Push-to-Talk (PTT)

Definition

Push-to-Talk (PTT) refers to the function of activating the aircraft radio transmitter by pressing and holding a button during voice communication. PTT ensures that only one party transmits at a time on a given frequency, maintaining clarity, control, and order in aviation radiotelephony.
PTT is typically activated using a yoke- or stick-mounted switch, a panel-mounted button, or a handheld microphone.

Purpose

  • Allow the pilot to control when they transmit on the radio
  • Prevent simultaneous transmissions that cause interference ("blocking")
  • Enforce concise, intentional communication
  • Maintain radio discipline and reduce congestion on busy frequencies

How PTT Works

  • Pilot presses and holds the PTT switch to transmit
  • While the switch is held, the microphone is live, and ATC or other aircraft can hear
  • Upon release, the system returns to receive mode, allowing incoming messages
  • Only one transmission can be clearly received per frequency at a time

PTT Configurations

SetupUse Case
Yoke/stick-mounted buttonMost common in GA and commercial aircraft
Hand mic with PTT switchUsed in older aircraft, backup systems
Helmet-mounted PTT (military)Hands-free use in tactical ops
Dual PTT (pilot/copilot)Shared radios with independent controls

Best Practices for Using PTT

  • ✅ Plan what to say before pressing
  • ✅ Press–pause–speak: wait half a second after pressing before speaking
  • ✅ Speak clearly and steadily
  • ✅ Release button after speaking to hear reply
  • ❌ Don’t press the button while thinking or hesitating
  • ❌ Avoid long transmissions or overlapping calls

PTT Phraseology Example

Press PTT: “Salzburg Tower, OE-XYZ, ready for departure runway 15.”
Release PTT
Wait for response before pressing again

Radio Blocking

If two aircraft transmit simultaneously, ATC may hear a garbled or unreadable message, known as blocking. This usually results in:

  • “Two aircraft transmitting simultaneously, say again.”
  • Pilots must pause and repeat their message individually.

Emergency Use of PTT

In urgent situations, concise use of PTT is critical:

“Mayday, Mayday, Mayday, engine failure, OE-ABC, 5 miles west of LOAV.”

Don’t hold the button for extended explanations — keep it clear and short.

Tips for Pilots

  • Practice smooth, confident use during LearnATC simulations
  • Always check mic and PTT function during preflight
  • Avoid “hot mic” errors by releasing the button after speaking
  • Stay silent unless necessary — the airwaves are shared