Pilots frequently use mayday to signal emergencies in popular entertainment, but have you ever wondered what it actually means?

Mayday is derived from a French word, and it means “help” or “help me”.

Pilots say mayday three times during emergency situations to alert Air Traffic Control and request guidance and assistance from them.

Although mayday is the most famous emergency call sign, there are several others like ‘pan-pan’ that pilots also use in different emergency circumstances. 

What Does Mayday Mean in Aviation?

Mayday is used to signal a distress call on radio, and it’s universally recognized for this purpose.

People on board ships and planes use mayday to signal life-threatening emergencies, but it’s also used for other situations. 

In aviation, a distress call will include mayday repeated three times, after which the distressed party provides relevant information. Mayday calls may even be sent by one aircraft on behalf of another one. 

What is the Origin of the Mayday Call?

The mayday call was developed in the 1920s, and it was first used by Frederick Stanely Mockford.

Mockford was a senior radio officer at the now defunct London Croydon airport.

Senior officers at Croydon airport told Mockford that they needed a call that could be easily understood to both pilots and ground staff during emergencies. 

Mockford derived mayday from a  French term:  ‘venez m’aider’, which translates to ‘help me’.

What Does Heavy Mayday Mean in Aviation?

Heavy mayday is not an official term, although it is used by many pilots to indicate extreme difficulties.

Pilots conventionally use heavy mayday when their plane is close to crashing or suffering other extreme failure.

The “heavy” in heavy mayday is only used for emphasis and does not have any technical meaning. So it’s just an unofficial expression. 

For example, United Airlines Flight 328 made an emergency landing at Denver airport in 2021.

The pilot was heard saying “Mayday, mayday, heavy mayday” to Air Traffic Control while stopping his plane from crashing.

The use of ‘heavy’ was only intended to emphasize the degree of danger the plane was in. 

Why Would a Pilot Say Mayday?

Pilots say mayday when their aircraft is experiencing an incident, and they need to inform the authorities.

Pilots also provide incident-related information and identification of themselves and their aircraft during mayday calls to receive better assistance. 

Specific situations where pilots would say mayday include during engine failure, hydraulic failure, electrical fires, or malfunctioning components.

Providing this information to Air Traffic Control makes it easier for them to assist the pilots. 

In a majority of cases, pilots will only issue mayday signals when their aircraft is under threat of crashing or other severe incidents.

Other signals are used when an incident occurs but is not dangerous enough to threaten crashing the aircraft or causing loss of life. 

Why Do Pilots Say Mayday Three Times?

Pilots conventionally say mayday thrice for clarity and to ensure the message is heard.

Another reason is to prevent confusion between a mayday call and a message about a mayday call.

If mayday calls aren’t immediately recognized and assistance is immediately provided, there could be loss of life or damage to the aircraft.

 Pilots have to quickly and effectively complete mayday calls to ensure their message is unambiguously understood.

Saying mayday thrice has been found to be the best way to ensure the message is clearly understood. 

How Do Pilots Say the Mayday Call Correctly?

Pilots use the following convention for making mayday calls during emergency situations. They should include as many of these elements as they can, and in the stated order, but it is not strictly required. 

  1. Mayday mayday mayday 
  2. Name of station 
  3. Aircraft identification 
  4. Information about the emergency 
  5. Weather conditions 
  6. Pilot intentions 
  7. Current or previous position and trajectory 
  8. Altitude of plane 
  9. Remaining fuel in minutes 
  10. Number of passengers 
  11. Any other relevant information

After providing the above information, pilots receive instructions and advice from Air Traffic Control.

Pilots are permitted to ask questions or clarify instructions from Air Traffic Control.

Pilots are also required to not change frequencies or contact other ground stations unless absolutely necessary.

What Are Some Other Urgent Calls Pilots Use?

Although mayday is the most known emergency call, the following three are also used under different circumstances. 

  • Pan-pan

Pan-pan is derived from the French “panne”, meaning breakdown.

It is used for urgent situations like mechanical failures or medical problems that aren’t life-threatening.

So, pan-pan would not be used for an aircraft that is about to crash.

It’s only used for emergencies that won’t potentially crash an aircraft or cause serious loss of life. 

  • Declaring Emergency

Sometimes pilots declare emergency instead of calling ‘mayday’, but it is not an official term.

The international Civil Aviation Organization even recommended using ‘pan-pan’ and ‘mayday’ instead of declaring an emergency.

There have been many cases of confusion caused by pilots declaring emergencies instead of using “pan-pan” or “mayday”, so it’s heavily advised against. 

  • Seelonce Mayday

Seelonce mayday is used to request that the channel only be used for aircraft involved in the mayday incident.

When seelonce mayday is issued, a channel won’t be used for normal working air traffic until the case is resolved.

Seelonce mayday is rarely used these days, but it remains a valid emergency signal. 

In conclusion, mayday is an emergency signal that pilots use when their aircraft is in imminent danger.

The term was developed in the 20th century, and it is derived from the French word for help.

Pilots use mayday when their aircraft is in danger of crashing, or is otherwise threatened by grave or imminent danger.