Definition
An automated position reporting method in which the aircraft's Flight Management Computer (FMC) generates waypoint passage reports and transmits them via the Aircraft Communications Addressing and Reporting System (ACARS) datalink to air traffic control or the operator, instead of the crew making voice position reports over the radio.
Plain English
The aircraft's onboard computer automatically sends a digital message each time the airplane passes a waypoint, so the crew does not have to read out position reports on the radio.
Context Anchor
Seen in RNAV departure discussions, procedure notes, or aircraft capability descriptions where route-progress reporting is handled electronically.
Derivation
FMC = Flight Management Computer (the aircraft's main navigation and flight-planning computer). WPR = Waypoint Position Reporting. ACARS = Aircraft Communications Addressing and Reporting System, a digital datalink between aircraft and ground stations. Put together, the term names the computer (FMC), what it is doing (waypoint position reporting), and the channel it uses to send the message (ACARS).
Why Pilots Care
Cuts radio workload, gives controllers exact real-time position data, and supports higher-density RNAV operations.
Intuition Check
Do not read this as one navigation system. The FMC manages the route, WPR is the waypoint position report, and ACARS is the message path to the ground.
Example Sentence 1
Once established on the oceanic track, the crew confirmed that FMC WPR ACARS was active so position reports would be sent automatically at each waypoint.
Example Sentence 2
ATC requested FMC WPR ACARS reports to maintain precise tracking during the RNAV departure.