is turned off below 1000ft, and they were approximately at that altitude at the time.
No, TCAS alerts are inhibited at low altitude. It goes in steps by altitude (above ground) from no alerts at all, to only traffic warning but no resolutions, to resolution but no descends, to normal full operation.
I was watching KBOS https://www.flightaware.com/live/airport/KBOS on Thursday morning and saw a couple of Cape Air flights that looked like they were within 500 feet of each other. I suspect we'll be hearing more of these stories soon.
If you are casually listening to ATC for fun then you should be able to recognize that the event in this story is not ATC error...
https://youtube.com/watch?v=jgWuw-TCRkI
ITA plane taking off around 1:08:15. The camera doesn't follow it but you might be able to hear someone yelling wtf around 1:08:58.
Kind of blows my mind how primitive this whole system still is. Audio quality is really bad. They're sending instructions by voice. The way they know who is speaking is by just saying their callsign with every message.
There's got to be a better solution surely?
I want you to very carefully consider the better options.
Perhaps they type instructions? And hope someone reads them?
Perhaps they drag and drop vectors? Then what, a radial menu with emergency modal screens?
Or maybe they click some buttons, forcing the occasional look away from the screen?
Maybe AI could do it all?
For this, voice is perfect. We have been following instructions by voice since humans could grunt. We do not require anyone to look away from the screen (ATC) or look down from the window outside (pilot) for any reason.
We do not require rebroadcast because everyone can hear and take initiative if required.
By what interface, specifically, should someone required to fly an airplane interact with ATC while flying that airplane? By what interface should someone who needs to see where everyone is all the time be able to contact that pilot that cannot look away from the world outside ever and cannot use their hands for anything but flying at a critical time?
Chesterton's ATC.
As a commercial pilot, your response is a little glib and kind of ignores the meaningful advances that have been made with D-ATIS, ADS-B In, CPDLC, DUATS, XM weather, etc. Voice is absolutely not perfect, analog FM audio often comes through garbled, pilots have to wait their turn on a busy single-user channel for timely information, etc.
This doesn't even begin to touch on the complexities that will come from full integration of drones and eVTOL into the national airspace, which will absolutely swamp a one-speaker-at-a-time analog FM comms system.
Just a nit, but aircraft/airport communications use AM not FM. This is deliberate, because FM's "capture effect" would mask other transmissions that inevitably occur when two parties randomly press PTT at the same time. With AM, you'll hear a tone, which is the difference frequency between the two transmitters, so you'll know that somebody missed something, and it will probably be repeated. If it were FM only, it would be less obvious that some communications were missed.
https://en.wikipedia.org/wiki/Capture_effect
Yeah I probably over reacted. But the knee jerk reactions I've seen to some perfectly reasonable systems just wear you down.
You raise good points but I would be very surprised to see digital data streams ever replace voice, and drone control is just a completely different problem. But as you say we'll see.
You make a strong case for voice, but that doesn’t necessarily invalidate their argument, they never said voice should be replaced.
Here’s some ideas: 1. A data side channel 2. Use it to send originator for each message, have unique note on other end per sender so they don’t need to check visually, but also show on their display so corrupted or suspicious sender can be verified, in desperate circumstances (rather than the current case of “that cannot be done at all”). 3. Digital audio, allowing actual high quality audio, which we know does improve comprehension, which should not be optional in this context. 4. Take some lessons from modern coms systems on how to handle overlapping coms, plus the extra bandwidth from digital, so overlapping coms is handled gracefully (I realise the realtime nature prevents being too clever, but perhaps blocking all but the first to speak and playing a tone if you’re being blocked), perhaps with some sensible overrides like atc and anyone declaring an emergency getting priority. Currently overlap obliterates both messages and it’s possible for senders to not even know their message was lost. This has contributed to accidents, whilst basic direct radio transmissions cannot avoid this, smart algorithms with some networking could definitely reduce the failure cases to very rare and extreme scenarios 5. Let atc interact with flight planners on aircraft, show the aircraft’s actual locally programmed flight plan to atc, with clear icons if it differs from the filed plan atc has, and perhaps as an emergency only measure, allow atc to submit a flight plan to the aircraft (not replacing the active plan of course, just as a suggestion/support for struggling pilots, “since you have not understood my instructions 3 times, please review the submitted plan on your flight computer, note how it differs from what you programmed”) 6. Aircraft usually know where they are, and which atc they’re meant to be communicating with, have the data channels talk even when the audio channel is not set correctly. If incompetent pilots forget to switch channel, you can force an alarm instead of launching a fighter jet, or just have a button for “connect to correct atc” and a red light when you’re not on the correct one.
That’s just the ideas I’ve come up with just now. 4. Is probably quite hard to get right, and 5 could add load, so should be done carefully. But hard to believe the current system is technically optimal, or even vaguely close to optimal.
