For those interested in the various aircraft systems for PA (public address) and aircraft status system for aircrew, I found this interesting training doc PDF online [1] for the A320/321.
I have been looking at section "03-010 CABIN INTERCOMMUNICATION DATA SYSTEM"
It does not mention the "medical intercom jacks" in overhead bins that are mentioned at the end of the article
Another idea is that there is a source file that is copied onto the flash card on a regular basis and someone has hacked the source back at the office or something. Seems more likely because that wouldn't require the perpetrator to be on each flight and thus less likely to get caught. Some of these flights play music as you board the plane, could it be that this comes from music on a flash card and someone has replaced that?
They would probably notice that but it does seem like some former passenger most likely installed something that's patched into the system. It may just be a recording from a flash drive. Or it could also be more sophisticated and patch into the wifi as well. You could also imagine it having a microphone for added hijinx but none of the interactions seem to suggest that.
I've flown American six times in the last ten days, and four of the flights had chaos with the entertainment system. No groans or heavy breathing on the PA, but flight attendants had to "reboot the system" once or twice every flight.
I once captured the Linux boot screen of a United Boeing 737 infotainment system. Apparently I still got that photo. OCRed text for lols:
video capture buffer0 40b37460
video capture buffer1 40a8dd60
wideo_capture buffer2 409e4610
geode_: gamma black+csccorrection
VAL2: Registered "NSC Geode V4LZ UBI driver" as char device B1, 224
VAL2: Registered "NSC Geode V4L2 Capture driver" as char device 81,
geode_v: Unknown standard
VAL2: Registered "NSC Geode V4LZ Overlay driver" as char device B1, 16
Warning: loading /lib/modules/realmagichul_kernelland.o will taint the kernel: non-GPL license - Proprietary. Copyright (c) 2002 Sigma Designs Inc. All rights reserved (version 103 with proc pci dolby css macrovision sm2288 osdric_memorycheck),
/lib/modules/realmagichul_kernelland.o:init_module:Invalidargument
Hint: insmod errors Can be caused by incorrect module parameters, including invalid IO or IRQ parameters
PCI: Setting latency timer of device 00:12.3 to 32
geodeoss: disabling PM: PM registration failed
geodeoss: version 1.2.0 time 12:37:36 Dec B 2004
geodeoss: use_pm=0 check_interrupt=0
Warning: loading /lib/modules/maspcu.o will taint the kernel: no license
usb.c: registered new driver pcu
MAS-eFX SEB USB PCU driver version 1.01
usb.c: registered new driver usbccr
usb_ccr open is being called (0xc165f000
) <6›ccrdev.c: Adding credit card reader: input1
input1: Panasonic Avionics Corp PAC USB Keyboard/Credit Card Reader Ver. 1.01 on usb1:2.1
usbccr.c: v0.59:USB HID Credit Card Reader driver
mice: PS/2 mouse device common for all mice
usb.c: registered new driver pacpcu
geode rev-7 pmr-03a834c4 mcr-00030250
using /dev/mtd1 /usr/app
--- mount succeeded ---
using /dev/mtd4 /usr/app2
--- mount succeeded ---
> I once captured the Linux boot screen of a United Boeing 737 infotainment system.
I used to work adjacent to these exact systems...they're so bad.
Like, 10+ minute boot at times, or assigning multiple devices to the same IP, or the communication network just randomly dying... (and this was all in vitro testing)
It was still cool to see "the rack", aka an entire planes infotainment system setup on a rolling cart including however many seat backs each plane was supposed to have. They had multiple office buildings that were essentially full of these, because each airline and deployment was different enough that they didn't want to have to reconfigure when needing to test them.
Some of the time is because they have a single board computer, and only licensing the BIOS. You'll know if that's the case if after the boot, you see it purposely set the time to something arbitrary, but dating back to the 90's. To the flight entertainment, the date doesn't really matter. For the licensing however, it does.
Also elsewhere in the boot, you might notice they tend to be 80486 CPU emulation boards from Cyrix. They're not fast at all, but for what they do, they don't need to be.
Also, if you took video instead of a pic, there are a few interesting IP addresses might scroll by as the media program gets initialized.
They might be doing that out of caution just to keep it from being exploited. Sounds like something management or the Flight Crew might decide is a band aid if one tries it and it works then everybody starts doing it. Knee jerk reaction but sounds like they’re stumped.
If you watch the whole boot, they purposely set the date to the 90's. I think it is because they don't want to pay the license for the BIOS. You can see some text about that license scroll by as well.
I've seen it often, and somewhere on an old PeeCee buried in the darkest areas of my home office, I have a video of the whole sequence.
I recently had some funny business on a United Airlines flight where the high-low chime (you hear for the seatbelt sign and landing gear, etc.) was going bonkers and chimed maybe 10 times in a row while the cabin lights faded on and off.
No announcements were made by the pilot or flight attendants afterwards, and everyone was left confused. I turned to the passenger next to me and we both shrugged.
If it were just one passenger it would be easy to find out who she is by cross checking passenger lists. So probably not. Maybe a coordinated 4chan-style prank.
What's interesting is that it appears that the CF card slot is only accessible behind a panel. The only people that would have access to that are likely the ground crew -- possibly doing a software update, or other maintenance on that panel.
If there is such a flash card, this sounds like the easiest explanation. Someone swapped the card with a file that starts with the real announcement, then X minutes of silence, followed by joke sounds.
Absolutely did this in middle school music class, where there was a cassette player that usually went unused. I don’t remember the details but it was basically 10 minutes of silence and then some raunchy audio, probably NIN or Marilyn Manson (it was 1998 and we were 12).
