What is GRF?

Last November there was a global change in how runway surface conditions are reported to Air Traffic Control (ATC).

This?harmonized methodology,?known as GRF (Global Reporting Format), is used?for assessing and reporting runway surface conditions. GRF mitigates the risk of runway excursions by including a more detailed way of reporting.?

Historically, runway surface conditions were reported to ATC as ‘Wet or Dry’. Now, however, it is reported numerically. Runway surface conditions have always been reported in 3 parts (for instance, Dry, Dry, Dry, or Wet, Wet, Wet – not the band). In the new GRF world Wet, Wet, Wet could be reported as 3/3/3 (Wet Runway). These codes are made up as part of the assessment criteria, below.