[{"data":1,"prerenderedAt":401},["ShallowReactive",2],{"learn-\u002Flearn\u002Fthe-global-reporting-format-for-runway-conditions":3,"learn-nav-\u002Flearn\u002Fthe-global-reporting-format-for-runway-conditions":386},{"id":4,"title":5,"body":6,"date":314,"description":315,"draft":316,"extension":317,"faqs":318,"howTo":328,"keyTakeaways":336,"meta":341,"navigation":342,"path":343,"quiz":344,"seo":370,"series":371,"seriesOrder":371,"sources":372,"stem":383,"topic":384,"__hash__":385},"learn\u002Flearn\u002Fthe-global-reporting-format-for-runway-conditions.md","The Global Reporting Format for runway conditions",{"type":7,"value":8,"toc":303},"minimark",[9,13,19,24,69,72,76,98,137,140,144,168,171,175,190,193,207,221,225,232,235,265,268,272,292,296],[10,11,12],"p",{},"When a runway is wet, slushy or snow-covered, the question a pilot needs answered is simple: how much braking and directional control can I count on? The Global Reporting Format is the worldwide answer to that question, written in one language every controller, dispatcher and pilot can read the same way.",[14,15,16],"blockquote",{},[10,17,18],{},"This is general educational information, not operational, legal, or regulatory advice. Rules differ by authority and change over time. Always verify against current official sources and follow your operator's approved procedures.",[20,21,23],"h2",{"id":22},"one-format-worldwide","One format, worldwide",[10,25,26,27,39,40,43,44,50,51,56,57,62,63,68],{},"The ",[28,29,30,31,38],"strong",{},"Global Reporting Format (",[32,33,37],"a",{"href":34,"className":35},"\u002Flearn\u002Fglossary#gt-grf",[36],"glossary-link","GRF",")"," is the harmonised method for assessing and reporting the surface condition of a runway, applicable worldwide since ",[28,41,42],{},"4 November 2021",". It is set out in ",[32,45,49],{"href":46,"rel":47},"https:\u002F\u002Fstore.icao.int\u002Fen\u002Fprocedures-for-air-navigation-services-pans-aerodromes-doc-9981",[48],"nofollow","ICAO Doc 9981 (PANS-Aerodromes)"," and ",[32,52,55],{"href":53,"rel":54},"https:\u002F\u002Fstore.icao.int\u002Fen\u002Fannex-14-aerodromes",[48],"Annex 14",", and the same scheme is used in the United States as the ",[32,58,61],{"href":59,"rel":60},"https:\u002F\u002Fwww.faa.gov\u002Fsites\u002Ffaa.gov\u002Ffiles\u002Fother_visit\u002Faviation_industry\u002Fairline_operators\u002Fairline_safety\u002FSAFO16009.pdf",[48],"FAA's RCAM"," and in the United Kingdom under ",[32,64,67],{"href":65,"rel":66},"https:\u002F\u002Fwww.caa.co.uk\u002Fpublication\u002Fdownload\u002F19138",[48],"CAA guidance",".",[10,70,71],{},"Before the GRF, runway-state reporting was a patchwork of friction readings and local braking descriptions that did not always transfer cleanly between countries or correlate well with how an aircraft actually stopped. The GRF replaced that with a single chain: assess the contaminant, read a code from a matrix, and report it in a fixed form that everyone decodes the same way.",[20,73,75],{"id":74},"the-runway-condition-code-6-to-0","The runway condition code: 6 to 0",[10,77,78,79,87,88,91,92,97],{},"At the heart of the format is the ",[28,80,81,82,38],{},"runway condition code (",[32,83,86],{"href":84,"className":85},"\u002Flearn\u002Fglossary#gt-rwycc",[36],"RWYCC",", a single digit from ",[28,89,90],{},"6 down to 0",". Each value carries a plain braking-action word, as ",[32,93,96],{"href":94,"rel":95},"https:\u002F\u002Fskybrary.aero\u002Farticles\u002Fglobal-reporting-format-grf",[48],"SKYbrary"," and the source documents set out:",[99,100,101,107,112,117,122,127,132],"ul",{},[102,103,104],"li",{},[28,105,106],{},"6: dry.",[102,108,109],{},[28,110,111],{},"5: good.",[102,113,114],{},[28,115,116],{},"4: good to medium.",[102,118,119],{},[28,120,121],{},"3: medium.",[102,123,124],{},[28,125,126],{},"2: medium to poor.",[102,128,129],{},[28,130,131],{},"1: poor.",[102,133,134],{},[28,135,136],{},"0: less than poor.",[10,138,139],{},"A higher number is a better surface. A 6 is reported for a dry runway; the lower the number, the less braking and directional control the surface offers.",[20,141,143],{"id":142},"the-assessment-matrix-rcam","The assessment matrix (RCAM)",[10,145,146,147,155,156,159,160,163,164,167],{},"The code does not come from a friction reading. It comes from the ",[28,148,149,150,38],{},"Runway Condition Assessment Matrix (",[32,151,154],{"href":152,"className":153},"\u002Flearn\u002Fglossary#gt-rcam",[36],"RCAM",", a table that maps the ",[28,157,158],{},"type of contaminant"," (for example frost, wet, slush, dry snow, compacted snow or ice) and its ",[28,161,162],{},"depth"," to a starting condition code and the matching braking-action word. The assessor then checks that against other cues, including the outside air temperature and, importantly, ",[28,165,166],{},"pilot reports of braking action",": a special air-report of braking worse than the matrix implies can downgrade the code.",[10,169,170],{},"This is the key idea of the GRF. The aerodrome describes what is physically on the runway, the matrix turns that into a code, and the code is the same currency the flight crew use to look up their aircraft's performance.",[20,172,174],{"id":173},"how-the-report-is-built","How the report is built",[10,176,177,178,181,182,185,186,189],{},"A GRF report describes the runway in ",[28,179,180],{},"three equal-length thirds",", and gives, for each third, its ",[28,183,184],{},"condition code, the contaminant type, the depth in millimetres, and the percentage of that third the contaminant covers",". The thirds are always listed ",[28,187,188],{},"in the direction of the lower runway designator number",", so a report for runway 09\u002F27 is read in the 09 direction whichever end you are landing on.",[10,191,192],{},"The full report has two parts:",[99,194,195,201],{},[102,196,26,197,200],{},[28,198,199],{},"aeroplane performance"," section: the per-third codes, contaminant, depth and coverage, plus any reduced declared distance. This is the part that feeds landing and take-off performance.",[102,202,26,203,206],{},[28,204,205],{},"situational awareness"," section: plain-language detail such as drifting snow, snow banks, a reduced runway width, or the state of taxiways and aprons.",[10,208,209,210,214,215,220],{},"The report is distributed in the ",[32,211,213],{"href":212},"\u002Flearn\u002Fnotam-categories-and-time-windows","SNOWTAM"," format and can also be passed by ",[32,216,219],{"href":217,"className":218},"\u002Flearn\u002Fglossary#gt-atis",[36],"ATIS"," or by voice, so the same coded assessment reaches you whether you are reading a briefing pack or listening on the radio.",[20,222,224],{"id":223},"a-worked-example","A worked example",[10,226,227,228,231],{},"Suppose a report gives runway 09 the codes ",[28,229,230],{},"5\u002F5\u002F3",", with the first two thirds wet and the final third covered by 5 mm of wet snow over half its area.",[10,233,234],{},"Reading it through:",[99,236,237,244,256,259],{},[102,238,239,240,243],{},"The thirds are listed in the ",[28,241,242],{},"09 direction",", so 5 is the first third you cross on landing on 09.",[102,245,246,248,249,252,253,68],{},[28,247,230],{}," means the first two thirds are ",[28,250,251],{},"good"," and the final third is ",[28,254,255],{},"medium",[102,257,258],{},"The final third is the one to plan around: 5 mm of wet snow over 50 per cent of it has pulled that third down to a 3.",[102,260,261,262,264],{},"Land on runway 27 instead and you meet the thirds in reverse, so the ",[28,263,255],{}," third is now first, near