Especially if the crew is used to the player stopping automatically at the end of the spiel. The attendants wouldn't suspect the player because the earlier announcement ended so why would playback still be going?
Looked at that too, but since unless I am missing something, that appears to be in the captain’s cabin based on linked document from the parent of this comment thread; which means it would not only be hard to access, but once placed, very likely be hard to recover and would have been checked too, likely even in flight while the audio continued to be heard.
If those are 1/4" or 6.35mm audio phone jacks, I'm sure there are lots of electrical engineers who could design a pre-recorded player that would fit
ENTIRELY inside the jack without protruding outside the jack whatsoever.
An ESP32-PICO-D4 is 7mm wide, but based on internal images it appears you can safely grind it down to ~6.35mm. It contains a DAC, 4MB flash, and all needed peripherals plus bluetooth. The quality [1] would be poor, but this matches what we observed.
A circuit board would probably be out of the question given the size. Even 0.8mm would have very little usable area. Flex PCB could work well, but is probably overkill for the complexity required. I'd expect a project like this to be hand soldered, given the low (less than 6?) component count. It wouldn't be easy, but well within the capabilities of a hobbyist at home with a cheap USB microscope.
For power, I could imagine a repurposed AirPod battery (they fit in the 0.235 inch diameter "stem" of the headphone) with a deadbugged switching or linear regulator fitting both the power budget and the size constraint.
From a physical design perspective, a lot of traditional methods seem impractical. With this size constraint one possibility could be placing requisite components into a 1/4" jack shaped mold, and casting it in epoxy in a vacuum, completing the conductive surfaces with copper tape.
I'm struggling to understand how this would explain the account here:
>Then the master power button up at 1L for the cabin power kept getting I pushed so it would shut off all the IFE, seat power and outlets. I had to push the button on again about 3 times inflight. Then the 2 got a call with the same groaning noise and thought it was one of us playing a joke but it wasn't us.
>It certainly was freaking all of us and the passengers. They wanted off the plane as bad as we did. The 2 be FAs said they had been on the plane the other day and the same thing happened. I had a visual on each FA when the noise would come over the PA and one time when the FO was doing a break so unless the captain was playing a long sick, joke I don't have an explanation.
Uninformed guess: "The master [public address system] power button [located] up by [seat] 1L kept getting pushed so it would shut off all the IFE [(inflight entertainment)]"
This makes sense, because for safety reasons all the entertainment is paused when they use the public address system.
I think "master power button" probably more clearly means some sort of master control switch for in-seat passenger accessory power, since it's described as shutting off all in-flight entertainment AND seat power. The sort of thing you're supposed to press during takeoff and landing, not during announcements
You're right, I forgot because I have just used my phone the last few years. Now I remember I always found it incredibly annoying because I'd miss part of the dialogue of what I was watching.
While it is plausible that the hack compromises the entire comm system, it's unlikely. My bet is that the steward made an incorrect association between the sounds and normal system behavior. These inaccurate retellings are extremely common in ghost stories.
Only time will tell, but I'm almost certain I'm right on this one.
This makes a lot of sense, but I’ll add that it’s also possible that the association was correct, but not for the assumed reason. For example, maybe the plane had a partially faulty breaker for the IFE, and there was a likelihood of tripping every time the PA system was used. (The button probably isn’t a breaker, but there’s a world of similar explanations.)
My best guess its an unfunny "Easter Egg" that triggers after something like 5,000 hours of uptime. I think I remember some bug in Boeing or some other system that they need to actually be rebooted every 100 days.
I'm one of those people who thinks easter eggs are great, and miss the days when you had a decent chance of coming across one in a program or game.
The FAA does not agree with that. The FAA probably thinks that easter eggs in avionics software are a crime. And I agree with that position! Aviation, medical, military, and any other critical software should not contain easter eggs, and it should be an offense to knowingly include one. Stuff like this (even though it's probably not an easter egg) is a great example why. Just imagine the cost to patch this if it's widespread... and it has to be patched, because this one can literally kill people if you don't fix it (think spooked flight crews making rushed or generally poor decisions if you don't think this is potentially lethal).
According to the researcher who found it, "they didn’t think it was very funny.”
I love easter eggs myself—classic Apple software in particular had a lot of these, and I really miss finding them—but they're admittedly a risk. I remember one obscure Easter egg in Mac OS 7.6 that occasionally caused crashes at boot time after displaying a bizarre message about how "bluets and granola bars / make a chewy snack". Cute, but probably not something Apple wants to be getting customer support requests about.
As far as the topic at hand, I don't believe these weird noises are an Easter egg, either. I'd guess it's a recording patched in somehow by someone who works for the airline.
Personally I draw the line somewhere around "software that's controlling something". If software can directly screw up or cause damage in the Real World™, that's a good reason it shouldn't have easter eggs in it. If the trouble has to indirect through one or more meatbags who know better before becoming reified, well, the harm caused by any easter eggs is probably much less than the harm caused by reported bugs already closed WONTFIX with a laugh. (Note: PAX do not in fact know better, ever, as any airline employee can and will tell you.)
I looked up the story behind the "Bluets and Granola Bars" easter egg. Apparently, the System Error Handler, part of the boot ROM, used to display a popup that said "Welcome to Macintosh" at startup, before the operating system loaded. However, in System 7.6, this was replaced by a new splash screen with the Mac OS logo, and the old "Welcome to Macintosh" message in the system resource file was replaced with the Granola message (probably under the assumption that it would never be shown). However, if the operating system fails to suppress the boot ROM's popup for whatever reason, the Granola message shows through.
I read in Slash’s autobiography that when he got his pacemaker installed they set it at a certain heart rate, but when he played his first live show, he felt a handful of thumps in his chest and thought it was bigger pyro than normal.
