SAWS Workshop IISAWS Workshop II

October 2008October 2008Jamie GudmestadJamie Gudmestad

- Meteorologist Intern- Meteorologist InternWFO Midland, TXWFO Midland, TX

- Air Force Reserve- Air Force ReserveWeather ForecasterWeather Forecaster

Shaw AFB, SCShaw AFB, SC

AIRCRAFT ICINGAIRCRAFT ICING

Aviation Safety Foundation

My employment

Full time – Meteorologist WFO Midland

Part time – Forecaster for various areas in the Middle EastWikipedia

Content of this presentation

- Why icing is SO important to aviation- Where and when icing commonly occurs- The types of icing- Type of aircraft most susceptible to icing- TAFs and other products- Future icing detection- Where more information can be found

The National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the United States, its territories, adjacent waters and ocean areas, for the protection of life and property.

www.airport-technology.com

"An estimated 819 people died in accidents related to in-flight icing between 1982 and 2000."

Study by the National Transportation Safety Board

Over 40 people/year

American Eagle 4184 October 31, 1994

Roselawn, Indiana

Crashed after circling in icy weather

killed all 68 on board

Airlines.net

Air Florida Flight 90 January 13, 1992

Washington DC

Aircraft was De-iced, then sat on the runway

killed all 78 on board

Airdisaster.com

A Cessna 208B CaravanNovember 8, 2002

Parks, Arizona

Aircraft was in route from Las Vegas, NV on its way to Midland, TX

Moderate mixed icing

aironline.com/wikipedia

NormalNormal

IcedIced

Hanley Innovations: Airfoil Icing & Microtab Study

Airfoil

Icing of other aircraft parts

AOPA Aviation Safety Foundation

Icy Runways

Webshots.com

Near Saturated environment

Favorable Atmospheric Conditions for Icing:

Temperature Dew point Depression Approx. RH 0° to -7°C (32 to 18°F) less than 2°C (<3.6°F) 85% -8 to -15°C (17 to 5°F) less than 3°C (<5.4°F) 80% -16 to -22°C (4 to -8°F) less than 4°C (<7.2°F) 75%

Key Ingredient

AFWA TN 98-002

Winter

Map from the Air Safety Foundation (AOPA)

- Icing is more likely & more severe in clouds located near moisture sources & over mountainous regions

Mountains

University Corporation for Atmospheric Research (COMET)

Fronts

University Corporation for Atmospheric Research (COMET)

Fronts

University Corporation for Atmospheric Research (COMET)

Clouds

HIGHHIGH 0° to -20°C 0° to -15°C 0 °C & below 0° to -20°C 0° to -15°C 0 °C & below (32° to -4°F) (32° to 5°F) (32°F & below) (32° to -4°F) (32° to 5°F) (32°F & below) MED -20° to -40°C -15° to -30°C MED -20° to -40°C -15° to -30°C (-4° to -40°F) (-5° to -22°F)(-4° to -40°F) (-5° to -22°F)LOW < -40°C < -30°CLOW < -40°C < -30°C (< -40°F) (< -22°F)(< -40°F) (< -22°F)

Icing Risk/Type of CloudsCumulus Stratiform Rain & Drizzle

AOPA Aviation Safety Foundation

Vertical Displacement increases Icing

AFWA TN 98-002

Icing Severity definitionsTrace – “when the rate of ice accumulation is just slightly greater than the rate of loss due to sublimation”

Light – “the rate of ice accumulation may create a problem if the aircraft remains in this environment for one hour or more”

Moderate – “when the rate of ice accumulation is so great that even a short encounter can become hazardous”

Severe – “whenever the rate of ice accumulation is such that deicing or anti-icing equipment cannot control or reduce the hazard”

University Corporation for Atmospheric Research (COMET)

Droplet Size

- Cloud droplets – usually 40 microns or less- Supercooled liquid droplets (SLD) are 40 – 200 microns; MOST SIGNIFICANT to Aircraft Icing - SLD most often includes freezing rain & drizzle

University Corporation for Atmospheric Research (COMET) Fotosearch.com

University Corporation for Atmospheric Research

Type of aircraft

US Army Corps of Engineers; Wikipedia

Temperature Type

32° to 18°F Clear

18°F to 15°F Mixed

Less than 15°F Rime

Type of Icing

AFWA TN 98-002

TAFSNWS TAF:CCCC TAF 011818 18020G28KT P6SM SCT030 BKN120 TEMPO 1822 BKN020FM0400 16015KT P6SM BKN030 PROB30 0308 TSRA BKN030CBUSAF TAF:CCCC TAF 011616 03008KT 0800 PRFG FEW000 BKN005 BKN012 WS015/12035KT QNH3001INS FG FEW002 TEMPO 1820 14012G18KT 3200 -SN BLSN FEW002 OVC006 620065 SN FEW000BECMG 2324 15012G20KT 3200 -SN BLSN FEW002 OVC004 620046 QNH2983INS TM01/19Z TM04/11Z

NWS Instruction 10-813 / AFMAN 15-124

Reading the icing group

620065

6 The first digit – icing group2 The second digit – type of icing006 The third, fourth & fifth digits – height of icing5 The last digit – thickness of icing

AFMAN 15-124

http://adds.aviationweahter.noaa.gov/icing

http://adds.aviationweahter.noaa.gov/icing

Pirepshttp://adds.aviationweahter.noaa.gov/icing

Altitude

Schultz-Politovich PIREP study - University Corporation for Atmospheric Research (COMET)

Research

- Supercooled large droplet- Heat transfer- Anti-icing protection

http://www.niar.wichita.edu/researchlabs/

www.ucar.edu/communications

Technology improvements

More advancedRADARs are being tested byNational Center for Atmospheric Research

Where you can learn more

http://www.meted.ucar.edu/

The Comet program

http://www.aopa.org/asf/

AOPA Air Safety Foundation

Aircraft Icing

Thank you for your time!

Sources were cited on each slide

Questions???