Meteorology

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Meteorology

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12-MAY-2011 Table of Contents

General Information

2

Meteorological Documentation Support

Flight Documentation

and

1.1

General

10

1.2

Aviation Weather Services

10

1.2.1

General

10

1.2.2

Data

10

1.3

Observation and Reports

10

1.4

Meteorological Offices

10

1.5

Weather Assistance by ATC

10

1.6

Ground Weather Radar

20

1.7

Windshear and Turbulence Warning System

20

2.1

General

20

2.2

Standard Flight Documentation

20

2.3

Reduced Flight Documentation

30

2.4

Contents of Flight Documentation

30

2.4.1

Significant Weather Chart (SIGWX)

30

2.4.2

Upper Wind and Temperature Chart

80

2.4.3

ICAO Codes - TAF & METAR

90

2.4.3.1

90

2.4.3.2

Operational Meteorological Information (OPMET) Data Bank Interrogation Designator Delayed/Corrected OPMET

2.4.3.3

Aerodrome Forecast - TAF

2.4.3.4

Aerodrome Report - METAR / SPECI

110

2.4.3.5

Aerodrome Trend Forecasts

120

2.4.3.6

Additional Information to ICAO Codes

120

2.5

SIGMET / AIRMET

130

2.5.1

SIGMET General

130

2.5.2

AIRMET General

130

2.5.3

SIGMET / AIRMET - ICAO Code Content

130

2.5.4

Tropical Cyclone SIGMET - TC

130

2.5.5

Volcanic Ash SIGMET - VA

130

2.5.6

SIGMET / AIRMET U.S. System

140

2.6

Aerodrome Warnings

140

2.6.1

Aerodrome Warnings - AD Warning

140

2.6.2

Wind Shear Warnings - WS WRNG

140

90 90

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II 3

4

5

Aircraft Observations and Reports

Volcanic Activity Ashreports

Potential Flight Hazards

/

3.1

General

140

3.2

Air to Ground Datalink

140

3.3

ATIS / VOLMET

140

3.3.1

ATIS (Automated Terminal Information Service)

140

3.3.2

VOLMET (Meteorological Information for Aircraft in-Flight)

150

4.1

Reporting Of Aircraft Observations During Flight

150

4.2

Routine Aircraft Observations

150

4.3

Special and Other Non-Routine Aircraft Observations

160

5.1

General

160

5.2

ASHTAM

170

6.1

General

170

6.2

Turbulence

170

6.2.1

Turbulence Grade Classification

170

6.2.2

Clear Air Turbulence (CAT) Encounter

180

6.2.2.1

General

180

6.2.2.2

Clear Air Turbulence Phenomenon

180

6.2.2.3

Forecast Presentation

180

6.2.2.4

Convective Induces Turbulences

180

6.2.2.5

Topographically induced Turbulence

180

6.2.2.6

Wake Turbulence

180

6.3

Precipitation, Icing

180

6.3.1

General

180

6.3.2

Categories of Precipitation

180

6.3.3

Classification of Precipitation Intensity

180

6.3.4

Airframe Categories of Icing

190

6.4

Special Winter Phenomena

190

6.4.1

Thunderstorms, CB / TCU

190

6.4.2

Downdraft and Microburst (MB)

190

6.4.2.1

Microburst on final

200

6.4.2.2

Microburst after Take-Off

200

6.4.3

Mountain Waves (MTW)

210

6.4.4

Wind Shears

210

6.4.5

Inversion

210

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In-Flight Information

Meteorology

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Winter Operation

Decoding Meteorological Data

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7.1

Fluids and Procedures

210

7.1.1

De-/Anti-Icing Instructions

210

7.1.2

De-Icing and Anti-Icing Procedures

210

7.1.2.1

De-Icing / Anti-Icing Checks

220

7.1.2.2

Communication Procedure

230

7.1.3

Types of Fluids

240

7.1.3.1

General

240

7.1.3.2

Type I Fluids

250

7.1.3.3

Type II Fluids

250

7.2

Hold-Over-Time (HOT) Policy

250

7.2.1

General

250

7.2.1.1

Lowest Operational Use Temperature (LOUT):

260

7.2.2

One-Step- / Two-Step Guidelines

260

7.2.2.1

Type I Fluid

260

7.2.2.2

Type II, III and IV Fluids

260

7.2.3

HOT Active Frost Type I, II, III, and IV Fluids

270

7.2.4

Various Weather Conditions Type I Fluid

280

7.2.5

Various Weather Conditions Type II Fluid

290

7.2.6

Various Weather Conditions Type III fluid

300

7.2.7

Various Weather Conditions Type IV fluid

310

7.3

Adverse Runway Condition

320

7.3.1

Dissemination of RWY State Information

320

7.3.2

SNOWTAM

320

7.3.2.1

Issue/Validity of SNOWTAMs

320

7.3.3

METAR Runway Report

320

7.3.4

Issue/Validity of RWY Reports.

320

7.3.4.1

Assessment of Deposit

320

7.3.4.2

Measuring Devices

330

7.3.4.3

340

7.3.4.4

Relationship Between Friction Coefficient (FC) and Braking Action (BA) Differences from ICAO Standard

8.1

TAF & METAR Decoding (ICAO)

340

8.1.1

Runway Report Decoding

370

8.2

Military (NATO) Color Coded Weather Conditions

380

8.3

390

8.4

SIGMET / AIRMET - (OPMET Data Bank Designator) ASHTAM Decoding

8.5

SNOWTAM Decoding

400

340

390

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Meteorology

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14-OCT-2010 1 Meteorological Documentation and Support 1.1 General

This chapter describes ground and high altitude atmospheric conditions and weather phenomena. It covers mainly the decoding of weather reports (To clarify the content of the text, examples are added).

1.2 Aviation Weather Services 1.2.1 General c During aerodrome hours, the meteorological office is providing all necessary information for flight operations. At some aerodromes airline operators and crew members can retrieve required documents using an remote briefing location. Weather briefings may be provided via video conferencing facilities or telephone to flight crew members prior to departure. Exceptions are stated in the “Regional Supplementary Information” (RSIs) and “Country Rules and Regulations” (CRARs) of the Lido/RouteManual. 1.2.2 Data Aviation weather services consist of data acquisition, forecast production, and information dissemination; the latter is encompassing pre and in-flight requirements for cockpit crew and dispatch personnel.

1.3 Observation and Reports Meteorological stations are established at aerodromes or other significant points for air-navigation and are manned by humans or electronic measuring equipment. The observation forms the basis for the preparation of forecast and actual weather reports. These reports are coded in accordance with the International Civil Aviation Organization (ICAO) or the World Meteorological Organization (WMO) and distributed worldwide.

1.4 Meteorological Offices Meteorological offices are providing briefing, consulting, and flight documentation to flight crew or other flight operations personnel. They forward relevant information to air traffic control centers to communicate reports of hazardous weather to flights.

1.5 Weather Assistance by ATC Meteorological information of interest to pilots in-flight should be supplied by Air Traffic Service (ATS) and normally consist of the following: • non-routine and special reports • SIGMET and AIRMET Air Traffic Control (ATC) will issue information on significant weather and assist pilots in avoiding weather areas during all phases of flight. For safety reasons, an IFR flight must normally not deviate for meteorological reasons from an assigned course or altitude without a proper ATC clearance. ⇒

Navigation General Information

2.4 Weather Deviation Procedure

For departing aircraft: ATC transmits weather information regarding significant changes (surface wind direction/speed; VIS/RVR; Thunderstorms/Cumulonimbus; moderate/severe turbulence/icing; severe squall Sheet 384886

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Pilot’s requests to ATS for transmission of weather reports may be done for aerodromes with no Automatic Terminal Information Service (ATIS/D-ATIS) or not covered by meteorological broadcast (VHF VOLMET/DVOLMET).

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line/mountain waves; freezing precipitation; sand/dust storm; blowing snow; tornado; waterspout) except when it is known that aircraft has already received the information. (ATIS).

1.6 Ground Weather Radar Typically presents a display of precipitation within 150NM of the facility site; storms of considerable heights and intensity can be seen at greater ranges.

1.7 Windshear and Turbulence Warning System The Windshear and Turbulence Warning System (WTWS) will provide pilots in real-time windshear and turbulence alerts from 3NM on final approach to 3NM on departure. These warnings will be verbally relayed by ATC from information on alphanumeric alert display (AAD). Example of WTWS: 07LA WSA 15K+ 3MF means: RWY 07L Arrival Windshear Alert 15KT gain at 3 miles final or 07RD MBA 35K- 2MD means: RWY 07R Departure Microburst Alert 35KT loss at 2 miles. General warnings and TREND forecast will be broadcasted on ATIS/D-ATIS. Example of ATIS Arrival Information: 0920 07L 120/15G22 7000 RA BRK18 QNH 1012 Warning windshear on final.

2 Flight Documentation 2.1 General Documentation is required for each flight. The documentation must cover the flight in respect of time, altitude and geographical extent including the route between destination and destination alternate. Presentation may vary according to regional agreements and standards. Flight documentation must be supplied (or updated in case of delay) as close to departure as practicable.

2.2 Standard Flight Documentation Containing: • Significant Weather Chart (SIGWX) -

including wind forces (jet streams) and tropopause heights.

• Upper winds and temperature charts -

Aerodrome forecasts, actual and special report (For example: RWY report)

-

for aerodrome of departure, take-off alternate if required, destination and destination alternates

-

for flights of more than 2 HRs the forecast must cover en-route alternates.

• Information of specified en-route weather phenomena (SIGMET) Concerning volcanic ash clouds and tropical cyclones must be based on advisory information provided by Volcanic Ash Advisory Centers (VAACs) and Tropical Cyclone Advisory Centers (TCACs)

© Lido 2010

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Information (for example: windshears, icing, inversion) for short flights below FL100, FL150 in mountainous areas or as specified by the local meteorological office.

2.3 Reduced Flight Documentation c In general, a flight shall not be commenced until the provision of meteorological information satisfies the pilot-in-command. For deviation in terms of content and validity of meteorological information for the intended type of operation refer to the respective Airline Operation Manual.

2.4 Contents of Flight Documentation 2.4.1 Significant Weather Chart (SIGWX) Charts available from World Area Forecast Center (WAFC) London: • Low Level (SWL): SFC-10000ft (15000ft in mountainous areas) with fronts (not provided by all states and not disseminated internationally). Note: Upper limits of SWL provided by local country MET services can differ • Medium Level (SWM): FL100 to FL250 (only available for dedicated areas, defined in ICAO Annex 3) • High Level (SWH): FL250 to FL630 Medium/High Charts Include: • Tropical Cyclone when mean surface wind speed ≥ 34KT • Severe squall lines • Moderate or severe turbulence (in cloud or clear air) • Moderate or severe icing • Widespread sand/duststorm • Cumulonimbus clouds associated with thunderstorm and with items above • Flight level of tropopause • Jet streams • Information on the location of volcanic eruption

© Lido 2010

• Information on the location of an accidental release of radioactive materials into the atmosphere.

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High level significant weather chart (SWH) example

© Lido 2010

Medium level significant weather chart (SWM) example

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Low level significant weather chart (SWL) example

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Legend for significant weather charts (SIGWX) General Significant Weather Charts (SIGWXs) are issued by the World Area Forecast Centers (WAFC) in London and/or Washington. • Fixed Time/Date Forecast Chart. Valid times are: 06, 12, 18 and 00 UTC. Head

• Units used: knots; altitude in FL; • CB implies TS, GR, moderate or severe turbulence and ice. • Check SIGMETs, advisories, ASHTAM and NOTAM for volcanic ash

Tropopause heights

Indication numbers are in squares followed by moderate or severe turbulence symbols and FL.

CAT Area

The position/axis of a jet stream is shown as a heavy solid line with wind speed marks and change bars. The jet stream axis begins/ends at the point where a wind speed of 80KT is forecast. The change bar denotes a change of speed of 20KT. The FL of the 80KT isotach above and below the maximum wind speed level is shown. (Only speed of 120KT or more will contain vertical depth information.)

Cloud height

330, 350, xxx = FL of top, 270 xxx xxx = FL of the base of significant weather. xxx indicates that the top / base is outside of the height range of the chart.