Turns out his pacemaker was shocking him because it thought his elevated heart rate was a danger! They fixed the setting.
Why do you think is it a bad idea to have a defibrillator that flashes PSYCH on screen when the Shock button is pressed, but then delivers an actual shock a second or two later? It would happen only on the fifth cycle of CPR or so!
These sounds are familiar to me from using “ pink trombone”, or praat, both vocal synthesizer. I would guess that a text - to - speech system is bugging out.
https://dood.al/pinktrombone/
The sounds probably aren't a prank or a recording of a human at all. I am guessing it is just a resonant frequency of a standard part being picked up as a feedback loop due to some component which was recently exposed after a change in maintenance protocols. (or something similarly mundane) I have heard all sorts of ghoulish sounds picked up while tinkering with RF and old microchips. Our brains tend to anthropomorphize such sounds when we have never experienced them before. Going straight to the wildest explanations like "hacking" or "ghosts" is fun for our brains but further reinforces the inaccurate picture we had painted for ourselves initially.
I listened to the recording in the article, and it sounds like a human. Further, it sounds like the same human. And I found myself reading the emotional message behind the sounds. So...yeah, it's an interesting theory, but I think it's more likely a prank or someone making a point.
There's a point in the MP3 that sounds possibly non-human at 0:18 to 0:19. The pitch goes quite high in a way that sounds artificial.
But overall I agree that it sounds very human. For example, the grunt at 0:13 doesn't sound like random noise at all, it could easily be a sound effect in a movie or game.
Another way to think about it: there are a lot of planes and different ways the PA system could go wrong. You’re much less likely to read an article about a plane being ‘haunted’ by a strange clicking or buzzing or humming or white noise sound.
I think you’re trying to decide if it’s a prank or not. And (I assume) you care about trying to come to conclusions that are likely correct. Therefore I think you should care about things that would lead you to incorrect conclusions.
Suppose the two possibilities are ‘prank made from human’s voice’ and ‘weird electromechanical phenomenon’. The logic I believe you’ve implicitly applied is that most electromechanical phenomena do not sound human and therefore this human-like sound is likely human. However I put it to you that this logic is flawed because you have not heard a randomly sampled electromechanical phenomenon but rather a sound that was sufficiently human-like to warrant an article about hauntings so thinking about the ordinary distribution of electromechanical phenomena is misleading.
Furthermore I think that you’re assigning relativity equal weight to the two possibilities of a human prankster and any kind of PA system fault when I would argue that the latter is much more common. That is, I think you’re answering a question like ‘we flipped a coin and if it came up heads, we made silly noises into a dictaphone and if it came up tails we tortured the device in some way while it was recording. We’ll play the sound and you can guess which it was’ whereas I think the answer in this case hinges a lot more on the equivalent of the coin-flipping process (eg what if you needed 10 heads in a row for the first choice? What about 15? 20?)
One can formalise this too. I’ve tried to come up with some priors that illustrate the point and which I think are reasonably generous towards your conclusion.
Say H = some human pranking a flight with silly noises,
M = some mechanical failure in the PA system,
Mh = human-sounding mechanical failure
Mm = mechanical-sounding mechanical failure
S = human-like sounds
And let’s invent some numbers for a random flight:
P(H) = 1e-6 (feels too big to me)
P(M) = 1e-3 (feels a bit small to me)
P(Mm | M) = 0.995 (I.e. 99.5% of mechanical sounds sound mechanical)
P(Mh | M) = 0.005
We read an article about S happening so we now wonder:
P(H | S). Apply Bayes theorem:
= P(H) P(S | H) / P(S)
= P(H) * 1 / P(S), and in our model
= 1e-6 / P(S).
Now what is P(S)? We can calculate in our model (assuming we’re describing all possible causes and for simplicity ignoring a flight with a human-sounding mechanical failure and a prankster).
P(S) = P(H) + P(Mh)
= P(H) + P(Mh | M) * P(M)
= 1e-6 + 0.005 * 1e-3
= 6e-6
And we can plug that back into the equation above:
P( H | S ) = 1/6
You can fiddle around with the priors and get a feel for how the affect the results but the point I want to make is that it can be true that electromechanical sounds are very rarely human-sounding and still be likely that the sounds in this case are likely electromechanical. I believe that your argument was based on the incorrect logic I described at the start of this comment and not because you had strong priors that the very unlikely event of a human prankster was more likely than the combination of the unlikely events of a faulty PA system and a fault making humanoid sounds.
You're ignoring the fact that it's not just one production. I would consider your position if there was one continuous production with small to no variations.
Why are you ignoring the following?
- the sounds have the length of a yell or a moan.
- the silence between them is not fixed or related to any other sound that we can hear on the plane.
- there are no artifacts, except the weird pitch going up artificially in one of them, which might point to a prerecorded and manipulated sound
- if this was a electromechanical issue, it would have to mimic a significant part of the human anatomy, including a tongue (there are a few productions that sound like the throat is constricted and the tongue is rolling slightly).
Sure, a random electromechanical issue could have these characteristics, but isn't that extremely unlikely? You would expect other noises, not just the vocal-like sound.
Also I'm pretty sure I heard the sound of clearing the throat and spitting in the recording. Too many distinct categories of human-sounding sounds to be random electro mechanical or electromagnetic phenomena.
There was a post on Reddit, I think, that explained that there were ports in the luggage bins every so many seats that were for for medical comms to run on. Someone plugging something into this port could play whatever they wanted from a computer. It's probably the same person doing the same joke over and over.
The only problem for them is that AA could cross reference the travelers on those flights to figure out who it was, if it was a passenger using these ports to prank.
