Besides MAYDAY, there are scores of communication codes and signals used by pilots and cabin crew members both off and on ground, as well as by the Air Traffic Controllers (ATC) in flight operations.
MAYDAY: A pilot repeats MAYDAY thrice to clearly communicate with the air traffic controller (ATC) on the ground that the aircraft is in a life-threatening situation and needs urgent help.
PAN-PAN is another distress signal used by pilots to seek ATCs’ help when there is some emergency onboard the aircraft, but it does not signify any life-threatening risk to passengers or crew members in the immediate term.
GPW S: It is a signal in the cockpit that alerts the pilot if the aircraft is in immediate danger of flying into the ground (terrain) or some object.
ARMING THE DOOR: Activating the emergency escape slides (chutes) for their automatic deployment if the door is opened in an emergency situation. This helps in quicker passenger evacuation.
DISARMING THE DOOR: Deactivating the automatic deployment of emergency evacuation slides mechanism when the door is opened.
NOTAM: A Notice to Airmen (NOTAM) is an official communication issued by aviation authorities to inform pilots and aviation personnel about temporary or urgent changes that may affect flight safety or operations.
GO AROUND: Also called a missed approach, happens when an aircraft, during the final approach for landing, aborts landing, climbs back to come back again and land or divert to another airport.
ABORTED OR REJECTED TAKE-OFF: When the pilot decides not to continue with the take-off roll and brings the aircraft to a stop at the runway.
V1: The speed of aircraft beyond which there’s no turning back, a takeoff decision speed. Once V1 is reached, the decision is made: the takeoff must continue, even if there’s a problem. A pilot has to take off the aircraft, get airborne and come back and then land in case of some emergency.
V2: The speed at which the aircraft gets airborne.
RUNWAYS INCURSION: An incorrect presence of an aircraft, vehicle or person on the designated area of the runway for landing.
RUNWAY EXCURSION: An aircraft going off the runway either by veering off or overrun.
CAT III: It refers to a type of instrument landing system (ILS) approach that allows aircraft to land in conditions of very low visibility such as fog, rain or snow with a runway visual range (RVR) of 50-200 meters.
CATII: A precision instrument approach with an RVR of not less than 350 meters.