© Lido 2010

Cloud amount, type and height

Sky cover is shown as FEW (<25%), SCT (25 - 50%), BKN (>50 <100%), OVC (100%). Cloud amount in okta still used for graphical representation on SWC in METEO offices. For cloud types ICAO abbreviations are used. Usually convective clouds as CB, CU and AC are presented only, other types as layers/LYR. CBs are described as isolated/ISOL, occasional/OCNL, frequent/FRQ and embedded/EMBD in clouds or haze.

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14-OCT-2010 Fronts and Significant Areas Cold front, moving direction and speed

Warm front, moving less than 5KT Occluded front Quasi stationary front Position, speed and level of maximum wind Wind arrows indicate the maximum wind in jet and the flight level at which it occurs. If the maximum wind speed is 120KT or more, the flight levels between which winds are greater than 80KT is placed below the maximum wind level. In the example, winds are greater than 80KT between FL220 and FL400. Severe squall line Convergence line Intertropical convergence zone Boundary of significant weather CAT areas Mountain waves Widespread strong surface wind – This symbol refers to wind speeds exceeding 30KT. Symbols of Significant Weather Moderate/severe turbulence Moderate/severe icing Thunderstorms Tropical cyclone Volcanic eruption, including name & position (lat/long) of volcano, date and time of first eruption Additional Symbols used on MET Offices Charts Drizzle Rain Snow Hail Shower Freezing precipitation Severe sand or dust storm Widespread sand or dust storm Widespread mist / fog © Lido 2010

Widespread haze Widespread blowing snow

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Widespread smoke Freezing level State of the sea, wave height in ft Sea surface temperature Mountain obscuration Radioactive materials in the atmosphere - Following information should be included at the side of the chart: radioactive materials symbol; latitude/longitude of accident site; date and time of accident; check NOTAM for further information. 2.4.2 Upper Wind and Temperature Chart

Upper wind and temperature chart (example) Legend for upper wind and temperature chart General Upper wind forecasts are provided by the WAFC London/Washington. Observations are made twice a day at 00 and 12 UTC Valid times are 06, 12, 18, and 00 UTC.

Standard Levels

FL50 / 850hPa

FL100 / 700hPa

FL140 / 600hPa

FL180 / 500hPa

Fl240 / 400hPa

FL300 / 300hPa

FL340 / 250hPa

FL390 / 200hPa

FL340 / 150hPa

FL530 / 100hPa

© Lido 2010

Head

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Meteorology Units

Wind speed in knots. Temperature in °C are negative unless prefixed by “+” or PS.

Spotwind / Temperature

Wind direction is in degrees true, e.g.

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Spotwind 270°/95KT, temperature 57°C. Alternate Charts

Additional authorized methods of presentation are tabular or cross-section wind forecasts.

2.4.3 ICAO Codes - TAF & METAR Issue and valid time of aerodrome forecast and reports are according to World Meteorological Organization (WMO) / ICAO codes and schedule. 2.4.3.1 Operational Meteorological Information (OPMET) Data Bank Interrogation Designator 2-letter codes used to store and retrieve information in data banks as follows: OPMET Designator

Meaning

FA FC FK FT FV SA SP WA WC WS WV

GAMET TAF less than 12HRs Tropical Cyclone Advisory (TCA) TAF up to 30 HRs Volcanic Ash Advisory (VAA) METAR SPECI AIRMET SIGMET: Tropical Cyclnone SIGMET SIGMET: Volcanic Ash

2.4.3.2 Delayed/Corrected OPMET If necessary the heading may include the group. RRA or RTD for delayed, CCA or COR for corrected, AAA or AMD for amended. If additional delay, corrected or amended bulletins, they are identified by RRB, RRC or CCA, CCB or AAB, AAC. 2.4.3.3 Aerodrome Forecast - TAF The period of validity should not be less than 6 HRs, no more than 30 HRs. TAFs valid for less than 12 HRs should be issued every 3 HRs and those valid for 12 to 30 HRs every 6 HRs. Amended/Cancelled TAF (AMD, CNL) Example: TAF AMD EBBR 11100Z 1106/1206 CNL = (Amended TAF for EBBR issued at 11th 1100Z, cancels the previous issued TAF valid on 11th 0600 -12th 0600). When an aerodrome forecast required for flight planning and documents cannot be obtained from the Meteorological Office responsible for its issue, the Meteorological Office at the aerodrome of departure should, if possible, prepare a provisional forecast. The provisional forecast should be recorded in the flight documentation with its origin. Change Groups Sheet 471325

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Provisional TAF FC / FT

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Change of prevailing conditions in TAF/SA (Trend forecast) Only those weather elements which may change are given! Change indicator becoming or temporary and from hour/minutes are used in TAF only. Change indicator

Explanation

BECMG (becoming)

Changes where the meteorological conditions are expected to reach or pass through specified threshold values at a regular or irregular rate and at an unspecified time during the time period (starting 2300Z on the 8th day and ending at 0100Z on the 9th day). Example TAF - FT: NZZO 081140Z 0812/0918 VRB02KT 1800 BR BECMG 0823/0901 00000KT 0500 FG VV002

TEMPO (temporary)

Describes expected frequent or infrequent temporary fluctuations in meteorological conditions which reach or pass specified threshold values and last for a period of less then 1 hour in each instance and in the aggregate, cover less than half of the fluctuation period (from 1800Z on the 8th day to 2300Z on the 8th day). Example TAF - FC: LFPG 081140Z 0812/0918 29010KT 5000 NSW TEMPO 0818/0823 1500 SHSN =

PROB (probability)

Probability in percent of occurrence of an alternative weather development and the time period (from 1000Z on the 9th day to 1200Z on the 9th day). PROB30/40 alone or in combination with TEMPO are used. Example TAF - FT 18/24: VAAB 081140Z 0812/0918 26018KT 3000 RA SCT012 BKN030 PROB40 0910/0912 25028G40+RA =

Time Divider FM (from)

Where one set of prevailing weather condition is expected to change significantly and more or less completely to a different set of conditions, the period of validity should be subdivided into a self-contained period giving the time group in whole hour and minutes UTC when the change is expected to occur (at 1000Z on the 9th day). The period following from should be self-contained and all forecast conditions given before should be superseded. Example TAF - FT: KBGR 081140Z 0812/0918 35008KT P6SM SCT200 FM091000 03005KT P6SM BKN120 =

a Optional Groups in TAF Indicator TN or TX followed by degrees Celsius and day of month and time in HRs UTC (M if
a Turbulence and icing

According to ICAO not included anymore. Tables are kept as sporadically still appearing in TAFs.

© Lido 2011

a MAX / MNM Temperature Forecast (T)

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12-MAY-2011 a Optional Groups in TAF a Turbulence a a a a a a a a a a a a a a a Icing

a a

Coded 6-figure group 1st figure: Group indicator 6 2nd figure: Type of icing 0 = none 1 = light 2 = light in cloud 3 = light in precipitation 4 = moderate 5 = moderate in cloud 6 = moderate in precipitation 7 = severe 8 = severe in cloud 9 = severe in precipitation 3rd to 5th figure: Height of lowest icing level in hundreds of feet above aerodrome elevation. 6th figure: Thickness of icing layer in thousands of feet; exception: 0 = top of cloud Example: 660083 = moderate in precipitation, from 800 upwards in layer 3000ft thick.

2.4.3.4 Aerodrome Report - METAR / SPECI METARs are issued half hourly or hourly, e.g. 0920 / 0950, 1400 / 1430, or 1600 / 1700. Example of METAR - SA: METAR SBPA 140000Z 01002KT 4500 RA BKN002 SCT 040 OVC100 20/20 Q1008= SPECI and Local Routine or Special Report Issued where the meteorological conditions are reaching or passing through a specified threshold. SPECI are disseminated the same way as METAR. Local routine/special report is sent to the local ATC and Airline Operators and other users of the aerodrome. Example of SPECI - SP:

© Lido 2011

a a a a a a a a a a a a

Coded 6-figure group 1st figure: Group indicator 5 2nd figure: Type of turbulence 0 = none 1 = light 2 = moderate in clear air, infrequent 3 = moderate in clear air, frequent 4 = moderate in cloud, infrequent 5 = moderate in cloud, frequent 6 = severe in clear air, infrequent 7 = severe in clear air, frequent 8 = severe in cloud, infrequent 9 = severe in cloud, frequent X = extreme (US AFB TAF only) 3rd to 5th figure: Height of lowest turbulence level in hundreds of feet above aerodrome elevation. 6th figure: Thickness of turbulent layer in thousands of feet; exception: 0 = top of clouds Example: 590200 = severe in cloud, frequent, from 2000ft up to top of cloud.

SPECI CYKF 132356Z AUTO 14009KT 9SM –RA BKN026 15/12 A3001=

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Supplementary Information to METAR / SPECI Information concerning recent weather (RE...), windshear (WS RWY03), RWY condition (see decoding MET Winter Operation) Example of runway report (in bold numbers): METAR LSZH 151450Z 10004KT 040V140 6000 SCT017 M09/M11 Q1028 R88710195 NOSIG Automatically Generated METAR / SPECI Systems should only be used during non-operational HRs of the aerodrome. Additional codes used in AUTO-METAR: • AUTO: at the beginning of the message • VIS: NDV = no directional variation can be given. • WEATHER: UP = unidentified precipitation; type of precipitation cannot be identified. • missing DATA: /// = e.g. cloud type cannot be identified • CLOUDS: NCD = no clouds detected • RECENT WX: REUP = recent precipitation; type not identified Example: METAR EHAK 132355Z AUTO 10022KT 9999NDV NCD 11/08 Q1019= 2.4.3.5 Aerodrome Trend Forecasts The Trend Forecast shall indicate significant changes in weather elements and be appended to METAR or SPECI. When no change is expected to occur, the term NOSIG should be used. The Trend Forecast shall begin with the change indicators BECMG or TEMPO. The period during which, or the time at which, the change is forecast to occur shall be indicated by “FM”, “TL” or “AT” followed by the time group in hour and minute. The period of validity is normally 2 HRs from the nominal observation time of the report to which the TREND is appended. NOSIG: no significant changes in wind/VIS/weather type/ clouds. Example TREND - SA: METAR EICK 14000Z 08009KT 1600 –RADZ OVC002 09/09 Q1008 TEMPO 0800 BKN001= 2.4.3.6 Additional Information to ICAO Codes Visibility (VIS) / Prevailing Visibility VIS: The greatest distance to be seen. Prevailing VIS: VIS reached within at least half the horizon circle or half of the surface of the aerodrome. These areas could be contiguous or non-contiguous sectors. Runway Visual Range (RVR) RVR reports for take-off and landing by tower and ATIS are measured for each third of the runway, if available, and given from TDZ-MID-END. Reported in local routine and special reports: only TDZ or TDZ-MID-END. For METAR/SPECI: only TDZ Differences from ICAO Codes © Lido 2011

For regional differences from ICAO codes: refer to MET-Section of respective RSIs and CRARs

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14-OCT-2010 2.5 SIGMET / AIRMET

2.5.1 SIGMET General SIGMETs are warnings of actual and/or forecasted weather phenomena, hazardous to aircraft in-flight. The validity shall be not more than 4 HRs (for TC, VA 6 HRs) and should be cancelled when the phenomena are no longer occurring or expected to occur. The area affected is always specified by making reference to a CTA or FIR, even if the hazard is occurring in the UIR. Information of severe weather phenomena like: TS, TC, TURB, ICG, MTW, HVY DS/SS, RDOACT CLD (radioactive cloud). Example of WS: YUDD SIGMET 2 VALID101200/101600 YUSO YUDD SHANLON FIR/UIR OBSC TS FCST S OF N54 TOP FL390 MOV E WKN 2.5.2 AIRMET General Information for SFC WSPD, SFC VIS, TS, MT OBSC, BKN CLD, (CB, TCU) MOD ICE/TURB/MTW for FLTs below FL100 or FL150 (or higher) in mountainous areas. Example of WA: YUDD AIRMET 1 VALID 151520/151800 YUSOYUDD SHANLON FIR ISOL TS OBS N OF S50 TOP ABV FL100 STNR WKN 2.5.3 SIGMET / AIRMET - ICAO Code Content • Location indicator of FIR • Message identification and sequence number • Validity (date-time group) • Location indicator of originator (Meteorological Office) • Location indicator of area affected • Significant weather type • Indication if observed or forecast • Location • Flightlevel affected and extend • Expected movement • Change in intensity for volcanic ash clouds/tropical cyclones • Forecast position of TC, VA at the end of validity period or cancellation refering to its identification 2.5.4 Tropical Cyclone SIGMET - TC Term for non-frontal cyclone originating over tropical or sub-tropical waters with organized convection and cyclonic surface wind circulation. Example of WC: YUCC SIGMET 3 VALID 251600/252200 YUDOYUCC AMSWELL FIR TC GLORIA OBS AT 1600Z N2706 W07306 CB TOP FL500 WI 150NM OF CENTER MOV NW 10KT NC FCST 2200Z TC CENTER N2740 W07345

© Lido 2010

2.5.5 Volcanic Ash SIGMET - VA Warning of eruption, extend of ash clouds. Example of WV: Sheet 384892

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YUDD SIGMET 2 VALID 211100/211700 YUSOYUDD SHANLON FIR/UIR VA ERUPTION MT ASHVAL LCA S1500 E07348 VA CLD OBS AT 1100Z FL310/450 APRX 220KM BY 35KM S1500 E07348 - S530 E07642 MOV ESE 65KM FCST 1700Z VA CLD APRX S1506 E07500 - S1518 E08112 S1712 ⇒

Communication General Information

4.4 Weather Reports

2.5.6 SIGMET / AIRMET U.S. System Information concerning to SIGMET / AIRMET U.S. system are found in appropriate CRAR USA.