>Two indicator lights (red/green) serve as attention getters and ensure a far reaching call function when a respective message is displayed. The red light is used for system and emergency information, the green light for communication information. The lights are steady in normal situations and will flash in emergency situations.
>The ACPs give a long-range visual indication about the system status (e.g. PAX call active). They are installed at the ceiling in the middle of the aisle between the passenger/crew doors, close to
the attendant stations.
>The lighted segments are activated either continuously (steady) or flashing.
In case of "normal" calls they are not flashing (steady), in case of "abnormal" or "emergency" situations they will flash. Only the blue PAX call field will never flash, this will be always a "normal" indication
These indicator lights would be helpful in narrowing down if the emergency system was being engaged or not. Could potentially point to exploitation/hack of the PA system rather than rogue utilization of normal functions.
It could also be a maintenance person who has access to other parts of the plane. Did all the flights go through the same airport at any point? Or what if it’s something a flight attendant did? If so, it could even be flights through different airports.
This might narrow it down some, but I have been on weekend flights that I recognized people on the return leg from the away leg. But even going from 200+ people to 10 would help
The person doing it might not be on the affected flights. Instead they plant something on the plane during a different flight (or between flights if they are an insider who can get access to the plane between flights) that is hooked into the PA system and has a recording that it plays after a time delay or perhaps when the cabin pressure lowers or perhaps both (e.g., delay 48 hours than start when the cabin pressure lowers).
If the device had a long time delay or a delay based on the number of flights they might have to check many flights before the affected flight. And there is no guarantee the person would use the same delay each time.
If they pick flights on routes that have a lot of repeat travelers and the delays on the device make it so the airline has to look at a fews days worth of flights to get the suspects for each incidents then I'd not be surprised if there are may people that were on all the planes sometime before the affected flights.
The big problem I see with it being done by someone not on the flight is that surely after the first couple of times the PA system is going to get thoroughly inspected and the device would be found. The mystery would then just be "who", rather than the "how" mystery that we currently (at least publicly) have.
Pretty interesting. If it’s a hoax, it’s a pretty good one.
If it’s a hack of any sort someone is taking their life in their hands because being caught tampering with any commercial airline systems could mean significantly jail time. Cleaning crews and other staff have enough time on the plane to do something… I’m thinking like an Adafruit Waveshield with a timer or something.
If it’s a ghost, it seems like a horny adolescent one.
"Whoever ... causes to be made unworkable or unusable ... any part ... used in connection with the operation of such aircraft, if such placing ... is likely to endanger the safety of any such aircraft"
The "part" is the PA system. While the device is playing the prank sound, it is temporarily "made unworkable" for its intended purpose of allowing the crew to communicate with the passangers. This "endangers the safety of the aircraft" because in certain situations it's possible the crew would need to communicate quickly with passangers or have silence so that they can understand each other and focus on solving an issue.
Edit: Looks like captain could override, flight attendants couldn't. That still causes a safety risk because in an emergency the cockpit might want to focus on flying the plane while the flight attendants instructed the passangers. Plus the distraction factor remains.
I don’t deny that it’s an important safety system. I’m curious, though, if they’re treated like safety critical systems in design or if emergency training covers how to act if the PA is down.
I'd assume it's important to safety, but they have slightly less effective backups like yelling. I think the backup systems on aircraft are often things you'd rather not need to use.
Plugging in a Bluetooth transmitter into a user-accessible port and using the system as intended is "hacking" now?
Sure, passengers weren't intended to use that port, but from a system perspective the system is being used as intended with no interference or exploitation.
I'm not sure this system can even be "hacked" short of disassembling parts of the plane and tapping into the communications wiring.
We can debate if I've used "hacked" loosely without giving too much thought to my comment, but my point is that whoever did this (on a few flights, allegedly) has "gained unauthorized access to a computer system" (which broadly fits most definitions I find). Besides, unless I missed something we have no idea if they just paired with Bluetooth or did something else.
Maybe I'm off-base and they're just risking an airline ban, but it seems (to my uninformed opinion) that doing that on an flying airplane is playing with fire that the airline won't sue and that, if they do, it'll be a clement judge which won't make an example out of them for messing with an airplane's computer, safety critical or not.
Depending on the technical means used, it might not be proper to consider it to be hacking in, say, the CFAA sense, but you're still not supposed to do things that have the result of preventing a flight crew from making announcements to passengers. Even if you did those things with an otherwise perfectly legitimate means like playing a sound with a cell phone, playing a sound with a tape recorder, or playing a sound with your voice.
I would be happy to agree that the CFAA is overbroad. But disruptive actions toward flights and aircraft are quite reasonably punishable under other theories, when they could plausibly create a risk for aviation, regardless of the means.
I think a case could be made that it's unauthorized access, since the prankster is definitely not supposed to be using the system for those purposes, regardless of how accessible it is. Same as if you walked into a bank or something and surreptitiously plugged a malicious USB drive into one of their machines.
Maybe it would make a difference if the prankster was an employee, and not just some random person, but I doubt it.
Right. My comment didn’t assume a specific interface method (user accessible port / medical jack vs. something else) but rather a method to play the audio without having to be on the plane (which would certainly be my preference were I the prankster.) If it was actually done using a user accessible port intended for access to the PA, I would agree with you, it wouldn’t fall under CFAA/hacking type laws. Still could be problematic legally though.
Microcontrollers are small enough now that there could be lots of interesting ways to interface.
EDIT: Also, based on the OP, the PA gets power cycled repeatedly on at least one flight where this is happening. That’s much more intrusive.
It's literally only the media, and not the law enforcement, that use the term "hack." The word "hack" probably doesn't even exist in any criminal code.
