What the sounds and announcements you hear on the plane mean

You're sitting in your seat, the plane is going up, and at one point you hear a ding. Then another one. Then the flight attendant gets up from her seat and starts moving. What happened? What about that double ding from before takeoff? And the captain's announcements in that flat, soothing voice saying the same things over and over again?

There is a definite system behind this, and understanding it transforms flight from a sequence of mysterious sounds to something much more readable.

I ding: coded messages for the crew.

The sound you hear most often in flight is not aimed at you. The dings they hear in the cabin Are coded messages between pilots and flight attendants, and each airline has its own system. The meaning changes depending on the number of sounds, the tone, and the time of the flight when they occur.

In general, during the critical phases of flight, viz. take-off and landing, there is what is called a "sterile cockpit": pilots are focused on procedures and cannot be disturbed. When the aircraft exceeds the 3,000 meters or so uphilla, the sterile phase ends and a ding signals the cabin crew that they can get up, begin duty and contact the flight deck if necessary. The same sound, on descent, signals a return below that altitude and alerts the flight attendants to prepare for landing.

A single ding in most companies corresponds to a call from a passenger's seat when someone presses the button on the seat. A double ding often signals communication between the cockpit and the attendants, or between the attendants themselves. Three dings below, on many companies, indicate an important warning such as theentry into an area of turbulence. On some companies, the captain uses dings even for more mundane communications such as asking the crew for coffee, without having to use the intercom.

The seat belt sign

La seat belt light on is the easiest signal to interpret: buckle up. But there are nuances worth knowing. The signal always comes on during takeoff and landing, but during the cruise phase the commander manages it according to weather conditions and to the received turbulence data. When it comes on suddenly during the flight without your going through clouds or rough air, it means that the commander has received information from other aircraft or air traffic control about an area of incoming turbulence. This is not a warning signal; it is prevention.

Commander's announcements

The commander talks to passengers at specific times such as before take-off with flight information, during cruise for weather and route updates, and during descent to announce landing. The tone is always calm and controlled, and this is not accidental. I pilots are trained to communicate so that passengers are not alarmed even when things are complicated.

Some recurring phrases have a more specific meaning than they seem. "Slight turbulence in the next stages of the flight" is a way to prepare passengers without creating anxiety, but it also means that the captain wants everyone in their seats with their seatbelts fastened before they start moving. "We are experiencing a minor delay due to last-minute documentation" is often the diplomatic way of saying that there is a minor technical problem to be resolved or that you are waiting for takeoff clearance. The expressions "area of weather" or "area of disturbance" is the way pilots use to indicate a storm, avoiding the word that might cause concern.

The "arming the slides" ad.

One of the announcements that many people hear without understanding is what flight attendants exchange just before the doors close: "arm the slides and confirm" or, in English, "arm doors and cross-check". It means that each flight attendant arms the inflatable slide mechanism of the door to which he is assigned, and then checks that his colleague has done the same with the neighboring door. It is a mandatory safety procedure in fact if the doors were opened in an emergency with the chutes cocked, they would automatically inflate to allow evacuation. After landing, the reverse announcement to "disarm the chutes" is heard to prevent them from accidentally inflating when the doors are opened normally.

Internal communications you don't hear

In addition to dings and microphone announcements, the crew continuously communicates through the aircraft internal telephone system. Pilots can call flight attendants and vice versa, without passengers hearing anything. It is over this system that the most sensitive information passes, such as warnings about passengers who are behaving problematically, medical requests on board, or updates on the flight situation that the captain prefers not to broadcast via intercom.

Next time you get on a plane, listen more carefully. That ding you thought was random almost always has a specific reason, and knowing what it means makes flying a less opaque experience and, for those with flight anxiety, also much less worrisome.

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