2.6 Aerodrome Warnings 2.6.1 Aerodrome Warnings - AD Warning Aerodrome Warnings are issued and sent to the local ATC and Airline Operators and other users of the aerodrome in case of occurrence or expected occurrence of: TC (expected WSPD >34KT), TS, GR, SN, SA/DU, VA, TSUNAMI 2.6.2 Wind Shear Warnings - WS WRNG Are issued and sent to the local ATC and Airline Operators and other users of the aerodrome and as Supplemental Information to METAR/SPECI.

3 In-Flight Information 3.1 General In today‘s international aviation it is of utmost importance to be permanently updated by the latest operational meteorological information (OPMET including SIGMET, AIRMET). In addition to the weather broadcasting stations on HF and VHF, there are several aeronautical networks that provide data link between aircraft and ground stations.

3.2 Air to Ground Datalink Aircraft Communication Addressing and Reporting System (ACARS) allows the exchange of weather forecasts and reports via the worldwide Teletype networks or Automatic dependent Surveillance (ADS). ⇒

Communication General Information

4 ATC Communication

3.3 ATIS / VOLMET 3.3.1 ATIS (Automated Terminal Information Service) ATIS is the automatic provision of current, routine information to arriving and departing aircraft throughout 24 HRs or a specified portion thereof. It contains weather reports, runway and approach aid in use, QNH/QFE, runway / taxiway conditions and other information useful to pilots.

© Lido 2010

Normally the information will be updated every hour or every half hour, indicated by a changing phonetic code at the beginning of the information (ALPHA, BRAVO, etc.) The decoding of ATIS information does not differ from TAF/METAR, except the RWY wind is reported in degrees magnetic, similar to the wind reporting from TWR. Additional information concerning approach, climb out (AIRMET, danger areas, etc.), and airport constraints (TWY, frequencies, winter operation etc.) are reported. ATIS is provided by voice via VHF broadcast on the voice feature of a VOR station near the airport or on a separate VHF frequency and – where available – via data link (D-ATIS).

Sheet 384892

LSY Standard (jetww)

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MET

General Part

12-MAY-2011

3.3.2 VOLMET (Meteorological Information for Aircraft in-Flight) VOLMET is another meteorological broadcast for one single VOLMET station includes METAR reports of several airports in the vicinity of the station. • Continuous VOLMET broadcasts (normally on VHF) contains current METAR and SPECI, together with trend forecasts where available. • Scheduled VOLMET broadcasts (normally on HF), contains current METAR and SPECI, together with trend forecasts where available and, where so determined by regional air navigation agreement, TAF and SIGMET • D-VOLMET contains current METAR and SPECI, together with trend forecasts where available, TAF and SIGMET, special air-reports not covered by a SIGMET and, where available, AIRMET. For availability of D-ATIS see IACs. For VHF and HF-FREQs and information about ATIS and VOLMET stations refer to the paragraph “Appendix” of the respective Lido/RouteManual RSIs

4 Aircraft Observations and Reports a The following observations shall be made: a

• routine aircraft observations during en-route and climb out phases of the flight

a

• special / non-routine aircraft observations during any phase of the flight

d

4.1 Reporting Of Aircraft Observations During Flight a Aircraft observations shall be reported using the following means: a

•

air-ground data link (ADS/CPDLC): This is the preferred mode of reporting

a

• voice communication: This shall be used only if the air-ground data link is not available or appropriate.

a Aircraft observations shall be reported during flight at the time the observation is made or as soon thereafter as is practicable.

4.2 Routine Aircraft Observations a Routine Aircraft Observations are communicated when sending a Routine Air Report (AIREP). ⇒

Communication General Information

4.3.1 AIREP (ICAO DOC 4444/7030)

a Frequency of reporting: a When air-ground data link is used and automatic dependent surveillance (ADS) or secondary surveillance radar (SSR) Mode S is being applied, automated routine observations are made every 15 minutes during the en-route phase and every 30 seconds during the climb-out phase for the first 10 minutes of the flight. When voice communication is used, routine meteorological observations by aircraft are made only during the enroute phase of the flight at ATS reporting points or intervals a

• at which the applicable ATS procedures require routine position reports, and

a

• which correspond most closely to intervals of one hour of flying time

a Exemptions from reporting: a Where voice communication is used, an aircraft is exempted from making routine observations when: • the aircraft is not equipped with RNAV equipment; or

© Lido 2011

a

Sheet 471327

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a

• the flight duration is 2 hours or less; or

a

• the aircraft is at a distance equivalent to less than one hour of flying time from the next intended point of landing; or

a

• the altitude of the flight path is below 1500m (5000 ft)

a Note: When air-ground data link is used, no exemptions are to be applied.

4.3 Special and Other Non-Routine Aircraft Observations c Special Aircraft Observations Special observations are required to be made by all aircraft operating on international air routes whenever the following conditions are encountered or observed: a

• severe turbulence; or

a

• severe icing; or

a

•

a

•

severe mountain wave; or thunderstorms that are:

a

-

obscured; or

a

-

embedded; or

a

-

widespread; or

a

-

in squall lines

a

• heavy duststorms or heavy sandstorms; or

a

• volcanic ash cloud; or

a

• pre-eruption volcanic activity or volcanic eruption.

c Other non-routine observations Other non-routine aircraft observations are made when meteorological conditions are encountered which are different from those listed under special aircraft observations (e.g. wind shear) and which, in the opinion of the pilot-in-command, may affect the safety or markedly affect the efficiency of other aircraft operations. These observations shall be made through voice communications by advising the appropriate ATS unit as soon as practicable. In the case of wind shear reports: a

• the aircraft type must be included;and

a

• pilots shall inform appropriate ATS units as soon as practicable if forecast wind shear conditions are not encountered

a Note: Icing, turbulence and, to a large extent, wind shear are elements which, for the time being, cannot be satisfactorily observed from the ground and for which in most cases aircraft observations represent the only available evidence.

5 Volcanic Activity / Ashreports

© Lido 2011

5.1 General Volcanic ash clouds may severely affect the safety of flight operation. Corresponding warnings are promulgated in the form of NOTAM, SIGMETs, ASHTAMs, and Volcanic Ash Advisories and/or in activation of a Volcanic Ash Contingency Plan if developed. It is emphasised that a volcanic ash encounter is potentially extremely hazardous and areas of known contamination shall generally be avoided. Volcanic ash may extend for several hundred miles and can reach up to the stratosphere. The contamination may not be visible. Volcanic ash may block the Pitot-static system of an aircraft, resulting in unreliable airspeed indications; and

Sheet 471327

LSY Standard (jetww)

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MET

General Part

12-MAY-2011

Braking conditions at airports where volcanic ash has recently been deposited on the runway will affect the braking ability of the aircraft. Volcanic Ash Advisory Centers (VAACs) as part of the International Airways Volcano Watch (IAVW) have been set up by ICAO, responsible for advising aviation of location and movement of clouds of volcanic ashes in their areas: • London • Toulouse • Tokyo • Darwin • Wellington • Anchorage • Montreal • Washington • Buenos Aires Observation by pilots of pre-eruption volcanic activity, or eruption or volcanic ash cloud shall be reported to ATS and recorded on a special air-report form possibly provided on board. Post flight: The completed report shall be delivered (or filled out at) to the aerodrome Meteorological Office by the pilots.

5.2 ASHTAM Provides information on the status/changes of activity of a volcano using a level of alert. The maximum validity is 24 hours. For decoding on an ASHTAM refer to: ⇒

Meteorology General Information

8.4 ASHTAM Decoding

6 Potential Flight Hazards 6.1 General There are severe weather situations, mainly caused through convective clouds (CU, CB) which create heavy turbulence, precipitation, and icing. Throughout all levels you may encounter dangerous conditions (wind shears close to ground or Clear Air Turbulence (CAT) along jet streams). Details are outlined in the following paragraphs.

6.2 Turbulence

MODERATE

Moderate changes in ACFT attitude and/or altitude may occur but ACFT remains in positive control at all times. Accelerometer readings 0.5g to 1.0g. Difficulties in walking. Loose objects move about. Strain felt against belt. Reported as “Turbulence moderate”.

SEVERE

Abrupt changes in ACFT attitude and/or altitude. ACFT may be out of control for short periods. Large variation in airspeed. Accelerometers readings > 1.0g. Occupants forced violently against seatbelts. Loose objects tossed about. Reported as “Turbulence severe”. Sheet 471328

*471328* LSY Standard (jetww)

© Lido 2011

6.2.1 Turbulence Grade Classification LIGHT Condition less than moderate turbulence. Changes in accelerometer readings less than 0.5g at the Center of Gravitiy (CG). Reported as “Turbulence light”.

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6.2.2 Clear Air Turbulence (CAT) Encounter 6.2.2.1 General World Area Forecast Centers (WAFC) London and Washington are providing the most accurate information to users: Significant Weather Charts (SIGWX) for high and medium levels, upper wind and temperature charts are provided. 6.2.2.2 Clear Air Turbulence Phenomenon Clear Air Turbulence (CAT) layers are found along front lines and their jet streams. These areas of vertical exchange of air mass are the most dynamic and significant where two tropopauses overlap each other. When turbulence becomes excessive, an altitude change is more efficient than a track change. 6.2.2.3 Forecast Presentation The forecast of Clear Air Turbulence (CAT) areas (dashed lines) on SIGWX provide no information of light turbulence. It is a fact that temporary change of a certain level has the greatest influence on the development of CAT. 6.2.2.4 Convective Induces Turbulences Due to heat radiation from different ground states, e.g. forests, lakes, rocks, RWYs etc. Climb out and approach phase can be uncomfortable. 6.2.2.5 Topographically induced Turbulence In strong wind conditions behind hills, buildings, etc. These conditions may also cause wind shear. 6.2.2.6 Wake Turbulence Behind aircraft consists of two counter-rotating cylindrical vortices. The pressure differential between the upper and the lower side of the wing triggers the roll up of the airflow aft of the wing, resulting in swirling air masses trailing downstream of the wing tips. Pilots should avoid a region within less than 200ft of the vortex core. When flying on track systems in oceanic or remote areas offset procedures (i.e. SLOP) may be applied.

6.3 Precipitation, Icing 6.3.1 General Precipitation can severely reduce Visibility (VIS) and can give a false optical illusion during landing phase. A flooded, contaminated RWY may deteriorate the braking coefficient towards zero (aquaplaning). 6.3.2 Categories of Precipitation • Vapor Consists of very small drops of water which form haze, mist, and fog. This form of precipitation reduces the VIS drastically. • Liquid Forms of precipitation are drizzle and rain. • Frozen

© Lido 2011

Forms are snow, snow grains, snow pellets, ice pellets, and hail. 6.3.3 Classification of Precipitation Intensity With regard to precipitation, detection thresholds expressed in Millimeter per Hour (mm/h) are given for some sensors. The World Meteorological Organization (WMO) reporting thresholds for light, moderate and heavy precipitation are shown in Table.