Law enforcement use phrases like "unlawful access to a protected system" and whatnot.
49 U.S. Code § 46504 - Interference with flight crew members and attendants
An individual on an aircraft in the special aircraft jurisdiction of the United States who, by assaulting or intimidating a flight crew member or flight attendant of the aircraft, interferes with the performance of the duties of the member or attendant or lessens the ability of the member or attendant to perform those duties, or attempts or conspires to do such an act, shall be fined under title 18, imprisoned for not more than 20 years, or both. However, if a dangerous weapon is used in assaulting or intimidating the member or attendant, the individual shall be imprisoned for any term of years or for life.
I think the other statute is somewhat more relevant, because I'm not sure this is "assaulting or intimidating a flight crew member or flight attendant" (as it's more targeted against infrastructure than people!). I agree with the thought that a public address system is a "part" of an aircraft whose reduction in serviceability "is likely to endanger the safety".
You might argue that flight crew could be intimidated by the knowledge that their aircraft is behaving unusually, but I don't think that's particular core territory of "assaulting or intimidating".
* Unless someone had made dongle that once inserted looked like the same plugs, but raised enough to hide the dongle and match the color/texture of the surrounding plastic. The fake plugs on the outside would not even need to be functional and the device could be set to start on a delay, so whoever is placing them is not physically on the flight when it starts. It could even have an accelerometer to turn on after take-off and turn off on landing. If the person intentionally booked a seat at end of the plane, very likely they could easily add it when everyone is trying to leave the plane.
Credit card skimmers do something similar all the time:
This must be the explanation. The one thing I can't quite understand though is how someone could be simultaneously so very technically clever and yet execute such a mundane level of prank. This could be so much more epic if someone got more creative with the choice of audio track. I mean, it could be anywhere from totally hilarious to actual terrorism. Scary to think of the possibilities.
If this is truly the explanation though, I wonder if the public will ever get to hear confirmation or if they'll just remove it and refuse to talk about it / threaten employees to keep it quiet.
I wouldn't be surprised at all if this was the case - kind of like an internet flash mob all in on the joke, waiting for reputable news sources to pick it up and show their lack of journalistic integrity.
I mean, the only thing I could see them doing is asking the flight attendants or AA, but both of those are likely hard to get an actual answers for (AA would most likely say 'we are investigating' and would never follow-up). If something is on social media and there are enough corroborating accounts, it's probably enough to write a news article about.
> my go-to assumption when the source originates from Tiktok is to assume it's fake or staged.
Wise, although wiser to make that assumption for most sources. Until this starts being reported independently by more reliable sources then I assume it’s fake.
In this article the author claims to have talked to American Airlines about it:
>American Airlines inspected the Boeing 737-800 as well as the P.A. system itself after these reports. They tell me that maintenance “determined the sounds were caused by an issue with the PA amplifier. There was no external access to the system.”
> “determined the sounds were caused by an issue with the PA amplifier. There was no external access to the system.”
Hard to agree. Those sounds are almost certainly a human voice, presumably digitized. Unless the issue with the PA amp is that someone connected a sample player to it.
Yeah that is not an electrical hiccup in the audio - that’s a human. I am guessing Slavic by the inflection cadence. Also, Cozy Bear and all that.
Longtime guitarist, producer, film fanatic here and this is really going to be interesting.
It does remind me of last Halloween where I had my jumpsuit and hockey mask to be Jason Voorhies and I got a small mp3 player and looped an hour of “ki-ki-ma-ma-ma” lifted from YouTube and played thru a little amp on my porch. Play scarecrow and only move to scare the big kids or their parents haha.
It's getting shared on Social Media. People talk about it and likely never experience it. It's the same principle with the "creepy clowns" a while back.
Where did it say the source was from tiktok? They cited several separate Tweets about this same issue across multiple flights. They have recordings too
Maybe Instagram is worse but TikTok is full of the most dumb shit I can imagine, either that or people plugging their Instagram. There are smart people on it but they don't define the culture.
The immediacy of the format is amazing but the content is awful.
It tries to show me people talking about maths and finance and programming but they're all either infantilising themselves for some reason or not very good at it.
And anyway I have a fair amount of karma here so what does that say about hackernews if your implication is correct...
A lot of what I am complaining about is actually people older than me peddling "advise" - how to become a data analyst (no understanding of data required!).
It just feels like Facebook-tier people given the content equivalent of a machine gun.
If it’s this widespread then it either has to be AA maintenance (perhaps a team having a bit of reputational mutiny because AA management pockets tons of cash and exploits cheap contractors and constantly bitches about pilot pay but wouldn’t fly planes without pilots) or it’s remote.
As an audio person, musician, producer blah blah, that is totally human. Likely recorded and filtered a few times. By the inflections I think Eastern European. The sound of it reminds me of a Slavic based vocal upbringing. Doesn’t seem like North Korean, Latin, or North American to me.
Probably about a couple minutes of audio looping somehow at the source. Far too many for it to be a hardware exploit because honestly who wants to invest that much in this kind of prank? This isn’t Zug Super Bowl level[0].
My guess is they’re coming through the least secure provider for a third party service - probably the WiFi enterprise thru being on the inside of them - and AA is their first playground where people are noticing. How they get from there to the intercom is probably buried deep in a couple audio wires plugged into overlapping sources unintentionally or there is some kind of frequency band that isn’t shielded properly so it’s possible to push the audio signal over something else and cause garbled noise and almost impossible to find.
Like, in the past it was funny when picking up FM radio signals through my guitar amp, but it sucked when trying to have a serious jam session and talk between playing. Audio signals can be really powerful compared to other delicate systems IMO.
Definitely curious and want to see how this unfolds!
