Airplane Intercom Hacking: Mystery Solved?

Several days ago I wrote about a strange thing going on with the intercoms of some American Airlines jets. Initially this was a total mystery, though clues are increasingly pointing in a certain direction…

Reports of weird noises on airplane intercoms

The always insightful @xJonNYC has an interesting thread about some weird occurrences on American Airlines lately, involving the intercom.

The first report was from an American Airlines Boeing 737-800, where there were repeated hacking, moaning, and screaming noises over the PA. The flight attendants allegedly even stood by their phones throughout the cabin, to make sure no one was trying to use them.

@xJonNYC then shares what I assume are messages from some sort of flight attendant messaging board, with similar reports, containing even more details.

Here’s one report from a flight attendant on an American Airbus A321T, which is downright creepy:

• The pilot called back to the flight attendants to see if someone was trying to get in touch with the cockpit, since their phone kept going off; when they picked up, someone was breathing into the phone, but didn’t say anything
• Then the phone would start going off in the cabin, but when the flight attendants picked up, there was just a tone sound
• Then there would suddenly be loud breathing, groaning, and moaning noises over the PA, and “it sounded completely out of a horror film”
• Then the master power button near the forward left door would keep getting pushed, and would shut down all IFE and seat power outlets
• Allegedly the two business class flight attendants said they were on the same plane the other day, and the same thing happened
• The flight attendant said they had a visual of each flight attendant every time this would happen over the PA

There’s even video and audio of one of these situations.

Um, wow… that’s strange!

Was someone onboard playing a prank?

There were a variety of theories as to what could cause this, but almost all have been debunked:

• Some suggested that someone was using the jacks from the plane’s medical intercom, as this system has receive and transmit key controls; however, American Airlines jets no longer have these
• Some suggested that this was some sort of a pre-recorded announcement when an update was last made; however, given how sporadic this “glitch” is, and given that it involves multiple types of planes, that seems highly unlikely
• Some suggested this wasn’t even a human noise, but rather was an artificial noise; listening to the audio, it seems pretty clear that this is a human noise
• Some suggested this was some sort of a cybersecurity incident, but that seems virtually impossible, since these systems are hardwired with no external access and no Wi-Fi component

Following one of the incidents, American released the following statement:

“Our maintenance team thoroughly inspected the aircraft and the PA system and determined the sounds were caused by a mechanical issue with the PA amplifier, which raises the volume of the PA system when the engines are running.”

I don’t even know what that means, but I don’t buy it. Whatever these sounds are, this doesn’t sound like a mechanical issue with a PA amplifier. This sounds like someone playing a prank.

That brings us to an interesting update. @xJonNYC suggests that this incident will be solved and that it won’t happen again.

He also notes how in the video that was filmed of one such incident, you can clearly hear the “click” sound of a handset hanging up.

The most obvious explanation all along has been that a human onboard the flights is behind this, and it looks increasingly likely that this was the case. As I’ve said from the beginning, I’m curious if there’s a common person who was on all of these flights, whether a working crew member (less likely) or a non-rev or revenue passenger (more likely).

Now, admittedly flight attendants claimed that they had eyes on all phones in a couple of these instances, though I suspect that this is the detail that’s least likely to be accurate.

I would guess that this was a passenger rather than a crew member, simply because a crew member probably wouldn’t jeopardize their job in this way. This does make me wonder what punishment a passenger could face for this. You’d think that interfering with aircraft systems, calling the cockpit, etc., would be punishable as a crime, no?

And what was this person’s motive? I assume it was just to screw with people and to see what they could get away with, though that’s really not cool, if so. Furthermore, this seems really risky — this happened multiple times per flight and on multiple flights, so it’s kind of unbelievable this person was never caught.

It almost seems like this might have been an American Airlines non-rev, based on the fact that this happened on different kinds of American Airlines planes, but most commonly on the Airbus A321T. This is American’s premium transcontinental jet, which is really popular with non-revs (given the ability to score first class seats).

For the reports of the master power button (near the front left door) on A321Ts being turned off, it would also make a lot more sense that this was someone in first class, since they’d be close to that.

Surely a non-rev wouldn’t risk their privileges by pulling this prank, though?

Bottom line

There have been several reports in recent weeks of weird noises on American Airlines intercoms. While there have been all kinds of theories, by process of elimination it seems increasingly likely that this was in fact a case of someone onboard simply using the PA to make these noises.

That seems to be the direction of @xJonNYC’s thinking, and I’m inclined to think he’s correct (because he usually is). Since this is a saga many of us have been following along with, hopefully we get to learn about the conclusion, and who was behind this. I’m curious if this leads to an arrest or not.

What do you think — was a passenger onboard simply playing a prank with the PA?