Sheet 471328

LSY Standard (jetww)

190

Meteorology Intensity

Drizzle

Rain

Snow

Light

< 0.1 mm/h

< 2.5 mm/h

< 1.0 mm/h

Moderate

0.1 and < 0.5 mm/h

2.5 and < 10 mm/h

1.0 and < 5 mm/h

Heavy

0.5 mm/h

10 mm/h

5 mm/h

MET

General Part

12-MAY-2011

6.3.4 Airframe Categories of Icing • Rime Thin milky film of frozen vapor. • Frost Rough, milky and opaque ice formed by the instantaneous freezing of small water droplets or snow flurries. • Clear ice Glossy, clear, or translucent ice formed by slow freezing of water droplets.

6.4 Special Winter Phenomena 6.4.1 Thunderstorms, CB / TCU Turbulence, hail, snow, lightning, sustained up- and downdrafts, icing conditions - are all present in thunderstorms. Up- and downdrafts extend far beyond the visible storm cloud. Severe turbulence can be expected up to some distance from large thunderstorms. 6.4.2 Downdraft and Microburst (MB) A Downdraft is a relative small scale downward current of air; often observed on the lee side of large objects restricting the smooth flow of the air or in precipitation areas in or near Cumuliform Clouds. Microburst are small-scale intense cold air downdrafts out of cumulus clouds or thunderstorm cells which, on reaching the surface, spread outward in all directions from the downdraft center. This causes the presence of vertical and horizontal wind shear, especially at low altitude within some 1000ft of the ground. Microburst either occur as wet microburst carrying precipitation to the ground or as dry microburst descending from cumulonimbi or towering cumuli with a high cloud base (around 10000ft), typically in desert regions. Size: The strong downdraft is typically less than 1NM in diameter; the horizontal outflow can extend to approx. 4NM in diameter. Intensity: The downdrafts can be as strong as 8000ft/MIN. Horizontal winds speeds near the surface can reach up to 100KT. Visual sign: They may be embedded in heavy rain associated with convective clouds or little or no precipitation. The main flight hazards of a microburst are: • severe low level wind shear, • the strong downdraft, © Lido 2011

• severe turbulence at the gust front.

Sheet 471329

*471329* LSY Standard (jetww)

MET

General Part

12-MAY-2011

200

Meteorology

Other hazards found below thunderstorms may join the already critical situation, like heavy rain, hail, aquaplaning, lightning, and tornadoes. Wind shear may be horizontal, vertical wind shear, and up and downdraft shears. A flight through a microburst lasts only for seconds. The history of an aircraft encountering a microburst strongly depends on its path through the microburst and the phase of flight. 6.4.2.1 Microburst on final

A pilot penetrating a microburst during final approach will first experience a strong headwind, the aircraft first balloons above the glide slope due to air speed rise shear. Entering the downdraft there is air speed loss shear, downdraft shear, and the vertical displacement by the downdraft, which altogether leads to a dramatic loss of height. Finally a strong tailwind signifies another air speed drop shear. Additionally the aircraft may encounter turbulence at the gust front. 6.4.2.2 Microburst after Take-Off

An aircraft taking off in a microburst will first encounter a stronger headwind and thus a speed increase (1). After take-off, upon entering the tailwind area speed drops and the nose has to be lowered (2). In case of further downdraft activity the airplane may continue to sink and ground impact becomes imminent (3).

© Lido 2011

Detection: Due to their small size, short lifespan and the fact that they often occur over areas without surface precipitation, microburst are not easily detectable using conventional weather radar or wind shear alert system. Look out for signs of convective weather, like CU, TCu, showers, and virga. Read (and issue) pilot reports, but do not rely on them too much, since the microburst changes by the minute. The bending of trees, dust, and sand in the air may be the only up to date information on the wind field around the aerodrome. Sheet 471329

LSY Standard (jetww)

Meteorology

210

MET

General Part

22-SEP-2011

6.4.3 Mountain Waves (MTW) Mountain waves occur when air is being blown over a mountain range. As the air hits the upwind side of the range, it starts to climb, thus creating a smooth updraft which turns into a turbulent downdraft as the air passes the crest of the ridge. From this point, for many miles downwind, there will be a series of down- and updrafts accompanied by moderate to severe turbulence. 6.4.4 Wind Shears Wind shear conditions are normally associated with the following phenomena: • thunderstorms, microburst, tornado, and gusts. • frontal surfaces • mountain waves • strong wind coupled with local topography • see breeze fronts • low-level temperature inversions 6.4.5 Inversion An increase of temperature with height - a reversal of the normal decrease with height in the troposphere. In inversions windshear may be encountered.

7 Winter Operation 7.1 Fluids and Procedures 7.1.1 De-/Anti-Icing Instructions Generally, de-/anti-icing instructions, information and procedures used by the flight crews are published in the respective manual. For ground personnel dealing with aircraft de-/anti-icing, a separate "De-/ Anti-icing Manual" (DAM) has been established. Before aircraft treatment and de-/anti-icing fluid application, the pilot must check that the type of aircraft is known by the ground personnel. During off-gate de-icing, two-way communication between pilot and de-/anti-icing operator/supervisor must be established prior to de-/anti-icing treatment. This shall be accomplished either by intercom or by VHF radio. All de-/anti-icing actions must be entered in the aircraft log. The appropriate information will be communicated by the ground personnel and the respective de-/anti-icing code (fluid type, mixture, and the time the final de-/anti-icing step commenced, e.g. “Type II, 75/25, 1155”), shall be entered by the flight crew into the Technical Log on the “Complaint” side of the log slip. 7.1.2 De-Icing and Anti-Icing Procedures De-icing is a procedure by which frost, slush, snow, or ice is removed from the aircraft in order to provide clean surfaces. Anti-icing is a precautionary procedure which provides protection against the formation of frost or ice and accumulation of snow or slush on treated surfaces of the aircraft for a limited period of time (hold-over-time). De/anti-icing is a combination of de-icing and anti-icing and may be performed in one or two steps. Normally, if not otherwise requested by the pilot, the entire aircraft will be completely de-iced and cleaned of any frost, slush, snow, and ice. The spray operator is aware that the forward fuselage (nose to forward passenger/service door section) requires special attention in order to avoid soiled cockpit windshields. This area is normally cleaned by hot water only.

Sheet 515542

*515542* LSY Standard (jetww)

© Lido 2011

For exceptions/operating limits and for local frost prevention or removal, refer to OM-B/AOM.

MET

General Part

22-SEP-2011

220

Meteorology

If, however, the cockpit windshields and/or the nose of the aircraft should be soiled by de-/anti-icing fluid, the area must be cleaned by rinsing clear hot water and in addition, the windshields shall be cleaned with a soft cloth prior to departure. Windshield wipers, however, shall not be used for this purpose. a Anti-icing Fluid

De-icing Fluid

a

• Mixture of water and Type I fluid (Note1)

• Heated water

a

• Premix Type I fluid (Note1)

• Mixture of water and Type I fluid

a

• Type II fluid, Type III fluid or Type IV fluid

• Premix Type I fluid

a

• Mixture of water and Type II fluid, Type III fluid or Type IV fluid

• Type II fluid, Type III fluid or Type IV fluid

a Note 1: Fluids must be heated to ensure a temperature of 60°C minimum at the nozzle.

• Mixture of water and Type II fluid, Type III fluid or Type IV fluid Note: De-icing fluid is normally applied heated to ensure maximum efficiency.

7.1.2.1 De-Icing / Anti-Icing Checks Following the de-icing/anti-icing procedures and prior to takeoff, the critical aeroplane surfaces shall be clean of all frost, ice, slush, and snow accumulations in accordance with the following requirements. For specific aeroplane types additional requirements may exist e.g. special clear ice checks, such as tactile checks on wings. These special checks are not covered by the contamination check. Aeroplane operators shall make arrangements for suitably qualified personnel to meet these requirements.

© Lido 2011

General aeroplane requirements after de-icing/anti-icing Wings, tail and control surfaces

Wings, tail and control surfaces shall be free of ice, snow, slush, and frost except that a coating of frost may be present on wing lower surfaces in areas cold soaked by fuel between forward and aft spars in accordance with the aircraft manufacturers published manuals. (Note1)

Pitot heads and static ports

Pitot heads and static ports shall be clear of ice, frost, snow and fluid residues.

Engines

Engine inlets, exhaust nozzles, cooling intakes, control system probes and ports shall be clear of ice and snow. Engine fan blades or propellers (as appropriate) shall be clear of ice, frost and snow, and shall be free to rotate.

Air conditioning inlets and exits

Air conditioning inlets and exits shall be clear of ice, frost and snow. Outflow valves shall be clear and unobstructed.

Landing gear and landing gear doors

Landing gear and landing gear doors shall be unobstructed and clear of ice, frost and snow.

Fuel tank vents

Fuel tank vents shall be clear of ice, frost and snow.

Fuselage

Fuselage shall be clear of snow, slush or ice. Frost may be present in accordance with the aircraft manufacturer’s manuals.

Nose / Radome Area and Flight Deck Windows

Any significant deposits of snow, slush, or ice on the windscreens or on areas forward of the windscreens shall be removed prior to departure. Heated flight deck windows will not normally require de-icing.

Note 1

Frost or any other contamination is not acceptable on the lower side of the horizontal stabiliser and elevator, unless specified otherwise in the AFM or other aircraft manufacturer's documentation.

Flight control check A functional flight control check using an external observer may be required after de-icing/anti-icing depending upon aeroplane type (see relevant manuals). This is particularly important in the case of an aeroplane that has been subjected to an extreme ice or snow covering.

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Post De-icing/Anti-icing Check An aeroplane shall not be dispatched after a de-icing/anti-icing operation until the aeroplane has received the following visual check by a trained and qualified person. This check shall cover wings, horizontal stabilizer, vertical stabilizer and fuselage, plus all other parts of the aeroplane on which a de-icing/anti-icing treatment was performed according to the requirements identified during the contamination check. The check shall be performed from points offering sufficient visibility of all prescribed surfaces (e.g. from the de-icer itself or other equipment suitable for gaining access). Any contamination found, shall be removed by further deicing/anti-icing treatment and the check repeated. Before take-off the commander must ensure that he has received confirmation that this Post De-icing/Anti-icing Check has been accomplished. a Where the de-icing provider is carrying out the de-icing/anti-icing process and also the Post De-icing/ Antiicing Check, it may either be performed as a separate check or incorporated into the de-icing operation as defined below. The de-icing provider shall specify the actual method adopted, where necessary by customer, in his winter procedures: a

• As the de-icing/anti-icing operation progresses the De-icing Operator will closely monitor the surface receiving treatment, in order to ensure that all forms of frost, ice, slush or snow (except as may be allowed in the AFM and/or AMM) are removed.

a

• Once the operation has been completed, the De-icing Operator will carry out a close visual check of the surface where treatment commenced, in order to ensure it has remained free of contamination (this procedure is not required under ‘frost only’ conditions).

a

• Where the request for de-icing/anti-icing did not specify all of the following surfaces, i.e. wing, horizontal stabilizer, vertical stabilizer and fuselage, the surfaces omitted from the request shall also receive a close visual check at this time, in order to confirm that they have also remained free of contamination.

a

• Any evidence of contamination that is outside the defined limits shall be reported to the Commander immediately. Pre-takeoff Check The Commander shall continually monitor the weather conditions after the performed de-icing/anti-icing treatment. Prior to takeoff he shall assess whether the applied holdover time is still appropriate and/or if untreated surfaces may have become contaminated. This check is normally performed from inside the flight deck. Pre-takeoff Contamination Check This is a check of the critical surfaces for contamination. This check shall be performed when the condition of the critical surfaces of the aeroplane cannot be effectively assessed by a pre-takeoff check or when the applied holdover time has been exceeded. This check is normally performed from outside the aeroplane. The alternate means of compliance to a pre-takeoff contamination check is a complete de-icing / antiicing re-treatment of the aeroplane. Dried fluid residues when the aeroplane has not been flown after anti-icing Dried fluid residue could occur when surfaces have been treated but the aeroplane has not subsequently been flown and not been subject to precipitation. The fluid may then have dried on the surfaces. In such situations the aeroplane must be checked for residues from de-icing / anti-icing fluids and cleaned as necessary. Proper account should be taken of the possible side-effects of fluid use. Such effects may include, but are not necessarily limited to, dried and/or re-hydrated residues, corrosion and the removal of lubricants.