This reminded me of something that happened to me in college. This is a unlikely sounding story, but I swear it's the truth.
I started noticing some odd sounds in the Student Union building. One day I had some time and decided to investigate. I realized it was coming from a fire alarm. I stood under the alarm and listened for a while.
The alarm was quietly whistling "Harder, Better, Faster, Stronger" by Daft Punk.
I have a similar kind of fun story. The emergency phone on the elevator at work had a phone number somewhat close to that of an appliance store. People would call the number, the elevator phone would immediately put them on speaker phone. I figured this out one time I heard a faint phone breathing sound, and I started speaking with the caller. This happened again about once a year, and I had a fun time explaining to the callers that not only did they have the wrong number, but they had reached an elevator emergency phone. This response always caused a great deal of confusion.
Okay thank you for sharing - I answered a spam call on an elevator emergency phone once and I was puzzled but found it funny. So there’s an actual number…oh boy if only there was a registry…
Was there an AM transmission station nearby? Sometimes some metal objects can act as an antenna-speaker combo when there's a high power AM transmitter nearby. (some people have even reported this happening with dental fillings!) I'm assuming this is a bell or some other low-tech thing, if not there are probably many other explanations
This gives me an idea of an attack vector. These groans and moans seem rather quiet, and the airline claims its an amplifier issue. Assuming that the amplifier is not shielded from the cabin and that its analog tech, one could theoretically induce intentional interference to play whatever you want, right?
Not to my knowledge, but it's possible. There certainly wasn't a radio tower around, but there were antennae all over the place, as there are on any large campus. I don't think that's what was happening; it seemed to be different alarms at different times, but I believe it was always the same song. Which seems to me like they were being randomly selected by a script. These were fancy fire alarms and it was 2014, it's entirely plausible in my mind that they were networked and running a vulnerable embedded Linux. I don't think it'd be a Mission Impossible level effort to make this happen.
But, I'm going off of 8 year old memories, so the only thing I can say for certain is that it happened.
Someone in my engineering school opened the elevator panel and had it play a clip from the matrix (the full quote about there being no spoon) when you pressed a floor button.
Unsatisfying, Hanlon-style prediction: no one involved had any notable malice or competence.
Maintenance and cleaning crews love to listen to radio/music on speakers while working. Someone from this staff plugged in a receiver to listen while servicing the plane, and forgot it. Or they left it there for convenience and didn't think anyone would notice. Someone else unrelated, while on the flight, found this receiver on their phone/laptop, and played these sounds, possibly unwittingly.
AA may have found these devices after the incidents and just not reported it. Or they didn't take the reports seriously enough to comb the plane for problems. Or they gave up and would rather not lose the money by grounding the plane and tearing it down. (I don't have any aviation expertise, so I don't know exactly how disruptive it would be for them to to do this.)
This seems like the most likely explanation. Whoever left the device in the plane isn't likely to own up to it (if they even remember where they left it!) since they may lose their job.
The dongle idea is interesting but are we assuming someone is plugging in a dongle and making noises, on all these flights, sometimes for the duration of the flight and nobody finds these dongles?
Assuming it’s one person with the dongle responsible for all 3-4 instances of this - it would be pretty easy for AA to figure out who’s doing it if this is the case, just check if there’s a common passenger on every flight where the issue was reported
What's it jacked into, though? There are some amazingly flat card skimmers out there these days, and even cameras to place on ATMs that are disguised as panels. It could be something with a 1/8" form factor that just looks like part of the interior of the bin. For that matter, it could be a whole modified bin installed by a disgruntled employee.
it’s unlikely they’re doing this live, it would be way too obvious. The toilets would also be the first place they’d check. I’m guessing they’re using some recording.
You don't need physical access to interfere with an analog audio system. (Remember old cellphones?) Since they're saying it's an issue with the amplifier, I'm assuming someone found a weak spot that readily gets picked up by the system's input.
The audio might be analog, but they still have to "key" the mic which would be a digital input at the very least, or something even more complex such as a phone-like system where handsets have actual keypads and internal numbers.
I wouldn't expect the amplifier to be active at all unless a "call" is in progress (otherwise you might hear a constant noise, plus energy saving/thermal concerns and all that), so even if there was interference around, it shouldn't be getting amplified to an audible level unless something is actually "keying" the mic.
Yeah, I don’t believe the system is analog end-to-end. Moving the audio signal to every speaker across the entire length of the plane with analog seems like a fight against physics.
Maybe something in there is picking up the guard frequency. People make weird noises on that frequency all the time, including animal noises and screaming.
Not on purpose, but there are YouTube videos of pilots accidentally doing in flight announcements on guard. Maybe there's some plane error that is sometimes causing the error the other way around.
Why would there be a "medical intercom" as one quoted redditor suggested? Surely in the event of a medical emergency the crew can communicate about it with the same systems they use for everything else?
The medical intercom jack is often in the middle of the cabin (on equipped aircraft).
Flight attendants can plug in an aviation headset with a very, very long cord, and the pilots patch it into one of the radios in the cockpit. This allows the flight attendants to talk to a doctor on the ground while they're physically next to a passenger's seat.
> Flight attendants can plug in an aviation headset with a very, very long cord... This allows the flight attendants to talk to a doctor on the ground while they're physically next to a passenger's seat.
It may be to allow the flight attendants, taking care of the passenger, to speak directly to a ground crew without having to relay things to other people on the plane back-and-forth to the radio.
I’ve been on a flight where they used the medical intercom. Nobody is going to use it without a whole lot of people noticing.
And yes, it is there so the attendants can talk directly to medical personnel on the ground while attending to the person needing care.