the touchdown zone.",[10,266,267],{},"The figures are awareness. The stopping numbers come from your aircraft's approved performance data for that contaminant and code.",[20,269,271],{"id":270},"common-pitfalls","Common pitfalls",[99,273,274,280,286],{},[102,275,276,279],{},[28,277,278],{},"The codes are read in a fixed direction."," They follow the lower runway designator, not your landing direction, so on the reciprocal runway the order is reversed.",[102,281,282,285],{},[28,283,284],{},"A good first third is not a good runway."," The worst third is usually what matters most, and where it sits relative to your touchdown and stop changes with the runway in use.",[102,287,288,291],{},[28,289,290],{},"The code is a starting point, not a stopping distance."," Pair it with your aircraft's contaminated-runway performance data, and treat a worse pilot braking-action report as the more current picture.",[20,293,295],{"id":294},"in-pilot-efb","In Pilot EFB",[10,297,298,299,302],{},"Pilot EFB brings the ",[28,300,301],{},"NOTAMs for your aerodrome",", including runway-state notices, into the briefing, shown as the raw text alongside a decoded view so a runway-condition report is in front of you rather than buried. A briefing you have already pulled stays readable offline; fetching the latest runway state needs a connection. Pilot EFB is offline-first and is not a certified Electronic Flight Bag, so confirm the current report and apply your aircraft's approved performance data before you commit to a runway.",{"title":304,"searchDepth":305,"depth":305,"links":306},"",2,[307,308,309,310,311,312,313],{"id":22,"depth":305,"text":23},{"id":74,"depth":305,"text":75},{"id":142,"depth":305,"text":143},{"id":173,"depth":305,"text":174},{"id":223,"depth":305,"text":224},{"id":270,"depth":305,"text":271},{"id":294,"depth":305,"text":295},"2026-06-21","How the Global Reporting Format (GRF) describes a contaminated runway, including the runway condition code (RWYCC) from 6 to 0, the assessment matrix (RCAM), and how the report is split into thirds.",false,"md",[319,322,325],{"q":320,"a":321},"What is the Global Reporting Format?","The Global Reporting Format, or GRF, is the worldwide method for assessing and reporting the condition of a runway surface, applicable since 4 November 2021. It replaced a patchwork of national friction and braking systems with one common language: a runway condition code from 6 down to 0, a matching braking-action word, and a description of the contaminant on each third of the runway.",{"q":323,"a":324},"What does the runway condition code (RWYCC) mean?","The runway condition code, or RWYCC, runs from 6 to 0. A 6 is a dry runway, 5 is good, 4 is good to medium, 3 is medium, 2 is medium to poor, 1 is poor, and 0 is less than poor. It is derived from the type and depth of any contaminant using the Runway Condition Assessment Matrix, and a code is given for each third of the runway.",{"q":326,"a":327},"How does the GRF report split the runway?","The runway is divided into three equal-length thirds, and a separate condition code, contaminant type, depth and coverage are reported for each. The thirds are always listed in the direction of the lower runway designator number, so the same report reads the same way regardless of which end you land on.",{"name":329,"steps":330},"Read a Global Reporting Format runway report",[331,332,333,334,335],"Identify the runway and read the three condition codes, listed in the direction of the lower runway designator number.","Read each third's contaminant type, depth in millimetres, and the percentage of that third it covers.","Translate each code to its braking-action word: 6 dry, 5 good, 4 good to medium, 3 medium, 2 medium to poor, 1 poor, 0 less than poor.","Read the situational-awareness