Communication prior to starting De-icing/Anti-Icing Treatment • Before de-icing/anti-icing, the Commander shall be requested to confirm the treatment required (areas to be de-iced, anti-icing requirements, special de-icing procedures)

Sheet 515543

*515543* LSY Standard (jetww)

© Lido 2011

7.1.2.2 Communication Procedure Communication between the Commander and the de-icing crew will usually be achieved using a combination of printed forms and verbal communication. For treatments carried out after aeroplane doors are closed, use of flight interphone (headset) or VHF radio will usually be required. Use of hand signals is not recommended except for the final "all clear" signal. The procedural sequence as written below should be understood as a sample. Local procedures or detailed procedures established by the airline may differ.

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• Before fluid application starts, the Commander shall be requested to configure the aeroplane for deicing/anti-icing (surfaces, controls and systems, as per aeroplane type requirements) • The de-icing crew shall wait for confirmation that this has been completed before commencing the treatment. • For treatments carried out without the flight crew present, a suitably qualified individual shall be nominated by the aeroplane operator to confirm the treatment required and to confirm correct configuration of the aeroplane. Communication after De-icing/Anti-Icing Treatment An aeroplane shall not be dispatched for departure after a de-icing/anti-icing operation until the Commander has been notified of the type of de-icing/anti-icing operation performed (Anti-icing Code). The Anti-icing Code shall be provided by a qualified person at the completion of the treatment, indicating that the checked surfaces are free of ice, frost, snow, and slush, and in addition includes the necessary information to allow the Commander to estimate the holdover time to be expected under the prevailing weather conditions. Anti-Icing Codes The following information shall be recorded and be communicated to the Commander by referring to the last step of the procedure and in the sequence provided below: a Example: A de-icing/anti-icing procedure whose last step is the use of a mixture of 75% of a Type II fluid and 25% water, commencing at 13:35 local time on 20 February 2011, is reported and recorded as follows: TYPE II/75; 13:35; 20 Feb 2011; Complete name of anti-icing fluid; "Post de-icing/anti-icing check completed". Anti-Icing Code Content • the fluid Type; i.e. Type I, II, III, IV • the concentration of fluid within the fluid/water mixture, expressed as a percentage by volume (Note1) • the local time (hours:minutes), either - for a one-step de-icing / anti-icing: at the start of the treatment or - for a two-step de-icing / anti-icing: at the start of the second step (anti-icing) • the date (written: day, month, year) (Note 2) • the complete name of the anti-icing fluid (so called “brand name”) (Note3) • the statement "Post de-icing/anti-icing check completed” (Note 4) Note 1:

no requirement for Type I fluid

Note 2:

required for record keeping, optional for Commander notification

Note 3:

optional; for Type II and IV fluids only

Note 4:

For specific aircraft types, additional requirements exist e.g. special clear ice checks, such as tactile checks on wings. Additional confirmation for these checks is required

7.1.3 Types of Fluids 7.1.3.1 General De-icing fluid is normally applied heated in order to assure maximum efficiency. Type IV fluid gives a longer hold–over time than Type II fluid if 100% is applied. At certain stations, Type II fluid is handled in such a way that its properties do not fulfill the specification. In these cases, the product can still be used but the Hold-Over Time Table for Type I fluid has to be applied.

© Lido 2011

At some stations a dyed de-/anti-ice fluid might be sprayed. The dyed fluid is either a Type I or a Type IV fluid and assists ground personnel in conducting the final check. De-/anti-icing fluids do not provide any protection from contamination once the aircraft is airborne. Special Type Fluids:

Sheet 515543

LSY Standard (jetww)

Meteorology

250

MET

General Part

20-OCT-2011

MIL-A8243-D de-/anti-icing fluids are also classified in Type I and Type II fluids. However, these fluids are entirely different to ISO/SAE classified Type I and Type II fluid and do not fulfil the ISO/SAE specification. Type 1 1/2 and Type 3 might still be available at some aerodromes. However, these fluids are not covered by any international specification, e.g. type 3 are still to be found in Canada. The following Types are qualified and approved de/anti-icing fluids. 7.1.3.2 Type I Fluids • Clariant Safewing DG I • Clariant Safewing MP I • SPCA DE-825 • SPCA DE-910 • UCAR ADF Concentrate • UCAR ADF 50/50 (ready to use and shall not be diluted further) • UCAR ADF XL54 (ready to use and shall not be diluted further) • BASF Aerex 102 • Lyondell ACRO Plu 7.1.3.3 Type II Fluids • Kilfrost ABC-3 • Clariant Safewing MP II1951 • SPCA AD-104 (must be stored unheated) • SPCA 104/N • Octagon Forty Below (must not be used in 75/25 dilution) • UCAR AAF ULTRA (must be stored and applied unheated)

7.2 Hold-Over-Time (HOT) Policy 7.2.1 General The following procedures and tables are recommended by AEA (Association of European Airlines). For HOT given, latest edition has been used. In general different company policies may apply as well as different tables in terms of types of precipitation are published by FAA and / or Transport Canada. Hold–over protection is achieved by a layer of anti-icing fluid remaining on the protected aircraft surfaces for a period of time. With a one-step de-/anti-icing, the HOT begins at the commencement of the de-/anti-icing. With a two-step procedure, the HOT begins at the commencement of the second step, which is the anti-icing step. Generally, the low end of the range represents the estimated HOT in heavy conditions, the high end, the estimated HOT in light conditions. In heavy weather conditions, the HOT can even be shorter than the lower end of the range. The HOT, however, is not applicable in case of a hail or ice pellets precipitation or if a mixture of 25% antiicing fluid and 75% water is sprayed. It is the pilot’s decision to determine the HOT at a given concentration taking into account actual weather conditions.

CAUTION: De-icing/anti-icing fluids used during ground de-icing/anti-icing are not intended for - and do not provide - protection during flight. Sheet 523826

*523826* LSY Standard (jetww)

© Lido 2011

Note

MET

General Part

20-OCT-2011

260

Meteorology

7.2.1.1 Lowest Operational Use Temperature (LOUT): The Lowest Operational Use Temperature (LOUT) is the higher (warmer) of a) The lowest temperature at which the fluid meets the aerodynamic acceptance test for a given type (high speed or low speed) of aircraft; or b) The freezing point of the fluid plus the freezing point buffer of 10°C for Type I fluid and 7°C for Type II, III, or IV fluids. 7.2.2 One-Step- / Two-Step Guidelines 7.2.2.1 Type I Fluid Guideline for HOTs anticipated for ISO/SAE. Guidelines for the application of Type 1 Fluid/Water Mixtures (minimum concentrations) as a function of OAT One-Step Procedure

OAT

d

Two-Step Procedure

De-Icing/Anti-Icing

-3°C (27°F) and above

First Step: De-Icing

Second Step: Anti-Icing 1)

Heated water or a heated fluid/water mixture

Heated fluid/water mixture below with a freezing point of at least 10 °C (18 °F) below OAT -3°C (27°F) down to LOUT

Heated fluid/water mixture with a freezing point not more than 3°C (5°F) above OAT

Heated fluid/water mixture with a freezing point of at least 10 °C (18 °F) below OAT

Note 1:

Temperature of water of fluid/water mixtures shall be at least 60°C (140°F) at the nozzle. Upper temperature limit shall not exceed fluid and aircraft manufacturer's recommendations.

Note 2:

This table is applicable for the use of Type I Holdover Time guidelines. If holdover times are not required, a temperature of 60°C (140°F) at the nozzle is desirable.

Note 3:

To use Type I Holdover Time guidelines, at least 1 liter/m2 (about 2 Gals/100ft2) must be applied to the de-iced surfaces.

Caution: Wing skin temperatures may be lower than OAT. If this condition is identified, a stronger mix (more glycol) may need to be used to ensure a sufficient freeze point buffer. 1)

To be applied before first step fluid freezes, typically within 3 minutes.

7.2.2.2 Type II, III and IV Fluids Guideline for the application of Type II, Type III, and Type IV fluid/water mixtures (minimum concentrations) as a function of OAT Concentration of neat fluid/water mixture in vol% / vol%

© Lido 2011

OAT 1)

One-Step Procedure

Two-Step Procedure

De-Icing / AntiIcing

First step De-icing

Second Step AntiIcing 2)

-3°C (27°F) and above

50/50 heated 3) Type II, III, or IV fluid/water mixture

Heated water or a heated Type I, II, III or IV fluid/water mixture

50/50 Type II, III, or IV fluid/water mixture

below -3° to -14°C (27° to 7°F)

75/25 heated 3) Type II, III, 4) or IV fluid/water mixture

Heated Type I, II, III or IV fluid/water mixture with a freezing point not more than 3°C (5°F) above OAT

75/25 Type II, III 4), or IV fluid/water mixture

Sheet 523826

LSY Standard (jetww)

270

Meteorology

MET

General Part

22-SEP-2011

Concentration of neat fluid/water mixture in vol% / vol% One-Step Procedure

OAT 1)

below -14° to -25°C (7° to -13°F) below -25°C (-13°F)

De-Icing / AntiIcing

First step De-icing

Second Step AntiIcing 2)

100/0 heated 3) Type II, III 4) or IV

Heated Type, I, II, III or IV fluid/water mixture with a freezing point not more than 3°C (5°F) above OAT

100/0 Type II, III 4), or IV

Type II, III, or IV fluid may be used below -25°C (-13°F) provided that the freezing point of the fluid is at least 7°C ( 13°F) below OAT and the aerodynamic acceptance criteria are met (LOUT). Note: Type II/Type III/Type IV fluid may not be used below -25°C (-13°F) in active frost conditions Consider the use of Type I fluid/water mixture when Type II, III, or IV fluid cannot be used

1)

Fluids must only be used at temperatures above their LOUT

2)

to be applied before first step fluid freezes, typically within 3 minutes

3)

clean aircraft my be anit-iced with unheated fluid

4)

Type III fluid may be used below -10°C (14°F) provided that the freezing point of the fluid is at least 7°C (13°F) below OAT and that aerodynamic acceptance criteria are met (LOUT)

Note :

For heated fluid and fluid mixtures, a temperature not less than 60°C ( 140°F) at the nozzle is desirable. When the first step is performed using a fluid/water mix with a freezing point above OAT, the temperature at the nozzle shall be at least 60°C and at least 1 liter/m² (~2 Gals/100ft²) must be applied to the surfaces to be de-iced. Upper temperature limit shall not exceed fluid and aircraft manufacturer's recommendations

Caution 1:

Wing skin temperatures may be lower than OAT. If this condition is identified, it shall be verified if a stronger mix (more glycol) may need to be used to ensure a sufficient freeze point buffer. As fluid freezing may occur, 50/50 Type II, III, or IV fluid shall not be used for the anti-icing step of a cold soaked wing as indicated by frost or ice on the lower surface of the wing in the area of the fuel tank.

Caution 2:

An insufficient amount of anti-icing fluid, especially in the second step of a two step procedure, may cause a substantial loss of holdover time. This is particularly true when using a Type I fluid mixture for the first step (de-icing).

Caution 3:

Some fluids shall only be used undiluted. For some fluids the lowest operational use temperature may differ. For details refer to fluid manufacturer's documentation.

