[{"data":1,"prerenderedAt":313},["ShallowReactive",2],{"learn-\u002Flearn\u002Fturbulence-reporting-and-intensity":3,"learn-nav-\u002Flearn\u002Fturbulence-reporting-and-intensity":276},{"id":4,"title":5,"body":6,"date":211,"description":212,"draft":213,"extension":214,"faqs":215,"howTo":225,"keyTakeaways":226,"meta":231,"navigation":232,"path":233,"quiz":234,"seo":261,"series":262,"seriesOrder":263,"sources":264,"stem":273,"topic":274,"__hash__":275},"learn\u002Flearn\u002Fturbulence-reporting-and-intensity.md","Turbulence reporting and intensity scales",{"type":7,"value":8,"toc":201},"minimark",[9,13,19,24,38,42,58,86,99,103,110,130,133,137,140,161,165,185,189],[10,11,12],"p",{},"\"It was a bit bumpy\" tells the crew behind you almost nothing. A turbulence report only helps if everyone means the same thing by each word, so aviation defines the intensities by what the aircraft actually does, and pairs them with how often the bumps come. Learn the scale and your reports become useful, and other pilots' reports become readable.",[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},"why-it-is-judged-by-the-aircraft-not-the-feel","Why it is judged by the aircraft, not the feel",[10,25,26,27,31,32,37],{},"The same patch of air feels very different in a light trainer and a heavy jet, so turbulence is graded by the ",[28,29,30],"strong",{},"aircraft's reaction and the effect on the occupants"," rather than by a subjective sense of roughness. That is what makes a ",[33,34,36],"a",{"href":35},"\u002Flearn\u002Fhow-to-read-a-pirep","pilot report"," comparable: when a crew calls moderate turbulence, they are describing a defined effect, not a mood.",[20,39,41],{"id":40},"the-intensity-scale","The intensity scale",[10,43,44,45,51,52,57],{},"The ",[33,46,50],{"href":47,"rel":48},"https:\u002F\u002Fwww.faa.gov\u002Fair_traffic\u002Fpublications\u002Fatpubs\u002Faim_html\u002Fchap7_section_1.html",[49],"nofollow","FAA Aeronautical Information Manual"," sets out four intensities, and ",[33,53,56],{"href":54,"rel":55},"https:\u002F\u002Fskybrary.aero\u002Farticles\u002Fturbulence",[49],"SKYbrary"," summarises them the same way:",[59,60,61,68,74,80],"ul",{},[62,63,64,67],"li",{},[28,65,66],{},"Light",": slight, momentary changes in attitude, or a slight, rhythmic bumpiness; occupants feel a slight strain against the seatbelt and unsecured objects stay put.",[62,69,70,73],{},[28,71,72],{},"Moderate",": more pronounced changes in attitude and altitude, but the aircraft stays in control at all times; occupants feel a definite strain against the belt and loose objects move about.",[62,75,76,79],{},[28,77,78],{},"Severe",": large, abrupt changes in attitude and altitude, with the aircraft momentarily out of control; occupants are forced violently against the belt and loose objects are tossed about.",[62,81,82,85],{},[28,83,84],{},"Extreme",": the aircraft is tossed about so violently that it is practically impossible to control and may suffer structural damage.",[10,87,88,89,92,93,98],{},"The FAA also uses ",[28,90,91],{},"chop",", light or moderate, for a rhythmic, rapid bumpiness without the larger excursions of altitude. ",[33,94,97],{"href":95,"rel":96},"https:\u002F\u002Fstore.icao.int\u002Fen\u002Fannex-3-meteorological-service-for-international-air-navigation-1",[49],"ICAO Annex 3"," air-reports use light, moderate and severe.",[20,100,102],{"id":101},"how-often-the-frequency-words","How often: the frequency words",[10,104,105,106,109],{},"Intensity is only half the message. The report pairs it with ",[28,107,108],{},"how often"," the turbulence occurs:",[59,111,112,118,124],{},[62,113,114,117],{},[28,115,116],{},"Occasional",": less than one third of the time;",[62,119,120,123],{},[28,121,122],{},"Intermittent",": between one third and two thirds of the time;",[62,125,126,129],{},[28,127,128],{},"Continuous",": more than two thirds of the time.",[10,131,132],{},"So \"occasional moderate\" and \"continuous moderate\" are the same strength but a very different ride.",[20,134,136],{"id":135},"a-worked-example","A worked example",[10,138,139],{},"Cruising at FL080 near a line of building cumulus, you hit bumps that repeatedly throw the aircraft enough to need a firm correction, you feel a definite strain against the belt, and your kneeboard slides off the seat, but you keep full control throughout. The bumps come and go, present perhaps half the time over a five-minute stretch.",[10,141,142,143,146,147,150,151,154,155,160],{},"That is ",[28,144,145],{},"moderate"," turbulence (full control retained, but pronounced changes and loose items moving) at an ",[28,148,149],{},"intermittent"," frequency (a third to two thirds of the time). The report to pass, alongside your position, altitude, time and aircraft type, is \"intermittent moderate turbulence, FL080.