Definition
Equipment installed on an aircraft that broadcasts the aircraft's position, identification, and other flight data to ground systems and to other aircraft. The most common examples are the transponder and the ADS-B Out unit, which together allow ATC and nearby traffic to see and identify the aircraft electronically.
Plain English
The pieces of gear on board the aircraft that tell the outside world where the aircraft is and who it is. Without these working, the aircraft is much harder for controllers and other pilots to see on their screens.
Context Anchor
You may see this term in ATC or FAA guidance when discussing speed control, approach spacing, landing, or how an aircraft is configured for flight.
Derivation
“Aircraft” means a craft that travels through the air. “Device” comes from an old word meaning something designed or arranged for a purpose. In this term, the useful idea is that these are built-in aircraft parts used for a specific flying or stopping purpose.
Why Pilots Care
Regulatory compliance and airworthiness depend on having the correct devices installed and functioning; missing or inoperative devices can ground the aircraft or limit operations.
Intuition Check
Do not read “device” here as any gadget or electronic item in the airplane. In this FAA context, it means aircraft equipment that affects how the aircraft flies, slows, or stops.
Example Sentence 1
Before entering Class B airspace, the pilot confirmed the aircraft devices were on and transmitting correctly.
Example Sentence 2
Maintenance logs list every aircraft device that was inspected during the annual.