Emergency Descent & Depressurisation

What this scenario covers

1. Exchange 1

   Masks on, descent initiated. Make the MAYDAY to Denver Center: MAYDAY three times, callsign, emergency descent, and that you are squawking seven seven zero zero.

   💡 A rapid depressurisation is a distress — MAYDAY, not PAN. Squawk 7700 alerts every ATC unit even before you speak, and stating "emergency descent" plus leaving level gives the controller what they need to clear the airspace beneath you.

2. Exchange 2

   You are descending through busy airway levels and may not have positive separation. Broadcast the emergency descent to all stations / surrounding traffic.

   💡 An emergency descent can take you rapidly through other aircraft's levels. A general "all stations" broadcast of your descent and level warns nearby traffic directly, backing up ATC — repeat the key words so a partially-blocked transmission still carries the warning.

3. Exchange 3

   ATC: “Speedbird two four five, Denver Center, roger MAYDAY, descend and maintain one zero thousand, altimeter three zero zero one, say intentions.”

   Read back the assigned altitude and altimeter, then request vectors to the nearest suitable airport. Altitude and altimeter are mandatory readback items.

   💡 Even in an emergency the altitude and altimeter setting are mandatory readbacks — they keep you separated from terrain and traffic once you level off. Airline callsigns are never abbreviated: it stays "Speedbird two four five" throughout.