PS - “intercom” is probably going to give people the wrong idea. It’s a headset with a thick black 50-foot long cord, and when you plug it in, it dangles down on top of passengers before getting to the aisle. Also, you can’t hear it - only the person wearing the headset hears anything…
> Nobody is going to use it without a whole lot of people noticing.
Well, if you make use of the complete system, sure. But if it just takes a regular TRRS jack; and if someone finds the socket and plugs their own headphones directly into it...
I'm late to the game BUT just in case someone sees this: Not so long ago they found that deep fake voices don't emulate the shape of the mouth and throat very well, and therefore it's easy to tell if a clip is a deep fake, or real.
They should be able to run these sounds through the same software to see if it properly emulates a throat and mouth or not.
Back in 2003 or 2004 I was at University and my best friend went there too, a year behind me so different lives.
He’s a brilliant software developer today and we ran amok digitally before the age of 18 and things really got serious. Free Kevin. We had that spirit.
I was playing music and hanging out with Mary Jane and he got a job with campus IT. Through his personal explorations he gained access to the Admin of the campus AV system. I mean the entire thing - if it was connected, he could control it. I doubt that was in his job description or assigned permissions, but I didn’t ask.
His way of proving it is you could tell him “I’m in Calculus II at 11-12:30 on Tuesday in Building X Room XXX” and at 11:55 the overhead projector would turn on magically but because it wasn’t connected to anything locally it was just the light. Off, then on again, then off for good.
A little disruptive but hey it’s higher education and that taught me a valuable lesson about willpower and mischievousness with a Kokopelli spirit.
Not necessarily. If I was to run a prank on airplanes, I would probably choose one airline. One one airline it can be dismissed as fake or an employee, etc. If it starts happening on multiple airlines, red flags start to go up all over the place and I would (theoretically, of course) start to be getting uncomfortably close to extremely hot water.
A lot of technical (practical?) speculation here, anyone any thoughts on the actual content or original source of the recording? To me it sounds like Buddhist chants like from those Buddha machines[0] or possibly some type of throat chanting. Can someone shazaam it? :)
It may be a wrong and long-stretch of an idea, but what if this is an audio being played into that headphones jack at a seat?
Directly, this should not be possible (input vs output on the amp), but in case the PA mic signal is routed to common amp after keying and preamp, this technically may be possible.
Now, if the "keying" includes some specific signal to allow the routing to PA, the question is if the "keying" signal can be sent from the seat's console. Then just play back the annoying track into the headphones jack.
Linked article appears to state the PA system is physically isolated — which I would assume means only known components of the PA system interact with each other:
>> Professional reverse engineer/hardware hacker/security analyst Andrew Tierney (aka Cybergibbons) dug up the Airbus 321 documents in this thread, and is stumped too.
I vaguely remember that PA messages are heard in headphones, so the PA signal is being patched through at some point.
It's not clear how the "seats" bus is isolated. I assume it's a bus, so that seats are addressable. The seats should at least be able to send the "need attendant" signal.
I hope a qualified technical analysis already pointed a few possible vectors for this. The question is in remediation and, well, identification of the perp(s).
Either way, at this moment the story seems to act more as an attracting magnet than repelling for the airline. Back during summer, it certainly was another level of annoying and disturbing.
Listen, pal, that's none other than protean blue checkmark Emerson Collins himself, well-known actor and producer of "Del Shores: Naked. Sordid. Reality" and "Southern Baptist Sissies". The voice you claim to be annoying is the instrument of a trained thespian.
Update. Emerson Collins found my comment in his daily Google alert, created an account, and downvoted me. Devastating. My only consolation is that the master knows who I am.
I know little about airplane tech, but do these onboard systems such as PA ever get OTA software updates? Perhaps an update got pushed that runs the prank? Could explain it happening on multiple flights and attendants being unable to stop it.
I think some kind of overlooked physical access to the system is the simplest explanation, since it would even effect an analogue system. Imagine there was some kind of mic input in the bathroom for some reason you could hook up a device to.
My understanding is that planes don't fly directly upside down, and they angle the wing slightly to make a kinda-sorta-airfoil.
How helicopters can turn directly upside down, and fly that way[1], without reversing the direction of their props, that I don't get. (Thinking about it now, I think it turns from a helicopter to a hovercraft? Eg, this is a ground effect?)
Jesus H. Christ, that brings back memories. When I was (much) younger, probably somewhere between 9-13 or thereabouts, I had a brief phase when I really in to "weird stuff." I spent a lot of time reading books about UFO's, ghosts, the Bermuda Triangle, the Philadelphia Experiment, "ancient aliens", the "Oak Island money pit", blah, etc. etc. And the whole Flight 401 thing either figured very prominently in at least one book I read, or it kept re-appearing or both, because I just recalled a whole bunch of profound feelings associated with that story. I remember being really freaked out by it at the time. Enough so that I probably wouldn't have wanted to get on an airplane had I had any reason to fly back then (I didn't).
I'd like to say that even back then I mostly didn't really believe all that stuff, but I think maybe I kinda did, at least to a degree. Now I think it's all bollocks, and maybe that's one of the things I miss about being a kid... that sense of fascination with the mysterious and unknown and the sense of possibility that comes with allowing yourself to believe in the Bermuda Triangle, ghosts, yadda yadda.
I'm with you on the last one, and I sometimes wonder whether religious people still have that sense of fascination with the unknown, or with what is possible.
I would like to have that again, if only for a few moments.
Lost souls on Boeing planes isn't too far fetched. Lord Xenu flew in all those thetans on rocket powered DC-8's which were originally made by McDonnell Douglas who merged with Boeing. Basically Snakes on a Plane but with souls and Tom Cruise.
