Professional Pilot, October 2016
condition codes of the Runway Condition Assessment Matrix RCAM As of Oct 1 2016 braking action quality is being described by the terms good good to medium medium medium to poor poor and nil Previously no correlation had been established between runway friction values Mu and the old descriptive terms good fair poor and nil One of the benefits of RCAM is that these terms are now common among the airport authoritys assessment pilot reports and descriptions in NOTAM Airport management will report runway conditions anytime the runway centerline is contaminated along a distance of 500 ft or more and following snow clearing anti icing deicing or sanding the runway Additionally runway conditions will be measured anytime there is an aircraft incident or accident Measurements will be made approximately 10 to 20 ft from the centerline in the direction of landing traffic and will obtain 3 tests in each runway zone touchdown midpoint and rollout or if using continuous friction measuring equipment for the full length of the runway Runway condition reports will be updated anytime runway surface conditions change and when plowing sweeping applying chemicals or whenever traffic flow changes Note that a runway condition assessment of nil braking required closure of that surface except for emergencies The 3 terms defined by FAA for RCAM are 1 Dry runway Not wet or contaminated If only 25 or less of the 72 PROFESSIONAL PILOT October 2016 runway surface area is covered by visible moisture frost slush or snow the runway is considered dry 2 Wet runway More than 25 of the runway area is covered by visible dampness no deeper than 1 8th inch 3 Contaminated runway More than 25 of the runway area is cover by frost ice or any depth of snow slush or water deeper than 1 8th inch Runway condition codes derived from testing will be reported in groups of 3 such as 5 4 4 correlating to each runway segment touchdown midpoint and rollout Codes align with ICAO Annex 14 and provide standard shorthand to assess the condition of each third of the runway The criteria pilots should use when reporting braking actions are 1 Good Braking deceleration is normal for the wheel breaking effort applied and directional control is normal 2 Good to medium Braking deceleration or directional control is between good and medium fair braking action 3 Medium fair Braking deceleration is noticeably reduced for the wheel braking effort applied or directional control is noticeable reduced 4 Medium fair to poor Braking deceleration or directional control is between medium and poor Obviously the pilots perception of conditions varies However 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 is poor in the first last half of the runway and include their type of aircraft When tower controllers have received runway braking action reports containing the terms medium medium to poor poor or nil or whenever weather conditions are conducive to deteriorating or rapidly changing runway braking conditions the tower will include on ATIS broadcast the statement Braking Action Advisories are in Effect If the RCAM assessment does not match a landing aircrafts assessment airport management must then decide to downgrade reported runway conditions or conduct a following assessment with ground equipment Only under limited conditions may the airport report a higher code The follow 4 conditions must be met if the airport authority intends to raise a code 1 All observations judgement and vehicle braking actions support a higher code 2 Mu values in the range of codes 4 to 6 are obtained Mu 40 or higher 3 Codes no higher than 3 may be applied to a runway previously reported as 0 or 1 4 Monitor the runway as long as this higher code is in effect If sanding or other mitigation methods are used the airport management must confirm the effectiveness of the treatment A completely new assessment made when conditions warrant will effectively reset the runway condition code decision process Conclusion New safety tools such as TALPA and RCAM are only as good as the ability of management air traffic and flightcrews to understand and apply the tools correctly No assessment process will ever completely mitigate arrival or departure runway conditions beyond what the flightcrew is prepared for Having methods to equalize the understanding among the parties involved is nonetheless an improvement over past methods Typical towed runway friction assessment unit in action after rain water contaminated the tarmac Bill Gunn is the compliance manager for the State of Texas Aviation Division He lectures nationally for a private aviation advocacy group and flies for work and pleasure
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