1. 1 Icing Two kinds: Induction and Structural Induction Icing: Icing in the power plant –Carburetor Icing Air is cooled with adiabatic expansion andendothermic evaporation of the fuel. Cooled below 0 o C and Ice forms Carburetor icing is 51% of all icing accidents Can occur in SKC with OAT well above freezing Check your POH for when carburetor heat is needed Carb Heat reduces power, but is better than no power –Jet Engine: Can develop ice in taxi, takeoff, & climb Ch 13 Sec A

2. 2 Icing Two kinds: Induction and Structural Ch 13 Sec A

3. 3 Icing Two kinds: Induction and Structural Ch 13 Sec A

4. 4 Icing Structural Icing: Icing on the Airframe(The outside of the airplane)‏ –Skin temperature is 0 o C or less –Decrease lift efficiency of the wings –Clogs the pitot-static system –Bad altitude, VSI, and KIAS due to clogged Pitot –Adds weight to plane: may be several hundred pounds of ice. Ch 13 Sec A

5. 5 Icing Structural Icing –Types of ice protection Anti-icing: prevents ice from forming eg. Heated wing edges De-icing: Removes ice after it has formedeg. Inflatable wing boots –Ground Icing: Occurs on the ground Usually from FZRA for FZDZ or SN Can even happen to hangared planes on taxi Do not assume takeoff roll will knock of ice!! Remove all ice, snow and frost before takeoff If it is still accumulating don’t take off!!! Ch 13 Sec A

6. 6 Icing Structural Icing –An 1/8 inch coating of ice can reduce lift by 30% and increase drag by 40%. –A hard frost can increase stalling speed by 5 to 10% Ch 13 Sec A

7. 7 Icing Observing and Reporting Structural Icing Three types of ice: clear, rime, & mixed. –Rime Ice: Forms on surfaces by small droplets trapping air bubbles usually -15 o C Usually white or opaque milky color –Clear Ice: Forms between 0 o C and -5 o C Maybe translucent or a glaze Heavy and Hard Adheres strongly to the aircraft Disrupts airflow over the wing –Mixed Ice: forms from -5 o C to -15 o C Ch 13 Sec B

8. 8 Icing Observing and Reporting Structural Icing Ch 13 Sec B

9. 9 Icing PiReps AIZ UA /OV SHY321028 /TM 1609 /FL160 /TP AC68 /SK SKC /WX FV99SM /TA M09 /WV 33045KT /RM SMTH IKK UA /OV IKK360012 /TM 1815 /FL035 /TP C210 /SK SKC /TA M02 /TB MOD DEC UA /OV DEC /TM 1832 /FLUNKN /TP P28A /SK FEW-SCT052 /WX FV20SM /TB LGT /RM UPDRAFTS OF 100FT PER MIN SGF UA /OV SGF360015 /TM 2238 /FL350 /TP WW24 /SK SKC /WV 33879KT /TB INTMT-CONT LGT CHOP IRK UA /OV IRK090020/TM 2336/FL230/TP C425/TA M23/IC LGT-MOD RIME/RM FM ZKC IRK UA /OV IRK240040/TM 2353/FL220/TP B737/TA M19/IC LGT MX 190-220/RM FM ZKC MCI UA /OV BQS /TM 0048 /FLUNKN /TP B717 /TA M02 /IC TRACE RIME 150- 190 STL UA /OV STL326050/TM 0107/FL170/TP MD83/TA M15/IC LGT RIME 200- 170/RM BLW CLDS AT 160-FM ZKC STL UA /OV STL326055/TM 0158/FL150/TP E135/TA UNKN/IC NEG 240-150/RM FM ZKC FAM UA /OV FAM030025/TM 0252/FL210/TP A320/TA M19/IC LGT RIME/RM FM ZKC Ch 13 Sec B

10. 10 Icing PiReps FAM UA /OV FAM030025/TM 0252/FL210/TP A320/TA M19/IC LGT RIME/RM FM ZKC Ch 13 Sec B

11. 11 Microscale Icing Processes 3 Factors: Temperature, Droplet size, Liquid Water Conent Temperature: –Clear: 0 o C to -5 o C –Clear or Mixed:-5 o C to -10 o C –Mixed or Rime:-10 o C to -15 o C –Rime:-15 o C to -20 o C Ch 13 Sec C

12. 12 Microscale Icing Processes Liquid Water Content LWC –Icing is rapid with high LWC –Icing is slow with low LWC –LWC is greater with warmer(lower) cloud bases –LWC is less with colder(higher) cloud bases –LWC can vary within a single cloud –Cumulus usually have higher LWC –Non-Convectivie Cirrus is usually low LWC Ch 13 Sec C

13. 13 Microscale Icing Processes Droplet Size –Super-cooled Large Droplets: SLD –Maybe below freezing –>.04mm in diameter –Rain is about 5mm in diameter –SLD forms by Collision/coalescence Warm layer processes: snow falls into a warm layer(>0oC) melt and then fall into a cold layer. This happens on a warm front frontal zone. Ch 13 Sec C

14. 14 Microscale Icing Processes Droplet Size Ch 13 Sec C Icing Here

15. 15 Microscale Icing Processes Droplet Size Ch 13 Sec C

16. 16 Minimizing Icing Encounters Droplet Size Ch 13 Sec E

17. 17 Minimizing Icing Encounters See the lowest freezing level chart at: http://adds.aviationweather.gov/icing/frzg_nav.php Consult PiReps, Metars and forecasts Consult a Sounding or Skew-T at http://weather.uwyo.edu/upperair/sounding.html (Use Gif: to 10mb and click on station)‏ or http://twister.sbs.ohio-state.edu/main.php?pageloc=upperair Ch 13 Sec E

18. 18 Prevent Icing Crashes!!! 1. Prepare: Study Available Wx Info 2. Observe: Look at your plane and outside 3. Take Control: Feel your planes response to control inputs frequently Ch 13 Sec E

19. 19 Minimizing Icing Encounters – f Ch 13 Sec E

20. 20 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C   Feet Sounding SkewT at Buf

21. 21 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude

22. 22 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude

23. 23 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude

24. 24 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude

25. 25 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude

26. 26 Minimizing Icing Encounters – f Ch 13 Sec E Would you Want to fly this At 5000 feet? OAT =Tdp =-10C  Feet MEA = Minimum Enroute Altitude