Pilots and cabin crew use specific secret phrases and discreet signals to communicate emergencies quietly during flights without causing passenger panic, according to aviation experts.
Frequent flyers often encounter these terms on travel websites, but aviation experts emphasize that internal codes vary by airline and are not standardized across the industry.
Discreet communication allows flight crews to coordinate rapidly during incidents without creating unnecessary anxiety in the cabin. Experts explain that a public announcement about a serious issue could cause confusion or block flight attendants from reaching passengers who need urgent assistance.
Medical emergency codes on flights
Among the phrases used by certain airlines is Code 300, also referred to as Angel. In some airline protocols, this term indicates a severe medical emergency, such as an unresponsive passenger or a death on board, though exact definitions depend on the carrier's internal policies.
A less critical medical situation may be flagged using Code Yellow. Airlines use this term for minor medical issues requiring crew attention, though it is also non-standardized across commercial carriers.
Commercial airline crews receive medical and first aid training to assist passengers before landing, where ground emergency medical teams can take over. Maintaining clear internal codes helps crew members manage onboard medical events efficiently.
International urgency signals and passenger habits
Unlike company-specific phrases, Pan-Pan is an internationally recognized urgency signal across global aviation. It indicates a serious situation demanding immediate attention, but one that does not present an immediate threat to life or the safety of the aircraft.
The signal Pan-Pan derives from the French word panne, meaning a breakdown. It is distinct from Mayday, derived from the French m'aider, which is reserved exclusively for severe distress where life or the aircraft is in immediate danger.
The list also includes the unusual term Mermaid. According to Travel + Leisure, a travel magazine, cabin crew use this phrase to describe passengers who deliberately spread out across empty seats to occupy an entire row.
Chimes and what passengers should do
In addition to spoken terms, flight crews regularly use audio chimes and internal communication routines to signal different flight stages or alert colleagues.
Experts advise passengers who hear an unfamiliar phrase or chime to remain calm and follow all instructions from the crew, noting that passenger safety remains the top priority on every flight.