7.2.3 HOT Active Frost Type I, II, III, and IV Fluids Guidelines for holdover times anticipated for Type I, II, III, and IV fluids mixtures in active frost conditions as a function of OAT (Valid for metallic and composite surfaces) OAT

°C

-1 and above

°F

30 and above

Type II, III, and IV Fluid Concentration Neat Fluid Water Vol % / Vol %

below 30 to 27

Active frost Type I 1) 2)

Type II3) Type III3)

Type IV3)

100/0

8:00

2:00

12:00

75/25

5:00

1:00

5:00

3:00

0:30

3:00

100/0

8:00

2:00

12:00

75/25

5:00

1:00

5:00

50/50 below -1 to -3

Approximate Holdover Times under various weather conditions (hours : minutes)

0:35

Sheet 515545

*515545* LSY Standard (jetww)

© Lido 2011

a

Two-Step Procedure

MET

General Part

22-SEP-2011

280 Type II, III, and IV Fluid Concentration Neat Fluid Water Vol % / Vol %

OAT

°C

°F

below -1 to -3

below 30 to 27

below -3 to -10

Meteorology

below 27 to 14

Approximate Holdover Times under various weather conditions (hours : minutes) Active frost Type I

1) 2)

Type II3) Type III3)

Type IV3)

50/50

1:30

0:30

3:00

100/0

8:00

2:00

10:00

5:00

1:00

5:00

6:00

2:00

6:00

75/25

1:00

1:00

1:00

75/25 100/0

0:35

below -10 to -14

below 14 to 7

below -14 to -21

below 7 to -6

100/0

6:00

2:00

6:00

below -21 to -25

below -6 to -13

100/0

2:00

2:00

4:00

a

1)

Type I fluid / water mixture is selected so that freezing point of the mixture is at least 10°C (18°F) below the OAT

2)

May be used below -25°C (-13°F) provided the lowest operational use temperature (LOUT) of the fluid is respected

3)

These fluids may not be used below -25 °C (-13 °F) in active frost conditions.

7.2.4 Various Weather Conditions Type I Fluid Guidelines for holdover times anticipated for Time I fluid mixture as a function of weather condition and OAT (Valid for metallic and composite surfaces) Approximate Holdover Times under Various Weather Conditions (hours:minutes)

OAT 1)

© Lido 2011

a

Snow / Snow Grains/ Snow Pellets2)

Freezing Drizzle3)

Light Freezing Rain

Rain on Cold Soaked Wing 0:01-0:056)

°C

°F

Freezing Fog

-3 and above

27 and above

0:09-0:16

0:03-0:06

0:08-0:13

0:02-0:05

below -3 to -6

below 27 to 21

0:06-0:08

0:02-0:05

0:05-0:09

0:02-0:05

below -6 to -10

below 21 to 14

0:04-0:08

0:02-0:05

0:04-0:07

0:02-0:05

below -10

below 14

0:04-0:07

0:02-0:04

1) 2) 3) 4) 5) 6)

Other 4)5)

CAUTION: No Holdover time Guidelines exist

Ensure that the Lowest Operational Use Temperature (LOUT) is respected. In light "Rain and Snow" conditions use "Light Freezing Rain" holdover times If positive identification of "Freezing Drizzle" is not possible use "Light Freezing Rain" holdover times Other conditions are: Heavy snow, ice pellets, hail, moderate freezing rain, and heavy freezing rain For holdover times under active frost conditions see the separate frost table No holdover time guideline exists for this condition for O°C (32°F) and below

Type I Fluids / Water Mixture is selected so that the Freezing Point of the mixture is at least 10°C (18°F) below actual OAT

Sheet 515545

LSY Standard (jetww)

290

Meteorology CAUTION:

MET

General Part

22-SEP-2011

The time of protection will be shortened in heavy weather conditions. Heavy precipitaion rates or high moisture content, high wind velocity or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when the aircraft skin temperature is lower than OAT. Therefore, the indicated times should be used only in conjunction with a pre-takeoff check.

7.2.5 Various Weather Conditions Type II Fluid Guidelines for holdover times anticipated for Type II fluid mixtures as a function of weather conditions and OAT (Valid for metallic and composite surfaces) Type II Fluid Concentration Neat-Fluid/Water OAT1)

°C

Approximate Holdover Times under Various Weather Conditions (hours:minutes)

°F

c -3 and above

27 and above

c below 27 to 7

below below -14 to -25 7 to -13 or LOUT or LOUT a

Freezing Fog

Snow / Snow Grains / Snow Pellets2)

Freezing Drizzle3)

Light Freezing Rain

Rain on Cold Soaked Wing

100/0

0:35-1:30

0:20-0:45

0:30-0:55

0:15-0:30

0:08 -0:406)

75/25

0:25-1:00

0:15-0:30

0:20-0:45

0:10-0:25

0:05-0:25

50/50

0:15-0:30

0:05-0:15

0:08-0:15

0:05-0:09 0:10-0:20 0:080:157)

100/0

0:20-1:05

0:15-0:30

0:20-0:45

75/25

0:25-0:50

0:10-0:20

0:15-0:30

100/0

0:15-0:35

0:15-0:30

7)

7)

7)

O t h e r

4)5)

6)

CAUTION: No Holdover time guideline exist

1) Ensure that the Lowest Operational Use temperature (LOUT) is respected. Consider the use of Type I fluid when Type II fluid cannot be used. 2) In light "Rain and Snow" conditions use "Light Freezing Rain" holdover times 3) If positive identification of "Freezing Drizzle" is not possible use "Light Freezing Rain" holdover times 4) Other conditions are: Heavy snow, ice pellets, moderate and heavy freezing rain, hail 5) For holdover times under active frost conditions see the separate frost table 6) No holdover time guidelines exist for this condition for 0°C (32°F) and below 7) No holdover time guidelines exist for this condition below -10°C (14°F)

CAUTION:

The time of protection will be shortened in heavy weather conditions. Heavy precipitaion rates or moisture content, high wind velocity, or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when the aircraft skin temperature is lower than OAT. Therefore, the indicated times should be used only in conjunction with a pre-takeoff check.

© Lido 2011

c

below -3 to -14

Vol %/ Vol %

Sheet 515546

*515546* LSY Standard (jetww)

MET

General Part

22-SEP-2011

300

Meteorology

7.2.6 Various Weather Conditions Type III fluid Guideline for holdover times anticipated for Type III fluid mixtures as a function of weather conditions and OAT (Valid for metallic and composite surfaces) Type III Fluid Concentration Neat-Fluid/Water OAT1)

°C

-3 and above

a

Approximate Holdover Times under Various Weather Conditions (hours:minutes)

°F

27 and above

Vol %/ Vol %

Freezing Fog

Snow / Snow Grains / Snow Pellets2)

Freezing Drizzle3)

Light Freezing Rain

Rain on Cold Soaked Wing

100/0

0:20-0:40

0:10-0:20

0:10-0:20

0:08-0:10

0:06-0:20

75/25

0:15-0:30

0:08-0:15

0:08-0:15

0:06-0:10

0:02-0:10

50/50

0:10-0:20

0:04-0:08

0:05-0:09

0:04-0:06

below -3 to -10

below 27 to 14

100/0

0:20-0:40

0:09-0:15

0:10-0:20

0:08-0:10

75/25

0:15-0:30

0:07-0:10

0:09-0:12

0:06-0:09

below -10

below 14

100/0

0:20-0:40

0:08-0:15

O t h e r

4)5)

6)

6)

CAUTION: No holdover time guideline exist

1) Ensure that the Lowest Operational Use Temperature (LOUT) is respected. Consider the use of Type I fluid when Type III fluid cannot be used. 2) In light "Rain and Snow" consider use "Light Freezing Rain" holdover times 3) If positive identification of "Freezing Drizzle" is not possible use "Light Freezing Rain" holdover times 4) Other conditions are: Heavy snow, ice pellets, moderate, and heavy freezing rain, hail 5) For holdover times under active frost conditions see the separate frost table 6) No holdover time guidelines exist for this condition for 0°C (32°F) and below

© Lido 2011

CAUTION:

The time of protection will be shortened in heavy weather conditions. Heavy precipitaion rates or moisture content, high wind velocity, or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when the aircraft skin temperature is lower than OAT. Therefore, the indicated times should be used only in conjunction with a pre-takeoff check.

Sheet 515546

LSY Standard (jetww)

310

Meteorology

MET

General Part

22-SEP-2011

7.2.7 Various Weather Conditions Type IV fluid Guidelines for holdover times anticipated for Type IV fluid mixtures as a function of weather conditions and OAT (Valid for metallic and composite surfaces) SAE Type IV Fluid Concentration Neat-Fluid/Water OAT1)

°C

Approximate Holdover Times under Various Weather Conditions (hours : minutes)

°F

c 27 and above

c c c

below -3 to -14

below a -14 to -25 or LOUT a

below 27 to 7 below 7 to -13 or LOUT

Freezing Fog

Snow / Snow Grains / Snow Pellets2)

Freezing Drizzle 3)

Light Freezing Rain

Rain on Cold Soaked Wing

4)5)

100/0

1:20-3:10

0:35-1:15

0:45-1:30

0:25-0:40

0:10-1:15

75/25

1:00-1:45

0:30-0:55

0:35-1:05

0:25-0:35

0:09-0:50

50/50

0:15-0:35

0:07-0:15

0:10-0:20

0:07-0:10

100/0

0:20-1:20

0:25-0:50

0:20-1:00

0:10-0:25

0:15-1:00

0:10-0:25

75/25

0:25-0:50

0:20-0:35

100/0

0:15-0:40

0:15-0:30

O t h e r

7)

7)

7)

7)

6)

6)

CAUTION: No Holdover time Guideline exist

1) Ensure that the Lowest Operational Use Temperature (LOUT) is respected. Consider the use of Type I fluid when Type IV fluid cannot be used 2) In light "Rain and Snow" consider use "Light Freezing Rain" holdover times 3) If positive identification of "Freezing Drizzle" is not possible use "Light Freezing Rain" holdover times 4) Other conditions are: Heavy snow, ice pellets, moderate and heavy freezing rain, hail 5) For holdover times under active frost conditions see the separate frost table 6) No holdover time guidelines exist for this condition for 0°C (32°F) and below 7) No holdover time guidelines exist for this condition below -10°C (14°F)

CAUTION:

The time of protection will be shortened in heavy weather conditions. Heavy precipitaion rates or moisture content, high wind velocity or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when the aircraft skin temperature is lower than OAT. Therefore, the indicated times should be used only in conjunction with a pre-takeoff check.

© Lido 2011

c

-3 and above

Vol %/ Vol %

Sheet 515547

*515547* LSY Standard (jetww)

MET

General Part

22-SEP-2011

320

Meteorology

7.3 Adverse Runway Condition 7.3.1 Dissemination of RWY State Information SNOWTAMs and RWY reports are only provided for winter conditions and not for other hazardous RWY conditions e.g. RWY slippery when wet or combined with dust. Observations and measurements are not made at routine intervals. Information on RWY state and braking conditions as contained in SNOWTAM are available from ATC and are usually broadcasted on ATIS. When giving landing information, the thirds of the RWY are referred to as first, second, and third part. Other information e.g. state of TWY, apron etc. are added. 7.3.2 SNOWTAM The SNOWTAM is a specialized NOTAM notifying the presence of hazardous RWY condition due to snow, ice, etc. by using a specified ICAO format. It is available on the NOTAM or at the AIS office as soon as the presence of contamination is considered to be operationally significant. The closure of a RWY for clearance and the subsequent reopening may be notified by a NOTAM. ⇒

Meteorology General Information

8.5 SNOWTAM Decoding

7.3.2.1 Issue/Validity of SNOWTAMs A new SNOWTAM should normally be issued every 6 HRs. For aerodromes with no night operation or closed at night, a new SNOWTAM should be promulgated 2 HRs before the aerodrome is reopened for operation. The validity of SNOWTAMs is maximum 24 HRs. If the validity expires, a new observation, measurement should be made even if conditions have not changed and a new SNOWTAM should be issued. 7.3.3 METAR Runway Report RWY reports are provided in the abbreviated form of 8-figure groups appended to weather reports (METAR). These reports are derived from the SNOWTAM. For obvious reasons e.g. traffic density the half hourly rhythm of METARs is not practicable for RWY condition observations. Thus a repetition of the previous RWY report may mean that no significant change has occurred. If an aerodrome is closed due to snow or removal of snow and ice, the term SNOCLO may replace the 8-figure code group. ⇒

Meteorology General Information

8.1.1 Runway Report Decoding

7.3.4 Issue/Validity of RWY Reports. RWY reports are based on the same observation/measurements as the SNOWTAM and are repeated with every subsequent weather report until a new RWY report is made. 7.3.4.1 Assessment of Deposit Water on the RWY Whenever water is present on RWYs description of the conditions on the center half of the RWY should be made using the following terms: • DAMP - the surface shows a change of color due to moisture. • WET - the surface is soaked but there is no standing water. • WATER PATCHES - significant patches of standing water are visible. • STANDING WATER - standing water of significant depth and area which affects significantly the braking action (aquaplaning). • FLOODED - extensive standing water is visible during heavy rainfall. Snow and Slush on the RWY • DRY SNOW - snow which can be blown if loose or, if compacted by hand, will fall apart again upon release. © Lido 2011

