Presidential Aviation, a US carrier operating under ICAO code PRD and callsign PRESIDENTIAL, currently shows no flights on live flight tracking systems.
Original report
airplanes.live
The gap highlights how public tracking coverage of business-aviation carriers can vary, affecting real-time visibility into charter and executive flight activity.
Presidential Aviation, a United States-based carrier operating under the ICAO code PRD and radio callsign PRESIDENTIAL, currently has no flights visible on the live flight tracking network. The airline's real-time flight data is normally monitored through public tracking systems that display callsign, registration, aircraft type, altitude, and speed. Presidential Aviation's designator and radio telephony data are sourced from the FAA JO 7340.2 Contractions publication, Chapter 3 Section 3, which lists ICAO three-letter company designators.

AVI-GO, “Presidential Aviation (PRD) Currently Has No Active Flights Visible on Live Tracking Network”. https://ai.avi-go.com/news/ai-news-center/news-briefs/presidential-aviation-prd-currently-has-no-active-flights-visible-on-l-0142a0023ee58c64c36b5f0680894c37
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