Admittedly, I know the real reason is that having 1 working system for everyone is better than a theoretically great system that is barely implemented and a complicated mess of handoffs between the 2. But with care they can absolutely improve things, but feels like things are moving a few decades slower than they should be.
> I want you to very carefully consider the better options.
How about digital HD audio at least? In parallel with legacy analog audio.
The next step is visual alerts for pilots if the ATC tries to call _them_. You know, like our phones can do for nearly 150 years.
Edit: I'm studying for a private pilot license, and the difficulties in just understanding what the ATC and the other pilots are talking about is really a major stumbling block for me.
> Edit: I'm studying for a private pilot license, and the difficulties in just understanding what the ATC and the other pilots are talking about is really a major stumbling block for me.
FWIW (and this may not be applicable to you, or you may already be doing it) I found that listening to ATC via LiveATC for my home airport during my car commutes really helped me with radio skills.
If you don't commute, I'd still suggest just listening when you're not in a cockpit and don't have to worry about flying.
Listening to specific airports I was familiar with really helped.
I think that the audio we are listening too is from some ground recording station that isn't necessarily near the airport. We aren't listening to a recording of what the pilots heard or what air traffic control hears.
Yup. Audio is sourced from volunteers with home radios & antennas. Quality will be dependant on how far the nearest one was from LAX and their personal setup. Not necessarily representative of quality that the controller/pilot was hearing.
Technically correct...and yet let's not kid ourselves that even with a nice radio and a pair of Bose A30's, it can be hard to tease out exactly what's being said when in a congested airspace.
https://www.liveatc.net/
If you want to listen in yourself.
This is one of the highest quality recordings of such traffic that I have heard. They are usually a lot worse.
Right? Just in a car, we know that talking to someone in the car itself has adverse effects on situational awareness, and talking to someone on a phone is much worse than that. But even after all the research and training that goes into human factors in aviation ... we can't do better than confusing, poor quality, AM band party lines during critical phases of flight?
Keep in mind that the person talking and listening to the radio is not the pilot flying the airplane. Pilot and Copilot alternate which job they are doing. It's not the same as the driver of a car talking on a phone.
CPDLC is text messaging between controllers and pilots. It is widely used amongst most carriers. It does not work for time critical situations. Voice and radio is the only solution that will work when you don't have time to type a message.
Talking to someone on the phone who has a birds eye view of the road, other drivers, and the map, and only addresses you to help you drive? in no way possible reduces your situational awareness. I refuse to believe that.
Now idle chatting with coworker Wendy about dinner will take you out of that situation and make you more dangerous.
Would you rather them read text messages on their iPads?
Is your problem a trust issue with always-updating AWS-hosted randomly-banned silently-breaking framework-rotating modern web apps, or something fundamental with GUI based systems?
I mean, I wouldn’t trust a literal iPad, but I’m not sure if I distrust an entirely figurative iPad.
The problem is fundamentally the fact that it is a visual based system.
It is generally faster to communicate orally and process communication aurally than by text message when the message is short enough and requires immediate attention. This is also why urgent alarms (such as those provided by the Gound Proximity Warning System (GPWS) or Traffic Collision Avoidance System[1] (TCAS) have such a component). Some stall prevention systems are even partially tactile based (making a pretty unmistakable shaking feeling (it is loud as well)).
It is incredibly slow to type and then process that visual information. In addition, it's also just much more reliable.
For time critical situations, it's not a viable option.
[1]: Yes, TCAS has a visual component and many alarms do too, but the RAs are auditory and give specific, to the point, instructions on what to do ("climb", "descend").
Oh of course, those are the only two options: either an AM band party line or text messages on an iPad. Nothing else is possible.
Open to suggestions. Keep in mind I've worked on Aircraft control systems and have a very strong opinion on reliability and crew management.
I also note that the budget isn't infinite nor do these aircraft like running electron apps.
Also note that not all (if not most) aircraft are not brand new and so would need all to be retrofitted and re-rerated w/ any new system and every single pilot retrained.
This requirement also includes systems for general aviation pilots and both to be able to sync with each other.
> Also note that not all (if not most) aircraft are not brand new and so would need all to be retrofitted and re-rerated w/ any new system and every single pilot retrained
Ah yes, I forgot, we never introduce new aircraft technology because it's too hard. Too bad we don't, it would be great to fit aircraft, with, say, anti-collision transponders and advanced ground proximity systems. Oh well, my mistake for even bringing it up.
Suggest a specific idea, instead of this theatrical sarcasm.
> Audio quality is really bad.
as the video says at the beginning, the audio is sourced from LiveATC, which is a network of volunteers with their own radio equipment [0] who tune in to ATC frequencies and then livestream them.
those volunteers are by necessity not at the airport itself, but some distance away. and the audio is compressed to 16kbps MP3 for livestreaming purposes.
this means the sound quality we're hearing is going to be worse (significantly worse, in some cases) than what the pilots and controllers actually hear.