• WET SNOW - snow which, if compacted by hand will stick together and tend to form a snowball. • SLUSH - water saturated snow which with a heel and toe slap down motion against the ground will be displaced with a splatter. Sheet 515547

LSY Standard (jetww)

330

Meteorology

MET

General Part

12-MAY-2011

• COMPACTED SNOW - snow which has been compressed into a solid mass that resists further compression and will hold together or break up into lumps if picked up. Combination of Ice, Snow, and Standing Water Such combinations, especially when rain sleet or snow is falling, may have a rather transparent appearance due to their high water / ice content, shall be considered as slush. Accuracy of Depth of Deposit When dry or wet snow or slush is present on a RWY, an assessment of the mean depth should be made to an accuracy of approximately 2CM for dry snow, 1CM for wet snow and 3MM for slush. The depth of deposit of compacted / solid contaminants such as ice, compacted snow or frozen ruts or ridges which do not cause a drag (retarding rolling) is not considered to be operationally significant and needs not to be assessed and reported. The depth of standing water is very difficult to assess. Hence it is often reported as “not measurable”. ⇒

Meteorology General Information

8.1.1 Runway Report Decoding

Assessment of Extent of Runway Coverage The extent of the coverage of the RWY reported in percent is the best possible estimate but shall not be understood to be an accurate measurement. Assessment of Braking Condition Operation considerations require reliable and uniform reports on braking conditions whenever RWYs are contaminated and subsequent updating when conditions significantly change. The reported Friction Coefficient (FC) is a relative measure for the achievable friction of the tire to surface interface of a braked wheel and should be the maximum which occurs when a wheel is slipping but still rolling. Measurements should be made at a distance of 3m or the distance from the centerline where most operations take place. The reported Braking Action (BA) may reflect the FC converted to BA as well as subjective pilot reports or assessments by empirical methods. Therefore, for operation applications the FC is generally preferable to the BA which often lacks a proper standardized reference basis. If BA is reported it is recommended to request the FC if measured or, if the BA stems from pilot reports, to be informed on the aircraft type involved. The FC and especially the BA should not be taken as absolute due to the many methods of assessment used and the different variables such as aircraft weight, speed, landing technique, braking performance, tires, and undercarriage characteristics, etc. 7.3.4.2 Measuring Devices All types of measuring equipment do not enable measurements with satisfactory reliability in aquaplaning conditions (standing water, slush, and wet snow) or if more than a thin layer of loose snow is present. In such cases the braking conditions should be reported as “unreliable”. When considering Friction Coefficients (FC) of wet RWYs, especially with smooth surface, it should be noted that the friction may drop markedly with increasing speed. Equipment Permitting Continuous Measurement. e.g: • Surface Friction Tester (SFT) • Skiddometer SKH/SKL (high/low pressure) • Mu-Meter (MUM) • Grip Tester (GRT) • RWY Friction Tester (RFT) © Lido 2011

…can be used for friction values on compacted snow and ice covered RWYs. Decelerometers, e.g.: Sheet 471336

*471336* LSY Standard (jetww)

MET

General Part

12-MAY-2011

340 •

Meteorology

Tapley Meter (TAP)

• Dynometer …may be used on certain surface condition (compacted snow, ice, and very thin layers of dry snow). Decelerometers should not be used in loose snow or slush. Subjective methods permitting assessment of Braking Action (BA) only: Truck, car or pilot‘s report. The reliability of such reports is questionable. 7.3.4.3 Relationship Between Friction Coefficient (FC) and Braking Action (BA) The table below was developed by ICAO based on measurements on ice and compacted snow. It states the relationship between FC and BA. It should not be taken to be absolute values and applicable in all conditions and should not be used to convert BA into FC. The relation between FC and empirically assessed BA is rather loose due to the lack of a proper standardized reference basis referring e.g. to the type of vehicle and its tires used, the pilot‘s experience, the aircraft type, and its performance in such conditions. Therefore the table should not be used to convert BA into FC. For operational purposes: Friction Coefficient

Estimated Braking Action

0.40 and above

GOOD

0.39 - 0.36

MEDIUM TO GOOD

0.35 - 0.30

MEDIUM

0.29 - 0.26

MEDIUM TO POOR

0.25 and below

POOR

Different relationships between Friction Coefficient and Braking Action may be applied by country rules and regulations, e. g. Canada and Russia. 7.3.4.4 Differences from ICAO Standard I.e. Canada and Russia apply procedures different from ICAO Standard. For further details refer to respective RSIs and CRARs.

8 Decoding of Meteorological Data 8.1 TAF & METAR Decoding (ICAO) Italic information are for U.S. / Canada only. ⇒

North America MET

TAF & TREND Examples

3.1 USA / CANADA METAR / TAF. METAR, SPECI Examples

Decoding METAR / TREND, SPECI & TAF

METAR, SPECI METAR/SPECI COR

Data type designator: TAF or TAF amended/corrected. METAR, SPECI, or METAR/SPECI corrected

EDDF

EDDF

Aerodrome: ICAO 4-letter location indicator

160900Z

160950Z

Date and time: TAF=issue of forecast, METAR/SPECO = actual time of observation (day of the month and time (HRs and MIN)

© Lido 2011

TAF TAF AMD/COR

Sheet 471336

LSY Standard (jetww)

350

Meteorology TAF & TREND Examples

METAR, SPECI Examples

MET

General Part

12-MAY-2011

Decoding METAR / TREND, SPECI & TAF

Auto

Validity of TAF (Days and period of the validity of the forecast in UTC). Validity of TREND: 2 HRs (Australia 3 HRs) from observation time METAR/SPECI: AUTO if report from fully automated STN

19018KT VRB03KMH 27016G30KT 140P99KT

35006KMH 000000KT 11027G45KT 340V050 140P199KMH

Mean wind and gusts in degrees true and KT or KMH VRB = variable; 00000 = calm G = gusts, maximum wind during the last 10 MIN V = fluctuating (variable)wind direction P = more than 100KT or 199KMH

CAVOK

CAVOK

CAVOK: 1) VIS ≥ 10km; 2) No clouds below 5000ft or highest MS, no CBs/TCUs, 3) no significant weather as given under Forecast/present weather (details shown at the end of this table)

0350, 7000 9000, 9999 4SM, 11/2SM

0050, 1600 8000, 9999 13/8SM, P6SM 0800NE 7000NDV

Visibility: TAF = prevailing VIS; METAR/SPECI prevailing VIS or MIN VIS (in meters: 0000 = <50m, 9999 ≥ 10km)$ In SM and fraction thereof: 1/16SM = < 100m, P = more Minimum VIS and direction NDV (from automated STN): No directional variation can be given.

R32/0275 R24R/1200ft R09L/0375U R01C/P1500 R11/0175V0300 R19R/M0100 R15/0300ft/D

Runway Visual Range (touchdown zone, in M) In feet: M150 = < 50m, P5000 = > 1600m R plus Runway designator: L = Left, R = Right, C = Center Qualifier: M = less than …., P = more than …., Fluctuating RVR V: maximum and minimum RVR Recent tendency: U = Up, D = Down, N = no change Recent tendency in Canada only R15/0300ft/D

+RA, SN, FG, -SHSN, HZ NSW

VCSH, FZRA, +SHRASN -SN

Forecast / present weather in 2-letter ABB (see below) Intensity: -=light, no sign = moderate, + = heavy NSW = cessation of sign. Weather given in preceding part of TAF

VV000, VV002 VV001, VV///

VV000, VV300 VV/// Vertical visibility VV in hundreds of feet: VV000 < 100 VV001 <200, VV/// = not available, sky obscured

OVC000 SKC SCT025 OVC008CB NSC

SKC BKN003 FEW012 BKN008CB NSC NCD

Clouds base in hundreds of feet: 000 < 100, 001 < 200 Sky cover: FEW (1 to 2 oktas), SCT = scattered (3 to 4 oktas), BKN = broken (5 to 7 oktas), OVC = overcast (8 oktas); Cloud type = only TCU and CB given SKC = no clouds, no restriction on VV, CAVOK not appropriate NSC = no clouds of OPS-significance, no CBs, no restrictions on VV, CAVOK and SKC not appropriate NCD (from automated STN) = no clouds detected

01/M02, 23/15

Temperature / dewpoint in degrees Celsius, M if < 0° C

Q0997, Q1038 A2991, A3027

QNH / altimeter setting Q in hectopascal hPa A in 1/100 of inches mercury Hg

© Lido 2011

0606/1624 0812/0918

Sheet 471337

*471337* LSY Standard (jetww)

MET

General Part

12-MAY-2011

360 TAF & TREND Examples

METAR, SPECI Examples REFZDZ, RERA RETSRA, RESN WS RWY 16 99421594 SNOCLO

Decoding METAR / TREND, SPECI & TAF Supplementary Information Recent Weather (in period since last report or last hour whichever is shorter, cessation also in TREND forecast). Indicator RE Windshear (plain language or coded form) Non – convective WS: Wind at a height in hundreds of feet Remark section in coded or plain language, e. g. tornado RWY-Report (8 figure/character group) For decoding refer to RM MET, Decoding of RWY Report Optional groups in TAF / Remarks in METAR MAX/MIN Temperature forecast T in °Celsius and day/time MIN Temperature (M if < 0° C)

TX21/1208Z TN09/1705Z TNM02/0503Z BECMG 1414/1416 TEMPO 1421/1501 PROB40 1203/1205 FM121800

Meteorology

BECMG TEMPO

PROB40 +SS

TREND only BECMG/TEMPO FM1030 TL1700 BECMG AT1800 TEMPO FM1030 TL1700

Change groups in TAF and METAR / TREND TAF: Indicator and time groups in UTC. TREND: Indicator, validity for next 2 HRs from observation time. BECMG = becoming change to new prevailing condition. TEMPO = temporary change (< 1 hour) during valid period. PROB30 / 40 = probability in % FMddhrmn = beginning of a new self-contained part of TAF. NOSIG = no significant change in wind/VIS/weather/clouds USA: PROB40 is only used, PROB TEMPO is not used.

PROB40 TS RMK FM140200 MOD TURB BLW 5000ft

RMK CI1 SLP287

Remarks in METAR/TAF Remarks can be disregarded. The contents is only for local purposes. Encoding is not internationally agreed.

Forecast / Present Weather Intensity: No symbol = moderate; Symbol “-” = light; Symbol “+” = heavy intensity/condition. Note

On ACARS message the “+” sign will be coded as “.”, e.g. heavy rain will be coded .RA

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Weather Types: In case of different precipitation, the dominant type is given first. The following abbreviations or suitable combinations thereof are used: BC = patches of fog

MI = shallow

Sheet 471337

LSY Standard (jetww)

370

Meteorology BL = blowing …

PL = ice pellets

BR = mist

PO = dust devils, dust/sand whirls

DR = low drifting

PR = partial; covering part of aerodrome

DS = duststorm

RA = rain

DU = widespread dust

RE = recent

DZ = drizzle

SA = sand

FC = funnel clouds

SG = snow grains

FG = fog

SH = showers of …

FU = smoke

SN = snow

c FZ = freezing GR = hail (ø ≥ 5MM)

SQ = squalls SS = sandstorm

GS = small hail, snow pellets

TS = thunderstorm

HZ = haze

VA = volcanic ash

IC = ice crystals

VC = between approx 8 and 16km of aerodrome reference point

8.1.1 Runway Report Decoding Figures

c

Examples

RWY letter R and designator 01 ... 36 followed by /

R26/491529

3rd figure

type of deposit

R26/491529

4th figure

extent of contamination / coverage

R26/491529

5th and 6th figure

depth of deposit in MM

R26/491529

7th and 8th figure

braking conditions (FC or BA)

R26/491529

Parallel RWYs:

are identifed as follows : R = right, C= center L= left

R26R/190095

The figure 88:

the conditions apply for all RWYs of an AD.

R88/290195

The figure 99:

Indicates that the previous report is repeated.