section for extra detail such as drifting snow, reduced width or taxiway state.","Use the figures for awareness, then apply your aircraft's approved performance data for the actual contaminant and code.",[337,338,339,340],"The Global Reporting Format (GRF) is the worldwide runway-condition reporting method, applicable since 4 November 2021.","The runway condition code (RWYCC) runs from 6 (dry) through 5 good, 4 good to medium, 3 medium, 2 medium to poor, 1 poor, to 0 less than poor.","A separate code, contaminant type, depth and coverage are reported for each of the runway's three thirds, in the direction of the lower runway designator.","The Runway Condition Assessment Matrix (RCAM) maps the contaminant type and depth to the code and braking-action word.",{},true,"\u002Flearn\u002Fthe-global-reporting-format-for-runway-conditions",[345,354,362],{"q":346,"options":347,"answer":352,"explanation":353},"On the GRF scale, what does a runway condition code of 5 mean?",[348,349,350,351],"Dry","Good","Good to medium","Poor",1,"A code of 5 is good. 6 is dry, 4 is good to medium, and 0 is less than poor.",{"q":355,"options":356,"answer":352,"explanation":361},"How is a runway divided for a GRF report?",[357,358,359,360],"Into halves, reported from the centreline","Into three equal thirds, in the direction of the lower runway designator","Into the touchdown zone only","It is reported as a single average condition","The runway is split into three equal-length thirds, each with its own code, contaminant and depth, listed in the direction of the lower runway designator number.",{"q":363,"options":364,"answer":352,"explanation":369},"What determines a third's runway condition code?",[365,366,367,368],"The wind across the runway","The contaminant type and depth, read from the assessment matrix","The length of the runway","The time of day","The Runway Condition Assessment Matrix maps the type and depth of the contaminant to a condition code and braking-action word.",{"title":5,"description":315},null,[373,375,377,379,381],{"label":374,"url":46},"ICAO Doc 9981: PANS-Aerodromes",{"label":376,"url":53},"ICAO Annex 14: Aerodromes, Volume I",{"label":378,"url":59},"FAA SAFO 16009: Runway Condition Assessment Matrix (RCAM)",{"label":380,"url":65},"UK CAA CAP 2174: Global Reporting Format guidance",{"label":382,"url":94},"SKYbrary: Global Reporting Format (GRF)","learn\u002Fthe-global-reporting-format-for-runway-conditions","Operations","LS0KZy7fxdygj1s4sMAZWdwrI7geQyQSVXy9LASmBcY",{"related":387,"newer":393,"older":397,"series":371},[388,393,397],{"path":389,"title":390,"description":391,"date":314,"topic":384,"draft":316,"minutes":392,"series":371,"seriesOrder":371},"\u002Flearn\u002Fcold-temperature-altimeter-corrections","Cold-temperature altimeter corrections","Why a pressure altimeter over-reads in cold air, leaving you lower than indicated, and how to correct minimum altitudes for temperature on an approach in mountainous or freezing conditions.",4,{"path":394,"title":395,"description":396,"date":314,"topic":384,"draft":316,"minutes":392,"series":371,"seriesOrder":371},"\u002Flearn\u002Fmode-s-and-ads-b-explained","Mode S and ADS-B explained","How Mode S adds a 24-bit address, selective interrogation and a data link to the transponder, the difference between elementary and enhanced surveillance, and how ADS-B broadcasts your GPS position.",{"path":398,"title":399,"description":400,"date":314,"topic":384,"draft":316,"minutes":392,"series":371,"seriesOrder":371},"\u002Flearn\u002Ftop-of-descent-and-the-3-to-1-rule","Top of descent and the 3:1 rule","How to work out your top of descent with the 3:1 rule, the 60-to-1 relationship behind it, and the rate of descent that holds a roughly 3 degree path, with a worked example.",1781989191483]