> They're sending instructions by voice.
I get that it's 2025 and it's tempting to say "everything should be a text message". but remember that there's 2 pilots in the aircraft, the Pilot Flying and the Pilot Monitoring [1].
under normal circumstances, the PM handles talking to ATC (among other duties). but both pilots have headsets that allow them to hear transmissions from ATC. and crucially for the Pilot Flying, they hear those messages without taking their eyes away from actually flying.
modern aircraft do have a text message system of sorts [2] but there is a very good reason why the crucial ATC instruction in this case ("turn right heading 270 immediately") happens via voice and not an ACARS message.
also, it's important to remember that airline pilots in the US have a minimum of 1500 hours of flying time, and pilots flying an A330 on an LAX-Rome route probably have significantly more than that. we're watching a 5-minute video and going "oh it's a bit hard for me to follow this" but for actual commercial pilots this radio chatter is routine and something they have been practicing for years.
0: https://www.liveatc.net/faq/
1: https://skybrary.aero/articles/pilot-flying-pf-and-pilot-mon...
2: https://en.wikipedia.org/wiki/ACARS
For starters, ADS-B is being rolled out, allows planes to 'see' each other and respond in real time.
https://en.wikipedia.org/wiki/Automatic_Dependent_Surveillan...
It’s been required in the US since 2020. But, ADS-B would not have played a factor in this incident.
It has to do with how ATC needs to be able to communicate with all planes in the air, even ones built 100 years ago. They have to use radio so everyone can hear everyone else. There’s no other technology that is as ubiquitous as radio, so they have to work with what they’ve got. Upgrading to other stuff would be an absolute nightmare, though they are making progress on less critical fronts.
Couldn't comms broadcast in multiple parallel modes, like cell phone traffic?: More clear (probably digital) transmissions in on band, and for backward compatibility, old radio transmissions in another.
I think one of the best things they could add would be an electronic drawing tablet for ATC to draw a flight path on a map and pipe it directly into the pilots EFIS or HUD. It's not fool-proof, but in high density airspace, it seems more efficient to be able to draw a curve and press a button than try to verbally describe it. Of course one major pitfall is you cannot draw in 3D.
That would be slower and ironically less precise than what we already have, which is navigation by named waypoints.
They already have something better than that. It's called a published departure procedure that pilots are supposed to follow. In this case, one of the pilots failed to follow the published departure procedure and came close to being on the next season of Mayday: Air Disaster.
Like with all voice communications, context is important. There are only a limited number of things normally said and most transmissions are about things that were decided before the flight. Everyone involved is used to the bandwidth limited audio used here. Non-pilots have none of this context and normally have a hard time understanding these transmissions.
For ATC environments the voice data is a series of pre-expected prompts. You could do something different but you would pretty much have to redesign the whole system from scratch without making things significantly more complex. Complexity is the enemy of reliability.
What do you propose that is better? VC-backed smartphone apps?
Aircraft have much better quality electronics than a $20 tabletop radio located some distance away by whoever is ripping the stream.
Other than voice how would you send instructions that don't really on changing your focus? I can listen while doing other things. What else would you do?
What's the most reliable situation you can think of that will never fail and drive better audio quality?
This is a field where they need more .9999s than Amazon.
Amazon is up to, what, one and half nines right now?
Amazon is still at 5 9's availability, they just shifted the decimal point left once.
5 9s in 95.79999%
Unintelligible audio is a failure mode.
Seems to work pretty well most of the time w/ souls involved. Works better than most websites on hard lines.
The canonical counter-example against voice/audio:
https://www.youtube.com/watch?v=1NDqZy4deDI
JFK controller tries to communicate with Air China 981
One of the YouTube commenters contributed some much-needed nuance. JFK Ground added to the confusion by repeatedly refusing to use standard phraseology, and failed to maintain professionalism, getting audibly angry and impatient. Both sides of the radio conversation had problems.
Exactly, voice comms has a large number of disadvantages. Thanks for expanding on the point I was making.
You mean a situation where a pilot who is supposed to know English in the parlance of global aviation lingo seems to be playing dumb?
That is a unique thought.
I'm assuming you don't listen to ATC traffic much, and have general HN assumption you just know better than everyone else.
Maybe assume less.
Primitive but has been working well enough for decades is so much better than the prospect of Accenture coming in with their absolutely incompetent bullshit.
safest mode of transportation strikes again
Government shutdown. ATC are not being paid.
Sort your country out!
Most Americans have zero agency in the matter. We vote once a year or two, most of our states or districts aren’t competitive, and the candidates we do elect can ignore their constituents easily.
Who are you yelling at? Do you think the Trump administration reads Hacker News? What do you expect the average American taxpayer to do to fix a government shutdown?
"trollied"... perhaps the clue is in the name?
General strike. Certainly government employees should be on strike. Starting with secret service.