Global Reporting Format (GRF)
Global Reporting Format (GRF)
The Global Reporting Format (GRF) is a globally harmonized methodology for assessing and reporting runway surface conditions. The GRF was developed by the International Civil Aviation Organisation (ICAO) to help mitigate the risk of runway excursions. The GRF is applicable globally on 4 Nov. 2021 after being delayed a year because of the COVID-19 pandemic.
The GRF has its origins in the U.S. Federal Aviation Administration (FAA) Take-off and Landing Performance Assessment (TALPA) Aviation Rulemaking Committee (ARC) and subsequent initiative. The TALPA ARC was formed in December 2005 following a fatal runway excursion at Chicago Midway Airport. Its purpose was to make recommendations on improving the safety of operations on wet or contaminated runways for both takeoff and landing.
The ARC’s primary recommendations were:
- To use a runway condition assessment matrix (RCAM); and
- To ensure the use of common terminology by all parties involved in the process of determining and reporting the runway surface conditions and their effect on airplane performance.
ICAO began work on what became the GRF in 2008 with formation of a Friction Task Force comprised of 10 member states and seven international organisations, and supported by various panels and expert groups.
The basic GRF procedure is as follows:
- An assessment of surface conditions is made by a trained observer who, using a globally harmonized runway condition assessment matrix (RCAM), allocates a runway condition code (RWYCC) to each third of a runway.
- The code is complemented by a description of surface contaminant, including type, depth and amount of coverage, again using a harmonized set of descriptors.
- The RWYCCs, which range from 0 for a very slippery surface to 6 for a dry surface, and the descriptors are then used to complete a Runway Condition Report (RCR).
- The RCR is forwarded to air traffic services and aeronautical information services for transmission to the flight crew by SNOWTAM, ATIS and if necessary radio broadcast;
- The flight crew correlates the RCR with aircraft performance data, which enables them to calculate their takeoff or landing performance.
- Also included is a feedback mechanism for the flight crew to provide their own observation of runway surface conditions, confirming the RWYCC or alerting to changing conditions.
The GRF methodology is intended to cover conditions found in all climates and to provide a means for aerodrome operators to rapidly and correctly assess runway surface conditions, whether they are exposed to wet runway conditions, snow, slush, ice or frost. Because not all aerodromes typically experience severe winter weather (such as snow and slush), not all of the RWYCCs will be used by all aerodrome operators.
The Global Action Plan for the Prevention of Runway Excursions (GAPPRE) makes the following aerodrome-related recommendations relevant to runway surface condition reporting:
- Ensure that the procedures to assess runway surface conditions according to the GRF include reactive as well as proactive surface assessment to make sure hazardous changes are all identified and communicated in a timely manner.
- Ensure robust procedures are in place for communicating information regarding changing surface conditions as frequently as practicable to the appropriate services according to the GRF. Roles, responsibilities of stakeholders and coordination procedures should be formalised.
- Runway condition codes assessed should be compared against braking action reports by the pilots to ensure the accuracy of the information provided to the pilots.
- Runway Surface Condition Reporting
- Runway Surface Friction
- Surface Friction Measurement and Prediction in Winter Operations
- Global Action Plan for the Prevention of Runway Excursions (GAPPRE)