Accès aux contenus de la page (appuyer sur "Entrée")

Contaminated runways & runway condition reporting

27 octobre 2016 (mis à jour le 28 octobre 2016) - Transports

In need for improvements


Jean-Marc Flon
General ATS manager Paris-CDG

This issue is of utmost importance for air navigation services as controllers are a fundamental link in the process. Be it in terms of assessment solicitation, information transmission to crews or PIREP solicitation and collection in order to facilitate updated and reliable runway contamination assessment, correlated to aircraft braking performance. Processes have to be understood and mastered by all front line actors so as to ensure trust in these processes which is an essential component to allow performance and resilience of a system already under strain in these adverse operating conditions.


Following various incidents and accidents related to misreported, misleading or incomplete runway surface characteristics, it became obvious that a common understanding and a common reference of the runway surface condition assessment was needed.

Flight crews expectations and constraints should be at the heart of the runway condition assessment process. Trust in the process and reliability of the data has to be achieved in order to ensure its operational use.


How slippery is the runway ? What do aircrews expect ?


Aircrews need Runway Condition Reports that will ensure situational awareness at all times.

  • Getting through the most reliable and tangible information
    • Information needs to be clear, accessible in a unique format and regularly updated.
      Correlation needs to be sought between the runway surface condition as expressed in the runway condition report and the braking action as anticipated by flight crews.
    • ATC and pilot phraseology needs to be standardized to ensure understanding and consistency.
    • Airport operators should work towards harmonization of processes and means to assess the runway contamination.
  • A flexible regulation to match the various airport contexts
    A new flexible regulation will help identifying the means to update the runway condition report and processes. The objective is to acquire homogeneous and standardized data. The process cannot be the same at Paris CDG, where the traffic pressure is high, or on a smaller airfield where you can for example clear the runway before the next arrival. The final runway condition code depends on the airport operator’s expertise, but the outcome of the process must have a unique format all over the world.
  • Encouraging Research & Development
    The need for support tools to fine-tune the runway condition reports.

The aircraft itself should become a sensor and thus complement the existing measurement means, providing regularly updated data on braking capability without impinging on runway operations. The information should be made available system to system to all other flight crews, providing that their aircraft is equipped.


The TALPA trials – Take-off and Landing Performance Assessment, the way forward


After years of study, ICAO recently published a set of amendments to implement a new reporting format by 2020, based on the US TALPA-ARC methodology.

The concept relies on the use of a table called Runway Condition Assessment Matrix which includes a harmonized set of criteria for the description of the runway surface and the correspondence with the Runway Condition Code. Moreover, downgrade adjustments are possible when data from pilot reports, friction testing or simply visual observations, suggest that conditions are worse than the previously-assessed contamination state.
DGAC has carried out TALPA trials on 12 different airports including Paris CDG, Paris ORLY, Bâle Mulhouse, Lyon and Strasbourg during 3 winters between 2014 and 2017 (period from November to April). These trials were based on data collection (contaminants and PIREP).

The objectives of the trial are :
• validating the correlation between the Matrix surface condition descriptions and pilot braking action reports (PIREP),
• testing the operational use of the Runway Condition Assessment Matrix with participating airport operators and pilots.

What have they demonstrated ?
(winter 2014/2015)
The correlation was encouraging, but the crucial importance of a consistent dissemination of the information was confirmed alongside with the need for the aircraft to complement the existing measurement means.

TALPA improves the way the aviation community assesses the runway conditions, based on contaminant type and depth. It provides crews with effective data to anticipate the airplane braking performance.