An accidental time traveler traveling slightly out of alignment with their timeline would likely manifest as something we would describe as a ghost, for a brief moment.
I just listened to it, and it's obviously some teenager or 20-something that's hacked into it, maybe screaming from the bathroom, or added something to a memory card somewhere.
Interesting. I heard similar sounds from a rather big French train station speakers recently. For me it looks like it’s just a bug from the amplification system.
Goats yell like humans and we seem to recognize the sounds as human voices, even when they're not. It's probably a bad example, but maybe we "recognize" human voices even when they're not there. Similar to how we recognize faces everywhere that aren't really faces (e.g. the face on the moon).
But anyway, I'm playing devil's advocate with myself. I agree that's definitely a human voice on the intercom.
I would bet a large amount of money what you mentioned is entirely false. The PA systems are built into the aircraft, where as wifi is an aftermarket addon.
dont know anything about the sound systems of aircrafts, but why can’t they switch off each sound system one by one and see which one causes it and then see the possible inputs to the one where the sound is played? I assume it cannot be that hard to do during maintenance period especially if this happens on multiple planes.
Back when I was in college some twenty years ago, we somehow managed to stumble upon a phone number we could call that would connect us directly to passengers in some unknown elevator car in some distant city. We had great fun with that for a while.
Back when I was in elementary school near 30 years ago we discovered we could print to any printer in the district over AppleTalk. We printed so much garbage to so many printers.
I doubt the veracity of this account, at all. The liability from flying a malfunctioning, compromised plane is way too high for this to happen more than once.
Not an aviator, but planes can & do fly with malfunctioning noncritical components all the time. I don't know whether the PA system is considered critical or not, but it also didn't appear to be nonfunctional; the article said the pilots were able to use it & that their signal appeared to have a higher priority.
I don't know if this is true or not either, but I don't think we can reject it on it's face.
I have a friend who was a flight attendant for the oldest Mexican airline, and she indeed told me how sometimes, when there's a critical system malfunction before a flight, often managers call the pilots privately and offer a bribe to fly the plane with that malfunction. The pilot can refuse the offer without any problems or losing the job, but it's a bit scary to think that's there's corruption at that level.
Fortunately, planes are extremely robust and somehow Mexican airlines have an excellent safety record.
I was on a flight from Chicago to Raleigh a few years ago, and we were just starting to taxi out to the runway when the plane stopped and the pilot got on the PA and said something like "Sorry folks, we have a maintenance indicator (kind of like a 'check engine' light) that has come on. We have to go back to the terminal and get maintenance to check things out."
So we go back to the terminal, wait approximately 3 times longer than the expected lifetime of the universe (OK, that part might be an embellishment, but it felt like it at the time. The rest of this story is true though). Anyway, after a bit the pilot comes back on the PA and says something approximately like:
"OK folks, a $FRIZGIBBIT on this plane is broken. Thankfully these planes have two $FRIZGIBBITs and are certified to fly with just one working, so we're going to go ahead and get underway and get you all to Raleigh."
And that's just what they did. Frankly I was a bit nervous about the whole thing. I don't know what the hell a $FRIZGIBBIT is or what it does, and they say it's OK to fly with just one, but the way I figure it, somebody decided to put two in the first place for a reason. What if the remaining one breaks mid-flight??
Anyway, it all worked out in the end, or I wouldn't be here to tell this story, but the point is, planes do apparently fly on occasion with broken something-or-others.
My mother was a flight attendant on a flight where they thought the front landing gear didn’t come down. There were three independent systems on an L-1011 to detect this and all three agreed that the landing gear failed to extend. They did a tower flyby, and the tower said the wheels were down, so they operated under the assumption it wasn’t locked into place. The plane circled for a long time while emergency crews foamed the runway and positioned themselves for an emergency landing.
It turns out that all three independent systems malfunctioned and the landing gear was fine.
Since 9/11 and armored & locked cockpit doors, surely planes would be able to withstand pandemonium in the cabin and still land safely?
Also, in the video linked in the blog post there doesn't seem to be much panic visible at all. I bet most people are laughing their asses off once the initial confusion is over.
It doesn’t sound particularly human and it seems like it would be a weird hobby to go on a bunch of flights and cause these strange sounds. Surely a prankster would get bored and move on to something like music or silly messages. (And if the airline believed passengers were doing it they might correlate flight records or something?)
I think I’d probably believe that it’s just some elctromechanical issue. I doubt fixing the PA system is going to be in the pilot’s manual and I’d expect flight attendants to be basically incompetent in dealing with such an issue.
I think I would guess either an issue with some prerecorded announcements system (eg playing bits of messages at strange speeds and at random) or some kind of electrical interference or short-circuiting problem (eg some glob of solder bouncing around inside some unimportant component).
Sounds human to me too but I wonder if we've been primed by the headline to recognize it as such. If it had just been posted as "Mystery sound on American Airlines flights", maybe we would have interpreted it differently. This has worked on me before for backmasking and was quite remarkable how different what I heard between when I was primed and when I listened to the track a week later without priming.
the tonal inflections are very human, and in the recording it felt the voice changed a bit after the flight attendant made an announcement, so it's probably live (not necessarily making the sound, but using a soundboard).
There is no way this is mechanical or feedback-related. The sounds are just too varied. There's a point where the guy clearly says "raargh".
It's obviously someone messing around. I assume AA claimed it's a glitch because PR doesn't want stories going around about how their planes are hackable, but it just makes them sound untrustworthy.
It does not mention the "medical intercom jacks" in overhead bins that are mentioned at the end of the article
[1]:https://caisatech.net/uploads/XXI_3_AIRBUS_H51_A320_O_CCOM_R...