ATC and emergency datalink
Clearances and instructions sent as text instead of voice, plus the coordination that flares up the moment a flight has a problem. Related systems like CPDLC ride on the same datalink.
Company and free text
Notes between the crew and the airline. Diversions, crew matters, gate info, and the occasional plain message you would not expect to see.
Maintenance and engine data
Automatic fault reports and performance numbers sent to the airline, so the ground can act before the plane lands.
Position reports
Where the aircraft is, on a schedule or on request. Useful over oceans and remote areas where radar is thin.
Weather
Requests and replies for airport conditions and forecasts, often handled automatically by the aircraft.
Operational events
The routine timestamps and status pings that track a flight through its day. Common, and the least interesting part of the firehose.
You do not need to memorize any of it. Flight Deck reads the label, sorts the message, and shows it in words. For the basics, start with what ACARS is, or see what pilots send in practice.
Skip the labels, read the message
Flight Deck decodes every ACARS type for you on iPhone. Free on the App Store.
Download Flight Deck