Runway Surface Conditions: The Global Reporting Format

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Runway safety-related accidents and incidents are aviation’s number one safety-related risk category, with 59 reported accidents in 2016, of which more than half were due to runway excursions, according to  ICAO iSTARS data.

A runway excursion is defined as a “veer off or overrun of the runway surface”, which can happen during landing or take off. One main contributing factor involves adverse weather that results in the runway surface being contaminated by snow, ice, slush or water, with a potentially negative impact on an aircraft’s braking, acceleration or controllability.

To help mitigate the risk of excursion ICAO has developed a harmonized methodology for the assessing and reporting of runway surface conditions. This methodology, known as the Global Reporting Format (GRF), will be globally applicable from November 2020, with deployment activities now underway.

Runway Excursion Accidents 2008-2016 (Source ICAO iSTARS)

The GRF is intended to cover conditions found in all climates. It provides 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, including rapidly changing conditions such as those experienced during winter or in tropical climates.

The GRF comprises an evaluation of a runway by human observation (normally done by airport operations staff) and, using a runway condition matrix, the consequent assignment of a Runway Condition Code (RWYCC). This code is complemented by a description of the surface contaminant based upon its type, depth and coverage for each third of the runway. This evaluation should, of course, be performed by a trained runway assessor.

The outcome of the evaluation and associated RWYCC are then used to complete a standard report called the Runway Condition Report (RCR) which is forwarded to air traffic services and the aeronautical information services for dissemination to pilots.

The runway condition matrix (used to assign the RWYCC)

Pilots use the RWYCC to determine their aircraft’s performance by correlating the code with performance data provided by their aircraft’s manufacturer. This helps pilots to correctly carry out their landing and take-off performance calculations for wet or contaminated runways.

Another important element of the GRF is a process that enables pilots to report their own observations of runway conditions, thereby confirming the RWYCC or providing an alert to changing conditions.

Other key qualities of the GRF are its relative simplicity and its global applicability. A methodology that is easily understood and implemented globally is an important means by which the runway excursion risk can be mitigated and the safety of runway operations improved.

Finally, as we prepare for the applicability date in 2020, the importance of awareness, education and training is not being overlooked by ICAO. This need is being addressed through an ICAO/ACI symposium to be hosted in Montreal 26 to 28 March 2019 (event website and registrations at:, with follow-up through more focused regional seminars. In addition, training resources are being developed, initially for airport operations staff, but eventually also for pilots and air traffic control staff.

About the author

Paul  Adamson joined ICAO as a technical officer on a four year secondment from EUROCONTROL, where his last position was Head of Airports for the Network Manager. Previous to that he was responsible for runway safety and A-SMGCS projects in EUROCONTROL. He also spent four years on secondment to the SESAR Joint Undertaking, where he was the programme manager for the SESAR airports-related activities and prior to that, he was an air traffic controller and he has an M.Sc. in airport planning.