Winter runway condition descriptions updated
General aviation pilots will need to familiarize themselves with the new language that goes into effect Oct. 1 to describe the runway landing surface grip at airports affected by winter weather.
An FAA rulemaking committee convened after a Boeing 737 runway overrun in December 2005 at Chicago’s Midway International Airport “to review related FAA regulations, policies, and industry practices in an effort to develop mitigation strategies designed to reduce/eliminate these occurrences.”
Duke said the report is not rulemaking, so operator compliance is voluntary, but it “impacts every pilot as it changes the way runway condition and braking action are reported.”
With the new procedures, some of the condition-reporting language has changed and other definitions are clarified. The goal was to give pilots and operators a clearer picture of a runway’s grip during winter operations when snow, sleet, and ice affect performance and braking.
The committee reported that “when available, ATC furnishes pilots the quality of braking action received from pilots or airport management. The quality of braking action is described by the terms ‘good,’ ‘good to medium,’ ‘medium,’ ‘medium to poor,’ ‘poor,’ and ‘nil,’ or a combination of these terms. When pilots report the quality of braking action by using the terms noted above, they should use descriptive terms that are easily understood, such as, ‘braking action poor the first/last half of the runway,’ together with the particular type of aircraft.”
The challenges for general aviation pilots will be to learn the new braking action terms and interpret how runway condition codes can be used to better assess runway contamination. The word “contamination” in this case relates to how slippery a runway may be due to wintry precipitation that has accumulated. The surface friction affects takeoff, landing, and no-go decisions. The Aeronautical Information Manual and FAA guidance is in the process of being updated to reflect the changes.
Duke said most GA aircraft manufacturers will make information available so pilots can interpret the information and how that will impact an aircraft’s stopping distance.
Airport operators also will need to familiarize themselves with the FAA’s new winter advisory circular and the associated notice to airmen procedures for reporting a runway’s grip condition, known as a field condition report.
For airports where Mu friction reports are not used, the FAA’s new procedures call for “numerical readings that range between ‘0’ (the worst) and ’6’ (the best) that indicate runway contamination. These values must be included on the ATIS broadcast when the reportable condition is 5 or less in any of the three runway zones (touchdown, midpoint, rollout).”
Duke said that the core of the performance assessment is the concept of operators using the new Runway Condition Assessment Matrix guidelines to determine runway condition and for pilots to interpret the situation in a standardized format based on airplane performance data supplied by manufacturers.
The concept attempts to replace subjective judgments of runway conditions with objective assessments that are tied directly to contaminant type and depth categories, which have been determined by airplane manufacturers to cause specific changes in an airplane’s braking performance.
Cessna Aircraft Co., a subsidiary of Textron Aviation, has actively participated in the Takeoff and Landing Performance Assessment rulemaking committee and believes the recommendations equip pilots of all aircraft types to make better-informed decisions regarding the ability to safely takeoff or land. The flight crew version of the Runway Condition Assessment Matrix is published in FAA Advisory Circular 91-79 and is available on the FAA website.
Duke said AOPA has participated in the committee’s briefings and is helping get the word out to members. “The hope is that the changes in wintertime runway surface reporting will help reduce runway excursions and provide better runway condition reports to pilots.”