\" A controller can relay that to following aircraft and to the ",[33,152,153],{"href":35},"air-report"," system defined in ",[33,156,159],{"href":157,"rel":158},"https:\u002F\u002Fstore.icao.int\u002Fen\u002Fprocedures-for-air-navigation-services-air-traffic-management-doc-4444",[49],"ICAO Doc 4444",", and the next crew can decide whether to request a different level.",[20,162,164],{"id":163},"common-pitfalls","Common pitfalls",[59,166,167,173,179],{},[62,168,169,172],{},[28,170,171],{},"Do not inflate it."," Calling moderate turbulence severe sends others on needless reroutes and dilutes the word when it is genuinely needed.",[62,174,175,178],{},[28,176,177],{},"Frequency is not intensity."," Continuous light is not worse than occasional severe; report both so the meaning is clear.",[62,180,181,184],{},[28,182,183],{},"Aircraft type matters to the reader."," A report from a light aircraft and one from an airliner in the same air may differ, so the type is part of the message.",[20,186,188],{"id":187},"in-pilot-efb","In Pilot EFB",[10,190,191,192,195,196,200],{},"Pilot EFB keeps the ",[33,193,194],{"href":35},"pilot reports"," and the ",[33,197,199],{"href":198},"\u002Flearn\u002Fhow-to-read-a-sigmet-and-airmet","SIGMETs and AIRMETs"," you have pulled in one place, so you can see where turbulence has already been reported along your route and brief for it before you set off. A briefing you have already pulled stays readable with no signal; fetching fresh reports needs a connection. Pilot EFB is not a certified Electronic Flight Bag, so treat it as a study and planning aid and brief from your official source of record.",{"title":202,"searchDepth":203,"depth":203,"links":204},"",2,[205,206,207,208,209,210],{"id":22,"depth":203,"text":23},{"id":40,"depth":203,"text":41},{"id":101,"depth":203,"text":102},{"id":135,"depth":203,"text":136},{"id":163,"depth":203,"text":164},{"id":187,"depth":203,"text":188},"2026-06-22","What light, moderate, severe and extreme turbulence actually mean, how the intensity is judged by the aircraft's reaction rather than a guess, and how pilots report it so the aircraft behind benefits.",false,"md",[216,219,222],{"q":217,"a":218},"How is turbulence intensity classified?","By the aircraft's reaction, not by feel alone. The standard scale runs light, moderate, severe and extreme. Light causes slight, momentary changes in attitude or a slight strain against the seatbelt; moderate is more pronounced but the aircraft stays in control and unsecured items move; severe causes large, abrupt changes in attitude and altitude with the aircraft momentarily out of control and occupants forced violently against the belt; extreme tosses the aircraft about so violently that it is practically impossible to control and may cause structural damage.",{"q":220,"a":221},"What do occasional, intermittent and continuous mean in a turbulence report?","They describe how often the bumps occur, not how strong they are. Occasional means less than one third of the time, intermittent means between one third and two thirds, and continuous means more than two thirds of the time. Pairing a frequency with an intensity, for example occasional moderate, tells the next crew both how hard and how often.",{"q":223,"a":224},"Do all authorities use the same turbulence scale?","The light, moderate and severe categories are common ground. The FAA also uses extreme and the term chop for rhythmic bumpiness, as in light chop or moderate chop, in its Aeronautical Information Manual. ICAO air-reports under Annex 3 use light, moderate and severe. When you read a report, note which system it follows, but the practical meaning of each step is broadly the same.",null,[227,228,229,230],"Turbulence intensity is judged by the aircraft's reaction and the effect on occupants, not by feel, so reports are comparable between aircraft.","The scale runs light, moderate, severe and extreme, each step a sharper change in attitude, altitude and control.","Occasional, intermittent and continuous describe how often, not how strong: under a third, a third to two thirds, and over two thirds of the time.","FAA reports add extreme and chop; ICAO air-reports use light, moderate and severe, but the meaning of each step is broadly the same.",{},true,"\u002Flearn\u002Fturbulence-reporting-and-intensity",[235,244,253],{"q":236,"options":237,"answer":242,"explanation":243},"On what is turbulence intensity primarily judged?",[238,239,240,241],"The colour of the sky","The aircraft's