R99/150068

0 = clear and dry

4 = dry snow

8 = compact or rolled snow

R26/820393

1 = damp 3rd figure Type of deposit (the most significant one 2 = wet / is reported) water patches

5 = wet snow

9 = frozen ruts or ridges

R26/551092

1st & 2nd figure RWY designator

3 = rime or frost

6 = slush

R26/691020

7 = ice

R26/390040

/ = not reported, e.g. due to RWY clearance in progress

R26//50094 © Lido 2011

c

Explanation

1st and 2nd figure Information on RWY conditions by 8-figure groups appended to METAR.

MET

General Part

16-JUN-2011

Sheet 486423

*486423* LSY Standard (jetww)

MET

General Part

16-JUN-2011

380 Figures c

Meteorology

Explanation

Examples

1 = ≤10% of 5 = 26% - 50% RWY

4th figure Extent of contamination / 2 = 11% coverage in % 25%

R26/910055 R26/790299

9 = ≥51%

/ = not reported, e.g. due to RWY clearance in progress figures:

c

5th & 6th figure Depth of deposit in mm

special figures:

Friction coefficient: d c

7th & 8th figure Braking conditions FC or BA (lowest value of the measurement)

Braking Action:

R26//90599 R26/790002

00 = less than 1MM

R26/350740

01 - 90 thickness in MM 92 = 10CM

93 = 15CM

94 = 20CM

R26/4994//

95 = 25CM

96 = 30CM

97 = 35CM

R26/4997//

98 = 40CM

R26/4998//

99 = RWY closed due to contamination or clearance

R26/499999

// = depths of deposit not of significance (e.g. ice) or not measurable (e.g. RWY wet)

R26/21//95

values from “01 to 90”, e.g. 34 = FC 0.34

R26/650334

91 = poor

92 = medium to poor

R26/891091

93 = medium

94 = medium to good

R26/390292

95 = good

// BA not reported and/or RWY not operational

R26/110095

99 = unreliable, FC or BA, where the measurement is not satisfactory reliable. This may be the case, when a RWY is contaminated (wet snow, slush, or loose snow)

R26/652099

Relationship between FC and BA: refer to RM MET, Decoding of SNOWTAM, code H Rxx///99//

R26///99//

RWY clearing in progress

contaminated but reports are not Rxx/ / / / / / / RWY updated (night curfew) Special cases

R26///////

Rxx/CLRD//

contamination conditions are no longer applicable

R26/CLRD//

R/SNOCLO

all RWYs closed due to snow, ice etc and/or clearance in progress

R/SNOCLO

8.2 Military (NATO) Color Coded Weather Conditions (When operational/diverting or emergency color coded weather condition may be used)

© Lido 2011

Color

Ceiling (5/8)

Surface visibility

BLUE +

BLU+

No ceiling below 20000ft GND

BLUE

BLU

2500ft AGL

WHITE

WHT

1500ft AGL

5km (2.7NM / 3.1SM)

GREEN

GRN

700ft AGL

3.7km (2NM / 2.3SM)

8km (4.3NM / 5SM)

Sheet 486423

LSY Standard (jetww)

390

Meteorology Color

Ceiling (5/8)

YELLOW 1 *

YLO

YELLOW 2 *

MET

General Part

12-MAY-2011

Surface visibility

500ft AGL

2.5km (1.3NM / 1.5SM)

300ft AGL

1.6km (0.9NM / 1SM)

AMBER

AMB

200ft AGL

0.8km (0.4NM / 0.5SM)

RED

RED

Below 200ft AGL

< 0.8km (0.4NM / 0.5SM)

BLACK **

BLACK

AD not usable for other reasons than ceiling and / or visibility minima

Notes: *YELLOW=YELLOW 2 **BLACK, when used, will precede the current weather color code

8.3 SIGMET / AIRMET - (OPMET Data Bank Designator) 2-letter codes used to store and retrieve information in data banks: 2-Letter Code FA FC FK FT FV SA SP WA WC WS WV

Meaning GAMET TAF less than 12HRs Tropical Cyclone Advisory (TCA) TAF up to 30HRs Volcanic Ash Advisory (VAA) METAR SPECI AIRMET SIGMET: tropical Cyclone SIGMET SIGMET: Volcanic Ash

8.4 ASHTAM Decoding Alert Color Code Level of alert color code

Status of activity of volcano

ORANGE ALERT

Volcanic eruption in progress but ash plume/cloud not reaching nor expected to reach FL250 or Volcano dangerous, eruption likely but ash plume/cloud not expected to reach FL250.

© Lido 2011

RED ALERT

Volcanic eruption in progress. Ash plume/cloud reported above FL250 or Volcano dangerous, eruption likely, with ash plume/cloud expected to rise above FL250.

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MET

General Part

12-MAY-2011

400 Level of alert color code

Meteorology Status of activity of volcano

YELLOW ALERT

Volcano known to be active from time to time and volcanic activity has recently increased significantly, volcano not currently considered dangerous but caution should be exercised or Volcano dangerous, eruption likely but ash plume/cloud not expected to reach FL250.

GREEN ALERT

Volcanic activity considered to have ceased and volcano reverted to its normal state.

Decoding of ASHTAMS A) CENTRAL AMERICAN

Flight Information Region affected, plain language equivalent of the location indicator given in the abbreviated heading.

B) 0506270730

Date and time (UTC) of the first eruption

C) VOLCAN SAN CRISTOBAL 14004-02

Name of volcano, and number of volcano

D) 124211N0870024W

Latitude/Longitude of the volcano in whole degrees or radial and distance of volcano from NAVAID.

E) YELLOW ALERT

Color Code for Level of alert indicating volcanic activity, including any previous level of color code

F) SFC/11000ft

the horizontal extent and base/top of the ash cloud using latitude/longitude (in whole degrees) and altitudes in thousands of meters (feet) and/or radial and distance from source volcano. Information initially may be based only on special air-report, but subsequent information may be more detailed based on advice from the responsible meteorological watch office and/or volcanic ash advisory center.

G) E/S

Forecast direction of movement of the ash cloud at selected levels based on advise from the responsible meteorological watch office and/or volcanic ash advisory center.

H) VOR/DME MGA A317 TUKOR CNL

Air routes and portions of air routes and flight levels affected, or expected to become affected.

I) VOR/DME MGA A317 TUKOR RTE AVBL. ALT RTE MGA VOR/DME A502 BERTA GABOS A317. VOR/DME/CAT/AVBL

Closure of airspace, air routes or portions of air routes, and availability of alternative routes

J) INSTITUTO NATIONAL DE ESTUDIOS TERRITORIALES. DPTO. DE SISMOLOGIA

Source of the information, e.g. “special air report” or “vulcanological agency”, etc.

K) GNE AVIATION CTN WIND 60KMH E/SE FM VOLCANO

Any operationally significant information additional to the foregoing in plain language.

8.5 SNOWTAM Decoding

© Lido 2011

Information on runways, taxiways and apron conditions appended to aerodrome information in the NOTAM, coded from items «A to T». Example of Completed SNOWTAM Format GG EHAMZQZX EDDFZQZX EKCHZQZX 070645 LSZHYNYX

Sheet 471339

LSY Standard (jetww)

410

Meteorology SWLS0149 LSZH 11070620 (SNOWTAM 0149 A) LSZH B) 11070620

R) NO Item Header

S)11070920

C) 02 C) 09 C) 12 T) DEICING)

MET

General Part

21-JUL-2011

D) ... P) D) ... P) D) ... P)

Explanation

Example(s)

SNOWTAM-Designator “SW” + 2-letter ICAO state designator + SNOWTAM 4-figure serial number, SWEH0087 location indicator of AD, month, day, and time of OBS. Data indicator: SNOWTAM and serial numbers.

SNOWTAM S087

A)

Aerodrome location indicator (4-letter ICAO)

A) EHAM

B)

Date / Time: Month / day / time in UTC of OBS

B) 12310520

C)

RWY designators: In case of parallel RWYs “L” or “R” is added.

C) 27R

D)

Cleared RWY length, if less than published length: in meters

D) 3100

E)

Cleared RWY width if less than published width: In meters, if offset from CL “L” or “R” is added.

E) 40L

F)

Deposits over total RWY length: Observed on each third of the RWY, starting from THR having the lower RWY designation number

F) 78 / 49 / 4

nil = clear and dry 1 = damp 2 = wet or water patches 3 = rime or frost covered 4 = dry snow

5 = wet snow 6 = slush 7 = ice 8 = compacted or rolled snow 9 = frozen ruts or ridges

If more than one type of deposit is present a combination of these numbers are reported. Drifts, depth of deposit, or other significant characteristics of deposits may be reported under item T. Mean depth: In MM for each third of total RWY length (XX if not measurable or operationally not significant

H)

Friction measurements on each third of RWY and device: H) 34 /27 /18 • When quoting a measured coefficient, use the observed two figures, SFL H) 66 /63 /72 followed by the abbreviation of the measuring device. TAP • When quoting an estimate, use single digit value 9 = unreliable, when SFC COND or the AVBL measuring device are not permitting a H) 15 /20/08 SKH H) 1 / 1 /9 reliable measurement. H) 3 / 2 / 1 H) 5 / 3 / 5 Code Friction Breaking Action (BA) Russian Coefficient (FC) (Normative) Friction Coefficient (equivalent) 1

0.25 and below

= poor

0.31-0.34

2

0.26-0.29

= medium to poor

0.35-0.36

3

0.30-0.35

= medium

0.37-0.39

4

0.36-0.39

= medium to good

0.40-0.41

5

≥ 0.40

= good

G) XX / 3 / 10

≥ 0.42

© Lido 2011

a

G)

Sheet 501107

*501107* LSY Standard (jetww)

MET

General Part

21-JUL-2011

420 Item c

Meteorology

Explanation

Example(s) See Note 2

H) U.S. = MU-values CANADA = CRFI

Type of measuring equipment (H = high press. tire, L = low press. tire): BRD = Brake/Dynometer SFH = Surface friction tester H SFL = Surface friction tester L GRT = Grip tester

SKH = Skiddometer H MUM = Mu-meter SKL = Skiddometer L RFT = RWY friction tester TAP = Tapley meter

H) 34 /27 /18 SFL H) 66 /63 /72 TAP H) 15 /20/08 SKH H) 1 / 1 /9 H) 3 / 2 / 1 H) 5 / 3 / 5

J)

Critical snowbanks: If present, insert height (CM)/distance from edge of RWY (M) followed by “L”, “R”, or “LR” if applicable.

J) R80 / 6 / l65 / 5 J) LR120 / 8

K)

RWY lights: If obscured, insert “YES”, followed by “L”, “R”, or “LR” if applicable

K) YES R k) YES LR

L)

Further clearance: If planned, insert length (M)/width (M) to be cleared or if to full dimension, insert “TOTAL”.

L) 3700 / 40 L) total

M)

Further clearance expected to be completed by: ...... UTC

M) 0615

N)

Taxiway: See code F or if no appropriate TWY is available, insert “NO”.

N) 478 N) no

P)

Taxiway snowbanks: If more than 60CM insert “YES” followed by DIST in meters.

P) YES 4

R)

Apron: See code F, if apron is unusable insert “NO”

R) 56 R) no

S)

Next planned OBS/measurement is for: month/day/hour in UTC

S) 01010515

T)

Plain language remarks - on any operationally significant INFO including: Length and location of part of RWY uncleared (item D) and extent of RWY contamination (item F) for each third of RWY (if appropriate) according to the following scale: “10%” ≤ 10% contaminated “25%” = 11-25% contaminated “50%” = 26-50% contaminated “100%” = 51-100% contaminated

T) RW26 LAST 300M NOT CLEARED / COVERED WITH 10CM DRY SNOW. RW26 50% / 25% /100%

a Note 1:

Codes may be dropped completely when not applicable. • INFO on other RWYs, repeat from C to P. • A new SNOWTAM must be issued whenever there is a significant change in conditions (check serial number). • The maximum validity of a SNOWTAM is 24 HR from the time of observation. • Temporary closure of an AD for removal of contamination and its subsequent reopening are additionally notified by a separate NOTAM. ⇒ ⇒

Europe MET

3.4 Russian (Normative) Friction Coefficient 3.3 Russian (Normative) Friction Coefficient

Middle East / Asia MET

© Lido 2011

a Note 2: a

Sheet 501107

LSY Standard (jetww)