reaction and the effect on occupants","The outside air temperature","The time of day",1,"Intensity is classified by the aircraft's reaction and the effect on occupants, not by feel alone, which is what makes a report comparable between aircraft.",{"q":245,"options":246,"answer":251,"explanation":252},"In a turbulence report, what does occasional mean?",[247,248,249,250],"Less than one third of the time","Exactly half the time","More than two thirds of the time","Once per flight",0,"Occasional means the turbulence occurs less than one third of the time; intermittent is one third to two thirds, and continuous is more than two thirds.",{"q":254,"options":255,"answer":242,"explanation":260},"How is severe turbulence described?",[256,257,258,259],"A slight, momentary strain against the seatbelt","Large, abrupt changes in attitude and altitude with the aircraft momentarily out of control","No effect on the aircraft at all","Only a change in airspeed indication","Severe turbulence causes large, abrupt changes in attitude and altitude, the aircraft momentarily out of control, and occupants forced violently against the belt; extreme is worse still and may cause structural damage.",{"title":5,"description":212},"decode-the-weather",7,[265,267,269,271],{"label":266,"url":47},"FAA Aeronautical Information Manual, Chapter 7 Section 1 (Meteorology)",{"label":268,"url":95},"ICAO Annex 3: Meteorological Service for International Air Navigation",{"label":270,"url":157},"ICAO Doc 4444: PANS-ATM",{"label":272,"url":54},"SKYbrary: Turbulence","learn\u002Fturbulence-reporting-and-intensity","Weather","L_3VA2Gzla2-h-jpSyPUydhYC91O0lnU6hNSfGV-d4k",{"related":277,"newer":292,"older":297,"series":301},[278,283,288],{"path":279,"title":280,"description":281,"date":211,"topic":274,"draft":213,"minutes":282,"series":225,"seriesOrder":225},"\u002Flearn\u002Fcloud-types-explained","Cloud types and what they tell a pilot","The ten cloud genera grouped into high, middle and low, the difference between heaped and layered cloud, and how to read what each type is telling you about stability, moisture and the weather ahead.",3,{"path":284,"title":285,"description":286,"date":211,"topic":274,"draft":213,"minutes":287,"series":225,"seriesOrder":225},"\u002Flearn\u002Fjet-stream-and-clear-air-turbulence","The jet stream and clear-air turbulence","What a jet stream is, where it sits near the tropopause, and why the wind shear around it produces clear-air turbulence that arrives with no cloud to warn you.",4,{"path":289,"title":290,"description":291,"date":211,"topic":274,"draft":213,"minutes":287,"series":225,"seriesOrder":225},"\u002Flearn\u002Fmountain-waves-and-rotor","Mountain waves and rotor","How stable air flowing over high ground sets up standing mountain waves and the violent rotor beneath them, the cloud signs that give them away, and why the turbulence and downdraughts deserve respect.",{"path":293,"title":294,"description":295,"date":211,"topic":296,"draft":213,"minutes":287,"series":225,"seriesOrder":225},"\u002Flearn\u002Ftransition-altitude-and-transition-level","Transition altitude and transition level","Where altitudes give way to flight levels, why pilots swap between the local QNH and the standard 1013 pressure setting, and the simple rule for when to change the altimeter climbing and descending.","Operations",{"path":298,"title":299,"description":300,"date":211,"topic":296,"draft":213,"minutes":287,"series":225,"seriesOrder":225},"\u002Flearn\u002Fv-speeds-explained","V-speeds explained","What the V in V-speeds means, the difference between a design limit and an operating speed, and a plain-language tour of the speeds a pilot lives by, from the stall and the airspeed indicator's colour code to V1, Vr, V2, Vref and Vne.",{"slug":262,"title":302,"part":263,"total":303,"prev":304,"next":309},"Decode the weather",8,{"path":305,"title":306,"description":307,"date":211,"topic":274,"draft":213,"minutes":287,"series":262,"seriesOrder":308},"\u002Flearn\u002Ftaf-change-groups","TAF change groups: TEMPO, BECMG, PROB and FM","A deeper look at the change groups that make a TAF a forecast rather than a snapshot, with the exact meaning of FM, BECMG, TEMPO and PROB and a worked example that decodes them in order.",6,{"path":310,"title":311,"description":312,"date":211,"topic":274,"draft":213,"minutes":287,"series":262,"seriesOrder":303},"\u002Flearn\u002Fvolcanic-ash-and-sigmet","Volcanic ash and the SIGMET","Why volcanic ash is so dangerous to aircraft, how Volcanic Ash Advisory Centres and SIGMETs warn you about it, and why an ash SIGMET runs longer and is issued further ahead than an ordinary one.",1782089964075]